bluuebunny/crossref_metadata_2025 huggingface dataset:
Role of caveolin‐1 and cytoskeletal proteins, actin and vimentin, in adipogenesis of bovine intramuscular preadipocyte cells
Authors: Takenouchi Takato , Miyashita Norikazu , Ozutsumi Kyohei , Rose Michael T. , Aso Hisashi
Published: August 2004

We investigated the involvement of caveolin‐1 and the cytoskeletal proteins, actin and vimentin, in the adipogenesis of bovine intramuscular preadipocyte (BIP) cells. Immunoblot analysis demonstrated that levels of caveolin‐1 and actin gradually increased during adipose conversion in BIP cells, whereas a slight decrease was observed for vimentin. We found that part of the vimentin was clearly distributed to caveolin‐1‐enriched membrane fractions in BIP cells, but actin was not. During adipogenesis of BIP cells, treatment with the tubulin depolymerizer, nocodazole, significantly increased intracellular triglyceride accumulation compared to non‐treated cells. Immunocytochemical analysis showed that actin microfilaments were significantly disrupted in nocodazole‐treated cells. Also, a decrease in the localization of vimentin in caveolin‐1‐enriched fractions and a failure of vimentin to co‐immunoisolate with caveolin‐1 were observed in nocodazole‐treated cells. These results suggest that a rearrangement of cytoskeletal proteins has a role in the intracellular accumulation of lipid droplets during adipogenesis of BIP cells.
Signals through gp130 upregulate Wnt5a and contribute to cell adhesion in cardiac myocytes
Authors: Fujio Yasushi , Matsuda Takahisa , Oshima Yuichi , Maeda Makiko , Mohri Tomomi , Ito Takashi , Takatani Tomoka , Hirata Mayo , Nakaoka Yoshikazu , Kimura Ryusuke , Kishimoto Tadamitsu , Azuma Junichi
Published: August 2004

Glycoprotein 130 (gp130), a common receptor of IL‐6 family cytokines, plays critical roles in cardiac functions. Here, we demonstrate that the stimulation of gp130 with leukemia inhibitory factor (LIF) promoted cell adhesion in a cadherin‐dependent manner in cultured cardiomyocytes. Wnt5a was upregulated by the stimulation of gp130 with IL‐6 family cytokines, accompanied by N‐cadherin protein upregulation. Wnt5a was not induced by LIF in cardiomyocytes expressing dominant‐negative STAT3. Ablation of Wnt5a by antisense cDNA inhibited LIF‐induced cell adhesion. Collectively, signals through gp130 upregulate Wnt5a through STAT3, promoting the N‐cadherin‐mediated cell adhesion.
Exposure to 3,4‐methylenedioxymethamphetamine (MDMA) on postnatal days 11–20 induces reference but not working memory deficits in the Morris water maze in rats: implications of prior learning
Authors: Vorhees Charles V. , Reed Tracy M. , Skelton Matthew R. , Williams Michael T.
Published: August 2004

3,4‐Methylenedioxymethamphetamine (MDMA) in previous experiments has been shown to induce long‐term spatial and sequential learning and memory deficits in adult offspring after exposure to the drug on postnatal (P) days 11–20, but not after exposure on P1–10. Herein we further tested for the effects of MDMA (0, 5, 10 or 20 mg/kg × 2/day) after exposure on P11–20 on reference and working memory in the Morris water maze (MWM), on reference memory in the Barnes maze, and on cued learning in the visible platform version of the MWM. The MWM and Barnes mazes were counterbalanced such that half the litters received the MWM‐first and the other half received the Barnes maze first. Effects on MWM performance as a function of test order were observed. For animals that received the Barnes maze first, spatial MWM learning and memory trends were seen but they were not significantly different between MDMA groups and saline controls. For those receiving the MWM‐first, there are consistent impairments on all measures in the MDMA groups compared to controls on MWM performance (latency, path length, and cumulative distance from the goal). On probe trials, MDMA animals receiving the MWM‐first showed increased distance from the target site compared to controls. There were no MDMA effects seen on cued trials in the MWM or on straight channel swimming trials regardless of test order, indicating that MDMA had no effects on swimming ability or on the skills needed to learn the MWM. Similarly, there were no effects of MDMA on MWM working memory regardless of test order. No MDMA effects on the Barnes maze were found regardless of test order, however, the interpretation of this finding was compromised by the poor performance of the animals on this task.
Differentiating stress urinary incontinence from urge urinary incontinence
Authors: Dwyer P.L
Published: August 2004

Urinary incontinence (UI) is any involuntary leakage of urine and can be further defined according to the patient's symptoms or complaints. Stress urinary incontinence (SUI) is the complaint of involuntary leakage on effort or exertion, or on sneezing or coughing. Urge urinary incontinence (UUI) is characterized by the complaint of involuntary leakage accompanied by or immediately preceded by urgency. Mixed urinary incontinence (MUI) is the presence of both SUI and UUI symptoms. In order to effectively treat UI, an accurate diagnosis is necessary since treatment of SUI or UUI is very different. Assessment obtaining a detailed medical history includes making general assessments taking into account quality of life (QoL), performing an appropriate physical examination with cough stress test; and simple investigations namely a urinary diary, urine analysis and post‐void residual assessment and, occasionally, simple urodynamics. These assessments should suffice to commence conservative treatment. Multichannel urodynamics are required in patients presenting with more complicated UI and prior to surgery.
Duplicate Publication in the Journal of Hand Surgery
Authors: CHENNAGIRI R. J. R. , CRITCHLEY P. , GIELE H.
Published: August 2004

This study evaluates the extent of duplicate publication in the Hand Surgery literature. A retrospective review of original articles published in the American and the British & European editions of Journal of Hand Surgery during the years 1999 and 2000 was performed using MEDLINE (PUBMED) search engine. Index articles suspected of dual publication were identified by using key words in the title and the names of the first, second and last authors. The full initial text was carefully studied and suspected duplicate articles were classified as dual, potentially dual or fragmented. Six hundred articles were evaluated, of which 25 (4%) index articles were identified with 33 “suspects”. Eleven “index” and 15 “suspected” articles were cleared on closer scrutiny. Thus 14 “index” articles (2%) were found to be associated with 18 duplicated articles. Of these, four were classified as dual, five as potentially dual and nine as fragmented. We conclude that although duplicate publication of articles in the Journals of Hand Surgery (American and British/European Volumes) does occur, the incidence in the sample studied is lower than some other surgical journals.
On the inefficiency of hole boring in fast ignition
Authors: MULSER P. , SCHNEIDER R.
Published: August 2004

Hole boring and fast ignition seem to exclude each other: When there
is hole boring, no ignition occurs, and vice versa. The laser beam
pressure only causes a more or less deep cone-shaped critical surface
that leads to better guidance of the beam and to improved
laser–plasma coupling. At laser wavelengths of the order of 1
μm, successful fast ignition requires strong anomalous laser
beam–pellet coupling.
OCTN2 mutation (R254X) found in Saudi Arabian kindred: Recurrent mutation or ancient founder mutation?
Authors: Lamhonwah A.‐M. , Onizuka R. , Olpin S. E. , Muntoni F. , Tein I.
Published: August 2004

Summary: The truncating R254X mutation in the OCTN2 gene results in defective high‐affinity carnitine transport and has been previously described as a founder mutation in the Chinese population. We now report a Saudi Arabian kindred with this same mutation, suggesting that it may be a recurrent mutation or a very ancient founder mutation. Western blot analysis of skin fibroblast lysates from the proband with our specific anti‐murine Octn2 antibody revealed the absence of the OCTN2 protein.
Head imaging abnormalities in dihydropyrimidine dehydrogenase deficiency
Authors: Enns G. M. , Barkovich A. J. , van Kuilenburg A. B. P. , Manning M. , Sanger T. , Witt D. R. , van Gennip A. H.
Published: August 2004

Summary: Dihydropyrimidine dehydrogenase (DPD) deficiency is a rare autosomal recessive disorder of pyrimidine metabolism. Patients may present with a wide range of neurological symptoms during the first years of life. Head imaging abnormalities have been reported only rarely and include diffuse cerebral atrophy and white‐matter hyperintensity. The pathogenesis of the white‐matter abnormalities is unknown, although environmental factors and altered energy metabolism may be involved. To further understanding of the spectrum of brain abnormalities associated with DPD deficiency, we report a 17‐month‐old girl, born to a consanguineous Pakistani couple, who had a history of encephalopathy, prolonged hypoventilation, developmental delay and failure to thrive. Head MRI showed prominent sulci and abnormal T2 prolongation in the cerebral white matter and brainstem. Thus, DPD deficiency may feature prominent brain abnormalities involving the cerebral white matter and brainstem. Anoxic stress may have contributed to the clinical presentation and brain findings in this case. In order to define more clearly the contribution of DPD deficiency to the pathogenesis of these MRI abnormalities, we recommend performing detailed analysis of urine pyrimidine metabolites in patients who have such findings.
Early cirrhosis in a patient with type I citrullinaemia (CTLN1)
Authors: Güçer Ş. , Aşan E. , Atilla P. , Tokatl A. , Çağlar M.
Published: August 2004

Summary: A 17‐month‐old girl with type I classical citrullinaemia (CTLN1) presenting with early cirrhosis and unusual ultrastructural features of the liver is reported. The patient is homozygous for a splicing mutation in intron 15 of the argininosuccinate synthase gene.
Coping Strategies in Early and Mid-Adolescence
Authors: Plancherel Bernard , Bolognini Monique , Halfon Olivier
Published: August 2004

The way an adolescent handles different internal and external sources of stress depends partially on coping strategies. The aim of this study is to answer the following questions: Do coping strategies vary according to age and gender? And do relationships between coping and mental health vary according to age? Participants in this study consist of a community sample (N = 140; 73 girls and 67 boys, 11 through 15 years of age) in an urban area of the French-speaking part of Switzerland. The population was divided into two groups: a subsample of 70 subjects with a mean age of 12.25 years (early adolescents) and a subsample of 70 subjects with a mean age of 13.75 years (mid-adolescents). Coping was measured by the A-COPE ( Patterson & McCubbin, 1987 ).

Findings show that there are less family-oriented coping strategies and more relaxing strategies in mid-adolescents compared to early adolescents. Girls more often use social relationships as well as ventilating feelings and self-reliance, whereas boys more often use liesure. It appears that coping strategies are more useful in mid-adolescents. The buffer hypothesis is confirmed in this latter group, but not in the early-adolescent group.
Belief in Astrology as a Strategy For Self-Verification and Coping With Negative Life-Events
Authors: Lillqvist Outi , Lindeman Marjaana
Published: August 2004

This study investigated the role of astrology in self-concept verification and coping with negative life-events. Forty students in elementary courses of astrology, psychology, and German language rated their certainty about 20 self-describing attributes and three assumptions related to the self. The subjects were also asked to mark whether and how many times they had experienced particular crises and traumatic events. Participation in an astrology course, but not in psychology or German courses, verified the participant's self-concept by increasing certainty of the self-descriptive attributes and the assumptions of self-control and perceived luck. In addition, interest in astrology was positively correlated with the number of personal crises, but not with the number of past traumatic events. The motivational mechanisms underlying astrological beliefs and the enormous popularity of astrology are discussed.
Different Forms of Work Satisfaction
Authors: Büssing André , Bissels Thomas
Published: August 2004

The extended model of different forms of work satisfaction ( Büssing, 1991 ), originally proposed by Bruggemann (1974) , is suggested as a distinctive qualitative approach to work satisfaction. Six forms of work satisfaction—progressive, stabilized, resigned satisfaction, constructive, fixated, resigned dissatisfaction—are derived from the constellation of four constituent variables: comparison of the actual work situation and personal aspirations, global satisfaction, changes in level of aspiration, controllability at work. Preliminary evidence from semi-structured interviews with 46 nurses shows that the dynamic model is headed in the right direction (qualitative differentiation of consistently high propertions of satisfied employees, uncovering processes of person-work situation interaction). Qualitative methods demonstrated their usefulness in accessing underlying cognitive and evaluative processes of the forms, which are often neglected by traditional attitude-based satisfaction research.
Model parameterization and experimental design issues in nearshore bathymetry inversion
Authors: Narayanan C. , Rama Rao V. N. , Kaihatu J. M.
Published: August 2004

We present a general method for approaching inverse problems for bathymetric determination under shoaling waves. We run the Korteweg‐de Vries (KdV) model for various bathymetric representations while collecting data in the form of free‐surface imagery and time series. The sensitivity matrix provides information on the range of influence of data on the parameter space. By minimizing the parameter variances, three metrics based on the sensitivity matrix are derived that can be systematically used to make choices of experiment design and model parameterization. This analysis provides insights that are useful, irrespective of the minimization scheme chosen for inversion. We identify the characteristics of the data (time series versus snapshots, early time measurements versus long‐duration measurements, nearshore measurements versus offshore measurements), and model (bathymetry parameterizations) for inversion to be possible. We show that Bruun/Dean and Exponential bathymetric parameterizations are preferred over polynomial parameterizations. The former can be used for inversion with both time series and snapshot data, while the latter is preferably used only with snapshot data. Also, guidelines for time separation between snapshots and spatial separation between time series measurements are derived.
Jupiter's low‐frequency radio spectrum from Cassini/Radio and Plasma Wave Science (RPWS) absolute flux density measurements
Authors: Zarka P. , Cecconi B. , Kurth W. S.
Published: August 2004

We apply the calibration method developed by Dulk et al. [2001] to the data from the Cassini/Radio and Plasma Wave Science (RPWS) High‐Frequency Receiver in order to derive flux density measurements of six components of the Jovian low‐frequency radio spectrum over the full frequency range of the instrument (3.5 kHz to 16.1 MHz). The estimated accuracy is better than 50%, i.e., much less than the intrinsic variations of the flux densities of these radiosources. It is mainly limited by the accuracy of the model used for the radio galactic background. Instrumental parameters such as the antennas' effective lengths and base capacitance are constrained in the calibration process. From 6 months of calibrated data centered on the Cassini‐Jupiter flyby, we derive the average and peak Jovian radio spectrum between 3.5 and 16.1 MHz and its range of fluctuations, from which we deduce constraints on the beaming of the various radio components and estimate the power emitted by each component. Our calibration procedure also allows us to compare Cassini measurements of the Jovian radio spectrum with ground‐based measurements performed, e.g., in Nançay above the ionospheric cutoff (10−15 MHz). It will be used to derive absolute flux measurements during the Saturn tour.
Pressure, volume, density relationships in the plasma sheet
Authors: Kaufmann Richard L. , Paterson W. R. , Frank L. A.
Published: August 2004

Long‐term‐averaged three‐dimensional data‐based models of the plasma sheet were used to study relationships between the density n, pressure P, and temperature T of the plasma and between the volume V and particle content N of a tube that contains 1 Wb of magnetic flux. Near midnight a typical unit flux tube located at x0 = −11.5 RE was found to contain only 30% as many particles as a typical unit flux tube located at x0 = −29.5 RE. The average value of the adiabatic compression parameter PV5/3 was only 20% and 15% as large at x0 = −11.5 RE for ions and electrons, respectively, as at x0 = −29.5 RE. A decrease of the average N and PV5/3 can be caused by the ejection of plasmoids during reconnection. Such ejections are likely to be important beyond 20 RE. Fast flows, flux tube interchange, drift effects, and a heat flux are likely to be more important at lower altitudes. The entropy parameter Pn−5/3 was found to be relatively uniform throughout the region studied. The energy parameter TV2/3 decreased by 40% for ions and 10% for electrons near midnight between −29.5 and −11.5 RE. These energy parameter changes suggest that the most energetic ions and electrons are either being deenergized or preferentially lost, processes that may be associated with gradient and curvature drifts through the sides of the convecting flux tubes or by wave instabilities and a parallel heat flux.
Oceanic application of the active controlled flux technique for measuring air‐sea transfer velocities of heat and gases
Authors: Asher William E. , Jessup Andrew T. , Atmane Mohamed A.
Published: August 2004

Detailed understanding of the hydrodynamic mechanisms controlling the air‐sea exchange of heat and gas requires a method for rapid measurement of the associated transfer velocities. The active controlled flux technique (ACFT), where the temperature decay of a small patch of water heated by an infrared laser is tracked using an infrared imager, has been proposed as a method for making these fast noninvasive measurements of the heat and gas transfer velocities. Here, we report on ACFT measurements of the transfer velocity of heat, kH, made in the ocean during the Fluxes, Air‐sea Interactions and Remote Sensing (FAIRS) experiment (September/October, 2000) and GasEx‐01 (January/February, 2001). The results for kH from both FAIRS and GasEx‐01 compare favorably when plotted versus wind speed. However, when scaled to a Schmidt number of 660, the measured kH values were found to be a factor of two larger than gas transfer velocities measured during GasEx‐01. The ACFT‐derived kH values were combined with direct measurements of the bulk‐skin oceanic temperature difference to calculate net air‐sea heat fluxes during both experiments. Comparison of these values with heat fluxes determined by direct measurements of the latent, sensible, and radiative heat fluxes showed that the ACFT measurements are a factor of seven larger than the direct measurements. One possible theory explaining both the overprediction of the gas transfer velocities and the scale factor between the measured and calculated net heat fluxes is that air‐sea exchange is best described by surface penetration rather than surface renewal.
Scalar flux profile relationships over the open ocean
Authors: Edson J. B. , Zappa C. J. , Ware J. A. , McGillis W. R. , Hare J. E.
Published: August 2004

The most commonly used flux‐profile relationships are based on Monin‐Obukhov (MO) similarity theory. These flux‐profile relationships are required in indirect methods such as the bulk aerodynamic, profile, and inertial dissipation methods to estimate the fluxes over the ocean. These relationships are almost exclusively derived from previous field experiments conducted over land. However, the use of overland measurements to infer surface fluxes over the ocean remains questionable, particularly close to the ocean surface where wave‐induced forcing can affect the flow. This study investigates the flux profile relationships over the open ocean using measurements made during the 2000 Fluxes, Air‐Sea Interaction, and Remote Sensing (FAIRS) and 2001 GasEx experiments. These experiments provide direct measurement of the atmospheric fluxes along with profiles of water vapor and temperature. The specific humidity data are used to determine parameterizations of the dimensionless gradients using functional forms of two commonly used relationships. The best fit to the Businger‐Dyer relationship [Businger, 1988] is found using an empirical constant of aq = 13.4 ± 1.7. The best fit to a formulation that has the correct form in the limit of local free convection [e.g., Wyngaard, 1973] is found using aq = 29.8 ± 4.6. These values are in good agreement with the consensus values from previous overland experiments and the Coupled Ocean‐Atmosphere Response Experiment (COARE) 3.0 bulk algorithm [Fairall et al., 2003]; e.g., the COARE algorithm uses empirical constants of 15 and 34.2 for the Businger‐Dyer and convective forms, respectively. Although the flux measurements were made at a single elevation and local similarity scaling is applied, the good agreement implies that MO similarity is valid within the marine atmospheric surface layer above the wave boundary layer.
Hydraulic controls of summer Arctic pack ice albedo
Authors: Eicken H. , Grenfell T. C. , Perovich D. K. , Richter‐Menge J. A. , Frey K.
Published: August 2004

Linkages between albedo, surface morphology, melt pond distribution, and properties of first‐year and multiyear sea ice have been studied at two field sites in the North American Arctic between 1998 and 2001. It is shown that summer sea‐ice albedo depends critically on surface melt‐pond hydrology, controlled by melt rate, ice permeability, and topography. Remarkable short‐term and interannual variability in pond fraction varying by more than a factor of 2 and hence area‐averaged albedo (varying between 0.28 and 0.49 over the period of a few days) were observed to be forced by millimeter to centimeter changes in pond water level. Tracer studies show that the depth of the snow cover, by controlling the amount of superimposed ice formation in early summer, critically affects the retention of meltwater at the ice surface and hence affects pond coverage. Ice roughness as determined by deformation and aging processes explains a significant portion of the contrasts in pond coverage and albedo between ice of different ages, suggesting that a reduction in multiyear ice area and sea‐ice residence time in the Arctic Ocean is accompanied by large‐scale ice albedo decreases. Our work indicates that ice‐albedo prediction in large‐scale models with conventional methods is inherently difficult, if not impossible. However, a hydrological model, incorporating measured statistics of ice topography, reproduces observed pond features and variability, pointing toward an alternative approach in predicting ice albedo in numerical simulations.
Eulerian flow velocities in the swash zone: Field data and model predictions
Authors: Hughes Michael G. , Baldock Tom E.
Published: August 2004

Measurements of Eulerian flow velocity obtained within the swash zone on a relatively steep beach face (gradient 1:23) are compared with an extended ballistic swash model. The model only requires a friction factor, beach slope and terminal bore velocity as input. The following model predictions matched well with observations: (1) The maximum Eulerian flow velocity is the shoreline velocity when it arrives at the fixed point of interest on the beach face; (2) at any location the time of flow reversal occurs prior to the shoreline reaching its maximum landward excursion; (3) the maximum flow velocity in the backwash is the velocity recorded as the shoreline recedes past the fixed point of interest (and this is less than the maximum uprush velocity); and (4) the duration of the uprush flow is shorter than the duration of the backwash flow. Previous studies have already confirmed that the ballistic swash model (including friction) can accurately predict shoreline motion and maximum run‐up on steep beaches. This study shows that it is similarly successful in predicting Eulerian flow velocities during individual swash events. The model does not presently account for interacting swash, however, and so may be less appropriate on gently sloping beaches.
A modeling study of aqueous production of dicarboxylic acids: 1. Chemical pathways and speciated organic mass production
Authors: Ervens Barbara , Feingold Graham , Frost Gregory J. , Kreidenweis Sonia M.
Published: August 2004

While the formation pathways and thermodynamic properties of inorganic species (e.g., sulphate) in atmospheric aerosols are well understood, many more uncertainties exist about organics. In the present study we present oxidation pathways of organic gas phase species that lead to low volatility organic compounds (C2‐C6 dicarboxylic acids, pyruvic acid) in both the aqueous and gas phases. This mechanism is implemented in a cloud parcel model initialized with pure (NH4)2SO4 particles in 10 discrete sizes. Under clean continental conditions a few cloud processing cycles produce a total organic mass addition of ∼150 ng m−3. Individual resuspended aerosol size classes contain significant organic fractions, sometimes higher than 50%. These are likely upper bound estimates of organic mass production. In a polluted, i.e., SO2‐rich scenario, about 400 ng m−3 organic material is produced after about eight cloud cycles. Since the initial conditions in this latter case favor significant production of sulphate, the organic fraction of the aerosol mass after cloud processing represents a much lower percentage of the total aerosol mass. Oxalic, glutaric, adipic, and pyruvic acids are the main contributors to the organic fraction in both cases. In agreement with observations, the oxalate fraction in processed particles exceeds the fractions of other dicarboxylic acids since it represents an end product in the oxidation of several organic gas phase species. The study suggests that cloud processing may act as a significant source of small dicarboxylic acids, some fraction of which can be retained in the aerosol phase upon drop evaporation.
Natural and transboundary pollution influences on sulfate‐nitrate‐ammonium aerosols in the United States: Implications for policy
Authors: Park Rokjin J. , Jacob Daniel J. , Field Brendan D. , Yantosca Robert M. , Chin Mian
Published: August 2004

We use a global three‐dimensional coupled oxidant‐aerosol model (GEOS‐CHEM) to estimate natural and transboundary pollution influences on sulfate‐nitrate‐ammonium aerosol concentrations in the United States. This work is motivated in part by the Regional Haze Rule of the U.S. Environmental Protection Agency (EPA), which requires immediate action to improve visibility in U.S. wilderness areas along a linear trajectory toward an endpoint of “natural visibility conditions” by 2064. We present full‐year simulations for 1998 and 2001 and evaluate them with nationwide networks of observations in the United States and Europe (Interagency Monitoring of Protected Visual Environments (IMPROVE), Clean Air Status and Trends Network (CASTNET), National Atmospheric Deposition Program (NADP), European Monitoring and Evaluation Programme (EMEP)) and with Asian outflow observations from the NASA Transport and Chemical Evolution over the Pacific (TRACE‐P) aircraft mission. Shutting off U.S. anthropogenic emissions in the model defines “background” aerosol concentrations representing contributions from both natural and transboundary pollution sources. We find that transboundary transport of pollution from Canada, Mexico, and Asia dominates over natural influences for both sulfate and nitrate. Trans‐Pacific transport of Asian pollution accounts for 30% of background sulfate in both the western and eastern United States. Our best estimates of natural concentrations for ammonium sulfate and ammonium nitrate in the United States are either consistent with or lower than the default values recommended by EPA for natural visibility calculations. However, the large transboundary pollution influence in our calculation suggests that a natural visibility objective cannot be approached without international emission controls.
Constraints on Asian and European sources of methane from CH4‐C2H6‐CO correlations in Asian outflow
Authors: Xiao Yaping , Jacob Daniel J. , Wang James S. , Logan Jennifer A. , Palmer Paul I. , Suntharalingam Parvadha , Yantosca Robert M. , Sachse Glen W. , Blake Donald R. , Streets David G.
Published: August 2004

Aircraft observations of Asian outflow from the Transport and Chemical Evolution Over the Pacific (TRACE‐P) aircraft mission over the NW Pacific (March and April 2001) show large CH4 enhancements relative to background, as well as strong CH4‐C2H6‐CO correlations that provide signatures of regional sources. We apply a global chemical transport model simulation of the CH4‐C2H6‐CO system for the TRACE‐P period to interpret these observations in terms of CH4 sources and to explore in particular the unique constraints from the CH4‐C2H6‐CO correlations. We use as a priori a global CH4 source inventory constrained with National Oceanic and Atmospheric Administration (NOAA) Climate Monitoring and Diagnostics Laboratory (CMDL) surface observations [Wang et al., 2004]. We find that the observed CH4 concentration enhancements and CH4‐C2H6‐CO correlations in Asian outflow in TRACE‐P are determined mainly by anthropogenic emissions from China and Eurasia (defined here as Europe and eastern Russia), with only little contribution from tropical sources (wetlands and biomass burning). The a priori inventory overestimates the observed CH4 enhancements and shows regionally variable biases for the CH4/C2H6 slope. The CH4/CO slopes are simulated without significant bias. Matching both the observed CH4 enhancements and the CH4‐C2H6‐CO slopes in Asian outflow requires increasing the east Asian anthropogenic source of CH4, and decreasing the Eurasian anthropogenic source, by at least 30% for both. The need to increase the east Asian source is driven by the underestimate of the CH4/C2H6 slope in boundary layer Chinese outflow. The Streets et al. [2003] anthropogenic emission inventory for east Asia fits this constraint by increasing CH4 emissions from that region by 40% relative to the a priori, largely because of higher livestock and landfill source estimates. Eurasian sources (mostly European) then need to be reduced by 30–50% from the a priori value of 68 Tg yr−1. The decrease of European sources could result in part from recent mitigation of emissions from coal mining and landfills.
Failure of Dst index fields to represent a ring current
Authors: Campbell Wallace H.
Published: August 2004

Magnetic indices provide valuable information for space weather evaluations. The recent literature shows many scientists still believing that a Dst‐derived current circles the Earth like a ring of Saturn. Some actually use a subtraction of Dst to remove the magnetospheric contributions to surface fields. I have measured the storm time fields at paired locations to examine the ring current requirements of surface fields forming the Dst index. Also, I verified the daytime enhancement of the disturbance field at the magnetic dip equator. Two geomagnetic storms were chosen for their size, isolation, seasonal difference, and global data availability. For these storm periods, records from all available stations, within the latitude range of Dst contributors, were collected to choose those pairs of similar longitude. A daytime, dip equator, ionospheric enhancement of the storm fields was verified. Next, the 1/cos (θ) factor, used for the Dst derivation, was applied to the paired data to determine if that ring current adjustment was worthwhile. Results indicate that the local station fields behave more like those from other current sources, such as the ionosphere, and that the cosine factor, representing a magnetospheric ring current effect, typically fails. The Dst appellation “equatorial ring current index” is clearly a misnomer and should be avoided.
Stress orientations and magnitudes in the SAFOD pilot hole
Authors: Hickman Stephen , Zoback Mark
Published: August 2004

Borehole breakouts and drilling‐induced tensile fractures in the 2.2‐km‐deep SAFOD pilot hole at Parkfield, CA, indicate significant local variations in the direction of the maximum horizontal compressive stress, SHmax, but show a generalized increase in the angle between SHmax and the San Andreas Fault with depth. This angle ranges from a minimum of 25 ± 10° at 1000–1150 m to a maximum of 69 ± 14° at 2050–2200 m. The simultaneous occurrence of tensile fractures and borehole breakouts indicates a transitional strike‐slip to reverse faulting stress regime with high horizontal differential stress, although there is considerable uncertainty in our estimates of horizontal stress magnitudes. If stress observations near the bottom of the pilot hole are representative of stresses acting at greater depth, then they are consistent with regional stress field indicators and an anomalously weak San Andreas Fault in an otherwise strong crust.
Ocean tidal signals in observatory and satellite magnetic measurements
Authors: Maus S. , Kuvshinov A.
Published: August 2004

Ocean flow moves sea water through the Earth's magnetic field, inducing electric fields, currents and secondary magnetic fields. These motionally induced magnetic fields have a potential for the remote sensing of ocean flow variability. A first goal must be to gain a better understanding of magnetic field generation by tidal ocean flow. We predict the motionally induced magnetic fields for the six major tidal constituents and compare their amplitudes with the spectra of night time observatory and satellite magnetic measurements for the Indian Ocean. The magnetic variations at the solar S2, K1, and P1 periods turn out to be dominated by unrelated external fields. In contrast, observed lunar M2 and N2 tidal signals are in fair agreement with predictions from motional induction. The lunar diurnal O1 signal, visible at some observatories, could be caused by ocean flow but disagrees in amplitude with our predictions.
On the cause of eastern equatorial Pacific Ocean T‐S variations associated with El Niño
Authors: Wang Ou , Fukumori Ichiro , Lee Tong , Cheng Benny
Published: August 2004

The nature of observed variations in temperature‐salinity (T‐S) relationship between El Niño and non‐El Niño years in the pycnocline of the eastern equatorial Pacific Ocean (NINO3 region, 5°S–5°N, 150°W–90°W) is investigated using an ocean general circulation model. The origin of the subject water mass is identified using the adjoint of a simulated passive tracer. The higher salinity during El Niño is attributed to larger convergence of saltier water from the Southern Hemisphere and smaller convergence of fresher water from the Northern Hemisphere.
Investigation of polar stratospheric cloud solid particle formation mechanisms using ILAS and AVHRR observations in the Arctic
Authors: Irie H. , Pagan K. L. , Tabazadeh A. , Legg M. J. , Sugita T.
Published: August 2004

Satellite observations of denitrification and ice clouds in the Arctic lower stratosphere in February 1997 are used with Lagrangian microphysical box model calculations to evaluate nucleation mechanisms of solid polar stratospheric cloud (PSC) particles. The occurrences of ice clouds are not correlated in time and space with the locations of back trajectories of denitrified air masses, indicating that ice particle surfaces are not always a prerequisite for the formation of solid PSCs that lead to denitrification. In contrast, the model calculations incorporating a pseudo‐heterogeneous freezing process occurring at the vapor‐liquid interface can quantitatively explain most of the observed denitrification when the nucleation activation free energy for nitric acid dihydrate formation is raised by only ∼10% relative to the current published values. Once nucleated, the conversion of nitric acid dihydrate to the stable trihydrate phase brings the computed levels of denitrification closer to the measurements.
First near‐global retrievals of OH rotational temperatures from satellite‐based Meinel band emission measurements
Authors: von Savigny C. , Eichmann K.‐U. , Llewellyn E. J. , Bovensmann H. , Burrows J. P. , Bittner M. , Höppner K. , Offermann D. , Taylor M. J. , Zhao Y. , Steinbrecht W. , Winkler P.
Published: August 2004

For the first time near‐global retrievals of mesopause OH rotational temperatures from satellite‐borne Meinel band emission measurements are presented. The measurements of the OH (3‐1) Meinel band near 1.5 micron were performed with the SCIAMACHY instrument on the European Space Agency's environmental satellite Envisat. The derived OH (3‐1) rotational temperatures are shown to be in reasonable agreement with the CIRA (1986) atmosphere temperatures for the seasons and latitudes considered. The derived temperatures are in good agreement with ground‐based measurements of the OH rotational temperature performed with a CEDAR Mesospheric Temperature Mapper (MTM) at Maui, Hawaii (21°N/204°E), with the GRound based Infrared P‐branch Spectrometer I (GRIPS‐I) at Hohenpeißenberg (47°N/11°E) and with GRIPS‐II at Wuppertal (51°N/7°E). The SCIAMACHY limb nighttime observations provide a unique data set of near‐global OH rotational temperature to study seasonal and geographical variations, dynamical processes and possibly long‐term temperature trends, if an extended data set becomes available in the future.
Can the equatorial ocean quickly respond to Antarctic sea ice/salinity anomalies?
Authors: Ivchenko V. O. , Zalesny V. B. , Drinkwater M. R.
Published: August 2004

El Niño Southern Oscillation (ENSO) plays a critical role in many of the extremes or anomalies of climate, causing floods, droughts and the collapse of fisheries. Recent studies have revealed a statistically–significant link between equatorial processes and sea‐ice anomalies in the Southern Ocean. The generally accepted view is that the primary interaction of the equatorial and polar oceans takes place via the atmosphere. Indeed, the lag in these processes is usually of the order of a few months, and is much too quick to be connected with ocean currents. The question is: can climate anomaly signals effectively and rapidly propagate by another oceanic mechanism? It is demonstrated that signals generated by anomalies in the Antarctic sea‐ice cover/salinity distribution can propagate in a wave‐like manner in the form of fast‐moving barotropic Rossby waves. Such waves propagates from the Drake Passage to the western Pacific in only few days. This signal is reflected at the western boundary of the Pacific and generates an coastally trapped Kelvin wave moving equatorwards. The resulting temperature anomaly propagates northwards along the western coastline to the vicinity of the equator and increases in amplitude in time. The anomaly in the western edge of the equatorial Pacific then begins to move eastward along the equator as a trapped equatorial wave. After about 2–3 months this wave reaches the eastern coast. This process is suggested as one possible direct mechanism by which the extra–tropical ocean can induce anomalies in the equatorial ocean.
Nuclear resonant x‐ray scattering of iron hydride at high pressure
Authors: Mao Wendy L. , Sturhahn Wolfgang , Heinz Dion L. , Mao Ho‐Kwang , Shu Jinfu , Hemley Russell J.
Published: August 2004

We studied the nuclear resonant x‐ray scattering of iron hydride (FeHx) up to 52 GPa. Coupled with hydrostatic x‐ray diffraction data, the partial phonon density of states measured by nuclear resonant inelastic x‐ray scattering provides information on sound velocities and the Fe contribution to thermodynamic parameters. In particular it constrains the aggregate shear velocity and shear modulus for comparison to seismic observations. We found that VS (km/sec) = 0.023*P (GPa) + 3.2. A loss of magnetism was observed with synchrotron Mössbauer spectroscopy at 22 GPa, lower than theoretically predicted but consistent with the observed anomalous velocity behavior. Results confirm that FeHx could be a major light element bearing phase for explaining the core density deficit relative to pure Fe. Formation of FeHx by reaction with water would be expected to leave a signature in the mantle.
Absolute differential cross sections for direct scattering of keV O+ ions by He, H2, N2, and O2
Authors: Lindsay B. G.
Published: August 2004

Accurate atomic scattering cross sections are essential for modeling energetic particle precipitation into the upper atmosphere. Here, measurements of absolute differential cross sections for direct scattering of O+ ions by He, H2, N2, and O2 are reported. The measured cross sections include contributions from both elastic and inelastic scattering processes. Data are presented for 0.5‐, 1.5‐, and 5‐keV projectile energies over the laboratory angular range 0.22°–4.68°. Additionally, a simple numerical technique is used to estimate the scattering cross sections for He, N2, and O2 at 0.1 keV. At a given energy, the cross sections for different targets exhibit a high degree of similarity in both amplitude and angular dependence. This observation suggests that the cross sections for targets such as O and H, which are much more difficult to study in the laboratory and for which measurements are not available, may be approximated by an average of the data presented here.
Modeled and observed empirical orthogonal functions of currents in the Yucatan Channel, Gulf of Mexico
Authors: Oey Lie‐Yauw , Ezer Tal , Sturges Wilton
Published: August 2004

Candela et al. [2003] have reported empirical orthogonal function (EOF) analyses based on 23‐month current‐meter and acoustic Doppler current profiler measurements in the Yucatan Channel. Those authors noted the difference between EOFs obtained from observations and their z‐level models and EOFs calculated by Ezer et al. [2003] from the results of a terrain‐following model. Here a new analysis is reported that explains this difference, and that also suggests the importance of shelf‐edge meander mode of the core Loop Current in the channel. We show that the terrain‐following model gives EOFs with characteristics similar to those observed when data from the upper slope and shelf in the western portion of the model channel are omitted. Modes 1 and 2 have tripole and dipole structures with energies (35%, 26%), respectively, of total energy, and correlate with “slow” vacillation of the core‐current for periods >50 days. Exclusion of upper‐slope and shelf data eliminates a short‐period and energetic component inherent in Ezer et al.'s original mode 1 EOF. This mode correlates with frontal meanders of the core current over the shelf edge in the western portion of the channel. The short‐period mode may be missing or underestimated in observational and z‐level models' analyses, since there were only a few moorings over the upper slope and shelf, and z‐level models have step‐like topography with generally lower resolution in shallower seas.
Crustal structure of Mars from gravity and topography
Authors: Neumann G. A. , Zuber M. T. , Wieczorek M. A. , McGovern P. J. , Lemoine F. G. , Smith D. E.
Published: August 2004

Mars Orbiter Laser Altimeter (MOLA) topography and gravity models from 5 years of Mars Global Surveyor (MGS) spacecraft tracking provide a window into the structure of the Martian crust and upper mantle. We apply a finite‐amplitude terrain correction assuming uniform crustal density and additional corrections for the anomalous densities of the polar caps, the major volcanos, and the hydrostatic flattening of the core. A nonlinear inversion for Moho relief yields a crustal thickness model that obeys a plausible power law and resolves features as small as 300 km wavelength. On the basis of petrological and geophysical constraints, we invoke a mantle density contrast of 600 kg m−3; with this assumption, the Isidis and Hellas gravity anomalies constrain the global mean crustal thickness to be >45 km. The crust is characterized by a degree 1 structure that is several times larger than any higher degree harmonic component, representing the geophysical manifestation of the planet's hemispheric dichotomy. It corresponds to a distinction between modal crustal thicknesses of 32 km and 58 km in the northern and southern hemispheres, respectively. The Tharsis rise and Hellas annulus represent the strongest components in the degree 2 crustal thickness structure. A uniform highland crustal thickness suggests a single mechanism for its formation, with subsequent modification by the Hellas impact, erosion, and the volcanic construction of Tharsis. The largest surviving lowland impact, Utopia, postdated formation of the crustal dichotomy. Its crustal structure is preserved, making it unlikely that the northern crust was subsequently thinned by internal processes.
Average contaminant concentration and mass flow in aquifers from time‐dependent pumping well data: Analytical framework
Authors: Bayer‐Raich Martí , Jarsjö Jerker , Liedl Rudolf , Ptak Thomas , Teutsch Georg
Published: August 2004

Conventional water samples are representative for small subsurface volumes relative to the scale of many natural (geological) heterogeneities. We present an analytical framework for estimation of representative field‐scale average concentrations and mass flows on the basis of much larger sampling volumes that are obtained through so‐called integral pumping tests. The contaminant concentration is then measured as a function of time in a pumping well and used for estimation of the conditions in the aquifer prior to (and after) pumping, increasing the observation scale to the size of the well capture zone. This method complements (and provides an alternative to) conventional monitoring grids, where mass flow and concentration may be misinterpreted or plumes even missed because of problems related to grid spacing. The (not measured) initial spatial concentration distribution and the time‐dependent concentration measured at the well are related through a Volterra integral equation of the first kind. For limiting cases of short and long dimensionless pumping duration, two closed form analytical solutions are given, from which the mass flow and average concentration can be evaluated. Furthermore, a new solution for evaluating integral pumping tests of any duration is provided and used for investigating the applicability of the simple, analytical closed form solutions for interpreting test results from seven large‐scale contaminated sites in Europe.
β1‐Integrins induce phosphorylation of Akt on serine 473 independently of focal adhesion kinase and Src family kinases
Authors: Velling Teet , Nilsson Stina , Stefansson Anne , Johansson Staffan
Published: August 2004

Adhesion by means of β1‐integrins induces the phosphorylation of Akt, an event strictly dependent on the activity of the phosphatidylinositol 3‐kinase (PI3K). Binding of the p85 regulatory subunit of PI3K to phosphorylated tyrosine 397 in focal adhesion kinase (FAK) is considered to be the mechanism of cell adhesion‐induced activation of class Ia PI3K. Here we show that PI3K‐dependent phosphorylation of Akt in response to ligation of β1‐integrins occurs efficiently in the absence of FAK tyrosine phosphorylation. Akt S473 phosphorylation was strongly promoted both in cells expressing the integrin subunit splice variant β1B, which is unable to activate FAK, and in FAK knockout cells. In addition, we found this phosphorylation to be independent of the Src family kinases Src, Fyn and Yes. These results indicate that a major pathway for adhesion‐dependent activation of PI3K/Akt is triggered by the membrane proximal part of the β1 subunit in a FAK and Src‐independent manner.