bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prefrontal Serotonin Depletion Affects Reversal Learning But Not Attentional Set Shifting
Authors: Clarke H. F. , Walker S. C. , Crofts H. S. , Dalley J. W. , Robbins T. W. , Roberts A. C. 
Published: January 2005

Recently, we have shown that serotonin (5-HT) depletion from the prefrontal cortex (PFC) of the marmoset monkey impairs performance on a serial discrimination reversal (SDR) task, resulting in perseverative responding to the previously correct stimulus (Clarke et al., 2004). This pattern of impairment is just one example of inflexible responding seen after damage to the PFC, with performance on the SDR task being dependent on the integrity of the orbitofrontal cortex. However, the contribution of 5-HT to other forms of flexible responding, such as attentional set shifting, an ability dependent on lateral PFC (Dias et al., 1996a), is unknown. The present study addresses this issue by examining the effects of 5,7-dihydroxytryptamine-induced PFC 5-HT depletions on the ability to shift attention between two perceptual dimensions of a compound visual stimulus (extradimensional shift).Monkeys with selective PFC 5-HT lesions, despite being impaired in their ability to reverse a stimulus-reward association, were unimpaired in their ability to make an extradimensional shift when compared with sham-operated controls. These findings suggest that 5-HT is critical for flexible responding at the level of changing stimulus-reward contingencies but is not essential for the higher-order shifting of attentional set. Thus, psychological functions dependent on different loci within the PFC are differentially sensitive to serotonergic modulation, a finding of relevance to our understanding of cognitive inflexibility apparent in disorders such as obsessive-compulsive disorder and schizophrenia.
Interactive Effects of Environmental Variability and Military Training on Stream Biota of Three Headwater Drainages in Western Louisiana
Authors: Williams Lance R. , Bonner Timothy H. , Hudson James D. , Williams Marsha G. , Leavy Tracy R. , Williams Casey S. 
Published: January 2005

AbstractWe collected fishes and macroinvertebrates seasonally from eight headwater streams in three different drainage basins (the Red, Calcasieu, and Sabine rivers) crossing Peason Ridge Training Area in west‐central Louisiana. Peason Ridge is part of the Fort Polk military training facility. We used multivariate analyses to test the effects of physical variables (i.e., current velocity, depth, and substrate), time (seasonal variability), drainage basin, and military training activities on assemblage structure. Tributaries of the Red River had the highest gradient and were predominated by shallow, swift‐flowing runs with sandy substrates. Southern tributaries of the Calcasieu and Sabine rivers were of lower stream gradient and contained deep, sluggish runs and pools with large amounts of woody debris and silt. Fish assemblages were structured primarily by military training and drainage basin. Faunal differences among drainage basins probably reflect differences in stream gradient. Fish assemblages in tributaries of the Sabine River were less diverse and showed evidence of historical degradation. Macroinvertebrate assemblages also were structured primarily by military training but had a strong seasonal component related to their short life cycles and high seasonal turnover. In contrast to fishes, macroinvertebrate assemblages were similar among drainages. Because military training was most intense in the Red River basin, its significance in these models probably represents differences in stream gradient among the basins because we found no negative effect on stream biota resulting from current training activities. Rather, historical logging and the resultant siltation coupled with isolation of populations by reservoirs are probable explanations for the changes in fish assemblages in tributaries of the Sabine River.
Age‐0 Black Crappie Abundance and Size in Relation to Zooplankton Density, Stock Abundance, and Water Clarity in Three Florida Lakes
Authors: Dockendorf Kevin J. , Allen Micheal S. 
Published: January 2005

AbstractCrappies Pomoxis spp. are popular sport fishes but are often difficult to manage due to highly variable recruitment. To assess the factors influencing recruitment, we investigated the size and abundance of age‐0 black crappie P. nigromaculatus in relation to zooplankton density, adult stock abundance, and water clarity in three productive Florida lakes. Age‐0 black crappies were collected at Lakes Wauberg, Lochloosa, and Tarpon by use of surface and bottom trawls during the spring, summer, and fall of 2000 and 2001. Zooplankton abundance was measured concurrently with trawl sampling. Early‐summer juvenile abundance was positively related to stock abundance during the previous fall among lakes, indicating a relationship between stock size and juvenile black crappie abundance. Early‐summer juvenile abundance was positively related to juvenile abundance in the fall (i.e., at the end of the first summer), suggesting that year‐class strength was set by early summer in all lakes. Lake Lochloosa had the highest crustacean zooplankton abundance in both years, but this lake had the smallest age‐0 black crappie size and intermediate age‐0 fish abundance. Thus, we found no relationship between crustacean zooplankton density and black crappie size across lakes. Reduced Secchi depths due to high chlorophyll‐a values and wind resuspension of sediments may have reduced feeding efficiency for age‐0 black crappies at Lake Lochloosa relative to the other lakes. Age‐0 black crappie abundance and size during fall were not predicted solely by food availability, stock abundance, or water clarity, suggesting that these factors interacted to influence recruitment through the first year of life.
Development of a Morphological Index of the Nutritional Status of Juvenile Largemouth Bass
Authors: Smith Chris D. , Higgins Christopher L. , Wilde Gene R. , Strauss Richard E. 
Published: January 2005

AbstractWe describe the morphological changes associated with starvation in larval largemouth bass Micropterus salmoides and develop bivariate and multivariate morphological indices of nutritional status. We obtained hatchery‐reared largemouth bass, raised them until completion of fin development, and divided them into two randomized experimental groups of fed and unfed fishes. Fed fishes were provided with newly hatched brine shrimp twice daily. We quantified morphological changes in body shape using 23 morphometric characters. After only 3 d of food deprivation, we were able to detect statistically significant differences in morphology between the fed and unfed fish using multivariate analysis. The magnitude of the mean difference increased over time. An unexpected result suggested that a simple, bivariate ratio of standard length to body depth at the anus was almost as efficient and robust at classifying fed and unfed largemouth bass from an independent data set as a multivariate index based on all 23 morphometric characters. The relative ease of use, combined with a small level of misclassification error rate and a firm foundation in whole‐body changes, makes these ratio indices effective tools for detecting food deprivation in larval largemouth bass.
Competition between Hatchery‐Reared and Wild Juvenile Chinook Salmon in Enclosures in the Sacramento River, California
Authors: Weber Edward D. , Fausch Kurt D. 
Published: January 2005

AbstractWe conducted two types of experiments in the upper Sacramento River, California, to test the effects of hatchery‐reared juvenile Chinook salmonOncorhynchus tshawytschaon the emigration, growth, and survival of their wild counterparts. In 3 years of displacement experiments, emigration rates from 8‐m2enclosures into downstream traps were similar between control enclosures that contained 40 wild fish and treatment enclosures to which 33 or 40 hatchery fish were also added. The mean number of wild fish in enclosures at the end of experiments differed by less than one fish between treatments and controls during all 3 years, indicating that hatchery fish prompted few wild fish to emigrate. In 2 years of competition experiments wherein fish could not emigrate, the enclosures contained wild fish (40 fish), wild fish plus hatchery fish (40 wild fish plus 33 or 40 hatchery fish), or wild fish at the same total density as the treatment with wild plus hatchery fish (73 or 80 wild fish). During 2001, survival and specific growth rates of wild fish were similar among treatments, probably because resources were not limiting. During 2002, survival was similar among treatments, but the mean specific growth rate was 0.008 g/d higher in the treatment with 40 wild fish than in the treatment with wild plus hatchery fish (95% confidence interval (CI), 0.005–0.011 g/d). These data indicated a negative effect on wild fish growth of adding hatchery fish. The specific growth rate in the high‐density wild fish treatment was intermediate and 0.003 g/d higher than in the treatment with hatchery fish (95% CI, −0.0005 to +0.006 g/d), providing some evidence that hatchery fish had a greater negative effect on wild fish growth than an equal density of wild fish did.
Effects of Temperature on Survival and Development of Early Life Stage Pacific and Western Brook Lampreys
Authors: Meeuwig Michael H. , Bayer Jennifer M. , Seelye James G. 
Published: January 2005

AbstractWe examined the effects of temperature (10, 14, 18, and 22°C) on survival and development of Pacific lampreys Lampetra tridentata and western brook lampreys L. richardsoni during embryological and early larval stages. The temperature for zero development was estimated for each species, and the response to temperature was measured as the proportion of individuals surviving to hatch, surviving to the larval stage, and exhibiting abnormalities at the larval stage (i.e., malformations of the body). The estimated temperature for zero development was 4.85°C for Pacific lampreys and 4.97°C for western brook lampreys. Survival was greatest at 18°C, followed by 14, 10, and 22°C, significant differences being observed between 22°C and the other temperatures. Overall survival was significantly greater for western brook lampreys than for Pacific lampreys; however, the overall difference in proportion of individuals surviving was only 0.02. Overall survival significantly decreased from the time of hatch (proportion surviving = 0.85) to the larval stage (0.82; i.e., during the free‐embryo stage). The proportion of individuals exhibiting abnormalities at the larval stage was greatest at 22°C, followed by 18, 10, and 14°C, significant differences being observed between 22°C and the other temperatures. These data provide baseline information on the thermal requirements of early life stage Pacific and western brook lampreys and will aid in assessment and prediction of suitable spawning and rearing habitats for these species.
A Laboratory Evaluation of Poststocking Predatory Losses for Cultured Largemouth Bass
Authors: Schlechte J. Warren , Betsill Robert K. , Buckmeier David L. 
Published: January 2005

AbstractStocking fish into preexisting fish communities is not always successful. Although there may be many reasons why stockings fail, predation is perhaps the most likely reason. Reducing predation by allowing fish to become accustomed to their new environment before release (i.e., habituation) may improve stocking efficiency. We evaluated the effect of habituation on predation of stocked, hatchery‐reared fingerling Florida largemouth bass Micropterus salmoides floridanus (30–64 mm total length) in simple (i.e., open‐water) and structurally complex (i.e., with vegetation and cobble) habitats in indoor tanks. We found that fingerling largemouth bass survival significantly increased (P < 0.004) from 26% to 46% when fish were habituated in a predator‐free enclosure for at least 15 min. Surviving fish spent most (95%) of their time in the structurally complex habitat. However, the survival of all fish stocked in structurally complex habitat did not differ from that of all fish stocked in open water (P = 0.61). Although predation on nonhabituated, hatchery‐reared largemouth bass approached 75%, we found that short‐term habituation can enhance survival of stocked largemouth bass, as manifested by improved predator avoidance. This suggests that habituating fingerling largemouth bass before stocking may result in substantial increases in survival.
Age‐0 Gizzard Shad Abundance is Reduced in the Presence of Macrophytes: Implications for Interactions with Bluegills
Authors: Michaletz Paul H. , Bonneau Joseph L. 
Published: January 2005

AbstractThe abundance of gizzard shad Dorosoma cepedianum may be reduced in the presence of macrophytes, which may lessen the frequently observed negative interactions with coinhabiting bluegills Lepomis macrochirus. We used a series of experimental pond studies and a small‐lake data set to examine relationships among gizzard shad, bluegills, and macrophytes. Fall age‐0 gizzard shad abundance was lower in vegetated experimental ponds than in unvegetated ponds, but mean total length (TL) did not differ. Larval gizzard shad abundance did not differ between vegetated and unvegetated ponds, but the relative survival of age‐0 gizzard shad (ratio of fall juveniles to the total number of larvae collected) was higher in unvegetated ponds. In ponds with macrophyte coverage ranging from 0% to 100%, age‐0 gizzard shad abundance declined with increasing macrophyte coverage; however, age‐0 bluegill abundance was unrelated to macrophyte coverage. The abundance and size of age‐0 gizzard shad and age‐0 bluegills were unrelated in these ponds. By examining the small‐lake data, we found that the proportion of lakes containing gizzard shad decreased with increasing macrophyte coverage. The proportion of bluegill populations containing large adults (>203 mm TL) increased with macrophyte coverage for lakes with gizzard shad but not for lakes without gizzard shad. Although the actual mechanisms are not clear, we suggest that competitive interactions between gizzard shad and adult bluegills are density dependent and lessen with increasing macrophyte coverage because of decreasing gizzard shad abundance.
A Nonlethal, Rapid Method for Assessing the Somatic Energy Content of Migrating Adult Pacific Salmon
Authors: Crossin Glenn T. , Hinch Scott G. 
Published: January 2005

AbstractTraditional methods for determining the energy content of fish involve either chemical assays of lipid and protein levels (proximate analyses) or tissue combustion (bomb calorimetry). In studies of migrating Pacific salmon Oncorhynchus spp., entire fish need to be homogenized prior to analysis, as energy reserves are stored along a head‐to‐tail gradient and change along this gradient depending on the stage of upriver migration. The logistics and costs associated with transporting carcasses to the laboratory can be prohibitive. Also, many populations of Pacific salmon are at risk of extinction, so lethal sampling is often not an option. Few reliable and practical methods exist that enable rapid and nonlethal energy determinations of large fish in the field. We evaluated a handheld microwave energy meter as a means of estimating whole‐body energy concentrations. In 2002 and 2003, we collected sockeye salmon O. nerka from several stocks during their coastal and upriver migration through the Fraser River watershed (British Columbia). For each stock, we sampled fish from various locales ranging from ocean to spawning areas. Fish somatic tissues were interrogated at four body positions; however, the two most anterior positions produced the most accurate energy information. It took less than 30 s per fish to collect these data. We found strong regression relationships between somatic lipid percentage (R2 = 0.93; P < 0.001) and gross somatic energy density (R2 = 0.94; P < 0.001) measured by whole‐carcass proximate analyses and loge transformed energy meter readings. The slopes and intercepts of these relationships did not differ among stocks or years.
Experimental study of feasibility in kinetically‐controlled reactive distillation
Authors: Chiplunkar Madhura , Hong Mooho , Malone Michael F. , Doherty Michael F. 
Published: January 2005

AbstractBifurcation studies predict limited ranges of feasibility for products in certain reactive distillations. These are closely related to the bifurcations in the singular points of dynamic models for simple reactive distillation (isobaric open evaporation with liquid phase reaction). A new dynamic model is described with constant vapor rate together with an experimental study for the reactive distillation of acetic acid with isopropanol to produce isopropyl acetate, catalyzed by Amberlyst‐15 ion‐exchange resin. An experimental apparatus with real‐time measurement of liquid compositions based on Fourier transform infrared (FTIR) spectroscopy is described, and used to follow the composition dynamics at several initial conditions and Damköhler numbers (Da). The experimental results match model predictions that show four regions of behavior. For Da ≈ 1, these show a stable node at acetic acid and several other fixed points as saddles. However, near Da ≈ 2, both isopropanol and acetic acid are stable nodes and a quaternary singular point appears. The presence of two stable nodes requires the presence of a distillation boundary and, therefore, a limited feasibility for the bottom product compositions from continuous reactive distillation. For the reaction rates studied, the model predictions are closely consistent with the experimental findings, and are robust to variations in the vapor rate. These experiments are among the first to analyze the dynamics and feasibility in a kinetically‐controlled reactive distillation and are consistent with previous studies for the reaction equilibrium limit, indicating the formation of a reactive azeotrope. © 2005 American Institute of Chemical Engineers AIChE J, 51: 464–479, 2005
Resistivity and thermal reproducibility of carbon black and metallic powder filled silicone rubber heaters
Authors: Park Eun‐Soo , Wook Jang Lee , Yoon Jin‐San 
Published: January 2005

AbstractFlexible heaters were prepared by extruding platinum‐catalyzed silicone rubber composites with conductive carbon black (CB) and metallic fillers. The conductor resistivity of the extruded heaters decreased in order of conductive titanium dioxide (TiO2) > aluminum powder ≈ zinc powder > copper powder. Thermoelectric switching phenomena were investigated for the silicone rubber/CB/metallic powder systems. The positive temperature coefficient effect was dependent mainly on the CB content rather than on the content of the metallic powders. Resistivity and thermal reproducibility of the extruded heaters were also investigated by periodically applying AC voltage of 110 V. The heaters containing copper and TiO2 powders exhibited excellent electrical reproducibility. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 95: 1122–1128, 2005
Conformational investigations on analogs of inflammation response inducing chemotactic tripeptide fMLP
Authors: Rathore Ravindranath Singh 
Published: January 2005

AbstractConformations of three analogs of for–L‐Met–L‐Leu–L‐Phe–OH (fMLP), which initiates inflammatory response by interaction with the formyl peptide receptor (FPR), have been investigated by the application of the X‐ray crystallographic technique. The investigated analogs of fMLP peptides are as follows: for–L‐Met‐1–amino‐1–cyclooctane–carbonyl(Ac8c)–L‐Phe–OMe (1); for–L‐Met–L‐Leu–L‐p‐iodo‐Phe–OH (2); and for–L‐Met–di‐n‐propylglycyl(Dpg)–L‐Phe–OMe (3). The peptide backbone in 1 and 3 is constrained at position 2 of fMLP by the introduction of Cα,α‐disubstituted glycines. In peptide 2, Phe–OMe is substituted by p‐iodo‐Phe–OH. Crystal structures reveal an overall folded conformation adopted by 1 and 2. The former is folded in the type II β‐turn, which is stabilized by an intramolecular 1 ← 4 (formyl) CO · · · HN (Phe) hydrogen bond, whereas the latter is folded in an open turn without any intramolecular hydrogen bond. On the other hand, peptide 3 has an extended conformation, and two different molecules (3a, 3b) in a crystallographic asymmetric unit form an antiparallel β‐sheet‐like structure. In 1 and 3, residues Ac8c and Dpg adopt left‐handed helical and fully extended (C5) conformations, respectively. The cyclooctane ring in Ac8c acquires a boat‐chair conformation. Crystal packing of 1 is characterized by the association of aliphatic‐aromatic rings via a CH · · · π interaction. In the crystal of 2, contrary to the usual observations, peptides are interlinked via networks of head‐to‐tail hydrogen bond and π · · · π interactions, which are generally observed to be mutually exclusive. The structure–function mechanism of the ligand–receptor interaction is discussed. © 2005 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 80: 651–664, 2005This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Incidence and follow‐up of patients with focal prostate carcinoma in 2 screening rounds after an interval of 4 years
Authors: Postma Rensbe , de Vries Shijn H. , Roobol Monique J. , Wildhagen Mark F. , Schröder Fritz H. , van der Kwast Theo H. 
Published: January 2005

AbstractBACKGROUNDFocal carcinoma detected by needle biopsy has been a common finding since prostate‐specific antigen (PSA)‐based screening was introduced. Clinicopathologic features in patients with focal prostate carcinoma who underwent radical prostatectomy (RP) or who were treated with watchful waiting (WW) were analyzed to detect clinical predictors for disease progression during follow‐up.METHODSPatients were selected from the European Randomized Screening study for Prostate Cancer. Focal carcinoma on sextant biopsy was defined as ≤ 3.0 mm involvement by tumor in 1 biopsy core lacking Gleason pattern 4 or 5. PSA doubling time was used in the WW group as a marker of disease progression.RESULTSThe proportion of patients with focal prostate carcinoma increased significantly from 16% in the first screening round to 29% in the second screening round. One hundred eighteen men underwent RP, and 108 men were treated with WW. The median tumor volume was 0.13 mL. PSA level and prostate volume were predictive for tumor volume in a multivariate regression analysis. A PSA density cut‐off level of ≤ 0.1 ng/mL/cm3 predicted organ‐confined tumor (< 0.5 mL) in 94% of patients. Positive surgical margins were predictive for PSA recurrence. Four patients in the RP group had PSA recurrence at follow‐up. PSA doubling times < 2 years, < 3 years, and < 4 years were noted in 4.9%, 14.6%, and 22.0% of patients in the WW group, respectively.CONCLUSIONSThe median tumor volume was small (0.13 mL). A comparison between PSA recurrence in the RP group and PSA doubling time in the WW group showed a significantly more favorable outcome after RP if a PSA doubling time of < 3 years or < 4 years was chosen as a marker for disease progression in the WW group. A WW policy with delayed curative intent may be recommended in patients ages 55–75 years with focal carcinoma and PSA density < 0.1 ng/mL/cm3. Cancer 2005. © 2005 American Cancer Society.