bluuebunny/crossref_metadata_2025_split huggingface dataset:
Colonization of maize silks by Fusarium graminearum, the causative organism of gibberella ear rot
Authors: Miller S. Shea , Reid Lana M. , Harris Linda J. 
Published: July 2007

One of the most economically important diseases of maize in Canada is gibberella ear rot caused by Fusarium graminearum Schwabe (teleomorph = Gibberella zeae (Schw.) Petch). Understanding how the fungus becomes established will help in developing effective strategies to reduce the incidence of this disease. This study investigates the infection process of F. graminearum on maize silks using both a wild-type F. graminearum as well as a strain transformed with a gene from jellyfish to constitutively express green fluorescent protein. Immature ears of maize were inoculated in the field with wild-type F. graminearum and harvested at specific times post infection, and the silks were stained with Chlorazol Black E for examination. In addition, uninoculated ears were excised, placed on water agar in large Petri dishes, and the silks inoculated with a suspension of macroconidia of the transformed fungus. The progress of fungal growth was then monitored using microscopy. Germination of conidia was observed 4–6 h after inoculation. A variable period of random growth often followed, after which some of the hyphae would grow in more or less straight lines down the silk towards the cob (rachis), and ultimately infect the developing kernels. Access to the cob occurred in 7–9 d in susceptible genotypes and 12–15 d in resistant genotypes. The fungus could penetrate the ovary directly through the silk attachment point or, when the silk was growing over other kernels, the fungus could traverse from the silk to colonize interkernel spaces. Entry into the cob was either through the rachis surface via exterior growth between kernels, or into the rachis via the pedicel.
Assessing host specialization among aecial and telial hosts of the white pine blister rust fungus,Cronartium ribicola
Authors: Richardson Bryce A. , Zambino Paul J. , Klopfenstein Ned B. , McDonald Geral I. , Carris Lori M. 
Published: July 2007

The white-pine blister rust fungus, Cronartium ribicola Fisch. in Rabenh., continues to spread in North America, utilizing various aecial (primary) and telial (alternate) hosts, some of which have only recently been discovered. This introduced pathogen has been characterized as having low genetic diversity in North America, yet it has demonstrated a capacity to invade diverse environments. The recent discovery of this rust fungus on the telial host Pedicularis racemosa Dougl. ex Benth., raises questions of whether this host association represents a recent acquisition by C. ribicola or a long-standing host association that was overlooked. Here we explore two questions: (i) is host specialization detectable at a local scale and (ii) is the capacity to infect Pedicularis racemosa local or widespread? Genetic analysis of C. ribicola isolates from different aecial and telial hosts provided no evidence for genetic differentiation and showed similar levels of expected heterozygosity within a geographic population. An inoculation test showed that diverse C. ribicola sources from across North America had the capacity to infect Pedicularis racemosa. These results support a hypothesis that ability to infect Pedicularis racemosa is common in C. ribicola from North America. Utilization of Pedicularis racemosa by C. ribicola may be dependent on the co-occurrence of this host, inoculum, and favorable environments.
Highly chlorinatedEscherichia colicannot be stained by propidium iodide
Authors: Phe M.-H. , Dossot M. , Guilloteau H. , Block J.-C. 
Published: July 2007

Several studies have shown that the staining by fluorochromes (DAPI, SYBR Green II, and TOTO-1) of bacteria is altered by chlorination. To evaluate the effect of chlorine (bleach solution) on propidium iodide (PI) staining, we studied Escherichia coli in suspension and biomolecules in solution (DNA, RNA, BSA, palmitic acid, and dextran) first subjected to chlorine and then neutralized by sodium thiosulphate. The suspensions and solutions were subsequently stained with PI. The fluorescence intensity of the PI-stained DNA and RNA in solution dramatically decreased with an increase in the chlorine concentration applied. These results explain the fact that for chlorine concentrations higher than 3 μmol/L Cl2, the E. coli cells were too damaged to be properly stained by PI. In the case of highly chlorinated bacteria, it was impossible to distinguish healthy cells (with a PI-impermeable membrane and undamaged nucleic acids), which were nonfluorescent after PI staining, from cells severely injured by chlorine (with a PI-permeable membrane and damaged nucleic acids) that were also nonfluorescent, as PI penetrated but did not stain chlorinated nucleic acids. Our results suggest that it would be prudent to be cautious in interpreting the results of PI staining, as PI false-negative cells (cells with compromised membranes but not stained by PI because of nucleic acid damage caused by chlorine) are obtained as a result of nucleic acid damage, leading to an underestimation of truly dead bacteria.
Comparison of culturable fecal coliforms and Escherichia coli enumeration in freshwaters
Authors: Garcia-Armisen Tamara , Prats Josué , Servais Pierre 
Published: July 2007

Fecal coliforms (FC) counts were compared with Escherichia coli counts in differently contaminated freshwater samples (n = 166). FC were enumerated by plate count on triphenyl 2,3,5-tetrazolium chloride Tergitol medium. Escherichia coli were enumerated by the most probable number microplate method based on the detection of glucuronidase activity. FC and E. coli counts were highly correlated; an average E. coli/FC ratio equal to 0.77 was found, meaning that on average, 77% of FC were E. coli. Knowing the E. coli/FC ratio allows us to convert the historical microbiological quality data expressed in FC counts into E. coli abundance and thus to compare with present and future monitoring data that are (or will be) based on E. coli enumeration.
A new dendroecological method to differentiate growth responses to fine-scale disturbance from regional-scale environmental variation
Authors: Thompson R. Douglas , Daniels Lori D. , Lewis Kathy J. 
Published: July 2007

A new dendroecological method is developed to differentiate growth responses to fine-scale disturbance from regional-scale environmental variation. In spruce–fir forests of central British Columbia, release from suppression in response to overhead canopy tree mortality was calibrated as >60% change in radial growth (%CRG, adjacent 15 year periods compared) using gap-maker–gap-filler pairs with known years of mortality and response. Many release events, attributed to regional-scale environmental variation (e.g., bark beetle outbreaks), were counted. Species-specific regional-scale chronologies were subtracted from standardized gap-filler series producing residuals and 1 was added to all residual indices. Percent divergence (%DIV) values were calculated as the percent change in residuals (adjacent 15 year periods compared). A %DIV criterion was set at >15% increase in the residual series. The %CRG and %DIV criteria were applied to an independent data set of ring-width series, determining the date(s) of release for each tree. %CRG and %DIV criteria were used in a complementary approach to differentiate (i) release due to fine-scale canopy gaps, (ii) no response to a gap and regional-scale environmental variation, (iii) release due to regional-scale environmental variation, and (iv) response to a fine-scale canopy gap but not detected by the %CRG criterion.
Estimating coarse root biomass of balsam fir
Authors: Lavigne M.B. , Krasowski M.J. 
Published: July 2007

Root systems of 31 balsam fir ( Abies balsamea (L.) Mill.) trees were excavated at five sites in central New Brunswick. Sites ranged from 10 to >80 years in stand age; most had been thinned at least once, and densities ranged from 750 to 44 000 trees·ha–1. The relationship between diameter at breast height and coarse root biomass in the present investigation was similar to one reported for balsam fir in northern New Brunswick but differed from two other published biomass equations. Coarse root biomass per hectare ranged from 3 to 30 Mg·ha–1 among studied sites. Coarse root biomass in the smaller root diameter classes was similar at all sites, but biomass in diameter classes >50 mm increased with stand age. Precommercial thinning added 3 Mg coarse root biomass·ha–1 to the detrital pool. The ratio of coarse root biomass to stem biomass averaged 0.36 (±0.02 SE). These results show that there is more belowground biomass in balsam fir ecosystems than would be expected from the generic ratio of belowground to aboveground biomass often applied to coniferous ecosystems, pointing to a need for using ratios that are more specific.
Predicting postfire Douglas-fir beetle attacks and tree mortality in the northern Rocky Mountains
Authors: Hood Sharon , Bentz Barbara 
Published: July 2007

Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco) were monitored for 4 years following three wildfires. Logistic regression analyses were used to develop models predicting the probability of attack by Douglas-fir beetle ( Dendroctonus pseudotsugae Hopkins, 1905) and the probability of Douglas-fir mortality within 4 years following fire. Percent crown volume scorched (crown scorch), cambium injury, diameter at breast height (DBH), and stand density index for Douglas-fir were most important for predicting Douglas-fir beetle attacks. A nonlinear relationship between crown scorch and cambium injury was observed, suggesting that beetles did not preferentially attack trees with both maximum crown scorch and cambium injury, but rather at some intermediate level. Beetles were attracted to trees with high levels of crown scorch, but not cambium injury, 1 and 2 years following fire. Crown scorch, cambium injury, DBH, and presence/absence of beetle attack were the most important variables for predicting postfire Douglas-fir mortality. As DBH increased, the predicted probability of mortality decreased for unattacked trees but increased for attacked trees. Field sampling suggested that ocular estimates of bark char may not be a reliable predictor of cambium injury. Our results emphasize the important role of Douglas-fir beetle in tree mortality patterns following fire, and the models offer improved prediction of Douglas-fir mortality for use in areas with or without Douglas-fir beetle populations.
INFORMATION DISTANCE AND ITS APPLICATIONS
Authors: LI MING 
Published: July 2007

We have been developing a general theory of information distance and a paradigm of applying this theory to practical problems.[3, 19, 20] There are several problems associated with this theory. On the practical side, among other problems, the strict requirement of triangle inequality is unrealistic in some applications; on the theoretical side, the universality theorems for normalized information distances were only proved in a weak form. In this paper, we will introduce a complementary theory that resolves or avoids these problems. This article also serves as a brief expository summary for this area. We will tell the stories about how and why some of the concepts were introduced, recent theoretical developments and interesting applications. These applications include whole genome phylogeny, plagiarism detection, document comparison, music classification, language classification, fetal heart rate tracing, question answering, and a wide range of other data mining tasks.
Lp DISTANCE AND EQUIVALENCE OF PROBABILISTIC AUTOMATA
Authors: CORTES CORINNA , MOHRI MEHRYAR , RASTOGI ASHISH 
Published: July 2007

This paper presents an exhaustive analysis of the problem of computing the Lp distance of two probabilistic automata. It gives efficient exact and approximate algorithms for computing these distances for p even and proves the problem to be NP-hard for all odd values of p, thereby completing previously known hardness results. It further proves the hardness of approximating the Lp distance of two probabilistic automata for odd values of p. Similar techniques to those used for computing the Lp distance also yield efficient algorithms for computing the Hellinger distance of two unambiguous probabilistic automata both exactly and approximately. A problem closely related to the computation of a distance between probabilistic automata is that of testing their equivalence. This paper also describes an efficient algorithm for testing the equivalence of two arbitrary probabilistic automata A1 and A2 in time O(|Σ|(|A1| + |A2|)3), a significant improvement over the previously best reported algorithm for this problem.
Characterization of the Ezousas aquifer of SW Cyprus for storage–recovery purposes using treated sewage effluent
Authors: Christodoulou G.I. , Sander G.C. , Wheatley A.D. 
Published: July 2007

Ahydrogeological characterization of the Ezousas alluvial aquifer, located in SW Cyprus, has been conducted to assess its suitability for groundwater recharge with 5 Mm
3
a
−1
of chlorinated disinfected tertiary treated sewage effluent from the Paphos Municipality Wastewater Treatment Plant. We present results from a 3 year field study conducted to establish the regional groundwater regime and to define the aquifer hydrology. New drillings at selected locations were made to provide reliable information about the aquifer dimensions and boundaries. Pumping and constant-head permeability tests were used to estimate the key hydraulic properties of the aquifer system. The storage capacity was assessed to be 4.2 Mm
3
. The bedrock of the aquifer, in its approach to the sea, was found to be some 40 m below sea level, thus indicating the potential for seawater intrusion. A monitoring programme consisting of recording piezometric heads and electrical conductivities was used to observe the position of the seawater–freshwater interface, so that rates of abstraction and recharge could be determined, to maintain a stable interface. The quality of the treated sewage effluent, and of native and abstracted groundwater, was continuously assessed in terms of salinity, heavy metals, persistent organic compounds and microbiota, to optimize the quality of the downstream groundwater used for local irrigation.
Late Proterozoic rift faults and basement—cover relationships within the Ben More thrust sheet, NW Scotland
Authors: BUTLER R. W. H. 
Published: July 2007

Recently proposed models for the tectonic evolution of Northern Scotland, involving lithospheric extension during the late Precambrian, are supported by new discoveries and interpretations of early normal faults within the Moine Thrust Belt. Such structures control the preser­vation of Torridonian sediments beneath the sub-Cambrian unconform­ity. The Ben More thrust ramp from basement into the Cambrian cover may have been controlled by the early faults. Major synclines within the Ben More thrust sheet appear as tightenedhalf-grabens and thus are composite structures. This may require a re-examination of the field relationships between these folds and the apparently syn-tectonic alkaline intrusions that have been used to date thrust activity.
The Ben More thrust sheet of the Moine Thrust Belt contains the most easterly outcrops of Torridonian Supergroup (late Proterozoic) in Scotland (Fig. 1). These sediments and their Lewisian basement are unconformably overlain by the Cambrian quartzites of the Eriboll Sandstone Group. The stratigraphic relationships of these units, with the two un­conformities (Cambrian on Torridonian, Torridonian on Lewisian) discordant so that the Cambrian sediments overstep from Toridonian onto Lewisian basement, have been known for over a century. However, the nature of the overstep and its implications for the Precambrian arrangement of Torridonian and Lewisian rocks, is less established. Soper & Barber (1979) inferred the presence of major upright folds with wavelength in excess of 30 km so that Torridonian sediments lie preserved in synclines while the crests of the anticlines are eroded beneath the sub-Cambrian unconformity. This model for Precambrian basement–cover relationships has
Umbers, ocean crust and the Irish Caledonides: terrane transpression and the morphology of the Laurentian margin
Authors: WILLIAMS D. M. , HARKIN J. , RICE A. H. N. 
Published: July 2007

The Clew Bay Complex of western Ireland contains a variety of rock types. These include schists possibly of Dalradian association, amphibolites and serpentinites of unknown age, cherts, volcanic rocks and graded gabbros of mid to upper Ordovician age and shales and sandstones of Silurian age. Intercalated within the cherts of the complex on Clare Island are chocolate-brown horizons of a porous rock, geochemically comparable to hydrothermal mid-ocean ridge metalliferous sediments (e.g. umbers). These cherts overlie volcanic rocks of MORB affinities with an island arc influence. The association exposed on Clare island of graded gabbros, MORB volcanic rocks, discontinuous carbonaceous horizons, cherts, umbers and deep water shales suggest the presence of a mid- to late Ordovician spreading centre now preserved as a dismembered ophiolite.
The Clew Bay and Highland Border Complexes, both being parts of the Border Terrane, have many similarities including evidence of mid- to late Ordovician spreading, and it is suggested they formed in the same basin. However, they are dissimilar to both the South Mayo and Midland Valley Ordovician and Silurian rock associations, from which they are separated by a terrane boundary. The geochemical data and field associations do not indicate back-arc or intra-continental rifting. We suggest, therefore, that elements of older ocean crust became trapped inboard of a collided early Ordovician arc at re-entrants along the Laurentian margin. This trapped crust became the site of mid- to late Ordovician spreading. We also suggest that the site of this entrapment was to the northeast of the present positions of the Clew Bay and Highland Border Complexes and that they were emplaced into their present sites by end-Silurian transpression. This Laurentian margin morphology is compatible with that demonstrated for parts of the Newfoundland-Quebec sectors of the Appalachian sector of the orogen.
The geology of Hong Kong
Authors: FLETCHER C. J. N. 
Published: July 2007

The eight papers included in this thematic set were presented at a meeting on the geology of Hong Kong held at the University of Hong Kong on 22 January 1997. The meeting reviewed the accomplishments of the Hong Kong Geological Survey and its co-workers since it was founded fifteen years ago, and coincided with the publication of the final geological memoir of the current series that describes the 1:20 000-scale geological maps of Hong Kong. The meeting also formed part of the 20th Anniversary celebrations of the establishment of the Geotechnical Engi­neering Office of the Hong Kong Government. A total of 112 registrants from consultant companies, academic institutions, researchers from China, and several Government departments attended the meeting. In addition, 40 students from the newly established Department of Earth Sciences of Hong Kong University were present.

Hong Kong is one of the world’s major urban communities, with a population of over six million and in common with most of eastern Asia is expanding rapidly. However, development is hindered by the rugged terrain and steep-sided islands, and engineers are tackling some of the world’s largest and technically most challenging civil engineering projects. This meeting highlighted the need for systematic and accurate geological information, and the importance of understanding geological processes. It brought together geologists, geotechnical engineers and engineering geologists with the common objective to sustain the effective and safe development of Hong Kong.
The meeting was opened by the Secretary for Works, H. S. Kwong, who described the significance of the
Geochemistry of coeval Mesozoic plutonic and volcanic suites in Hong Kong
Authors: SEWELL R. J. , CAMPBELL S. D. G. 
Published: July 2007

Middle Jurassic to Lower Cretaceous intermediate to silicic plutonic and volcanic rocks of Hong Kong record a transition from calc-alkaline, through high-K calc-alkaline, to transitional shoshonitic compositions with time. Close spatial and temporal associations among comagmatic volcanic-plutonic pairs indicate that magmatism occurred in discrete episodes, mostly of less than one million years duration. Synchronous high-K calc-alkaline and transitional shoshonitic magmatic activity during at least one pulse suggests a relatively rapid transition from a subduction-related to an extension-related tectonic setting.
Geochemical signatures indicate that the magmatic suites have a mantle origin with a decreasing crustal contribution from two distinct sources. The earliest mantle-derived magmas interacted strongly with a dominantly Archaean crustal protolith. Younger magmas show evidence for interaction with a dominantly Proterozoic crustal protolith. The strongest mantle influence is shown by magmas which were intruded along the boundary between the two dominant crustal sources. This interface marks a deep crustal discontinuity which promoted the passage of magmas to the surface.
Tectonostratigraphy of the Moine Supergroup: a synthesis
Authors: SOPER N. J. , HARRIS A. L. , STRACHAN R. A. 
Published: July 2007

The Neoproterozoic (early Riphean) Moine Supergroup crops out extensively in the Scottish Caledonides north of the Great Glen and is characterized by structural complexity and monotonous siliciclastic lithology with a lack of biostratigraphic control. Despite these problems, it has become possible to combine locally defined successions into a regional stratigraphic framework. This permits an evaluation of the tectonic setting of Moine deposition, in a subsiding tract that became the Scottish part of the Laurentian margin when Iapetus opened in the Vendian.
Two major rift-basins are inferred, each of half-graben type, controlled by east-facing normal faults. The earlier Morar Group basin received a thick fill of dominantly shallow-marine arkosic sandstones, the Upper Morar Psammite forming a major regressive sequence. The Glenfinnan Group consists of mixed and muddy deposits that are interpreted partly as distal equivalents of the Morar Group, partly as a post-Morar transgressive thermal re-equilibration sequence. The Loch Eil Group, dominated by shallow marine arkosic and siliceous psammites, was deposited in a second, more easterly rift-basin that was subsequently juxtaposed with the Morar basin during Caledonian thrusting. Sediment dispersal in the major sandy sequences was northwards, and there is some evidence that provenance was, at least in part, from a mid-Proterozoic basement terrain to the south.
The extension-dominated depositional setting of the Moine Supergroup, and basin geometry, are similar to those inferred for the other major Riphean clastic sequences of Scotland, the ‘Torridonian’ of the foreland and the Grampian Group to the southeast. The latter is followed by Upper Riphean transgressive strata of the Appin Group. Scottish Riphean stratigraphy records a major pre-Iapetan cycle of lithospheric extension and thermal recovery, with no regional scale unconformities yet identified that might constitute evidence for contemporary orogenesis.