bluuebunny/crossref_metadata_2025 huggingface dataset:
Characteristics of speaking style and implications for speech recognition
Authors: Shinozaki Takahiro , Ostendorf Mari , Atlas Les
Published: September 2009

Differences in speaking style are associated with more or less spectral variability, as well as different modulation characteristics. The greater variation in some styles (e.g., spontaneous speech and infant-directed speech) poses challenges for recognition but possibly also opportunities for learning more robust models, as evidenced by prior work and motivated by child language acquisition studies. In order to investigate this possibility, this work proposes a new method for characterizing speaking style (the modulation spectrum), examines spontaneous, read, adult-directed, and infant-directed styles in this space, and conducts pilot experiments in style detection and sampling for improved speech recognizer training. Speaking style classification is improved by using the modulation spectrum in combination with standard pitch and energy variation. Speech recognition experiments on a small vocabulary conversational speech recognition task show that sampling methods for training with a small amount of data benefit from the new features.
Measurement of confined acoustic sources using near-field acoustic holography
Authors: Langrenne Christophe , Melon Manuel , Garcia Alexandre
Published: September 2009

Due to excessive reverberation or to the presence of secondary noise sources, characterization of sound sources in enclosed space is rather difficult to perform. In this paper a process layer is used to recover the pressure field that the studied source would have radiated in free space. This technique requires the knowledge of both acoustic pressure and velocity fields on a closed surface surrounding the source. The calculation makes use of boundary element method and is performed in two steps. First, the outgoing pressure field is extracted from the measured data using a separation technique. Second, the incoming field then scattered by the tested source body is subtracted from the outgoing field to recover free field conditions. The studied source is a rectangular parallelepiped with seven mid-range loudspeakers mounted on it. It stands at 40cm from the rigid ground of a semi-anechoic chamber which strongly modifies the radiated pressure field, especially on the underside. After the measured data have been processed, the loudspeaker positions are recovered with a fairly good accuracy. The acoustic inverse problem is also solved to calculate the velocity field on the source surface.
Quantification of material nonlinearity in relation to microdamage density using nonlinear reverberation spectroscopy: Experimental and theoretical study
Authors: Van Den Abeele K. , Le Bas P. Y. , Van Damme B. , Katkowski Tomasz
Published: September 2009

High amplitude vibrations induce amplitude dependence of the characteristic resonance parameters (i.e., resonance frequency and damping factor) in materials with microscopic damage features as a result of the nonlinear constitutive relation at the damage location. This paper displays and quantifies results of the nonlinear resonance technique, both in time (signal reverberation) and in frequency (sweep) domains, as a function of sample crack density. The reverberation spectroscopy technique is applied to carbon fiber reinforced plastic (CFRP) composites exposed to increasing thermal loading. Considerable gain in sensitivity and consistent interpretation of the results for nonlinear signatures in comparison with the linear characteristics are obtained. The amount of induced damage is quantified by analyzing light optical microscopy images of several cross-sections of the CFRP samples using histogram equalization and grayscale thresholding. The obtained measure of crack density is compared to the global macroscopic nonlinearity of the sample and explicitly confirms that the increase in nonlinearity is linked to an increased network of cracks. A change from 1% to 3% in crack density corresponds to a tenfold increase in the signature of nonlinearity. Numerical simulations based on a uniform distribution of a hysteretic nonlinear constitutive relation within the sample support the results.
An algorithm that improves speech intelligibility in noise for normal-hearing listeners
Authors: Kim Gibak , Lu Yang , Hu Yi , Loizou Philipos C.
Published: September 2009

Traditional noise-suppression algorithms have been shown to improve speech quality, but not speech intelligibility. Motivated by prior intelligibility studies of speech synthesized using the ideal binary mask, an algorithm is proposed that decomposes the input signal into time-frequency (T-F) units and makes binary decisions, based on a Bayesian classifier, as to whether each T-F unit is dominated by the target or the masker. Speech corrupted at low signal-to-noise ratio (SNR) levels (−5 and 0dB) using different types of maskers is synthesized by this algorithm and presented to normal-hearing listeners for identification. Results indicated substantial improvements in intelligibility (over 60% points in −5dB babble) over that attained by human listeners with unprocessed stimuli. The findings from this study suggest that algorithms that can estimate reliably the SNR in each T-F unit can improve speech intelligibility.
Robust acoustic particle manipulation: A thin-reflector design for moving particles to a surface
Authors: Glynne-Jones P. , Boltryk R. J. , Hill M. , Harris N. R. , Baclet P.
Published: September 2009

Existing ultrasonic manipulation devices capable of pushing particles to a surface (“quarter-wave” devices) have significant potential in sensor applications. A configuration for achieving this that uses the first thickness resonance of a layered structure with both a thin reflector layer and thin-fluid layer is described here. Crucially, this mode is efficient with lossy reflector materials such as polymers, produces a more uniform acoustic radiation force at the reflector, and is less sensitive to geometric variations than previously described quarter-wave devices. This design is thus expected to be suitable for mass produced, disposable devices.
Improved jet noise modeling using a new time-scale
Authors: Azarpeyvand M. , Self R. H.
Published: September 2009

To calculate the noise emanating from a turbulent flow using an acoustic analogy knowledge concerning the unsteady characteristics of the turbulence is required. Specifically, the form of the turbulent correlation tensor together with various time and length-scales are needed. However, if a Reynolds Averaged Navier–Stores calculation is used as the starting point then one can only obtain steady characteristics of the flow and it is necessary to model the unsteady behavior in some way. While there has been considerable attention given to the correct way to model the form of the correlation tensor less attention has been given to the underlying physics that dictate the proper choice of time-scale. In this paper the authors recognize that there are several time dependent processes occurring within a turbulent flow and propose a new way of obtaining the time-scale. Isothermal single-stream flow jets with Mach numbers 0.75 and 0.90 have been chosen for the present study. The Mani–Gliebe–Balsa–Khavaran method has been used for prediction of noise at different angles, and there is good agreement between the noise predictions and observations. Furthermore, the new time-scale has an inherent frequency dependency that arises naturally from the underlying physics, thus avoiding supplementary mathematical enhancements needed in previous modeling.
Two-dimensional model of low Mach number vortex sound generation in a lined duct
Authors: Tang S. K. , Lau C. K.
Published: September 2009

The sound generated by a vortex moving across a duct section lined with porous materials and the corresponding vortex dynamics are studied numerically in the present investigation. The combined effects of the effective fluid density, the flow resistance, the length, and the thickness of the porous linings on the vortex dynamics and sound generation are examined in detail. Results show that stronger sound radiation will take place when the length and the thickness of the porous linings are increased or when the effective fluid density is reduced. The flow resistance can only result in stronger sound radiation within a range whose width depends on the abovementioned system parameters. Such sound amplification cannot be achieved when the initial vortex height gets closer and closer to the duct centerline. The present results also indicate the strong correlation between vortex acceleration and the sound radiation under the actions of the porous linings.
Evaluating signal-to-noise ratios, loudness, and related measures as indicators of airborne sound insulation
Authors: Park H. K. , Bradley J. S.
Published: September 2009

Subjective ratings of the audibility, annoyance, and loudness of music and speech sounds transmitted through 20 different simulated walls were used to identify better single number ratings of airborne sound insulation. The first part of this research considered standard measures such as the sound transmission class the weighted sound reduction index (Rw) and variations of these measures [H. K. Park and J. S. Bradley, J. Acoust. Soc. Am. 126, 208–219 (2009)]. This paper considers a number of other measures including signal-to-noise ratios related to the intelligibility of speech and measures related to the loudness of sounds. An exploration of the importance of the included frequencies showed that the optimum ranges of included frequencies were different for speech and music sounds. Measures related to speech intelligibility were useful indicators of responses to speech sounds but were not as successful for music sounds. A-weighted level differences, signal-to-noise ratios and an A-weighted sound transmission loss measure were good predictors of responses when the included frequencies were optimized for each type of sound. The addition of new spectrum adaptation terms to Rw values were found to be the most practical approach for achieving more accurate predictions of subjective ratings of transmitted speech and music sounds.
Comparison of vu-meter-based and rms-based calibration of speech levels
Authors: Killion Mead C.
Published: September 2009

A difference of approximately 5dB exists between the level of spoken English determined using the ANSI standard vu-meter method compared to the common root-mean-square (rms) method. If the rms method is substituted for the present ANSI standard method for calibrating a speech audiometer, for example, the reported speech reception thresholds will improve 5dB: Speech levels read approximately 5dB less using rms. Similarly, the reported signal-to-noise ratio required to understand speech in a speech-spectrum noise will be 5dB better using rms. A simple method for obtaining a close approximation to traditional calibrations using a modified rms method is given.
Phonetically optimized speaker modeling for robust speaker recognition
Authors: Lee Bong-Jin , Choi Jeung-Yoon , Kang Hong-Goo
Published: September 2009

This paper proposes an efficient method to improve speaker recognition performance by dynamically controlling the ratio of phoneme class information. It utilizes the fact that each phoneme contains different amounts of speaker discriminative information that can be measured by mutual information. After classifying phonemes into five classes, the optimal ratio of each class in both training and testing processes is adjusted using a non-linear optimization technique, i.e., the Nelder–Mead method. Speaker identification results verify that the proposed method achieves 18% improvement in terms of error rate compared to a baseline system.
RNAi in Budding Yeast
Authors: Drinnenberg Ines A. , Weinberg David E. , Xie Kathleen T. , Mower Jeffrey P. , Wolfe Kenneth H. , Fink Gerald R. , Bartel David P.
Published: September 2009

Yeast Joins RNAi Club

RNA interference (RNAi) silences gene expression via small interfering (si) RNAs that bind to target sequences. RNAi has been found in almost all eukaryotes examined, with the notable exception of the budding yeast,
Saccharomyces cerevisiae
, one of the most prominent organisms used in the study of molecular biology. Indeed, RNAi has been thought to be missing from all budding yeast.

Drinnenberg
et al.

(p.
544
, published online 10 September; see the Perspective by

Moazed

) now show that several species of budding yeast do possess RNAi, which seems to act primarily on transposable elements and subtelomeric repeats. A noncanonical Dicer protein generates siRNAs that are loaded onto Ago1 protein in
S. castellii
. Introduction of these two genes into
S. cerevisiae
was sufficient to reconstitute RNAi, where it also acted to dampen the activity of transposons.
Regio- and stereoselectivity of [2+3]cycloaddition of nitroethene to (Z)-N-aryl-C-phenylnitrones
Authors: Jasiński Radomir
Published: September 2009

The cycloaddition reactions of nitroethene to (Z)-N-aryl-C-phenylnitrones lead to mixtures of stereoisomeric cis- and trans-2-aryl-4-nitro-3-phenylisoxazolidines. Regioselectivity of these reactions is determined by the character of nucleophile–electrophile interactions, while stereoselectivity is determined by the steric factors and the character of secondary orbital interactions.
Synthesis of Mn3O4 nanoparticles and their application to cancer cells
Authors: Gotić Marijan , Ivanković Siniša , Musić Svetozar , Prebeg Tatjana
Published: September 2009

The Mn3O4 nanoparticles were synthesized by optimizing the precipitation system MnCl2/H2O2/NH4OH. The material thus obtained was microstructurally characterized using X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM). The Mn3O4 nanoparticles were applied to fibroblast and cancer cells. In the concentration range 25–100 μg/ml the particles showed low cytotoxic effects on L929 fibroblast cells, medium cytotoxic effects on FsaR fibrosarcoma cells and high cytotoxic effects on SCCVII carcinoma cells. N-Acetyl-L-cysteine (NAC) increased cytotoxicity of Mn3O4 nanoparticles, which suggested that reactive oxygen species (ROS) were not responsible for their selective cytotoxic effect. It was shown that the Mn3O4 nanoparticles entered the cancer cells and aggregated inside the membrane-bound spaces that were recognized as destroyed mitochondria.
Geoelectric structure of the northeastern Williston basin and underlying Precambrian lithosphereEarth Science Sector (ESS) Contribution 20080509.
Authors: Gowan Evan J. , Ferguson Ian J. , Jones Alan G. , Craven James A.
Published: September 2009

Magnetotelluric (MT) measurements were made in southern Manitoba, Canada, as part of the Portable Observatories for Lithosphere Analysis and Research Investigating Seismicity (POLARIS) project, to image the northeastern part of the Williston basin and underlying Precambrian lithosphere. Data collected at 21 sites along a 400 km east–west profile at 49.5°N and a 300 km north–south profile at 100°W were analyzed using robust spectral analysis, tensor decomposition, and two-dimensional inversion. The resulting resistivity models allow subdivision of the Williston basin into three layers: an upper layer of 1–5 Ω·m corresponding to Mesozoic and upper Paleozoic rocks, a 20–50 Ω·m layer corresponding to lower Paleozoic carbonate rocks, and a 2–3 Ω·m layer corresponding to the Ordovician Winnipeg Formation. Deeper penetrating MT responses, interpreted with other MT data, reveal a region in the westernmost Superior craton with a southwest–northeast geoelectric fabric that is oblique to subprovince boundaries. The observations can be explained by Proterozoic deformation extending several hundred kilometres east of the Superior boundary zone or by a separate Archean terrane adjacent to the boundary. The Thompson belt (TOBE) conductor in the south of the study area has previously been interpreted as part of the Superior boundary zone (SBZ). However, MT results show that the conductor does not extend continuously along the margin of the zone and MT studies to the north define conductors on the margin of the Sask craton. The results suggest the TOBE conductor is associated with the Sask craton margin. The MT results indicate significant along-strike variation of the SBZ in southern Manitoba.
Comparative anatomy of selected basal ceratopsian dentitions
Authors: Tanoue Kyo , You Hai-Lu , Dodson Peter
Published: September 2009

The dental structure of basal ceratopsians is described. Evolutionary trends in maxillary and dentary teeth of basal ceratopsians include decrease and possible loss of enamel on the occluding side of tooth crowns, increase in the angle of wear facet, development of a prominent primary ridge and deep indentations on mesial and distal sides of the primary ridge, and increase in tooth size in neoceratopsians. Premaxillary teeth in the basalmost ceratopsian Yinlong and basal neoceratopsian Archaeoceratops oshimai exhibit wear facets and denticles along the carina, which imply use for feeding. Maxillary and dentary teeth of basal ceratopsians were probably not as effective in feeding as those in ceratopsids because of the relatively less prominent primary ridges. Some dental characters can be used to identify taxon and tooth position of isolated basal ceratopsian teeth.
High-resolution isotope stratigraphy of the Lower Ordovician St. George Group of western Newfoundland, Canada: implications for global correlation
Authors: Azmy Karem , Lavoie Denis
Published: September 2009

The Lower Ordovician St. George Group of western Newfoundland consists mainly of shallow-marine-platform carbonates (∼500 m thick). It is formed, from bottom to top, of the Watts Bight, Boat Harbour, Catoche, and Aguathuna formations. The top boundary of the group is marked by the regional St. George Unconformity. Outcrops and a few cores from western Newfoundland were sampled at high resolution and the extracted micritic materials were investigated for their petrographic and geochemical criteria to evaluate their degree of preservation. The δ13C and δ18O values of well-preserved micrite microsamples range from –4.2‰ to 0‰ (VPDB) and from –11.3‰ to –2.9‰ (VPDB), respectively. The δ13Ccarb profile of the St. George Group carbonates reveals several negative shifts, which vary between ∼2‰ and 3‰ and are generally associated with unconformities–disconformities or thin shale interbeds, thus reflecting the effect of or link with significant sea-level changes. The St. George Unconformity is associated with a negative δ13Ccarb shift (∼2‰) on the profile and correlated with major lowstand (around the end of Arenig) on the local sea-level reconstruction and also on those from the Baltic region and central Australia, thus suggesting that the St. George Group Unconformity might have likely had an eustatic component that contributed to the development–enhancement of the paleomargin. Other similar δ13Ccarb shifts have been recorded on the St. George profile, but it is hard to evaluate their global extension due to the low resolution of the documented global Lower Ordovician (Tremadoc – middle Arenig) δ13Ccarb profile.
Influence of oceanographic variability on recruitment of yellowfin tuna (Thunnus albacares) in the western and central Pacific Ocean
Authors: Langley Adam , Briand Karine , Kirby David Seán , Murtugudde Raghu
Published: September 2009

Recruitment estimates for yellowfin tuna ( Thunnus albacares ) in the western and central Pacific Ocean (WCPO), derived from a stock assessment model, are highly variable seasonally, interannually, and over decadal periods. A generalized linear model (GLM) was developed that predicts the variation in yellowfin tuna recruitment in response to a range of oceanographic variables. The GLM model accounted for 54% of the variation in quarterly recruitment for the period 1980–2003, with the inclusion of seven different oceanographic variables derived from a zone within the northwestern equatorial region of the WCPO. The robustness of the recruitment model was investigated by cross-validation. The GLM was complemented by a cluster analysis approach that identified five principal oceanographic states within the northwestern zone selected by the GLM. Incorporation of the recent GLM recruitment indices in the yellowfin tuna stock assessment model is likely to improve the precision of estimates of current and projected (next 1–2 years) biomass and exploitation rates. In a broader context, the recruitment model provides a tool to investigate how yellowfin tuna recruitment might vary in response to short- and long-term variation in the oceanographic conditions of the WCPO.
Mercury biomagnification in the food webs of acidic lakes in Kejimkujik National Park and National Historic Site, Nova Scotia
Authors: Wyn Brianna , Kidd Karen A. , Burgess Neil M. , Curry R. Allen
Published: September 2009

Mercury (Hg) concentrations in fish from acidic lakes (pH < 6.0) are typically elevated above those from near-neutral systems. It is unknown whether high biomagnification rates through the supporting food web can explain elevated Hg concentrations in top predators from low pH lakes. To investigate this, we collected yellow perch ( Perca flavescens ), brown bullhead ( Ameiurus nebulosus ), banded killifish ( Fundulus diaphanous ), golden shiner ( Notemigonus crysoleucas ), and littoral and pelagic invertebrates from four acidic lakes in Kejimkujik National Park and Historic Site (KNPNHS), Nova Scotia, Canada, and analyzed them for total Hg and methyl Hg (MeHg), and δ13C and δ15N to determine sources of energy and trophic position, respectively. Mercury biomagnification rates (slopes of log Hg versus δ15N) varied significantly among the four lakes but did not explain the among-lake differences in perch Hg; these slopes were also within the range published for near-neutral systems. Rather, Hg concentrations in yellow perch (i.e., predatory fish) in KNPNHS were higher in lakes with higher MeHg in lower-trophic-level organisms and suggest that processes influencing Hg uptake at the base of the food web are more important than rates of food web biomagnification for understanding the variation in concentrations of this contaminant among top predators.
Egg consumption in mature Pacific salmon (Oncorhynchus spp.)
Authors: Garner Shawn R. , Heath John W. , Neff Bryan D.
Published: September 2009

For over a century, conventional wisdom has maintained that Pacific salmon ( Oncorhynchus spp.) cease feeding when they return to freshwater rivers to spawn. Here, we overturn this belief by showing that multiple species of Pacific salmon consume eggs during spawning. Overall, 13% of stomachs contained eggs, and feeding rates were estimated at up to 14 eggs or 52 kJ per day. Feeding experiments revealed that mature salmon could digest eggs, as fed salmon maintained significantly higher body mass than unfed salmon. Such egg consumption presents a fundamental shift in our understanding of Pacific salmon ecology that may have important implications for migration and management models. Indeed, the energy from consumed eggs could allow salmon to migrate up to an additional 3.8 km upstream per day of feeding, or extend the duration of spawning activity by up to 12%. Furthermore, salmon stocks may have evolved local adaptations to their specific migration and spawning requirements that include nutrients from salmon eggs. Thus, successful salmon management efforts may need to preserve not only spawning habitat and migration corridors, but also feeding opportunities.
Population genetic structure in the redefined vermilion rockfish (Sebastes miniatus) indicates limited larval dispersal and reveals natural management units
Authors: Hyde John R. , Vetter Russell D.
Published: September 2009

Recent studies have revealed that the vermilion rockfish Sebastes miniatus is a cryptic species pair. The splitting of this species impacts stock size estimates and draws attention to the unintended consequences of current management policies. Differences in exploitation level between the species necessitated an evaluation of population structure and connectivity among regional management segments of the fishery. Analysis of gene flow and calculations of larval dispersal values were accomplished using 782 bp of DNA sequence data from the mitochondrial cytochrome b gene of 684 vermilion rockfish sampled from 16 sites between Kyuquot Sound, Canada, and San Quintin, Mexico. Significant genetic heterogeneity was found among sample sites (ΦST= 0.0742, p < 0.001 and FST= 0.0899, p < 0.001). Isolation by distance analysis produced a significant correlation, suggesting low average larval dispersal distance. Analysis of molecular variance showed significant partitioning of genetic variance across the biogeographic boundary at Point Conception (ΦCT= 0.0923, p < 0.001 and FCT= 0.0135, p < 0.001) with additional genetic barriers found at Cape Mendocino, Punta Colnett, Santa Monica Bay, and along the coast of Washington. These genetic barriers conform to oceanographic compartments previously proposed for the California Current Ecological Province and suggest natural management units for this species.
How different is different? Defining management and conservation units for a problematic exploited species
Authors: Bernard Andrea M. , Ferguson Moira M. , Noakes David L.G. , Morrison Bruce J. , Wilson Chris C.
Published: September 2009

Discontinuous genetic structure is widely used to delineate local, regional, and phylogenetic groups within species for conservation and management purposes. We used microsatellite markers to assess the genetic distinctiveness of putative stocks and populations of lake whitefish ( Coregonus clupeaformis ) in Ontario waters. Analysis of spawning aggregations in eastern Lake Ontario showed fish from Chaumont Bay, New York, to be weakly differentiated from spawning whitefish in and near the Bay of Quinte, Ontario. No significant differences were found between lake- and bay-spawning aggregations within the Bay of Quinte. These same genetic tools were used to test the distinctiveness and evolutionary significance of Lake Simcoe lake whitefish as a designatable unit (DU) under guidelines established by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). Although there was marked differentiation among populations from across Ontario, the Lake Simcoe population was closely allied with lake whitefish populations from Lake Ontario and Lake Huron, suggesting that a distinct status is not warranted on genetic grounds. This work demonstrates how assessing hierarchical diversity under COSEWIC’s framework can provide key information of the status of exploited populations for fishery management.
A new method to identify the fluvial regimes used by spawning salmonids
Authors: Moir Hamish J. , Gibbins Christopher N. , Buffington John M. , Webb John H. , Soulsby Chris , Brewer Mark J.
Published: September 2009

Basin physiography and fluvial processes structure the availability of salmonid spawning habitat in river networks. However, methods that allow us to explicitly link hydrologic and geomorphic processes to spatial patterns of spawning at scales relevant to management are limited. Here we present a method that can be used to link the abundance of spawning salmonids to fluvial processes at the mesoscale. We show that the frequency of spawning activity at individual morphological units (riffles, pools, runs) is quantitatively related to a number of fluvial parameters. Of these, bankfull excess shear stress (τxs) was the best predictor of spawning frequency. Results suggest that τxs can be used to represent the fluvial regimes that spawning salmon are responsive to as well as to assess the likely impacts of altered flow regimes.
Perturbations in the 4ν3 level of the {\tf="PS7CD9"{\raise7pt\tilde \lower7ptA\clap}^\lower4pt{\hskip-.5pt1}\hskip-1ptA_u} state of acetylene, C2H2This article is part of a Special Issue on Spectroscopy at the University of New Brunswick in honour of Colan Linton and Ron Lees.
Authors: Merer Anthony J. , Duan Zicheng , Field Robert W. , Watson James K.G.
Published: September 2009

Perturbations in the K = 1 and 3 levels of the [Formula: see text], 4ν3 state of acetylene are explained as interactions with levels of the [Formula: see text], 31B4 (v3 = 1, v4 + v6 = 4) polyad. A satisfactory least-squares fit to the perturbed level structure has been obtained, treating the 4ν3 state as an asymmetric top perturbed by isolated K = 1 and 3 levels. Accurate deperturbed rotational constants for the interacting states are presented.
CRDS study of auto-ionizing Rydberg states of argon in a microwave discharge This article is part of a Special Issue on Spectroscopy at the University of New Brunswick in honour of Colan Linton and Ron Lees.
Authors: van der Ende B. M. , Winslade C. , Brooks R. L. , deLaat R. H. , Westwood N. P.C.
Published: September 2009

Optical transitions from two microwave discharge excited states of argon have been observed using cavity ring-down spectroscopy. These transitions originate on the high-lying levels, 3d[1/2] 1° and 3d[3/2] 2° , and terminate on the nf ′[5/2] Rydberg (n = 8 to 22) levels, which, except for n = 8, lie between the 2P3/2 and 2P1/2 ionization thresholds. In total, 24 such spectral lines have been observed. The quantum defect for the f ′ series has been measured and is compared to previously measured values. We observe a nearly threefold jump in line width in going from n = 8 to n = 9, below and above the 2P3/2 threshold, respectively. The line widths are broad and increase monotonically with n (above 9), in contrast to the narrowing of line widths usually observed. We cannot attribute this to a single source but conclude that collisional, quasielastic l-mixing of the nf ′[5/2] Rydberg states plays a significant role.
The rotational spectrum of methanol in the third excited torsional stateThis article is part of a Special Issue on Spectroscopy at the University of New Brunswick in honour of Colan Linton and Ron Lees.We dedicate this paper to Dr. R.M. Lees, one of the early pioneers of methanol spectroscopy and internal rotation theory. Indeed, inspired by his 1968 methanol paper (Lees and Baker. J. Chem. Phys. 48, 5299 (1968)), numerous methanol studies have been matured and brought to the next level of ever challenging internal rotational problems. Among them, in the last 40 years, Ron himself has made large contributions to the understanding and advancement of the complicated methanol spectrum from pure rotation to vibration-torsion-rotation interactions. His energy maps constructed from observed transitions are continuously evolving and represent one of the most comprehensive and valuable high resolution methanol databases for a variety of applications.
Authors: Pearson J. C. , Brauer C. S. , Drouin Brian J. , Xu Li-Hong
Published: September 2009

The rotational spectrum of methanol in its third excited torsional state, vt = 3, as well as the K = 0 A-state of vt = 4, has been recorded and analyzed in the 8–1654 GHz frequency range. The vt = 3 state lies well above the top of the torsional barrier and the majority of the energy origins for the various K sub-bands lie below the C-O stretching fundamental vibration. Only the a-type R-branch spectrum was observed in this frequency range, suggesting that the near torsional degeneracy required for a b-type spectrum in the microwave accidentally reduces the torsional overlap, making these transitions very weak. The A-state K = 4 of vt = 3 interaction with the C-O stretch torsional ground state K = 0+ and K = 1+ has been accounted for. The E-state K = –5 level could be fit directly with a power series in spite of its resonance with the C-O stretch torsional ground state K = –5 level. The aR-branch of the K = 0 A-state vt = 4 sub-band is also provided and the origin of this band resonance with the C-O stretch is discussed. The data have been modeled with a power series to near experimental accuracy. The measured and calculated spectrum should facilitate radio astronomical assignments of vt = 3 transitions in hot sources.
Laboratory measurements of the (2,0) B2Δ5/2-X2Δ5/2 transition of nickel hydride using intracavity laser absorption spectroscopy This article is part of a Special Issue on Spectroscopy at the University of New Brunswick in honour of Colan Linton and Ron Lees.
Authors: Shaji Sadasivan , Song Alex , Li Moyang , O’Brien James J. , O’Brien Leah C.
Published: September 2009

The (2,0) band of the B2Δ5/2-X2Δ5/2 transition has been recorded with rotational resolution using intracavity laser absorption spectroscopy. The gas phase NiH molecules were produced in an electric discharge using a nickel hollow cathode in a pure hydrogen atmosphere at 2–3 torr total pressure. Peak positions for the NiH isotopologues are presented for these transitions. Large isotopologue splittings are observed for B2Δ5/2-X2Δ5/2 (2,0) transitions. A strong perturbation is observed in the excited state at Jf′ = 6.5. NiH isotopologue ratios in stellar spectra can be used to determine the neutron to proton ratio, with a view to probing models of supernovae and star formation.
Laser spectroscopy of the A3Φi-X3Φi and B3Φ4-X3Φ4 transitions of iridium monofluoride (IrF) This article is part of a Special Issue on Spectroscopy at the University of New Brunswick in honour of Colan Linton and Ron Lees.
Authors: Adam A. G. , Granger A. D. , Downie L. E. , Tokaryk D. W. , Linton C.
Published: September 2009

Laser-induced fluorescence spectra of iridium monofluoride (IrF) have been obtained at both low and high resolution. Two transitions have been observed; based on the rotational analysis of the high-resolution spectra, they have been assigned as A3Φi-X3Φi and B3Φi-X3Φi. For the X (ground) and B states, only the lowest Ω = 4 components have been observed, while for the A state, the two lowest components, Ω = 4 and 3, were detected. A global fit to all of the high-resolution data (six bands of A-X and five of B-X) yielded a complete set of molecular constants for all three states of both 191IrF and 193IrF. The v = 3 level of the A3Φ4 state was found to be heavily perturbed and many extra lines belonging to the perturbing state were observed for each isotopologue. A deperturbation analysis showed that the perturber is an Ω = 5 state, and molecular parameters for this state were obtained.
Study of the water retention properties of a tropical soil
Authors: Miguel Miriam Gonçalves , Vilar Orencio Monje
Published: September 2009

Some peculiarities of water retention in a tropical lateritic soil of clayey nature are presented and discussed. The typical soil microstructure is shown through thin-layer plates emphasizing soil microaggregation and pore distribution and their repercussion on the soil-water retention curve and on hysteresis. It is shown that the clayey soil has a behavior that to a large extent resembles sandy soil, which is characterized by the relatively high saturated hydraulic conductivity, low air-entry value, and small suction range at which water drainage takes place. The severe weathering processes that originated this soil have produced an altered soil that seems to be homogeneous in terms of physical indices, hydraulic conductivity, and soil-water retention characteristics, up to 4.5 m in depth.
Effect of humic acid on the behaviour of solidified dredged material
Authors: Zhu Wei , Chiu C. F. , Zhang Chun-Lei , Zeng Ke-Lin
Published: September 2009

Unconfined compression and bound-water content tests were conducted to study the effect of humic acid on the mechanical behaviour of solidified dredged material. It is found that the unconfined compressive strength (qu) and the change in bound-water content (Δmbw) exhibit similar relationships with the humic-acid content and curing time. Both parameters decrease with an increase in humic-acid content until reaching a threshold humic-acid content, above which the magnitudes of both parameters reduce to relatively low and steady values. In addition, both qu and Δmbw increase nonlinearly with the curing time. A relationship between qu and Δmbw is presented; Δmbw may reflect the extent of the hydrates developed in the solidified soil which increases nonlinearly with qu.
Yield stress, volume change, and shear strength behaviour of unsaturated soils: validation of the SFG model
Authors: Zhou Annan , Sheng Daichao
Published: September 2009

The model recently presented by Sheng, Fredlund, and Gens, known as the SFG model, provides a consistent explanation of yield stress, shear strength, and volume change behaviour of unsaturated soils as functions of suction. All these functions are based on one single equation that defines the volume change with suction and stress changes. This paper provides a systematic validation of the equation and the derived shear strength criterion against experimental data. The experimental data used include those for samples prepared from slurry soils and compacted soils. It is shown that (i) the method currently used to determine yield stresses of unsaturated soils is incorrect, (ii) volume change behaviour of unsaturated soils can be well predicted by the SFG model, and (iii) shear strength behaviour of unsaturated soils can be represented very well by the criterion in the SFG model.
Application of the 3-PGS model to assess carbon accumulation in forest ecosystems at a regional level
Authors: Nolè A. , Law B. E. , Magnani F. , Matteucci G. , Ferrara A. , Ripullone F. , Borghetti M.
Published: September 2009

In this study we assessed carbon sequestration by Italian forest ecosystems at a regional level. We applied a monthly time-step process-based model (3-PGS), coupled with a modified soil respiration model, to predict both gross primary production (GPP3-PGS) and net ecosystem production (NEP3-PGS). To evaluate the general reliability of model estimates, we compared, at five different forest sites, monthly and annual GPP3-PGS, NEP3-PGS, and predicted total ecosystem respiration (TER3-PGS) with averages of monthly and annual eddy covariance (EC) measures of GPPEC, NEPEC, and TEREC. A strong correlation was found between annual GPP3-PGSand annual GPPEC(r2= 0.77, RMSE = 1.28 Mg C·ha–1·year–1), and monthly (r2= 0.85, RMSE = 35 g C·m–2·month–1), as well as between NEP3-PGSand annual NEPEC(r2= 0.76, RMSE = 0.21 Mg C·ha–1·year–1), and monthly (r2= 0.78, RMSE = 18 g C·m–2·month–1). The TER3-PGSalso showed a high correlation with annual TEREC(r2= 0.93). Furthermore, a sensitivity analysis showed that GPP3-PGSwas highly sensitive to the satellite greenness index (normalized difference of vegetation index) and to the vapor pressure deficit. With general confidence in the models, we established a 30 year average meteorological grid of 8 km × 8 km resolution across Italy and created a map representing annual NEP3-PGSacross Italian forests, based on the remotely sensed CORINE Land Cover forest classification.
Long-term snag and downed woody debris dynamics under periodic surface fire, fire suppression, and shelterwood management
Authors: Vanderwel Mark C. , Malcolm Jay R. , Smith Sandy M.
Published: September 2009

There are pronounced differences in the processes that act to determine the type and amount of standing and downed coarse woody debris present under partial harvesting versus other noncatastrophic disturbances. To evaluate long-term differences in snag and downed woody debris (DWD) dynamics, we developed a simulation model to project snag density and DWD volume by size and decay class in white pine ( Pinus strobus L.) and red pine ( Pinus resinosa Ait.) dominated stands under (i) a high-retention shelterwood system, (ii) periodic surface fire, and (iii) fire suppression. Snag densities under a high-retention shelterwood system were consistently lower than those in the fire-suppression and surface-fire scenarios, even if no large snags were felled at the time of harvest. Regular inputs from harvest residues were important in maintaining the total volume of DWD, but this material tended to be concentrated in a narrow range of decay classes at any given time. Preserving existing DWD at harvest was less influential than the level of inputs from harvest residues. Active measures for snag creation and staggering of harvest stages among adjacent stands may help minimize differences in the overall supply and temporal variation of coarse woody debris between managed and both naturally disturbed and old-growth stands.
False rings in jack pine and black spruce trees from eastern Manitoba as indicators of dry summers
Authors: Hoffer Melissa , Tardif Jacques C.
Published: September 2009

False rings (FRs) are a tree-ring anomaly that can be used to better understand tree growth and potentially reconstruct past climatic events. The main objective of this study was to explore the association between FRs and climate, especially drought occurrence. Sampling was conducted in Nopiming Provincial Park. Wood cores were extracted from jack pine ( Pinus banksiana Lamb.) in five stands and from co-occurring black spruce ( Picea mariana (Mill.) BSP) in three of these stands. After cross-dating, earlywood, latewood, and total ring width were measured on all cores. All FRs were identified, and their position within a tree ring was determined. Both species showed similar radial growth and FR patterns. Jack pine and to a lesser extent black spruce both showed abundant FRs in the juvenile period. Springs with cool and snowy conditions and summers with severe drought were associated with a higher frequency of FRs. These anomalies could be formed partly in response to timing of the start of the growing season and to conditions during that growing season that lead to interruption and subsequent resumption of normal growth. Jack pine radial growth was found to be more sensitive to precipitation, whereas that of black spruce was more sensitive to temperature.
Logging-residue extraction does not reduce the diversity of litter-layer saprotrophic fungi in three Swedish coniferous stands after 25 years
Authors: Allmér Johan , Stenlid Jan , Dahlberg Anders
Published: September 2009

Logging residues, consisting of branches and treetops, are increasingly being extracted for biofuel purposes in Fennoscandia, thereby decreasing the availability of fine woody debris (FWD). Little is known about the importance of FWD and litter to fungal diversity, although they constitute the major components of dead organic matter in both managed and natural forests. We investigated the long-term effects of removing logging residue on the saprotrophic fungi community in the litter layer by using an experiment established 25 years ago, comprising stands with and without removal of clear-cut slash. The fungal communities were identified using terminal restriction fragment length polymorphism from standardized baits of wood and needles left in the litter layer for 30 months. A total of 74 fungal taxa were recorded. No differences in species richness or frequency of abundant species were detected between the stands with and without slash removal, suggesting that the extraction of logging residues has a negligible long-term impact on abundant saprotrophic fungi. Twenty-five of the 36 abundant species colonized wood and needles indiscriminately, while 10 species occurred exclusively on wood or needles and only one species mainly on wood. The importance of litter to certain wood-inhabiting fungi may therefore be underrated. The frequent records of Trichaptum abietinum (Dicks.) Ryvarden indicate that wood-inhabiting species may, surprisingly, be found in the litter layer.
BLACK HOLES IN THE PRESENCE OF COSMOLOGICAL CONSTANT AND LARGE-N BRANE WORLD
Authors: LUO MINGXING , ZHENG SIBO
Published: September 2009

Gravitational theories including negative cosmological constant, dilaton and gauge fields are explored in higher dimensions, in which black hole solutions are shown to exist and their asymptotic behaviors are obtained. Based on these solutions, effective Randall–Sundrum brane worlds are constructed. In the framework of gauge/gravity duality, effects from cosmological constant on the spectra of standard model fields on the branes are perturbatively calculated.
THE HIGGS CORRECTIONS TO b→sγ IN THE SM
Authors: LIN LIN , FENG TAI-FU , SUN FEI
Published: September 2009

Using the effective Lagrangian method, we analyze the corrections to the branching ratio b→sγ from the Higgs sector in the standard model. The numerical result indicates that the corrections from this sector to b→sγ is about -2% as mh~ 0.5 TeV .
PREDICTION FOR Γ(H → τ+τ-)/Γ(H → μ+μ-) FROM NON-ABELIAN FLAVOR SYMMETRY
Authors: FRAMPTON PAUL H. , MATSUZAKI SHINYA
Published: September 2009

It is shown that the ratio of branching ratios in Higgs boson decay r = Γ(H → τ+τ-)/Γ(H → μ+μ-) in a simplified (T' × Z2) model is (r)T' × Z2 ≃ 0.001. This prediction is on a footing with the successful one in (s, d) mixing, [Formula: see text]. This value for r differs from that of the minimal standard model by a very large factor (over 250,000) and can provide a smoking gun for (T' × Z2) flavor symmetry.
DECIPHERING THE SEESAW NATURE OF NEUTRINO MASS FROM UNITARITY VIOLATION
Authors: MA ERNEST
Published: September 2009

If neutrino masses are obtained via the canonical seesaw mechanism, based on an underlying 2 ×2 mass matrix, unitarity violation of the neutrino mixing matrix is unavoidable, but its effect is extremely small. On the other hand, in the inverse (and linear) seesaw mechanisms, based on an underlying 3 ×3 mass matrix, it can be significant and possibly observable. This 3 ×3 matrix is examined in more detail, and a new variation (the lopsided seesaw) is proposed which has features of both mechanisms. A concrete example based on U (1)N is discussed.
INTERACTIONS BETWEEN MODERATELY CLOSE INCLUSIONS FOR THE LAPLACE EQUATION
Authors: BONNAILLIE-NOËL VIRGINIE , DAMBRINE MARC , TORDEUX SÉBASTIEN , VIAL GRÉGORY
Published: September 2009

The presence of small inclusions modifies the solution of the Laplace equation posed in a reference domain Ω0. This question has been studied extensively for a single inclusion or well-separated inclusions. In two-dimensional situations, we investigate the case where the distance between the holes tends to zero but remains large with respect to their characteristic size. We first consider two perfectly insulated inclusions. In this configuration we give a complete multiscale asymptotic expansion of the solution to the Laplace equation. We also address the situation of a single inclusion close to a singular perturbation of the boundary ∂Ω0. We also present numerical experiments implementing a multiscale superposition method based on our first order expansion.
OPTIMAL EDGE DETECTION BY TOPOLOGICAL ASYMPTOTIC ANALYSIS
Authors: MUSZKIETA MONIKA
Published: September 2009

In this paper, we consider a variational approach to the problem of edge detection without using a priori information. To begin with, we derive an asymptotic expansion of a functional inspired by the Mumford–Shah model at its global minimum. Then, we show that, according to our model, the optimal set of image edges is indicated by the set of points for which the dominant term of this expansion is minimal and the topological derivative associated with the considered functional is equal to zero. These two conditions form the basis for the introduced method to edge detection, which does not require prior setting of parameters. The analytical results presented in this paper are additionally validated by numerical experiments.