bluuebunny/crossref_metadata_2025 huggingface dataset:
Neoarchean trans-subprovince sediment transport in southwestern Superior Province: sedimentological, geochemical, and geochronological evidence
Authors: Fralick Philip , Purdon R H , Davis D W
Published: October 2006

At ~2700 Ma volcanism spawned by northward-directed subduction under Wabigoon subprovince, Canadian Shield, fed sediment into an adjacent fore-arc basin – trench system. Volcanically active island arcs to the south (Wawa subprovince) were transported northward during this interval and at ~2690 Ma collided with the accretionary complex (Quetico subprovince). Metamorphosed sedimentary units intercalated with the ocean floor and island-arc volcanic rocks of northern Wawa subprovince provided the opportunity to amass data useful in extending the paleogeographic interpretation of the area. This study examines the McKellar Harbour Formation, a several kilometre thick assemblage of graded metasandstone beds outcropping to the north of Lake Superior. Its sedimentology, geochemistry, and detrital U–Pb zircon geochronology were investigated in conjunction with the same attributes of possible correlative units in the region. Similarities between the McKellar Harbour Formation and sedimentary rocks composing the fore-arc basin and Quetico trench to the north indicate that by 2696 Ma the trench had been overwhelmed by sediment, to the point where turbidity currents were overflowing onto the abyssal ocean plain, building a prograding submarine ramp–fan that was to become the McKellar Harbour Formation. The turbiditic ramp–fan assemblage comprising most of this extensive depositional system crosses much of southern Superior Province, highlighting the interrelated genesis of rocks formed during amalgamation of the individual subprovinces.
The Western Superior Province Lithoprobe and NATMAP transects: introduction and summary
Authors: Percival John A , Helmstaedt Herwart
Published: October 2006

The Special Issue on the Western Superior Province Lithoprobe and NATMAP transects presents a wide spectrum of contributions from coordinated, multidisciplinary research projects on the western region of Earth's largest Archean craton. Articles include aspects of the geophysical, stratigraphic, geochemical, geochronological, petrological, and structural evidence bearing on the accretionary history of this classic, well-exposed piece of ancient continental crust, as well as analyses of the prospectivity and seismic character of the gold-rich Red Lake greenstone belt.
Benthic grazing and functional compensation in stressed and recovered lakes
Authors: Hogsden Kristy L , Vinebrooke Rolf D
Published: October 2006

During ecosystem recovery, grazing pressure is expected to increase as larger herbivores become reestablished. Alternatively, grazing pressure may remain unchanged during recovery as large consumers replace and functionally compensate for more abundant populations of smaller, tolerant herbivores. We tested these hypotheses by conducting a 90-day experiment in which three size categories of benthic consumers were excluded from producers in three chemically stressed and three recovered lakes. Our findings showed that consumers did not significantly affect producer biomass in either type of lake. However, exposure to larger and more abundant grazers did induce a physiognomic shift towards less edible producers in the recovered lakes. In comparison, recovered lakes contained significantly greater producer biomass and diversity. Comparison of the observed subtle effects of consumers and pronounced negative impact of ecosystem stress on benthic producers suggest that they can compensate for natural disturbances (e.g., grazing), but not for the other multiple stressors associated with anthropogenic acidification of the Killarney lakes.
Effect of lipid extraction on the interpretation of fish community trophic relationships determined by stable carbon and nitrogen isotopes
Authors: Murry Brent A , Farrell John M , Teece Mark A , Smyntek Peter M
Published: October 2006

Stable isotopes of carbon (C) and nitrogen (N) are commonly used to evaluate trophic relationships and food web structure; however, the decision to extract lipids or not may influence the interpretation of results. Lipid extraction is not a universal practice, thus pooling or comparing results across studies may not always be appropriate. Additionally, common lipid extraction techniques remove not only lipids, but also N-containing compounds that may alter the δ15N value of a sample. We examined differences in the interpretation of fish community trophic structure derived from δ13C and δ15N stable isotope data based on lipid-extracted and nonextracted samples from nine freshwater fish species. Lipid extraction significantly increased δ13C and δ15N, causing a positive shift in overall food web placement. The magnitude of isotopic change did not, however, differ among species, such that the overall interpretation of the fish community structure was not altered. The consistent increase in both C and N isotopes did, however, significantly alter the placement of the food web in coordinate space relative to nonextracted webs. Cross-study comparisons need to consider these procedural inconsistencies when drawing conclusions from multiple studies.
Bioaccumulation of newly deposited mercury by fish and invertebrates: an enclosure study using stable mercury isotopes
Authors: Paterson Michael J , Blanchfield Paul J , Podemski Cheryl , Hintelmann Holger H , Gilmour Cynthia C , Harris Reed , Ogrinc Nives , Rudd John WM , Sandilands Ken A
Published: October 2006

Enriched stable mercury (Hg) isotopes were added to four 10 m diameter enclosures in Lake 239 at the Experimental Lakes Area to increase inorganic Hg loading. Our main objectives were to (i) follow low-level additions (spikes) of isotope-enriched Hg through the biogeochemical cycle and into the food web and (ii) determine the relative contribution of newly deposited Hg to methyl Hg (MeHg) accumulation by fish and other biota. The experiment ran for two summers (2000, 2001), with different enriched Hg isotopes being added each year. Within 1 month of beginning additions in 2000, spike Hg was detected in water, zooplankton, and benthic invertebrates as MeHg, and in fish as total Hg (THg; the sum of inorganic and organic Hg). In 2001, concentrations in water of inorganic spike Hg added in 2000 were near detection limits, but concentrations of 2000 spike MeHg in water and biota remained unchanged or greater. Despite comparatively large increases in inorganic Hg loading, accumulation of ambient, non-spike MeHg predominated in all organisms, and spike MeHg never comprised more than 15%, even after 1 year. Our results suggest that changes in Hg loading will affect MeHg concentrations in fish and other biota, but that steady state may not be achieved for at least 10–30 years under conditions similar to our enclosures.
Diel vertical migration in the Lake Superior pelagic community. II. Modeling trade-offs at an intermediate trophic level
Authors: Jensen Olaf P , Hrabik Thomas R , Martell Steven J.D. , Walters Carl J , Kitchell James F
Published: October 2006

Several hypotheses have been proposed to explain diel vertical migration (DVM); however, they have generally been applied to DVM behavior of a single trophic level. We evaluate the costs (predation risk) and benefits (foraging rate and growth rate potential) of different hypothetical and observed DVM trajectories for a three-level pelagic food chain in Lake Superior containing opossum shrimp (Mysis relicta), deepwater ciscoes (Coregonus spp.), and lake trout (Salvelinus namaycush). Lake trout appear to be maximizing foraging and growth rates by tracking vertically migrating ciscoes, while the DVM trajectories of ciscoes suggests a trade-off between predation risk and growth. For ciscoes, two alternative DVM trajectories both minimize the ratio of risk to growth: a shallow trajectory that follows low light levels down to 80 m during the day and a deep trajectory (below 150 m) that tracks highest Mysis densities. Observed cisco DVM trajectories appear to follow the shallow high risk – high growth trajectory in 2001, but switch to the deep, low risk – low growth trajectory in 2004 when lake trout density was higher and the density of ciscoes was lower.
Relation of soil-, surface-, and ground-water distributions of inorganic nitrogen with topographic position in harvested and unharvested portions of an aspen-dominated catchment in the Boreal Plain
Authors: Macrae M L , Devito K J , Creed I F , Macdonald S E
Published: October 2006

Spatial distributions of soil extractable nitrate (NO3) and ammonium (NH+4) concentrations were related to surface- and ground-water NO3and NH+4concentrations in harvested and forested sections of a catchment dominated by trembling aspen (Populus tremuloides Michx.) in the subhumid boreal forest of Alberta, Canada. NO3and NH+4concentrations in soils varied spatially throughout the catchment and were larger in surface soils than in subsurface soils. Spatial distributions of soil inorganic nitrogen (N) concentrations were not explained by the harvested versus the unharvested condition; heterogeneity was instead related to topographic position. NO3concentrations in both surface and subsurface soils were largest in ephemeral draws and wetlands. NH+4concentrations in subsurface soils were largest in ephemeral draws and wetlands, but this pattern was not apparent for surface soils. Soil NO3and NH+4availability and surface- and ground-water NO3and NH+4concentrations reflected soil NO3and H+4concentrations. N-rich surface soils in both forested and harvested areas have a large potential for releasing N to surface waters. This study indicates that even though topography is subtle in this catchment, topographic position and its soil moisture relations, along with vegetation demand, can influence N transformation and transport in both forested and harvested portions of the Boreal Plain landscape.
Post hoc blocking to improve heritability and precision of best linear unbiased genetic predictions
Authors: Gezan Salvador A , Huber Dudley A , White Timothy L
Published: October 2006

Single-site clonal trials were simulated with a total of 256 clones "planted" in single-tree plots with three different environmental patterns: only patches (PATCH), only gradients (GRAD), and both components (ALL). Several simulated experimental designs were analyzed (a randomized complete block design; incomplete block designs with 4, 8, 16, and 32 incomplete blocks; and a row-column design) and compared with post hoc blocking of the same designs over a randomized complete block. Additionally, two more incomplete block designs (64 and 128 blocks) were superimposed after the fact to examine extremely small blocks. To select the best fit, the performance of the log-likelihood and mean standard error of the difference (SED) were studied and compared with mean individual broad-sense heritability. Improvement in statistical efficiency (or precision) were obtained with little effort using post hoc blocking. The results from post hoc blocking were promising with negligible differences compared with predesigned local control. The post hoc best designs were row-column (for ALL and PATCH) and incomplete block with eight blocks (for GRAD). Also, mean correlation between the true and predicted values (CORR) showed a reduction in efficiency for extremely small blocks, but no reduction in the genetic variance was noted as the size of the block decreased. Both of the criteria for model selection (log-likelihood and SED) showed similar trend to mean CORR, and their use is recommended.
Comparison of height growth and growth intercept models of jack pine plantations and natural stands in northern Ontario
Authors: Guo Jin-ping , Wang Jian R
Published: October 2006

Accurate estimates of forest productivity are required for sustainable forest management. Sixty-five jack pine (Pinus banksiana Lamb.) plantations (<50 years of age) were sampled to develop height growth and variable growth intercept (GI) models for jack pine plantations in northern Ontario, Canada. Based on the residual plots and model-fitting statistics, these models can be recommended for estimating site index (SI) of young (<40 years) jack pine plantations. To compare SI of plantations with that of natural stands, we used stem-analysis data from 383 plots of natural jack pine stands (aged 50157 years) from the same geographic region to develop the GI models for natural stands. Also, polymorphic SI curves were developed for young (<40 years) plantations in northern Ontario. These SI curves were different from those for natural stands. Jack pine plantations had a higher site quality (SI) than did the original natural stands on the similar sites. The SI curves developed from natural stands should not be used to predict growth and yield of jack pine plantations before they are calibrated for jack pine plantations. These GI models will be used to estimate SI for silviculture and forest-management planning.
Relationships between deer mice and downed wood in managed forests of southern British Columbia
Authors: Craig Vanessa J , Klenner Walt , Feller Michael C , Sullivan Thomas P
Published: October 2006

We examined the relationship between deer mice (Peromyscus maniculatus (Wagner)) and downed wood in a low-elevation Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) forest and a high-elevation Engelmann spruce (Picea engelmannii Parry ex Engelm.)  subalpine fir (Abies lasiocarpa (Hook.) Nutt.) forest in the south-central interior of British Columbia. We experimentally manipulated the volume of downed wood on clear-cut and forested sites and monitored the response of deer mice with a markrecapture study to assess population densities and survival and reproduction rates. Populations responded positively to harvesting at the low-elevation but not the high-elevation study area. At the low-elevation study area, the population dynamics of deer mice on clear-cut and forested treatments were not positively associated with patterns of vegetation cover or increasing downed-wood volumes. Instead, populations on clearcuts appeared to increase in response to an unknown factor associated with lower volumes. No relationship was detected between population dynamics of deer mice and downed-wood volumes at the high-elevation site. The population dynamics of deer mice on forests at the high-elevation site appeared to be more closely related to vegetation cover than to downed wood. The results indicated that downed wood is not a critical habitat component for deer mice in the south-central interior of British Columbia.
Soil carbon and nitrogen pools in mid- to late-successional forest stands of the northwestern United States: potential impact of fire
Authors: Page-Dumroese Deborah S , Jurgensen Martin F
Published: October 2006

When sampling woody residue (WR) and organic matter (OM) present in forest floor, soil wood, and surface mineral soil (0–30 cm) in 14 mid- to late-successional stands across a wide variety of soil types and climatic regimes in the northwestern USA, we found that 44%–84% of carbon (C) was in WR and surface OM, whereas >80% of nitrogen (N) was in the mineral soil. In many northwestern forests fire suppression and natural changes in stand composition have increased the amounts of WR and soil OM susceptible to wildfire losses. Stands with high OM concentrations on the soil surface are at greater risk of losing large amounts of C and N after high-severity surface fires. Using the USDA Forest Service Regional Soil Quality Standards and Guidelines, we estimate that 6%–80% of the pooled C to a mineral-soil depth of 30 cm could be lost during a fire considered detrimental to soil productivity. These estimates will vary with local climatic regimes, fire severity across the burned area, the size and decay class of WR, and the distribution of OM in the surface organic and mineral soil. Estimated N losses due to fire were much lower (<1%–19%). Further studies on the amounts and distribution of OM in these stands are needed to assess wildfire risk, determine the impacts of different fire severities on WR and soil OM pools, and develop a link between C and N losses and stand productivity.
Can forest management based on natural disturbances maintain ecological resilience?
Authors: Drever C Ronnie , Peterson Garry , Messier Christian , Bergeron Yves , Flannigan Mike
Published: October 2006

Given the increasingly global stresses on forests, many ecologists argue that managers must maintain ecological resilience: the capacity of ecosystems to absorb disturbances without undergoing fundamental change. In this review we ask: Can the emerging paradigm of natural-disturbance-based management (NDBM) maintain ecological resilience in managed forests? Applying resilience theory requires careful articulation of the ecosystem state under consideration, the disturbances and stresses that affect the persistence of possible alternative states, and the spatial and temporal scales of management relevance. Implementing NDBM while maintaining resilience means recognizing that (i) biodiversity is important for long-term ecosystem persistence, (ii) natural disturbances play a critical role as a generator of structural and compositional heterogeneity at multiple scales, and (iii) traditional management tends to produce forests more homogeneous than those disturbed naturally and increases the likelihood of unexpected catastrophic change by constraining variation of key environmental processes. NDBM may maintain resilience if silvicultural strategies retain the structures and processes that perpetuate desired states while reducing those that enhance resilience of undesirable states. Such strategies require an understanding of harvesting impacts on slow ecosystem processes, such as seed-bank or nutrient dynamics, which in the long term can lead to ecological surprises by altering the forest's capacity to reorganize after disturbance.
BOLD-MRI assessment of intrarenal oxygenation and oxidative stress in patients with chronic kidney allograft dysfunction
Authors: Djamali Arjang , Sadowski Elizabeth A. , Muehrer Rebecca J. , Reese Shannon , Smavatkul Chanigan , Vidyasagar Aparna , Fain Sean B. , Lipscomb Ryan C. , Hullett Debra H. , Samaniego-Picota Millie , Grist Thomas M. , Becker Bryan N.
Published: October 2006

Blood oxygen level-dependent (BOLD) magnetic resonance imaging (MRI) uses deoxyhemoglobin as an endogenous contrast agent for the noninvasive assessment of tissue oxygen bioavailability. We hypothesized that intrarenal oxygenation was impaired in patients with chronic allograft nephropathy (CAN). Ten kidney-transplant recipients with CAN and nine healthy volunteers underwent BOLD-MRI. Medullary R2* (MR2*) and cortical R2* (CR2*) levels (measures directly proportional to tissue deoxyhemoglobin levels) were determined alongside urine and serum markers of oxidative stress (OS): hydrogen peroxide (H2O2), F2-isoprostanes, total nitric oxide (NO), heat shock protein 27 (HSP27), and total antioxidant property (TAOP). Mean MR2* and CR2* levels were significantly decreased in CAN (increased local oxyhemoglobin concentration) compared with healthy volunteers (20.7 ± 1.6 vs. 23.1 ± 1.8/s, P = 0.03 and 15.9 ± 1.9 vs. 13.6 ± 2.3/s, P = 0.05, respectively). There was a significant increase in serum and urine levels of H2O2and serum HSP27 levels in patients with CAN. Conversely, urine NO levels and TAOP were significantly increased in healthy volunteers. Multiple linear regression analyses showed a significant association between MR2* and CR2* levels and serum/urine biomarkers of OS. BOLD-MRI demonstrated significant changes in medullary and cortical oxygen bioavailability in allografts with CAN. These correlated with serum/urine biomarkers of OS, suggesting an association between intrarenal oxygenation and OS.
BOLD Adaptation in Vibrotactile Stimulation: Neuronal Networks Involved in Frequency Discrimination
Authors: Li Hegner Yiwen , Saur Ralf , Veit Ralf , Butts Raymond , Leiberg Susanne , Grodd Wolfgang , Braun Christoph
Published: October 2006

The present functional magnetic resonance imaging (fMRI) study investigated human brain regions subserving the discrimination of vibrotactile frequency. An event-related adaptation paradigm was used in which blood-oxygen-level-dependent (BOLD) responses are lower to same compared with different pairs of stimuli (BOLD adaptation). This adaptation effect serves as an indicator for feature-specific responding of neuronal subpopulations. Subjects had to discriminate two vibrotactile stimuli sequentially applied with a delay of 600 ms to their left middle fingertip. The stimulus frequency was in the flutter range of 18–26 Hz. In half of the trials, the two stimuli possessed identical frequency (same), whereas in the other half, a frequency difference of ±2 Hz was used (diff). As a result, BOLD adaptation was observed in the contralateral primary somatosensory cortex (S1), precentral gyrus, superior temporal gyrus (STG); ipsilateral insula as well as bilateral secondary somatosensory cortex and supplementary motor area. When statistically comparing the BOLD time courses between same and diff trials in these cortical areas, it was found that the vibrotactile BOLD adaptation is initiated in the contralateral S1 and STG simultaneously. These findings suggest that the cortical areas responsive to the frequency difference between two serially presented stimuli sequentially process the frequency of a vibrotactile stimulus and constitute a putative neuronal network underlying human vibrotactile frequency discrimination.
Molecular characterization and association analysis of porcine CA3
Authors: Wang H.L. , Zhu Z.M. , Wang H. , Yang S.L. , Zhao S.H. , Li K.
Published: October 2006

Carbonic anhydrase 3 (CA3) is a member of the carbonic anhydrase family, which plays an important role in various cell processes. In this paper, molecular characterization revealed that CA3 genomic DNA consists of seven exons and six introns, spans about 10.5 kb and maps to porcine chromosome 4q11→q14. Results of expression profiles showed that the expression levels of CA3 increased in skeletal muscles from prenatal 33- to 65-day-old Chinese Tongcheng pigs. These levels subsequently decreased to a steady state in prenatal 90-day-old, postnatal 2-day-old, postnatal 28-day-old, and pregnant 65-day-old pigs. The expression patterns of Chinese Tongcheng pig embryos were different from that of Landrace pig embryos. CA3 was expressed at higher levels in skeletal muscle and liver than in kidney, lung, stomach, intestine, and brain, but was not detected in heart and spleen. Statistical analysis showed the CA3 gene polymorphism was different between Chinese indigenous and introduced commercial western pig breeds, and was associated with intramuscular fat content and percentage of ham of pigs.
Cytogenetic characterization of alpaca (Lama pacos, fam. Camelidae) prometaphase chromosomes
Authors: Di Berardino D. , Nicodemo D. , Coppola G. , King A.W. , Ramunno L. , Cosenza G.F. , Iannuzzi L. , Di Meo G.P. , Balmus G. , Rubes J.
Published: October 2006

The present study provides specific cytogenetic information on prometaphase chromosomes of the alpaca (Lama pacos, fam. Camelidae, 2n = 74) that forms a basis for future work on karyotype standardization and gene mapping of the species, as well as for comparative studies and future genetic improvement programs within the family Camelidae. Based on the centromeric index (CI) measurements, alpaca chromosomes have been classified into four groups: group A, subtelocentrics, from pair 1 to 10; group B, telocentrics, from pair 11 to 20; group C, submetacentrics, from pair 21 to 29; group D, metacentrics, from pair 30 to 36 plus sex chromosomes. For each chromosome pair, the following data are provided: relative chromosome length, centromeric index, conventional Giemsa staining, sequential QFQ/C-banding, GTG- and RBG-banding patterns with corresponding ideograms, RBA-banding and sequential RBA/silver staining for NOR localization. The overall number of RBG-bands revealed was 391. Nucleolus organizer-bearing chromosomes were identified as pairs 6, 28, 31, 32, 33 and 34. Comparative ZOO-FISH analysis with camel (Camelus dromedarius) X and Y painting probes was also carried out to validate X-Y chromosome identification of alpaca and to confirm close homologies between the sex chromosomes of these two species.
Karyotype relationships of six bat species (Chiroptera, Vespertilionidae) from China revealed by chromosome painting and G-banding comparison
Authors: Ao L. , Gu X. , Feng Q. , Wang J. , O’Brien P.C.M. , Fu B. , Mao X. , Su W. , Wang Y. , Volleth M. , Yang F. , Nie W.
Published: October 2006

The Vespertilionidae is the largest family in the order Chiroptera and has a worldwide distribution in the temperate and tropical regions. In order to further clarify the karyotype relationships at the lower taxonomic level in Vespertilionidae, genome-wide comparative maps have been constructed between Myotis myotis (MMY, 2n = 44) and six vesper bats from China: Myotis altarium (MAL, 2n = 44), Hypsugo pulveratus (HPU, 2n = 44), Nyctalus velutinus (NVE, 2n = 36), Tylonycteris robustula (TRO, 2n = 32), Tylonycteris sp. (TSP, 2n = 30)and Miniopterus fuliginosus (MFU, 2n = 46) by cross-species chromosome painting with a set of painting probes derived from flow-sorted chromosomes of Myotis myotis. Each Myotis myotis autosomal probe detected a single homologous chromosomal segment in the genomes of these six vesper bats except for MMY chromosome 3/4 paint which hybridized onto two chromosomes in the genome of M. fuliginosus. Our results show that Robertsonian translocation is the main mode of karyotype evolution in Vespertilionidae and that the addition of heterochromatic material also plays an important role in the karyotypic evolution of the genera Tylonycteris and Nyctalus. Two conserved syntenic associations (MMY9 + 23 and 18 + 19) could be the synapomorphic features for the genus Tylonycteris. The integration of our maps with the published maps has enabled us to deduce chromosomal homologies between human and these six vesper bats and provided new insight into the karyotype evolution of the family Vespertilionidae.
Non-telomeric sites as evidence of chromosomal rearrangement and repetitive (TTAGGG)n arrays in heterochromatic and euchromatic regions in four species of Akodon (Rodentia, Muridae)
Authors: Ventura K. , Silva M.J.J. , Fagundes V. , Christoff A.U. , Yonenaga-Yassuda Y.
Published: October 2006

Comparative studies among four species – Akodonazarae (2n = 38), A. lindberghi (2n = 42), A. paranaensis (2n = 44) and A. serrensis (2n = 46) – employing classic cytogenetics (C- and G-bands) and fluorescence in situ hybridization with telomeric (TTAGGG)n sequencesare reported here. Non-telomeric signals in addition to the regular telomeric sites were detected in three species:A. azarae, A. lindberghi and A. serrensis. One interstitial telomeric site (ITS) was observed proximally at the long arm of chromosome 1 of A. azarae. The comparison of G-banding patterns among the species indicated that the ITS was due to a tandem fusion/fission rearrangement. Non-telomeric signals of A. lindberghi and A. serrensis were not related to chromosomal rearrangements; instead, the sequences co-localized with (i) heterochromatic regions of all chromosomes in A. serrensis; (ii) some heterochromatic regions in A. lindberghi, and (iii) both euchromatic and heterochromatic regions in the metacentric pair of A. lindberghi. These exceptional findings revealed that ITS in Akodon can be related to chromosomal rearrangements and repetitive sequences in the constitutive heterochromatin and that the richness of TTAGGG-like sequences in the euchromatin could be hypothesized to be a result of amplification of the referred sequence along the chromosome arms.
Characterization of the porcine FSCN3 gene: cDNA cloning, genomic structure, mapping and polymorphisms
Authors: Kollers S. , Day A. , Rocha D.
Published: October 2006

Fascin 3 (FSCN3)is a testis-specific actin-bundling protein involved in spermatid development. Here we describe the molecular characterisation of the porcine FSCN3 gene. The 1,800-bp cDNA sequence contains a 1,497-bp open reading frame encoding a protein of 498 amino acids with a calculated molecular mass of 56.2 kDa and an isoelectric point of 6.82. The porcine FSCN3 protein shares high identity with other mammalian FSCN3. The FSCN3 gene contains seven exons, spans approximately 9 kb, and maps to pig chromosome 18. We also identified 24 DNA polymorphisms.
A Finite Element Model of the Human Head for Auditory Bone Conduction Simulation
Authors: Taschke Henning , Hudde Herbert
Published: October 2006

In order to investigate the mechanisms of bone conduction, a finite element model of the human head was developed. The most important steps of the modelling process are described. The model was excited by means of percutaneously applied forces in order to get a deeper insight into the way the parts of the peripheral hearing organ and the surrounding tissue vibrate. The analysis is done based on the division of the bone conduction mechanisms into components. The frequency-dependent patterns of vibration of the components are analyzed. Furthermore, the model allows for the calculation of the contribution of each component to the overall bone-conducted sound. The components interact in a complicated way, which strongly depends on the nature of the excitation and the spatial region to which it is applied.
How Does the Inner Ear Generate Distortion Product Otoacoustic Emissions?
Authors: Vetesnik Ales , Nobili Renato , Gummer Anthony
Published: October 2006

There is general agreement that distortion product (DP) otoacoustic emissions elicited by stimuli up to 80–90 dB SPL originate from the saturating nonlinearity of the cochlear amplifier at the basilar membrane site, S, where the responses to the two primary tones overlap. There are, however, different interpretations of how the inner ear transmits the effects of this process to the stapes. The supporters of transmission line models assert that the phenomenon depends upon two main mechanisms: (1) the generation of forward and backward traveling waves (TWs) by DP oscillations at S; (2) the backward propagation of wave components reflected by ‘micromechanical impedance perturbations’ at the sites where the DP TWs peak. However, quantitative predictions based on this view are still lacking. In contrast, here we show, using a nonlinear hydrodynamic model, that the emissions are propagated almost instantaneously through the fluid.
Mechanical Preprocessing of Amplitude-Modulated Sounds in the Apex of the Cochlea
Authors: Cooper Nigel P.
Published: October 2006

Sound-evoked vibrations of individual Hensen’s cells in the apical turn of a living guinea pig cochlea were recorded using a displacement-sensitive laser interferometer. The mechanical responses to amplitude-modulated (AM) tones were investigated, and are shown to be physiologically vulnerable. In the healthy cochlea, the AM responses are demodulated strongly at both moderate and high sound pressure levels. In the less healthy and postmortem cochlea, AM demodulation is weaker and is only seen at high stimulus levels. The physiologically vulnerable component of the demodulation is considered to be an analogue of the baseline position shifts that can be seen in the apical cochlea’s responses to pure-tone stimuli, and is likely to originate in the cellular motility of the cochlea’s outer hair cells.
Benign Paroxysmal Positioning Vertigo: A Disease Explainable by Inner Ear Mechanics
Authors: Hamann Karl-Friedrich
Published: October 2006

Many arguments give evidence that benign paroxysmal positioning vertigo, one of the most frequent kinds of vertigo, can be reduced to mechanical processes in the vestibular part of the labyrinth. Based on the assumption that otoliths have departed from their normally fixed position in the otolithic membrane and travel in the semicircular canals, clinical observations find their explanation. Latency between the onset of a head movement and the beginning of the vertiginous sensation, its duration and the nystagmic pattern provoked by specific head movements are in good correlation with the canalith hypothesis. Further arguments are the successful treatment by liberatory maneuvers, the relatively high number of recurrences and the change of the affected canal.
Recurrence of Stress-Induced (Takotsubo) Cardiomyopathy
Authors: Cherian John , Angelis Dimitrios , Filiberti Allen , Saperia Gordon
Published: October 2006

Takotsubo cardiomyopathy is a recently recognized form of transient left ventricular dysfunction that is presumably precipitated by stress and may clinically resemble an acute coronary syndrome. These patients have an akinetic left ventricular apex in an unusual shape that resembles a takotsubo. Although reports of single episodes of takotsubo cardiomyopathy are not infrequent in recent medical literature, we report a case of recurrence that may provide more insight into the nature of this syndrome.
Gamma Knife Radiosurgery for Epilepsy Related to Dysembryoplastic Neuroepithelial Tumor
Authors: Kwon Ki-Hun , Lee Jung-Il , Hong Seung-Chyul , Seo Dae Won , Hong Seung Bong
Published: October 2006

Dysembryoplastic neuroepithelial tumor (DNT) is a well-known epileptogenic lesion with favorable seizure outcome after surgical resection. However, sometimes surgery may be difficult technically, and epilepsy may continue throughout the patient’s lifetime despite surgical intervention. We report a case of intractable epilepsy related to DNT that was treated with gamma knife radiosurgery (GKRS). The frequency of seizure was reduced remarkably after GKRS, and finally a seizure-free state was accomplished in two years. Neuropsychological tests also showed improvement. It is suggested that GKRS may be an effective and less invasive alternative treatment for the patients in whom surgical treatment is difficult.
The Relationship of Reactive Psychosis and ICD-10 Acute and Transient Psychotic Disorders: Evidence from a Case Register-Based Comparison
Authors: Castagnini Augusto , Bertelsen Aksel , Munk-Jørgensen Povl , Berrios German E.
Published: October 2006

Background: ICD-10 introduced a new diagnostic category, F23 ‘acute and transient psychotic disorders’ (ATPD), to embrace clinical concepts such as bouffée délirante, cycloid psychosis, psychogenic (reactive) psychosis and schizophreniform psychosis. The purpose of this study was to examine the relationship between the concept of reactive psychosis (RP), equivalent to the ICD-8 298 category of ‘other psychoses’, and ATPD. Sampling and Method: Since January 1, 1994, ICD-10 has replaced ICD-8 as official classification in Denmark. Patients given an ICD-8 298 diagnosis on their last admission in 1992–1993 were identified from the Danish Psychiatric Central Register, and the ICD-8 diagnoses assigned were compared with their ICD-10 diagnoses when readmitted in 1994–1995. Results: Diagnosis of RP was recorded in 19.2% of patients with functional psychoses in 1992–1993, whereas ATPD overall prevalence accounted for 8.7% of those with non-organic psychotic and affective disorders in 1994–1995. Thirty-eight per cent of patients with an ICD-8 298 diagnosis were readmitted during the years 1994–1995. Schizophrenia and related disorders (F2) and affective disorders (F3) accounted for three quarters of ICD-10 diagnoses. The most frequently used ATPD subcategories were F23.3 ‘other acute delusional psychotic disorders’, F23.0 ‘acute polymorphic psychotic disorder without symptoms of schizophrenia’ and F23.9 ‘acute and transient psychotic disorder unspecified’. A significant majority were female and associated acute stress was recorded only in 5.3% of cases. Conclusions: ICD-8 298 register diagnosis of RP showed little empirical continuity to ATPD and conformed more to F23.3 acute delusional disorder among ATPD subtypes.
Benefits of Candesartan on Arterial and Renal Damage of Non-Diabetic Hypertensive Patients Treated with Calcium Channel Blockers
Authors: Ichihara Atsuhiro , Kaneshiro Yuki , Takemitsu Tomoko , Sakoda Mariyo , Itoh Hiroshi
Published: October 2006

Background/Aim: Although long-term, intensive blood pressure (BP) control with calcium channel blockers (CCBs) reduced arterial stiffness and renal damage of hypertensive patients, combination therapy with antihypertensive drugs is frequently needed to maintain the intensive BP control. The present study was conducted to examine add-on benefits of candesartan therapy on hypertensive patients treated with CCBs for at least 12 months. Methods: Pulse wave velocity (PWV), urinary albumin excretion (UAE), intima-media thickness (IMT) of the carotid arteries, and 24-hour ambulatory BP were determined in 50 non-diabetic hypertensive patients treated with CCBs before and 12 months after the start of therapy with candesartan or placebo. Results: Candesartan significantly decreased clinic BP and tended to decrease ambulatory BP, but the decreases were similar to those in the placebo group except nocturnal BP decrease, which was significantly enhanced by candesartan. Add-on candesartan significantly decreased PWV and UAE compared to placebo, but IMT was unchanged with candesartan or placebo. The decrease in clinic BP or nocturnal BP decrease did not contribute to the improvement of PWV or UAE. Conclusion: Add-on candesartan functionally improved the stiffened arteries of hypertensive patients treated with CCBs by the end of 12 months of treatment independently of its effects on BPs.
Effect of Naringenin on Intracerebroventricular Streptozotocin-Induced Cognitive Deficits in Rat: A Behavioral Analysis
Authors: Baluchnejadmojarad Tourandokht , Roghani Mehrdad
Published: October 2006

Intracerebroventricular (ICV) injection of streptozotocin (STZ) causes cognitive impairment in rats. The beneficial effect of naringenin (NAR) was investigated on ICV STZ-induced learning, memory, and cognitive impairment in male rats. For this purpose, rats were injected with ICV STZ bilaterally, on days 1 and 3 (3 mg/kg). The STZ-injected rats received NAR (50 mg/kg/day p.o.) starting 1 day pre-surgery for 3 weeks. The learning and memory performance was assessed using passive avoidance paradigm, and for spatial cognition evaluation, radial eight-arm maze (RAM) task was used. It was found out that NAR-treated STZ-injected rats show higher correct choices and lower errors in RAM than vehicle-treated STZ-injected rats. In addition, NAR administration significantly attenuated learning and memory impairment in treated STZ-injected group in passive avoidance test. Therefore, these results demonstrate the effectiveness of NAR in preventing the cognitive deficits caused by ICV STZ in rats and its potential in the treatment of neurodegenerative diseases such as Alzheimer’s disease.
Effect of Variables in Inert Gas Condensation Processing on Nanoparticle Trajectory Simulated by Finite Volume Method
Authors: Lee Kwang-Min , Juhng Woo-Nam , Choi Bo-Young
Published: October 2006

The finite volume method was applied to the determination of the three-dimensional convection current during inert gas condensation (IGC) processing by using the commercially available software, "Fluent." The lower velocity of the convection current at higher evaporation temperature
resulted from the lower value of the coefficient of thermal expansion. The velocity of the convection current increased with increasing chamber pressure, because the driving force of the buoyancy was directly proportional to the gas density. 13% and 17.3% of the particles were trapped during
the first period of circulation in the case of the single and double heaters, respectively.
Fabrication of Nanostructure and Formation of Nanocrystal for Non-Volatile Memory
Authors: Jung Sungwook , Parm I. O. , Jang Kyung Soo , Park Dae-Ho , Sohn Byeong-Hyeok , Jung Jin Chul , Zin Wang Cheol , Choi Suk-Ho , Dhungel S. K. , Yi J.
Published: October 2006

In this work, we have demonstrated that the nanocrystal created by combining the self-assembled block copolymer thin film with regular semiconductor processing can be applicable to non-volatile memory device with increased charge storage capacity over planar structures. Self-assembled
block copolymer thin film for nanostructures with critical dimensions below photolithographic resolution limits has been used during all experiments. Nanoporous thin film from PS-b-PMMA diblock copolymer thin film with selective removal of PMMA domains was used to fabricate nanostructure
and nanocrystal. We have also reported about surface morphologies and electrical properties of the nano-needle structure formed by RIE technique. The details of nanoscale pattern of the very uniform arrays using RIE are presented. We fabricated different surface structure of nanoscale using
block copolymer. We also deposited Si-rich SiNx layer using ICP-CVD on the silicon surface of nanostructure. The deposited films were studied after annealing. PL studies demonstrated nanocrystal in Si-rich SiNx film on nanostructure of silicon.
Anxiety and Identity in the Language Classroom
Authors: Stroud Christopher , Wee Lionel
Published: October 2006

While ELT has long recognized the need to address student anxiety in language learning situations, it has all too often assumed that such anxiety is primarily competence-based. Consequently, there has been insufficient recognition of the fact that identity-based anxiety, too, can have significant effects on language learning in the classroom. In this paper, we discuss some examples of identity-based anxiety, and argue that it requires a different approach to language teaching. We propose one such possible approach, which we call ‘double-crossing’.
MUC1 expression and anti-MUC1 serum immune response in head and neck squamous cell carcinoma (HNSCC): a multivariate analysis
Authors: Rabassa Martín E , Croce María V , Pereyra Adrián , Segal-Eiras Amada
Published: October 2006

Background

HNSCC progression to adjacent tissue and nodes may be mediated by altered glycoproteins and glycolipids such as MUC1 mucin. This report constitutes a detailed statistical study about MUC1 expression and anti-MUC1 immune responses in relation to different clinical and pathological parameters which may be useful to develop new anti HNSCC therapeutic strategies.

Patients and methods

Fifty three pre treatment HNSCC patients were included: 26 (49.1%) bearing oral cavity tumors, 17 (32.1%) localized in the larynx and 10 (18.8%) in the pharynx. Three patients (5.7%) were at stage I, 5 (9.4%) stage II, 15 (28.3%) stage III and 30 (56.6%) at stage IV. MUC1 tumor expression was studied by immunohistochemistry employing two anti-MUC1 antibodies: CT33, anti cytoplasmic tail MUC1 polyclonal antibody (Ab) and C595 anti-peptidic core MUC1 monoclonal antibody. Serum levels of MUC1 and free anti-MUC1 antibodies were detected by ELISA and circulating immune complexes (CIC) by precipitation in polyethylene glycol (PEG) 3.5%; MUC1 isolation from circulating immune complexes was performed by protein A-sepharose CL-4B affinity chromatography followed by SDS-PAGE and Western blot. Statistical analysis consisted in Multivariate Principal Component Analysis (PCA); ANOVA test (Tukey's test) was employed to find differences among groups; nonparametrical correlations (Kendall's Tau) were applied when necessary. Statistical significance was set to p < 0.05 in all cases.

Results

MUC1 cytoplasmic tail was detected in 40/50 (80%) and MUC1 protein core in 9/50 (18%) samples while serum MUC1 levels were elevated in 8/53 (15%) patients. A significant statistical correlation was found between MUC1 serum levels and anti-MUC1 IgG free antibodies, while a negative correlation between MUC1 serum levels and anti-MUC1 IgM free antibodies was found. Circulating immune complexes were elevated in 16/53 (30%) samples and were also statistically associated with advanced tumor stage. MUC1 was identified as an antigenic component of IgG circulating immune complexes. Moreover, poorly differentiated tumors were inversely correlated with tumor and serum MUC1 detection and positively correlated with node involvement and tumor mass.

Conclusion

Possibly, tumor cells produce MUC1 mucin which is liberated to the circulation and captured by IgG antibodies forming MUC1-IgG-CIC. Another interesting conclusion is that poorly differentiated tumors are inversely correlated with tumor and serum MUC1 detection.
Evaluation of the activity of CYP2C19 in Gujrati and Marwadi subjects living in Mumbai (Bombay)
Authors: Panchabhai Tanmay S , Noronha Shaun F , Davis Sanish , Shinde Vishal M , Kshirsagar Nilima A , Gogtay Nithya J
Published: October 2006

Background

Inherited differences in the metabolism and disposition of drugs, and genetic polymorphisms in the targets of drug therapy (e.g., receptors), can greatly influence efficacy and toxicity of medications. Marked interethnic differences in CYP2C19 (a member of the cytochrome P-450 enzyme superfamily catalyzing phase I drug metabolism) which affects the metabolism of a number of clinically important drugs have been documented. The present study evaluated the activity of CYP2C19 in normal, healthy Gujrati and Marwadi subjects by phenotyping (a western Indian population).

Methods

All subjects received 20 mg of omeprazole, which was followed by blood collection at 3 hrs to estimate the metabolic ratio of omeprazole to 5-hydroxyomeprazole. The analysis was done by HPLC.

Results

It was seen that 10.36% of this population were poor metabolizers(PM) whereas 89.63% were extensive metabolizers(EM).

Conclusion

A genotyping evaluation would better help in identifying population specific genotypes and thus help individualize drug therapy.
Preliminary data on Pemphigus vulgaris treatment by a proteomics-defined peptide: a case report
Authors: Angelini Giovanni , Bonamonte Domenico , Lucchese Alberta , Favia Gianfranco , Serpico Rosario , Mittelman Abraham , Simone Simone , Sinha Animesh A , Kanduc Darja
Published: October 2006

Background

Although described by Hippocrates in 400 B.C., pemphigus disease still needs a safe therapeutical approach, given that the currently used therapies (i.e. corticosteroids and immunosuppressive drugs) often provoke collateral effects. Here we present preliminary data on the possible use of a proteomics derived desmoglein peptide which appears promising in halting disease progression without adverse effects.

Methods

The low-similarity Dsg349–60REWVKFAKPCRE peptide was topically applied for 1 wk onto a lesion in a patient with a late-stage Pemphigus vulgaris (PV) complicated by diabetes and cataract disease. The peptide was applied as an adjuvant in combination with the standard corticosteroid-based immunosuppressive treatment.

Results

After 1 wk, the treated PV eroded lesion appeared dimensionally reduced and with an increased rate of re-epithelization when compared to adjacent non-treated lesions. Short-term benefits were: decrease of anti-Dsg antibody titer and reduction of the corticosteroid dosage. Long-term benefits: after two years following the unique 1-wk topical treatment, the decrease of anti-Dsg antibody titer persists. The patient is still at the low cortisone dosage. Adverse effects: no adverse effect could be monitored.

Conclusion

With the limits inherent to any preliminary study, this case report indicates that topical treatment with Dsg349–60REWVKFAKPCRE peptide may represent a feasible first step in the search for a simple, effective and safe treatment of PV.