bluuebunny/crossref_metadata_2025 huggingface dataset:
Bcl-xIs Required for Proper Development of the Mouse Substantia Nigra
Authors: Savitt Joseph M. , Jang Susie S. , Mu Weitong , Dawson Valina L. , Dawson Ted M.
Published: July 2005

Recent findings have uncovered a role for theBcl-xgene in the survival of dopaminergic neurons. The exact nature of this role has been difficult to examine because of the embryonic lethality ofBcl-xgene disruption in mouse models. Here we report the generation catecholaminergic cell-specific conditionalBcl-xgene knock-out mice using Cre-lox recombination technology. First we produced transgenic mice that express Cre recombinase from an exogenous rat tyrosine hydroxylase promoter (TH-Cremice). These mice were crossed toZ/APandZ/EGreporter mouse strains to verify catecholaminergic (TH-positive) cell-specific Cre expression. TheTH-Cremice then were mated to mice possessing theBcl-xgene flanked by loxP sites, thereby producing offspring withBcl-xdeletion limited to catecholaminergic cells. The resulting mice are viable but have one-third fewer catecholaminergic neurons than do control animals. They demonstrate a deficiency in striatal dopamine and also tend to be smaller and have decreased brain mass when compared with controls. Surprisingly, surviving neurons were found that lacked Bcl-x immunoreactivity, thereby demonstrating that this gene is dispensable for the ongoing survival of a subpopulation of catecholaminergic cells.
Synaptically Driven Endocannabinoid Release Requires Ca2+-Assisted Metabotropic Glutamate Receptor Subtype 1 to Phospholipase C β4 Signaling Cascade in the Cerebellum
Authors: Maejima Takashi , Oka Saori , Hashimotodani Yuki , Ohno-Shosaku Takako , Aiba Atsu , Wu Dianqing , Waku Keizo , Sugiura Takayuki , Kano Masanobu
Published: July 2005

Endocannabinoids mediate retrograde signaling and modulate synaptic transmission in various regions of the CNS. Depolarization-induced elevation of intracellular Ca2+concentration causes endocannabinoid-mediated suppression of excitatory/inhibitory synaptic transmission. Activation of Gq/11-coupled receptors including group I metabotropic glutamate receptors (mGluRs) also causes endocannabinoid-mediated suppression of synaptic transmission. However, precise mechanisms of endocannabinoid production initiated by physiologically relevant synaptic activity remain to be determined. To address this problem, we made whole-cell recordings from Purkinje cells (PCs) in mouse cerebellar slices and examined their excitatory synapses arising from climbing fibers (CFs) and parallel fibers (PFs). We first characterized three distinct modes to induce endocannabinoid release by analyzing CF to PC synapses. The first mode is strong activation of mGluR subtype 1 (mGluR1)-phospholipase C (PLC) β4 cascade without detectable Ca2+elevation. The second mode is Ca2+elevation to a micromolar range without activation of the mGluR1-PLCβ4 cascade. The third mode is the Ca2+-assisted mGluR1-PLCβ4 cascade that requires weak mGluR1 activation and Ca2+elevation to a submicromolar range. By analyzing PF to PC synapses, we show that the third mode is essential for effective endocannabinoid release from PCs by excitatory synaptic activity. Furthermore, our biochemical analysis demonstrates that combined weak mGluR1 activation and mild depolarization in PCs effectively produces 2-arachidonoylglycerol (2-AG), a candidate of endocannabinoid, whereas either stimulus alone did not produce detectable 2-AG. Our results strongly suggest that under physiological conditions, excitatory synaptic inputs to PCs activate the Ca2+-assisted mGluR1-PLCβ4 cascade, and thereby produce 2-AG, which retrogradely modulates synaptic transmission to PCs.
Neurogliaform Neurons Form a Novel Inhibitory Network in the Hippocampal CA1 Area
Authors: Price Christopher J. , Cauli Bruno , Kovacs Endre R. , Kulik Akos , Lambolez Bertrand , Shigemoto Ryuichi , Capogna Marco
Published: July 2005

We studied neurogliaform neurons in the stratum lacunosum moleculare of the CA1 hippocampal area. These interneurons have short stellate dendrites and an extensive axonal arbor mainly located in the stratum lacunosum moleculare. Single-cell reverse transcription-PCR showed that these neurons were GABAergic and that the majority expressed mRNA for neuropeptide Y. Most neurogliaform neurons tested were immunoreactive for α-actinin-2, and many stratum lacunosum moleculare interneurons coexpressed α-actinin-2 and neuropeptide Y. Neurogliaform neurons received monosynaptic, DNQX-sensitive excitatory input from the perforant path, and 40 Hz stimulation of this input evoked EPSCs displaying either depression or initial facilitation, followed by depression. Paired recordings performed between neurogliaform neurons showed that 85% of pairs were electrically connected and 70% were also connected via GABAergic synapses. Injection of sine waveforms into neurons during paired recordings resulted in transmission of the waveforms through the electrical synapse. Unitary IPSCs recorded from neurogliaform pairs readily fatigued, had a slow decay, and had a strong depression of the synaptic response at a 5 Hz stimulation frequency that was antagonized by the GABABantagonist (2S)-3-[[(1S)-1-(3,4-dichlorophenyl)ethyl]amino-2-hydroxypropyl](phenylmethyl) phosphinic acid (CGP55845). The amplitude of the first IPSC during the 5 Hz stimulation was also increased byCGP55845, suggesting a tonic inhibition of synaptic transmission. A small unitary GABAB-mediated IPSC could also be detected, providing the first evidence for such a component between GABAergic interneurons. Electron microscopic localization of the GABAB1subunit at neurogliaform synapses revealed the protein in both presynaptic and postsynaptic membranes. Our data disclose a novel interneuronal network well suited for modulating the flow of information between the entorhinal cortex and CA1 hippocampus.
Modulator Effects of Interleukin-1β and Tumor Necrosis Factor-α on AMPA-Induced Excitotoxicity in Mouse Organotypic Hippocampal Slice Cultures
Authors: Bernardino Liliana , Xapelli Sara , Silva Ana P. , Jakobsen Birthe , Poulsen Frantz R. , Oliveira Catarina R. , Vezzani Annamaria , Malva João O. , Zimmer Jens
Published: July 2005

The inflammatory cytokines interleukin-1β and tumor necrosis factor-α (TNF-α) have been identified as mediators of several forms of neurodegeneration in the brain. However, they can produce either deleterious or beneficial effects on neuronal function. We investigated the effects of these cytokines on neuronal death caused by exposure of mouse organotypic hippocampal slice cultures to toxic concentrations of AMPA. Either potentiation of excitotoxicity or neuroprotection was observed, depending on the concentration of the cytokines and the timing of exposure. A relatively high concentration of mouse recombinant TNF-α (10 ng/ml) enhanced excitotoxicity when the cultures were simultaneously exposed to AMPA and to this cytokine. Decreasing the concentration of TNF-α to 1 ng/ml resulted in neuroprotection against AMPA-induced neuronal death independently on the application protocol. By using TNF-α receptor (TNFR) knock-out mice, we demonstrated that the potentiation of AMPA-induced toxicity by TNF-α involves TNF receptor-1, whereas the neuroprotective effect is mediated by TNF receptor-2. AMPA exposure was associated with activation and proliferation of microglia as assessed by macrophage antigen-1 and bromodeoxyuridine immunohistochemistry, suggesting a functional recruitment of cytokine-producing cells at sites of neurodegeneration. Together, these findings are relevant for understanding the role of proinflammatory cytokines and microglia activation in acute and chronic excitotoxic conditions.
Nonauditory Events of a Behavioral Procedure Activate Auditory Cortex of Highly Trained Monkeys
Authors: Brosch Michael , Selezneva Elena , Scheich Henning
Published: July 2005

A central tenet in brain research is that early sensory cortex is modality specific, and, only in exceptional cases, such as deaf and blind subjects or professional musicians, is influenced by other modalities. Here we describe extensive cross-modal activation in the auditory cortex of two monkeys while they performed a demanding auditory categorization task: after a cue light was turned on, monkeys could initiate a tone sequence by touching a bar and then earn a reward by releasing the bar on occurrence of a falling frequency contour in the sequence. In their primary auditory cortex and posterior belt areas, we found many acoustically responsive neurons whose firing was synchronized to the cue light or to the touch or release of the bar. Of 315 multiunits, 45 exhibited cue light-related firing, 194 exhibited firing that was related to bar touch, and 268 exhibited firing that was related to bar release. Among 60 single units, we found one neuron with cue light-related firing, 21 with bar touch-related firing, and 36 with release-related firing. This firing disappeared at individual sites when the monkeys performed a visual detection task. Our findings corroborate and extend recent findings on cross-modal activation in the auditory cortex and suggests that the auditory cortex can be activated by visual and somatosensory stimulation and by movements. We speculate that the multimodal corepresentation in the auditory cortex has arisen from the intensive practice of the subjects with the behavioral procedure and that it facilitates the performance of audiomotor tasks in proficient subjects.
Split-Belt Treadmill Stepping in Infants Suggests Autonomous Pattern Generators for the Left and Right Leg in Humans
Authors: Yang Jaynie F. , Lamont Erin V. , Pang Marco Y. C.
Published: July 2005

The behavior of the pattern generator for walking in human infants (7-12 months of age) was studied by supporting the infants to step on a split-belt treadmill. The treadmill belts could be run at the same speed (tied-belt), different speeds, or in different directions (split-belt). We determined whether the legs could operate independently under these conditions, as demonstrated by taking different numbers of steps or by stepping in different directions. Video, surface electromyography, electrogoniometry, and force platform data were recorded. The majority of infants who could step under tied-belt conditions also stepped under split-belt conditions. During forward stepping at low speed differentials between the two belts (ratio, <4), infants adopted a step cycle duration that was intermediate between that expected from tied-belt stepping at each of the speeds. At large speed differentials between the two belts (ratio, 7-22), the infants took extra steps on the fast leg during the stance phase on the slow leg. When the two belts ran in opposite directions, one leg stepped forward, and the other stepped backward. During all forms of stepping, the legs maintained a reciprocal relationship, so that swing phase occurred in one leg at a time. Timing of muscle activity suggests a strong inhibition between the flexor-generating centers on each side and a weaker inhibition between the extensor-generating centers. The stepping behavior resembled that reported for other animals under similar conditions, suggesting that the pattern generator for each limb is autonomous but interacts with its counterpart for the contralateral limb.
Effects of Multiple Low-Head Dams on Fish, Macroinvertebrates, Habitat, and Water Quality in the Fox River, Illinois
Authors: Santucci Victor J. , Gephard Stephen R. , Pescitelli Stephen M.
Published: July 2005

We examined the effects of low-head dams on aquatic biota, habitat, and water quality in a 171-km reach of a midwestern warmwater river that was fragmented by 15 dams into a series of free-flowing and impounded habitats. Dams impounded 55% of the river's surface area within the study reach and influenced distributions of 30 species of fish by restricting upstream movements. Values for the Illinois index of biotic integrity (IBI) were higher in free-flowing areas (mean IBI = 46 out of a possible 60 at below-dam and midsegment free-flowing locations) than impounded areas (mean IBI < 31 for above-dam and midsegment impounded locations). Likewise, scores from a macroinvertebrate condition index (MCI) were higher at stations in free-flowing reaches (mean MCI > 415 out of a possible 700) than in nearshore areas of impounded reaches (mean MCI < 210). Ponar dredge samples taken only from open-water impounded areas showed an offshore invertebrate community that consisted almost entirely of tolerant oligochaetes and chironomid larvae. Qualitative habitat evaluation index (QHEI) scores indicated good-quality habitat in free-flowing areas (mean QHEI > 70 out of a possible 100) and severely degraded habitat at impounded sites (mean QHEI < 45). In impounded reaches, dissolved oxygen and pH showed wide daily fluctuations (2.5–18.0 mg/L and 7.0–9.4 units) and often failed to meet Illinois water quality standards. In free-flowing portions of river, fluctuations in these parameters were less extreme and water quality standards typically were met. We found little evidence of cumulative effects of dams; however, our data suggest that low-head dams adversely affect warmwater stream fish and macroinvertebrate communities by degrading habitat and water quality and fragmenting the river landscape. These results should aid river managers and stakeholders in determining appropriate restoration practices (i.e., dam removal versus fish passage structures) for warmwater rivers and streams that contain low-head dams.
Effects of Waterbody Type and Management Actions on Bluegill Growth Rates
Authors: Porath Mark T. , Hurley Keith L.
Published: July 2005

Managers have conducted a number of activities to improve the growth rates of bluegill Lepomis macrochirus. However, attempts to compare the effectiveness of management actions often ignore basic differences in growth related to the type of water body in which populations reside. Bluegill age and growth data were collected from four different water body types in Nebraska between 1994 and 2001. Model analysis detected significant differences in the previous year's growth increments by water body type. When compared with other water body types, growth increments were greater in Sandhill lakes for age-2 and age-3 bluegills and mean length at capture was greater for age −6 and −7 bluegills. Several significant age × management activity interactions were detected within water body types. The application of supplemental feed and the absence of gizzard shad Dorosoma cepedianum increased bluegill growth increments in borrow and sand– gravel mining pits, while in flood control reservoirs, the presence of gizzard shad negatively impacted bluegill growth increments. Harvest regulation impacts were mixed in both of these water body types. Managers should recognize basic differences in growth patterns between water body types when determining which management actions should be implemented or when evaluating their success.
Spatial Habitat Dynamics Affecting Bluegill Abundance in Minnesota Bass–Panfish Lakes
Authors: Cross Timothy K. , McInerny Michael C.
Published: July 2005

A holistic approach to fisheries management requires an understanding of factors related to fish abundance over several spatial scales. We used geographic information systems to extract data describing habitat influences across three different spatial scales for a selected ecological class of Minnesota bass–panfish lakes (n = 113). These data were then analyzed by regression tree analysis to describe relationships between habitat and trap-net catch per effort (CPE) of bluegills Lepomis macrochirus. At the landscape scale of analysis, bluegill CPE increased among lakes with decreases in hydrologic connectivity (landscape position) and increases in geographic northing and easting gradients that corresponded to regional differences in geomorphology and edaphic characteristics. At the watershed–lake scale of analysis, a regression tree model with variables describing watershed area, cultivated land cover, forested land cover, and lake area explained 55% of the variation in bluegill CPE among lakes. At the site scale, a regression tree model with variables describing submerged plant cover and detritus substrates explained 57% of the variation in bluegill CPE among 72 sites spread among six lakes. However, much of the site-scale habitat influences on bluegill abundance was explained by broader landscape- and watershed-scale factors that influence the plant and bottom substrates in lakes. This study reinforces the importance of identifying habitat limitations and the influences of human activities at the landscape and watershed scales in addition to more commonly addressed site-scale habitat deficiencies.
Movements of Fluvial Bonneville Cutthroat Trout in the Thomas Fork of the Bear River, Idaho–Wyoming
Authors: Colyer Warren T. , Kershner Jeffrey L. , Hilderbrand Robert H.
Published: July 2005

The majority of interior subspecies of cutthroat trout Oncorhynchus clarkii have been extirpated from large rivers by anthropogenic activities that have fragmented habitats and introduced nonnative competitors. Selective pressures against migratory behaviors and main-stem river occupation, coupled with conservation strategies that isolate genetically pure populations above barriers, have restricted gene flow and prevented expression of the fluvial life history in many populations. Existing knowledge about the movements and home range requirements of fluvial cutthroat trout is, therefore, limited. Our objectives in this study were to (1) determine the extent of seasonal home ranges and mobility of Bonneville cutthroat trout O. c. utah (BCT) in the Thomas Fork and main-stem Bear River and (2) evaluate the role of a water diversion structure functioning as a seasonal migration barrier to fish movement. We implanted 55 BCT in the Thomas Fork of the Bear River, Idaho, with radio transmitters and located them bimonthly in 1999–2000 and weekly in 2000–2001. We found fish to be more mobile than previously reported. Individuals above the diversion barrier occupied substantially larger home ranges than those below the barrier (analysis of variance: P = 0.0003; median = 2,225 m above barrier; median = 500 m below barrier) throughout our study, and they moved more frequently (mean, 0.89 movements/contact; range, 0.57–1.00) from October 2000 through March 2001 than fish below the barrier (mean, 0.45 movements/contact; range, 0.00–1.00). During the spring of both years, we located radio-tagged fish in both upstream and neighboring tributaries as far as 86 km away from our study site. Our results document the existence of a fluvial component of BCT in the Bear River and its tributaries and suggest that successful efforts at conservation of these fish must focus on main-stem habitats and the maintenance of seasonal migration corridors.
Winter Ice Processes and Pool Habitat Associated with Two Types of Constructed Instream Structures
Authors: Barrineau Christina E. , Hubert Wayne A. , Dey Paul D. , Annear Thomas C.
Published: July 2005

There is little information on the winter features of salmonid habitats associated with constructed instream structures to provide guidance when planning habitat improvement projects. We assessed winter habitat features for trout of the genera Oncorhynchus and Salvelinus in pools associated with two types of instream structures constructed on a low-gradient reach of a mountain stream in western Wyoming with a mean wetted width of 6.4 m. Pool habitat was affected by temporal variability in ice formations from fall into winter. As surface ice and snow accumulated with the progression of winter, variation in ice formations was less frequent and winter habitat conditions became more stable. However, groundwater inflow that maintained water temperatures at 0.2–0.6°C in a portion of the study reach appeared to contribute to incomplete surface ice cover and variation in ice formations in pools through most of the winter. Hanging dams and anchor ice dams were the primary ice features that affected winter habitat in pools associated with constructed instream structures. Trout were observed in these pools in the fall but tended to abandon pools with variation in ice formations as winter progressed. The potential impacts of groundwater inflow and winter ice processes on trout habitat in pools associated with instream structures should be considered when planning habitat improvement projects.
Seasonal Response of Juvenile Atlantic Salmon to Experimental Hydropeaking Power Generation in Newfoundland, Canada
Authors: Scruton D. A. , Pennell C. J. , Robertson M. J. , Ollerhead L. M. N. , Clarke K. D. , Alfredsen K. , Harby A. , McKinley R. S.
Published: July 2005

Variable hydropower production leads to hydropeaking, which causes discharge fluctuations that are potentially harmful to aquatic organisms. In this study, an experimental approach was used to investigate hydropeaking effects and associated hydraulic and habitat conditions on the home range and movement of juvenile Atlantic salmon Salmo salar. Prior studies examined the responses of Atlantic salmon and brook trout Salvelinus fontinalis to experimental hydropeaking during summer and autumn. The present study focused on Atlantic salmon, involved more rapid and extreme discharge manipulation, and included winter experiments to reflect influences of reduced temperature, ice conditions, and seasonal differences in behavior and habitat selection. Experiments were conducted over a range in discharge (0.5–5.0 m3/s) that resulted in dramatic habitat changes in the wide, shallow, boulder-strewn study reach. Experiments were repeated in summer and winter; however, the winter range in discharge was narrower due to constraints on water release. Fish response was monitored using manual telemetry in both seasons, and fixed telemetry was used to monitor fine-scale diel winter movements. Atlantic salmon had larger home ranges and were more mobile during all flow conditions and over diel cycles in summer than in winter, and there was anecdotal evidence of stranding in isolated pools in summer. Stream morphology, in addition to the magnitude of discharge change, was an important determinant of the propensity to move. In our study, there were considerable refugia from increased velocity and dewatering, which may have reduced the need to move. In winter, fish remained relatively sedentary in comparison with the summer foraging period, and this behavior may increase the likelihood for dewatering, stranding, and freezing. A secondary concern with hydropeaking regimes is the energetic cost to fish of moving to find suitable habitats, and during summer this cost could affect stored energy reserves, which could, in turn, affect overwinter survival.
A Comparison of Passive Gears for Selective Yellow Perch Harvest
Authors: Mangan Matthew T. , Brown Michael L. , St. Sauver Todd R.
Published: July 2005

The success of trap-and-transfer operations is influenced by the ability to quickly collect target fish and transport them to a recipient body of water. We compared catch rates of two gear types (modified fyke nets and cloverleaf traps with and without light attractants) to determine the most effective capture method for harvesting small yellow perch Perca flavescens (age < 2) and reducing stress to transferred fish. Fyke nets captured more small yellow perch than cloverleaf traps; however, cloverleaf traps reduced the bycatch of black bullheads Ameiurus melas and large yellow perch (age > 2) and required less effort to set and retrieve. Unlike fyke nets, cloverleaf traps can also be placed in offshore locations, thereby increasing the number of fishable areas. Light attractants (incandescent lights and cyalume glowsticks) increased the catch rates of yellow perch in cloverleaf traps set at night. Incandescent lights increased catch rates in fyke nets, but cyalume glowsticks were not effective. Cloverleaf traps and light attractants help to improve the success of yellow perch collection methods by increasing daily catch, reducing the effort associated with sorting out bycatch, and reducing stress to transferred fish.
Homogenization of Fall-Run Chinook Salmon Gene Pools in the Central Valley of California, USA
Authors: Williamson Kevin S. , May Bernie
Published: July 2005

We assessed the population genetic structure and temporal stability of genetic diversity from 1999 to 2001 in collections of fall-run Chinook salmon Oncorhynchus tshawytscha in California's Central Valley. Tests for genotypic differentiation at seven microsatellite loci revealed few significant pairwise comparisons between samples from five hatchery populations and eight naturally spawning populations throughout the Central Valley that were separated by 50–350 km. All collections were genetically homogeneous and failed to cluster with their nearest geographic neighbors. Likewise, evaluation of temporal change in genetic diversity revealed few changes over the 3 years of the study. Our results suggest that fall-run Chinook salmon throughout the Central Valley comprise a genetically homogeneous population that has lower among-population genetic diversity than fall-run Chinook salmon populations examined elsewhere over similar geographic scales. The lack of genetic distinction and the lack of temporal differences in allele frequencies between hatchery and naturally spawning fish indicate that considerable gene flow occurs between fall-run Chinook salmon throughout the Central Valley. Due to the prevalence of off-site release of hatchery-reared juveniles and the history of interbasin hatchery transfers and stocking within the Central Valley, homogenization of Central Valley fall-run populations is most likely the result of hatchery practices for the past 140 years.
Factors That Limit Growth and Abundance of Rainbow Trout across Ecologically Distinct Areas of Flaming Gorge Reservoir, Utah–Wyoming
Authors: Haddix Tyler , Budy Phaedra
Published: July 2005

Rainbow trout Oncorhynchus mykiss stocked into Flaming Gorge Reservoir, Utah– Wyoming, are thought to be in poor condition and to rarely overwinter. In 2001–2002, we evaluated factors that affect the growth and abundance of rainbow trout, both temporally and spatially, based on a series of field measurements and growth experiments. Based on our field measurements, the growth and condition of rainbow trout in Flaming Gorge Reservoir actually parallel those of rainbow trout of various strains in other systems, and some rainbow trout overwinter as many as 3 years in the reservoir. Overall, rainbow trout appear to be spatially limited by physical factors (e.g., temperature) during only a few isolated times of the year and not in all areas of the reservoir. Although zooplankton were abundant throughout the reservoir, primary and secondary production vary spatially with concordant effects on fish growth and condition. Diet analysis indicated that rainbow trout consume primarily aquatic macroinvertebrates along with some zooplankton and demonstrate an extremely limited switch to piscivory at larger sizes. Rainbow trout reared in net-pens and limited to a diet of zooplankton lost weight in all three areas of the reservoir. In addition, the reservoir supports a large population of trophy lake trout Salvelinus namaycush, which probably affects the abundance of rainbow trout directly through consumption and the growth potential of rainbow trout indirectly through risk-averse behavior. The combination of spatial variation in reservoir productivity and habitat type, differing stocking strategies, and behavioral responses caused by predators appears to determine the varying success of stocked rainbow trout in the different areas of the reservoir. Our study suggests that stocking strategies may be most effective when specific characteristics of the prey and predator base, the suitability of different habitats, and the genetic strain are explicitly evaluated within the context of the targeted angler population.
Low Summer Water Temperatures Influence Occurrence of Naturalized Salmonids across a Mountain Watershed
Authors: Mullner Scott A. , Hubert Wayne A.
Published: July 2005

We investigated relationships between the absence of salmonids and low summer water temperatures across a 150-km2 Rocky Mountain watershed. A model predicting maximum July water temperature (MJT) from measurements of perennial stream length, wetted width, and midrange basin elevation was developed from temperature data obtained at 20 sites across the watershed. The model was used to predict MJT in 75 reaches across the watershed where salmonids were sampled. The lowest predicted MJT in reaches where age-0 and juvenile–adult brook trout Salvelinus fontinalis were observed was 9°C. The lowest predicted MJT in reaches where age-0 progeny of the genus Oncorhynchus spp. (i.e., rainbow trout O. mykiss or cutthroat trout O. clarkii) were observed was 13°C and where Oncorhynchus spp. adults where observed was 12°C. The probability of occurrence of both age-0 and adult brook trout and Oncorhynchus spp. increased as MJT increased above these thresholds. Our results indicate that low MJT in some portions of a mountain watershed can be related to the absence of salmonids. Consequently, data on MJT may provide managers with a means of assessing where summer water temperatures are not suitable for establishment of naturalized salmonid populations.
Planning Tools
Authors: Moller Chris
Published: July 2005

New forms of practice that respond to the changing role of the architect are now breaking through to reveal architecture as very much a process, contrary to the profession's 30‐year obsession with itself as object and surface. Much of the ground for this change was set in the 1970s. Now that the technology has arrived, Chris Moller talks about how the work of his own S333 epitomises the new breed of architect by addressing wider urban issues, engaging other disciplines in the design process and creating new tools with which to work. Copyright © 2005 John Wiley & Sons, Ltd.
Hmmmm Gardening… Some Comments on Garden Style and False Economy
Authors: Vincent Jon
Published: July 2005

Architects beware! Seized with your renewed vigour for ‘greening’ your schemes, you must know that there are plants, and there are plants, and that they should not be misinterpreted. Jon Vincent has strong opinions about how divisive some landscaping decisions can become, and incorporates these rules into his own, more responsive, garden designs. Copyright © 2005 John Wiley & Sons, Ltd.
Theatre Underground
Authors: Kellogg Craig
Published: July 2005

In New York, Craig Kellogg uncovers architect Beyer Blinder Belle's collaboration with production designer Klara Zieglerova and graphics firm 2×4 on a dramatic adaptive re‐use. Copyright © 2005 John Wiley & Sons, Ltd.
The Use of Sequential Extraction Procedures for the Characterization and Management of Contaminated Soils
Authors: Abollino Ornella , Giacomino Agnese , Malandrino Mery , Mentasti Edoardo
Published: July 2005

Metal mobility and availability in solid samples, such as soils, sediments and sludges, is frequently studied with sequential extraction procedures, which allow to partition the total metal content into classes of different reactivity. From the experimental point of view, each extraction step requires many practical operations, which can represent sources of error if they are not properly executed. The first part of the paper gives indication on how to perform sequential extractions, from sample pretreatment to extract analysis, in order to reduce experimental errors. The second part describes the main applications of sequential extraction schemes for the characterization and management of contaminated soils: the assessment of the risks associated to metal pollution, the evaluation of the feasibility and efficiency of remediation techniques, the study of soil properties and of metal behaviour and plant availability.
Nitrated Polycyclic Aromatic Hydrocarbons in the Environment: Formation, Occurrences and Analysis
Authors: Perrini Giancarlo , Tomasello Massimo , Librando Vito , Minniti Zelica
Published: July 2005

A review is presented on the formation and occurrence in the atmosphere of nitrated polycyclic aromatic hydrocarbons. Some analytical methodologies (covering various matrices) are also considered.
Fragile X syndrome
Authors: Terracciano Alessandra , Chiurazzi Pietro , Neri Giovanni
Published: July 2005

Fragile X syndrome, the most common genetic disorder associated with mental retardation is caused by an expansion of the unstable CGG repeat within the FMR1 gene. Although overgrowth is not the main hallmark of this condition, the fragile X syndrome is usually included in the differential diagnosis of children with mental retardation and excess growth. This review highlights the most recent advances in the field of fragile X research. © 2005 Wiley‐Liss, Inc.
Synthesis and characterization of stearyl‐group‐terminated dendrimers and thermosensitivity of their toluene solutions
Authors: Xu Dong‐Mei , Zhang Ke‐Da , Wu Wen‐Juan
Published: July 2005

Stearyl‐group‐terminated poly(ester amide) dendrimers [PEAD (R)3 and PEAD (R)8] and a poly(amino amide) dendrimer [PAMAM (R)4] were synthesized by the amidation of three, eight, and four terminated primary amino groups in poly(ester amine) dendrimers and a poly(amino amide) dendrimer with stearyl chloride. The dendrimer structures were characterized with IR and elemental analysis. The toluene solutions of the stearyl‐group‐terminated dendrimers were thermosensitive. Not only did gels form in PEAD (R)3–, PEAD (R)8–, and PAMAM (R)4–toluene solutions below 57.5, 60, and 49°C, respectively, but the content of toluene in the gels depended on the temperature, and a break existed at about 30°C. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 341–346, 2005
Cloning and assisted reproductive techniques: Influence on early development and adult phenotype
Authors: Sakai Randall R. , Tamashiro Kellie L. K. , Yamazaki Yukiko , Yanagimachi Ryuzo
Published: July 2005

Over the past 40 years, our increased understanding and development of cell and molecular biology has allowed even greater advances in reproductive biology. This is most evident by the development of various aspects of assisted reproductive techniques (ART), generation of transgenic animals, and most recently generation of mammals through somatic cell cloning. To date, cloning from adult somatic cells has been successful in at least 10 mammalian species. Although generating viable cloned mammals from adult cells is technically feasible and the list of successes will only continue to grow with time, prenatal and perinatal mortality is high and live cloned offspring have not been without health problems. The success of many of the proposed applications of the cloning technique obviously depends upon the health and survival of founder animals generated by nuclear transfer. This article summarizes the health consequences of cloning in mice, and discusses possible mechanisms through which these conditions may arise. In addition, we discuss the effects of ART in animal models and in humans. ART also involves some of the same procedures used in cloning, and there are reports that offspring generated by ART sometimes display aberrant phenotypes as well. It is important to point out that although these techniques do sometimes produce abnormalities, the majority of offspring are born apparently normal and survive to adulthood. Additionally, we must emphasize that the effects of ART and cloning observed in animal models do not necessarily indicate that they will occur in humans. In this article, we review studies examining the phenotype of animals generated by cloning and various ART, and discuss clinical implications of these findings. Birth Defects Research (Part C) 75:151–162, 2005. © 2005 Wiley‐Liss, Inc.
Decision-analytical model with lifetime estimation of costs and health outcomes for one-time screening for abdominal aortic aneurysm in 65-year-old men
Authors: Henriksson M , Lundgren F
Published: July 2005

Background

Abdominal aortic aneurysm (AAA) causes about 2 per cent of all deaths in men over the age of 65 years. A major improvement in operative mortality would have little impact on total mortality, so screening for AAA has been recommended as a solution. The cost-effectiveness of a programme that invited 65-year-old men for ultrasonographic screening was compared with current clinical practice in a decision-analytical model.

Methods

In a probabilistic Markov model, costs and health outcomes of a screening programme and current clinical practice were simulated over a lifetime perspective. To populate the model with the best available evidence, data from published papers, vascular databases and primary research were used.

Results

The results of the base-case analysis showed that the incremental cost per gained life-year for a screening programme compared with current practice was €7760, and that for a quality-adjusted life-year was €9700. The probability of screening being cost-effective was high.

Conclusion

A financially and practically feasible screening programme for AAA, in which men are invited for ultrasonography in the year in which they turn 65, appears to yield positive health outcomes at a reasonable cost.
Mid-term results of endovascular repair of abdominal aortic aneurysm
Authors: Earnshaw J J , Murie J A
Published: July 2005

Vascular specialists may be disappointed
Discretionary unplanned buying in consumer society
Authors: Wood Michael
Published: July 2005

This paper addresses a disjunction between consumer behaviour discourse about ‘impulse buying’ and the reality of shopper behaviour in contemporary marketing and retail environments, by revising the concept of unplanned buying. ‘Discretionary unplanned buying’ is distinguished from impulse buying and is argued to be part of the core meaning of a ‘consumer society’. Consumers buy goods and services with discretionary income intentionally, but without prior planning. It is suggested that such purchases account for a significant portion of the excitement and the ‘hedonic’ satisfaction that consumers receive from their consumption purchases, both in the present day and historically. Consumer experiences as well as the historical development of retail places and consumer society are considered. Copyright © 2005 John Wiley & Sons, Ltd.
Identification and comparative analysis of the peptidyl‐prolyl cis/trans isomerase repertoires of H. sapiens, D. melanogaster, C. elegans, S. cerevisiae and Sz. pombe
Authors: Pemberton Trevor J. , Kay John E.
Published: July 2005

The peptidyl‐prolyl cis/trans isomerase (PPIase) class of proteins comprises three member families that are found throughout nature and are present in all the major compartments of the cell. Their numbers appear to be linked to the number of genes in their respective genomes, although we have found the human repertoire to be smaller than expected due to a reduced cyclophilin repertoire. We show here that whilst the members of the cyclophilin family (which are predominantly found in the nucleus and cytoplasm) and the parvulin family (which are predominantly nuclear) are largely conserved between different repertoires, the FKBPs (which are predominantly found in the cytoplasm and endoplasmic reticulum) are not. It therefore appears that the cyclophilins and parvulins have evolved to perform conserved functions, while the FKBPs have evolved to fill ever‐changing niches within the constantly evolving organisms. Many orthologous subgroups within the different PPIase families appear to have evolved from a distinct common ancestor, whereas others, such as the mitochondrial cyclophilins, appear to have evolved independently of one another. We have also identified a novel parvulin within Drosophila melanogaster that is unique to the fruit fly, indicating a recent evolutionary emergence. Interestingly, the fission yeast repertoire, which contains no unique cyclophilins and parvulins, shares no PPIases solely with the budding yeast but it does share a majority with the higher eukaryotes in this study, unlike the budding yeast. It therefore appears that, in comparison with Schizosaccharomyces pombe, Saccharomyces cerevisiae is a poor representation of the higher eukaryotes for the study of PPIases. Copyright © 2005 John Wiley & Sons, Ltd.
Self‐Assembling Structures of Long‐Chain Sugar‐Based Amphiphiles Influenced by the Introduction of Double Bonds
Authors: Jung Jong Hwa , Do Youngkyu , Lee Young‐A , Shimizu Toshimi
Published: July 2005

Nine phenyl glucoside or galactoside amphiphiles possessing a saturated or unsaturated long alkyl‐chain group as the self‐assembling unit of a highly organized molecular architecture were synthesized. Their self‐assembly properties were investigated by using energy‐filtering TEM (EF‐TEM), SEM, CD, XRD, and FT‐IR techniques. Compound 2, possessing one cis double bond in the lipophilic portion, exhibited twisted helical fibers, which formed a bilayered structure with a 3.59 nm period, while 3 exhibited helical ribbons and left‐handed nanotubular structures with 150–200 nm inner diameters and a wall thickness of approximately 20 nm. Very interestingly, 4, possessing three cis double bonds, exhibited a nanotubular structure with an inner diameter of approximately 70 nm and a d spacing value of 4.62 nm. On the other hand, 7, possessing two trans double bonds in the lipophilic region, exhibited crystal‐ or plate‐like structures, which formed a bilayer structure with a d spacing value of 3.93 nm. These results indicate that the self‐assembly properties are strongly dependent on the type of double bond. Furthermore, 8 and 9, with the galactopyranose moiety, revealed helical ribbon and well‐defined double helical fiber structures, respectively. These findings support the view that the orientation of the intermolecular hydrogen‐bonding interaction between the sugar moieties plays a critical role in producing the nanotubular structures. According to CD and powder XRD experiments, the relatively strong intermolecular hydrogen‐bonding interaction of the glucopyranoside moiety in 3 and 4 provided a highly ordered chiral packing structure. Even though these compounds formed a weak hydrophobic interaction between lipophilic groups, it led to the formation of the nanotubular structure.
Structural Diversity of α‐Amino Acid Based Layer‐Block Dendrons and Their Layer‐Block Sequence‐Dependent Gelation Properties
Authors: Chow Hak‐Fun , Zhang Jie
Published: July 2005

A library of G1–G3 α‐amino acid based layer‐block dendrons 1–6 containing different amino acid residues in the different concentric layers was prepared by solution‐phase peptide synthesis. The structures of these dendrons were characterized by 1H and 13C NMR spectroscopy and, except for the G3 series of compounds, by mass spectrometry. The purities of these compounds were also determined by size‐exclusion chromatography. Owing to the presence of a large number of amide groups, these dendrons exhibit unusually strong self‐aggregating properties in both polar and nonpolar solvents. Some of these dendrons are found to be extremely good organogelators towards aromatic solvents with minimum gel concentrations approaching 4 mg mL−1. Their gelation ability is found to be highly dependent on the nature of the amino acid compositions, the amino acid layer‐block sequence within the dendritic architecture and the nature of the focal‐point functionality. IR spectroscopic analysis indicates that gelation is induced by intermolecular hydrogen bonds. Circular dichroism studies suggest the formation of hierarchical chiral structures in the gel state, although the existence of chiral morphologies could not be observed by scanning electron microscopy.
Highly Stable Neutral and Positively Charged Dicarbollide Sandwich Complexes
Authors: Núñez Rosario , Tutusaus Oscar , Teixidor Francesc , Viñas Clara , Sillanpää Reijo , Kivekäs Raikko
Published: July 2005

Novel sandwich metallacarboranes commo‐[3,3′‐Ni(8‐SMe2‐1,2‐C2B9H10)2] (1), commo‐[3,3′‐Co(8‐SMe2‐1,2‐C2B9H10)2]+ (2+), commo‐[3,3′‐Ru(8‐SMe2‐1,2‐C2B9H10)2] (4) and commo‐[3,3′‐Fe(8‐SMe2‐1,2‐C2B9H10)2] (5) have been prepared by reaction of [10‐SMe2‐7,8‐nido‐C2B9H10]− with NiCl2⋅6 H2O, CoCl2, [RuCl2(dmso)4] and [FeCl2(dppe)], respectively. Reduction of 2+ with metallic Zn leads to the neutral and isolable complex commo‐[3,3′‐Co(8‐SMe2‐1,2‐C2B9H10)2] (3). Theoretical calculations using the ZINDO/1 semiempirical method show three energy minima for complexes 1–3 and 5 that agree with the presence of three different rotamers in solution at low temperature, while four relative energy minima have been found for 4. The calculated rotational energy barriers for complexes 1–5 have been found in the range 5.2±0.2 and 11.5±0.2 kcal mol−1. These values are in agreement with the experimental data calculated for complexes 2+ and 5. Only one rotamer is found in the X‐ray crystal structure of complexes 1–3, while two are observed for 4. Neutral complexes 1, 3 and 4 exhibit a gauche conformation, whereas a cisoid conformation is found for the 2+ ion. Rotamers evident from X‐ray diffraction studies are in agreement with the global energy minimum calculated by the ZINDO/1 method. The electrochemical studies conducted on 1, 3, 4 and 5 support the proposal that the charge‐compensated ligand [10‐SMe2‐7,8‐nido‐C2B9H10]− stabilises lower oxidation states in metals than the dianionic [7,8‐nido‐C2B9H11]2− and even the [C5H5]− ligands.
Using navigators to improve care of underserved patients
Authors: Dohan Daniel , Schrag Deborah
Published: July 2005

BACKGROUND

Logistic, cultural, educational, and other barriers can impede the delivery of high‐quality cancer care to underserved patients. Patient navigation services represent one innovation for addressing perceived barriers to care encountered by disadvantaged patients. In this report, the authors have 1) defined patient navigation, distinguishing it from other cancer support services; 2) described how programs are organized; and 3) discussed the need for research on program effectiveness.

METHODS

Information was examined on navigation programs published in the scientific literature and on line. Qualitative research also was conducted, consisting of direct observation of patient care in cancer clinics with and without navigators in northern California, in‐person interviews with personnel and patients in the clinics observed, and telephone interviews with navigators at four sites across the United States.

RESULTS

The authors found that navigation services have been implemented at all stages of cancer care: prevention, screening, treatment, and survival. Navigators differ from other cancer support personnel in their orientation toward flexible problem solving to overcome perceived barriers to care rather than the provision of a predefined set of services. There are no rigorous demonstrations of the effects and effectiveness of navigation, although such studies are underway.

CONCLUSIONS

Currently, patient navigation is understudied, and literature documenting its effects and effectiveness is scant. Rigorous studies are needed of the navigator role and program costs and benefits. Such studies will facilitate an assessment of program effectiveness, feasibility across a range of health care settings, and performance relative to alternative approaches for addressing barriers to care among the underserved. Cancer 2005. © 2005 American Cancer Society.
Numerical study of mixed freeway traffic flows
Authors: Xie Zhimin , Zhu Zuojin , Hu JunJian
Published: July 2005

This study presents some features in the numerical modelling of multi‐class mixed freeway traffic described by extended LWR model. The evaluation of the eigenvalues and the right characteristic matrix of the mixed traffic system was reported in detail. To some extent, this is the key step in the application of the second‐order symmetrical total variation diminishing (TVD) numerical method to traffic modelling. Examples for four‐class mixed traffic flows were given to illustrate the solution feasibility. It was found that, when the global density wave keeps the same form, the variation of vehicular composition in the initial density wave has no effect on the mean speed of propagation of traffic wave on freeways, but can affect the decay rate of the density wave in different way. Traffic mixing and the impedance of the slow moving vehicles are reasons of the small amplitude density oscillations downstream the main global density wave. Copyright © 2005 John Wiley & Sons, Ltd.