bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pythium species associated with cavity spot on carrots in Norway
Authors: Hermansen A. , Herrero M.‐L. , Gauslaa E. , Razzaghian J. , Nærstad R. , Klemsdal S.S. 
Published: March 2007

AbstractCarrot roots with cavity spot lesions from eight different counties in Norway were sampled and Pythium species were isolated on selective medium. Pythium spp. were characterised morphologically and by species‐specific PCR. Laboratory experiments with inoculations of carrot roots were performed. A total of 130 isolates out of 230 Pythium‐like isolates tested with PCR were identified as pathogenic species of Pythium. These were P. intermedium (29%), P. sulcatum (23%), P. sylvaticum (16%), P. violae (15%) and a possible new Pythium species designated P. ‘vipa’ (18%). There were some differences between geographical regions and ages of cavities regarding the frequency of the different species isolated. When rating sunken lesions in the laboratory inoculation experiments, P.‘vipa’ was the most aggressive and P. violae the least aggressive species. P. intermedium and P.‘vipa’ caused more discolouration of the infected carrot tissue than the other species. The importance of the different Pythium spp. as agents of cavity spot in Norway is discussed.
Asymmetric Wolf–Rayet winds: implications for gamma-ray burst afterglows
Authors: Eldridge J. J. 
Published: March 2007

Abstract
Recent observations of Wolf–Rayet (WR) binaries WR151 and WR155 infer that their stellar winds are asymmetric. We show that such asymmetries can alter the stellar-wind bubble structure, bringing the wind-termination shock closer to the WR star. If the wind asymmetry is caused by rotation, the wind density and distance to the wind-termination shock are both decreased along the rotation axis by a factor of a few for the observed equator-to-pole wind density ratio of WR151. If this asymmetry lasts until core-collapse the time taken to reach the wind-termination shock by supernova ejecta or a gamma-ray burst jet is reduced. This leads to a distorted structure of the supernova ejecta and makes it more likely a constant density environment is inferred from gamma-ray burst afterglow observations.
The ‘Meissner effect’ and the Blandford—Znajek mechanism in conductive black hole magnetospheres
Authors: Komissarov S. S. , McKinney Jonathan C. 
Published: March 2007

Abstract
The expulsion of axisymmetric magnetic fields from the event horizons of rapidly rotating black holes has been seen as an astrophysically important effect that may significantly reduce or even nullify the efficiency of the Blandford–Znajek mechanism of powering the relativistic jets in active galactic nuclei and gamma-ray bursts. However, this Meissner-like effect is seen in the vacuum solutions of black hole electrodynamics, whereas the Blandford–Znajek mechanism is concerned with plasma-filled magnetospheres. In this Letter we argue that conductivity dramatically changes the properties of axisymmetric electromagnetic solutions – even for a maximally rotating Kerr black hole, the magnetic field is pulled inside the event horizon. Moreover, the conditions resulting in an outgoing Poynting flux in the Blandford–Znajek mechanism exist not on the event horizon but everywhere within the black hole ergosphere. Thus, the ‘Meissner effect’ is unlikely to be of interest in the astrophysics of black holes, at least not in the way this has been suggested so far. These conclusions are supported by the results of time-dependent numerical simulations that used three different computer codes. The test problems involve black holes with the rotation parameter ranging from a = 0.999 to a = 1. The pure electrodynamic simulations deal with the structure of conductive magnetospheres of black holes placed in a uniform-at-infinity magnetic field (Wald's problem) and the magnetohydrodynamic simulations are used to study the magnetospheres arising in the problem of disc accretion.
STRONTIUM ISOTOPE STRATIGRAPHY OF THE ASMARI FORMATION (OLIGOCENE ‐ LOWER MIOCENE), SW IRAN
Authors: Ehrenberg S. N. , Pickard N. A. H. , Laursen G. V. , Monibi S. , Mossadegh Z. K. , Svånå T. A. , Aqrawi A. A. M. , McArthur J. M. , Thirlwall M. F. 
Published: March 2007

The Asmari Formation has been studied in the subsurface at the Bibi Hakimeh, Marun and Ahwaz oilfields and in an outcrop section from the Khaviz anticline. It consists of approximately 400 m of cyclic platform limestones and dolostones with subordinate intervals of sandstone and shale. The method of Sr‐isotope stratigraphy is well suited for dating these strata because of the rapid rate of change of marine 87Sr/86Sr during Asmari deposition (roughly 32‐18 Ma) and the common presence of well‐preserved macrofossils.Profiles of age against depth in the four areas show a decrease from higher stratigraphic accumulation rates in the lower Asmari to lower rates in the middle to upper part of the formation. There is also a trend towards less open‐marine depositional conditions and increasing early dolomitization and anhydrite abundance above the lower part of the formation. These changes reflect the dynamics of platform progradation across the areas studied, from early deposition along relatively high accommodation margin to slope settings to later conditions of lower accommodation on the shelf top.Ages of sequence boundaries are estimated from the age‐depth profiles at each locality, providing a framework for stratigraphic correlation. Asmari deposition began in early Rupelian time (34‐33 Ma) in the Bibi Hakimeh area, when the studied areas to the NW were accumulating basinal marl facies. Progradation of the platform across the Marun and Ahwaz areas took place in mid‐Chattian time (27‐26 Ma) and somewhat later (26‐25 Ma) in the more basinward Khaviz area. Depositional sequences have durations of 1‐3 Ma, whereas component cycles represent average time intervals of 100‐300 Ky.Sr analyses of most dolomite, anhydrite and celestite samples plot close to or below the macrofossil age‐depth trend for each locality, indicating formation from waters preserving seawater 87Sr/86Sr approximately contemporaneous with or slightly younger than the time of sediment deposition. Local deviations from this trend are interpreted as indicating episodes of seepage‐reflux and also a contribution of Sr from non‐marine sources during formation of the Gachsaran cap rock anhydrite.
FLOW UNIT CLASSIFICATION FOR GEOLOGICAL MODELLING OF A HETEROGENEOUS CARBONATE RESERVOIR: CRETACEOUS SARVAK FORMATION, DEHLURAN FIELD, SW IRAN
Authors: Taghavi A. A. , Mørk A. , Kazemzadeh E. 
Published: March 2007

Flow unit classifications can be used in reservoir characterization and modelling of heterogeneous carbonate reservoirs where there is uncertainty and variability in the distribution of porosity and permeability. A flow unit classification requires the integration of geological and petrophysical data, together with reservoir engineering and production data. In this study, cores and thin sections from the upper part of the Cretaceous Sarvak Formation at the Dehluran field, SW Iran, were studied to identify flow units which were then used in reservoir modelling.Eight flow units were defined based on a classification of depositional environments and diagenetic processes and an evaluation of porosity and permeability. In lagoonal deposits, two flow units were distinguished in terms of dissolution effects (i.e. low or high values of vuggy porosity). In shoal/reef deposits, three flow units were distinguished in terms of cementation volumes and grain frequency. In open‐marine deposits, two flow units were identified with different degrees of dissolution; while intrashelf basinal deposits were characterized by a single flow unit with no observable reservoir potential.Each flow unit was characterized by unique values of porosity, permeability, water saturation and pore throat distribution. Grain‐supported deposits from high energy depositional environments (shoals) had the highest porosities and permeabilities. However, these rocks were frequently cemented with a consequent reduction in porosity and permeability. By contrast, low permeability mud‐supported deposits had undergone dissolution, forming highly permeable flow units. Capillary pressure curves from mercury injection were used to determine the distribution of pore throat sizes and the pore characteristics of the flow units, and were used to give an indication of the productivity of each flow unit.Flow units were modelled using a pixel‐based modelling tool. Modelled reservoir characteristics were mainly controlled by facies changes in the vertical direction, and by diagenetic variations in the horizontal direction. Input values for the geometry of the flow units were based on information from geological and diagenetic models of the reservoir, and from thickness maps of the flow units derived from well data.
PERMEABILITY ANISOTROPY DISTRIBUTIONS IN AN UPPER JURASSIC CARBONATE RESERVOIR, EASTERN SAUDI ARABIA
Authors: Sahin A. , Ali A. Z. , Saner S. , Menouar H. 
Published: March 2007

Most classical reservoir engineering concepts are based on homogeneous reservoirs despite the fact that homogeneous reservoirs are the exception rather than the rule. This is especially true of carbonate reservoirs in the Middle East which are known to be highly heterogeneous. The realistic petrophysical characterization of these kinds of reservoirs is not an easy task and must include the study of directional variations of permeability. Such variation can be incorporated into engineering calculations as the square root of the ratio of horizontal to vertical permeability, a parameter known as the anisotropy ratio.This paper addresses the distribution of anisotropy ratio values in an Upper Jurassic carbonate reservoir in the Eastern Province of Saudi Arabia. Based on whole core data from a number of vertical wells, statistical distributions of horizontal and vertical permeability measurements as well as anisotropy ratios were determined. The distributions of both permeability measurements and anisotropy ratios have similar patterns characterized by considerable positive skewness. The coefficients of variation for these distributions are relatively high, indicating their very heterogeneous nature.Comparison of plots of anisotropy ratios against depth for the wells and the corresponding core permeability values indicate that reservoir intervals with lower vertical permeability yield consistently higher ratios with considerable fluctuations. These intervals are represented by lower porosity mud‐rich and/or mud‐rich/granular facies. Granular facies, on the other hand, yielded considerably lower ratios without significant fluctuations.
Making generalizations about vectors: Is there a physiology of “the mosquito”?
Authors: KLOWDEN Marc J. 
Published: March 2007

AbstractMany of the generalizations made about mosquito behavior and physiology are based on the extensive research on the yellow fever mosquito, Aedes aegypti (L.). However, sufficient differences exist among the numerous species of mosquitoes that make many of these generalizations unwarranted. Some of the specific differences between Ae. aegypti and other mosquito species, particularly the important malaria vector Anopheles gambiae, are discussed.
Why pest management needs behavioral ecology and vice versa
Authors: ROITBERG Bernard D. 
Published: March 2007

AbstractBehavior manipulation is becoming an accepted tactic in pest management, however, there are many ways in which the approach can be improved. In this review, I explain how and why insect behavioral response to various stimuli can vary dramatically under different conditions and that it is this variable response that must be understood before behavior manipulation becomes widely accepted in pest management programs. I propose that entomologists use concepts from behavioral ecology to manipulate pest behavior in a predictable manner. The key is to study behaviors that maximize fitness in natural environments and then exploit these behaviors in agriculture. I provide examples from a range of behavior manipulation tactics, including use of attracticides, kairomone‐mediated biological control, use of marking pheromones, and push‐pull manipulation.
New record of Trisuloides rotundipennis Sugi (Lepidoptera: Noctuidae: Pantheinae) from Korea
Authors: HAN Hui Lin , LI Cheng‐De , BYUN Bong‐Kyu 
Published: March 2007

AbstractIn the present study, a noctuid species, Trisuloides rotundipennis Sugi, is reported for the first time from Korea. External characteristics and female genitalia and habitus of this species are illustrated, and information on host plant and distributional range is provided.
Seasonal phenology and stage‐specific parasitism of the apple ermine moth, Yponomeuta malinellus Zeller, in Korea
Authors: LEE Jang‐Hoon , PEMBERTON Robert W. 
Published: March 2007

AbstractThe apple ermine moth, Yponomeuta malinellus Zeller (Lepidoptera: Yponomeutidae), is a tent caterpillar that feeds on Malus spp. in Korea. Populations of the moth in native areas appeared to be regulated by the assemblage of parasitoids. Phenological associations between host stages and parasitoids, susceptible stage(s) of the host for each parasitoid, and stage‐specific parasitism were studied. The egg larval parasitoid Ageniaspis fuscicollis (Dalman) had highest parasitism of first instar larvae (24%), with 14% parasitism of other larval stages. Dolichogenidea delecta (Haliday) was recovered from all larval instars with the highest parasitism rate of second instar larvae (20.1%), followed by 19.9% parasitism of mid‐larval hosts. Herpestomus brunicornis Gravenhorst was reared from second instar larvae through to pupal collection, and had the highest parasitism rate (29.9%) at the pupal stage. The larval pupal parasitoid Zenillia dolosa (Meigen) was recovered from mid‐larval to pupal stages with the highest parasitism rate (5.5%) occurring in third to fourth instar larvae. The host stages for developing A. fuscicollis completely overlap with those of D. delecta, and with those of H. brunicornis to some degree. A statistically significant negative correlation exists between A. fuscicollis and these dominant parasitoids, indicating competitive interaction within the host.
Receptor‐mediated endocytosis of lipid and lipophorin by the larval fat body, adult ovary and testis in the wax moth Galleria mellonella
Authors: JUNG Eun‐Suk , YUN Hwa‐Kyung 
Published: March 2007

AbstractLipophorin (Lp) in the hemolymph of insects is known to selectively deliver lipids from sites of absorption or synthesis to sites of storage and utilization, such as the fat body, ovary and testis; however, no study regarding this has been reported in Galleria mellonella. In the present study, we examined the process by which Lp is taken up into the larval fat body, adult ovary and adult testis, and the transfer of lipid by Lp to these tissues in Galleria mellonella. To investigate the involvement of a receptor in Lp endocytosis, the larval fat body, adult ovary and adult testis were incubated for 1 h at room temperature with fluorescein isothiocyanate (FITC)‐Lp, FITC‐Lp plus unlabeled Lp, and FITC‐Lp plus suramin, a receptor endocytic inhibitor. The amounts of FITC‐Lp in the three tissues were significantly decreased in the presence of unlabeled Lp and suramin, indicating that endocytosis of Lp by the tissues is mediated by a receptor. To examine the transfer of lipid by Lp, the tissues were incubated for 1 h at room temperature with 1,1′‐dilinoleyl‐3,3,3′,3′‐tetramethylindocarbocyanine perchlorate (DiI)‐Lp, DiI‐Lp plus unlabeled Lp, and DiI‐Lp plus suramin. The transfer of lipid by Lp was inhibited in the presence of unlabeled Lp and suramin, which is consistent with a receptor‐mediated process. Our results show that the transfer process of lipid by Lp and uptake of Lp itself is by receptor‐mediated endocytosis.
GRAND CANONICAL MIXED-STATE WIGNER FUNCTION IN A MAGNETIC FIELD: de HAAS–van ALPHEN OSCILLATIONS
Authors: MATERDEY TOMAS B. 
Published: March 2007

Kohn proved in 1961 that interactions between electrons did not change the de Haas–van Alphen (dHvA) oscillation frequency for single electrons in the nondegenerate ground-state [Phys. Rev.123(4), 1242 (1961)]. It was proved recently that the pure-state Wigner function for an electron in a magnetic field carries this quantum and physical oscillation, and a quantum dielectric function, so the conductance can be calculated from the Wigner function [Int. J. Mod. Phys. B17(25), 4555 (2003)], [Int. j. Mod. Phys. B17(26), 4683 (2003)]. We present the first complete proof that at a finite temperature, the mixed-state Wigner function also shows dHvA oscillations with the same frequency. The Wigner function is a fundamental quantity, the fact that it carries observable physical information shows a great potential in the design of new quantum materials at the nanoscale. The definition of the mixed-state Wigner function involves a grand canonical partition function (GCPF). Although dHvA is a well-known phenomenon, we present the first complete proof of it happening in degenerate mixed-states, based on a GCPF, which requires reconciliation between the dHvA experimental condition of a fixed number of particles and the GCPF's sum over number of particles. The GCPF is applied to one of the two spin species, while both the spin and spin-magnetic moment interaction are considered. We show that the contour integration in ω(ε) leads to a non-oscillatory term that is much larger than an oscillatory term, in the dHvA experimental conditions of high fields and low temperatures. This dominance of the non-oscillatory term explains the constancy of the chemical potential, allowing it to reduce to the Fermi energy in the limit of zero temperature. The obtained mixed-state Wigner function shows a fundamental period of oscillation with respect to B-1 that reduces to the Onsager's period for dHvA oscillations. This indicates that in mixed-states, dHvA oscillations depend on electrons of one spin species, this means the population of electrons of each spin species oscillates with the magnetic field. The temperature dependence in the Wigner function will allow a combination of phase-space and thermodynamics information for mesoscopic structures, and the study of phase-space density holes such as BGK modes in the quantum domain.
COPING WITH COMPLEXITY AND TURBULENCE - AN ENTREPRENEURIAL SOLUTION
Authors: MASON ROGER B. 
Published: March 2007

This paper considers the adoption of an entrepreneurial orientation as a paradigm for companies operating in a complex and turbulent environment, viewing the environment as a complex and turbulent system in terms of chaos theory. Approaches suggested by chaos theory are compared with the entrepreneurial orientation to identify if such an orientation matches these suggested approaches. Literature on chaos theory and entrepreneurship is compared, and a short case is presented, providing an illustration of how a company operating successfully in a complex and turbulent environment has used the principles of an entrepreneurial orientation. The paper identifies considerable similarity between the management approaches suggested by chaos theory and the principles of the entrepreneurial orientation, indicating that chaos theory may provide the theoretical underpinning of the relationship between entrepreneurial orientation and turbulent environments. The case also shows how an entrepreneurial orientation has been successfully used in a complex and turbulent environment. The conclusion is that companies operating in a complex and turbulent environment could benefit from adopting an entrepreneurial orientation.
High-Frequency Radar Mapping of Surface Currents Using WERA
Authors: Shay Lynn K. , Martinez-Pedraja Jorge , Cook Thomas M. , Haus Brian K. , Weisberg Robert H. 
Published: March 2007

AbstractA dual-station high-frequency Wellen Radar (WERA), transmitting at 16.045 MHz, was deployed along the west Florida shelf in phased array mode during the summer of 2003. A 33-day, continuous time series of radial and vector surface current fields was acquired starting on 23 August ending 25 September 2003. Over a 30-min sample interval, WERA mapped coastal ocean currents over an ≈40 km × 80 km footprint with a 1.2-km horizontal resolution. A total of 1628 snapshots of the vector surface currents was acquired, with only 70 samples (4.3%) missing from the vector time series. Comparisons to subsurface measurements from two moored acoustic Doppler current profilers revealed RMS differences of 1 to 5 cm s−1 for both radial and Cartesian current components. Regression analyses indicated slopes close to unity with small biases between surface and subsurface measurements at 4-m depth in the east–west (u) and north–south (υ) components, respectively. Vector correlation coefficients were 0.9 with complex phases of −3° and 5° at EC4 (20-m isobath) and NA2 (25-m isobath) moorings, respectively.Complex surface circulation patterns were observed that included tidal and wind-driven currents over the west Florida shelf. Tidal current amplitudes were 4 to 5 cm s−1 for the diurnal and semidiurnal constituents. Vertical structure of these tidal currents indicated that the semidiurnal components were predominantly barotropic whereas diurnal tidal currents had more of a baroclinic component. Tidal currents were removed from the observed current time series and were compared to the 10-m adjusted winds at a surface mooring. Based on these time series comparisons, regression slopes were 0.02 to 0.03 in the east–west and north–south directions, respectively. During Tropical Storm Henri’s passage on 5 September 2003, cyclonically rotating surface winds forced surface velocities of more than 35 cm s−1 as Henri made landfall north of Tampa Bay, Florida. These results suggest that the WERA measured the surface velocity well under weak to tropical storm wind conditions.
Distinct roles of VEGFR-1 and VEGFR-2 in the aberrant hematopoiesis associated with elevated levels of VEGF
Authors: Huang Yuhui , Chen Xiaolan , Dikov Mikhail M. , Novitskiy Sergey V. , Mosse Claudio A. , Yang Li , Carbone David P. 
Published: March 2007

Abstract
Vascular endothelial growth factor (VEGF), a major factor in tumor-host interactions, plays a critical role in the aberrant hematopoiesis observed in cancer-bearing hosts. To dissect the roles of VEGF receptor (VEGFR)-1 and VEGFR-2 in cancer-associated hematopoiesis in vivo, we selectively stimulated VEGFR-1 and VEGFR-2 by continuous infusion of receptor-specific ligands or selective blockade with VEGF receptor-specific antibodies in mice infused with recombinant VEGF at levels observed in tumor-bearing animals. We found that the effect of VEGF on the accumulation of Gr1+CD11b+ cells is mediated by VEGFR-2, but that the 2 receptors have opposite effects on lymphocyte development. Pathophysiologic levels of VEGF strongly inhibit T-cell development via VEGFR-2, whereas VEGFR-1 signaling decreases this inhibition. VEGFR-1, and not VEGFR-2, signaling is responsible for the observed increase of splenic B cells. Both receptors are capable of inhibiting dendritic cell function. These data suggest that most of observed aberrant hematopoiesis caused by excess tumor-derived VEGF is mediated by VEGFR-2, and VEGFR-1 alone has very limited independent effects but clearly both positively and negatively modulates the effects of VEGFR-2. Our findings suggest that selective blockade of VEGFR-2 rather than of both receptors may optimally overcome the adverse hematologic consequences of elevated VEGF levels found in malignancy.