bluuebunny/crossref_metadata_2025 huggingface dataset:
Relative Bioavailability of Fentanyl Following Various Dosing Regimens of Fentanyl Buccal Tablet in Healthy Japanese Volunteers
Authors: Darwish Mona , Tempero Kenneth , Jiang John G. , Simonson Philip G.
Published: June 2008

Background.  Fentanyl buccal tablet (FBT; FENTORA®, Cephalon, Inc., Frazer, PA, USA) is indicated in the US for breakthrough pain in patients with cancer who are already receiving and are tolerant to around‐the‐clock opioid therapy for underlying persistent cancer pain. For each individual patient, FBT should be titrated to the effective dose.

Objective.  The primary objective was to characterize the pharmacokinetic parameters of FBT 400 µg administered as a single 400 µg tablet (regimen A) or as two 200 µg tablets given simultaneously (regimen B) and determine whether these are bioequivalent in healthy Japanese volunteers. Regimen C (two 200 µg tablets 30 minutes apart) was also compared as a secondary objective.

Methods.  Healthy Japanese adults received regimens A, B, and C in a crossover fashion. Naltrexone was given to minimize the opioid effects of fentanyl. Serum fentanyl concentrations were determined in venous blood collected through 36 hours post dose. Regimens were declared bioequivalent with respect to bioavailability (as reflected by AUC0–∞, AUC0–last, and Cmax) if the 90% confidence interval (CI) of the regimens' ratio fell within 0.80–1.25 (80%–125%).

Results.  Twenty‐nine volunteers (13 men, 16 women) were enrolled; 24 completed the study. Regimens A and B had bioequivalent systemic exposure parameters (B/A [90% CI]: AUC0–∞108.4 [103.4, 113.7], AUC0–last 106.1 [100.7, 111.7], and Cmax 92.3 [83.2, 102.4]). Regimen C was bioequivalent to both A and B for AUCs, but only to B for Cmax. Median time to Cmax was 45 minutes for regimen A and 60 minutes for regimens B and C. The most frequent AEs were dizziness, application‐site erythema, headache, somnolence, nausea, and vomiting. All AEs were mild or moderate.

Conclusions.  Bioavailability of fentanyl after FBT 400 µg administered as a single tablet was bioequivalent to that after 2 simultaneously administered 200 µg tablets in healthy Japanese volunteers. AEs were mild or moderate.
JNK supports survival in melanoma cells by controlling cell cycle arrest and apoptosis
Authors: Alexaki Vasileia‐Ismini , Javelaud Delphine , Mauviel Alain
Published: June 2008

JNK1/2 proteins belong to the family of stress‐activated protein kinases. They play a complex role in growth regulation, inducing either cell death or growth support. In this report, we provide evidence that, in human melanoma cells, JNK inhibition with the small molecule inhibitor SP600125 induces either predominantly a G2/M arrest or apoptosis depending on the cell line. In 1205Lu cells, JNK inhibition induced cell cycle arrest through p53‐dependent induction of p21Cip1/Waf1 expression, while in WM983B cells, induction of apoptosis by JNK inhibition was accompanied by p53, Bad and Bax induction, not p21Cip1/Waf1. JNK inhibition with the small molecule inhibitor SP600125 slowed growth of all cell lines, although the effect was markedly greater in cells exhibiting high phospho‐ (P‐)JNK1 levels. Specific gene knockdown of JNK1 by means of siRNA oligonucleotides inhibited cell growth only in melanoma cell lines exhibiting high P‐JNK1 levels. siRNAs directed against JNK2 did not reduce cell growth in any of the cell lines tested. Together, our findings demonstrate that JNK, and in particular the JNK1 isoform, support the growth of melanoma cells, by controlling either cell cycle progression or apoptosis depending on the cellular context.
The location of heart melanocytes is specified and the level of pigmentation in the heart may correlate with coat color
Authors: Yajima Ichiro , Larue Lionel
Published: June 2008

Melanocytes are mainly found in the skin and more rarely in other parts of the body, including the heart. We analyzed the localization of heart melanocytes and their levels of pigmentation in a series of mutant mice presenting different numbers of melanocytes and pigmentation in the skin. We found that melanocytes were localized in the valves (mitral, tricuspid, and aortic) and septa (ventricular and atrial). Moreover, the numbers of melanocytes in the heart appears to reflect that of the skin. Mice having a high or low level of pigmented cells and/or melanin in valves and septa have similar lifespan. In this respect, melanocytes found in the valves and septa of the heart are probably not essential in a healthy and non‐stressful environment.
Rapamycin prevents mesenteric neo‐angiogenesis and reduces splanchnic blood flow in portal hypertensive mice
Authors: Geerts Anja M. , Vanheule Eline , Van Vlierberghe Hans , Leybaert Luc , Van Steenkiste Christophe , De Vos Martine , Colle Isabelle
Published: June 2008

Aim:  Increased angiogenesis in the mesenteric microvasculature of portal hypertensive animals may contribute to the development of splanchnic vasodilation associated with portal hypertension (PHT). Experimental data suggest that rapamycin may reduce angiogenesis and tumour growth by inhibiting the vascular endothelial growth factor (VEGF) pathway. This study determines whether rapamycin can prevent the neoangiogenesis in the mesentery of portal hypertensive mice and may influence the splanchnic vasodilation.

Methods:  PHT was induced by partial portal vein ligation (PPVL). PPVL and Sham mice were treated daily with rapamycin or placebo for 2 weeks. Protein expressions of VEGF, CD 31, Akt and p70S6 kinase (mTOR signalling pathway) were evaluated. Mesenteric blood flow (MBF) was measured by a perivascular flow probe.

Results:  Increased mesenteric angiogenesis and VEGF protein levels were observed in PPVLplacebo mice compared to Shamplacebo mice. Rapamycin treatment caused significant reduction in CD 31 positive endothelial cells and VEGF protein in the PPVLrapamycine group compared to the PPVLplacebo group, to levels comparable with Shamplacebo and Shamrapamycine groups. MBF was significantly higher in PPVLplacebo mice compared to the Shamplacebo mice. Rapamycin decreased significantly the MBF in PPVLrapamycine mice compared to PPVLplacebo mice. Phospo‐Akt and p70S6 kinase protein levels were increased in the mesenteric tissue of PPVLplacebo mice compared to Shamplacebo mice, which were also prevented by treatment with rapamycin.

Conclusions:  An increased VEGF dependent neo‐angiogenesis is present in the mesentery of portal hypertensive mice. Rapamycin prevents angiogenesis in the mesenteric tissue and decreases the mesenteric blood flow in portal hypertensive mice, at least in part through an anti‐VEGF activity and influence on the mTOR signalling pathway.
Association between changes in body composition and the increasing prevalence of fatty liver in Japanese men
Authors: Imamura Yasushi , Uto Hirofumi , Oketani Makoto , Hiramine Yasunari , Hosoyamada Kaori , Sho Yukihiko , Hiwaki Takuya , Baba Yoshirou , Tahara Kenji , Kubozono Osamu , Kusano Ken , Tsubouchi Hirohito
Published: June 2008

Aim:  Prevalence of fatty liver is increasing. In this study, to elucidate the factor that contributes most to recent increases in prevalence of fatty liver, we determined the independent predictors for the onset of fatty liver and compared these predictors between 2000 and 2005.

Methods:  Japanese persons, aged 30–74 years, who participated in regular health checks at Kagoshima Kouseiren Medical Health Care Center (10 336 persons in 2000 and 11 011 persons in 2005) were enrolled in the study. Diagnosis of fatty liver was performed by ultrasonography. Body fat percentage (BFP) was determined using a bipedal bioimpedance instrument.

Results:  The prevalence of fatty liver has increased between 2000 and 2005 in men (33.3 vs 38.5% in 2000 vs 2005, respectively, P < 0.0001), but not in women (21.3 vs 21.0%, P = 0.8101). Logistic regression analysis revealed that both body mass index (BMI) and BFP are independent predictors of fatty liver in both men and women. BMI did not change in either men (23.4 ± 2.9 vs 23.8 ± 3.0 kg/m2, P = 0.0528) or women (22.8 ± 3.1 vs 22.8 ± 3.3 kg/m2, P = 0.9862) during the survey period. In contrast, BFP increased in men (20.6 ± 4.7 vs 22.3 ± 5.0 kg/m2, P = 0.0003), but not in women (27.4 ± 5.5 vs 28.4 ± 5.9 kg/m2, P = 0.3993). There was no significant change in triglycerides and glucose levels.

Conclusion:  These results suggest that altered body composition, particularly increased BFP without an increase in BMI, has developed in men and is strongly associated with the increasing prevalence of fatty live amongst Japanese men.
Cooling strategies improve intermittent sprint performance in the heat of athletes with tetraplegia
Authors: Webborn N , Price M J , Castle P , Goosey-Tolfrey V L
Published: June 2008

Background

Precooling has been shown to enhance performance in repeated sprint exercise in able-bodied subjects in a hot environment. Spinal cord injury causes thermoregulatory impairment with a detrimental effect on performance. This study assessed whether cooling strategies before and during exercise in the heat enhances sprint performance in athletes with tetraplegia.

Methods

Eight male athletes with tetraplegia performed intermittent arm crank exercise in the heat (32.0°C (0.1°C); humidity, 50% (0.1%)) for a maximum of 60 min or until exhaustion. Trials involved a no-cooling control (CON), precooling (PRE) or cooling during exercise (DUR). Each intermittent sprint protocol consisted of varied periods of passive rest, maximal sprinting and active recovery.

Results

Both PRE and DUR cooling strategies improved the ability of the athletes to repeatedly perform high-intensity sprints, with times to exhaustion (TTE), whereas during the CON trial, athletes demonstrated a reduction in the total number of sprints and TTE (47.2 (10.8), 52.8 (5.8) and 36.2 (9.6) min for CON, PRE and DUR, respectively). Core temperature was significantly higher for CON (37.3°C (0.3°C)) when compared with both PRE and DUR (36.5°C (0.6°C) and 37.0°C (0.5°C), respectively, p<0.01). Ratings of perceived exertion and thermal sensation upon exhaustion or completion were not different.

Conclusions

Athletes with tetraplegia should use a precooling or during-exercise cooling strategy specific to the characteristics of their sport when exercising in hot conditions.
Does exercise training during pregnancy affect gestational age? A randomised controlled trial
Authors: Barakat R , Stirling J R , Lucia A
Published: June 2008

Background:

Some controversy exists over the possibility that exercise during pregnancy might increase the risk of preterm delivery.

Objective:

This study aimed to determine the possiblecause–effectrelationship between regular exercise performed during the second and third trimesters of pregnancy by previously sedentary, healthy gravidae and gestational age at the moment of delivery.

Methods:

Caucasian (Spanish) women with singleton gestation were assigned to either a training (n = 72) or a control (n = 70) group. The supervised training programme focused mainly onverylight resistance and toning exercises and included ∼80 sessions (three times/week, 35 min/session from weeks 12–13 to weeks 38–39 of pregnancy).

Results:

No significant differences were found (p>0.05) between the groups in those maternal characteristics (age, smoking habits, number of hours standing or prior parity history) that could potentially influence gestational age. The mean gestational age did not differ (p = 0.745) between the training (39 weeks,3 days (SD 1 day)) and the control group (39 weeks,4 days (SD 1 day)).

Conclusions:

Previously sedentary, healthy gravidae with singleton gestation can safely engage in moderate, supervised exercise programmes until the end of gestation as this would not affect gestational age.
Lagrangian sediment motion in a crescentic nearshore bar under storm-induced waves and currents
Authors: Greenwood Brian , Hale Peter B.
Published: June 2008

A fluorescent tracer experiment, in conjunction with morphological and sedimentological data, demonstrates the Lagrangian sediment flux induced by storm waves and currents in a permanently submerged, outer crescentic nearshore bar system. The steady state bar form (height = 2.6 m, wavelength = 390 m) is maintained in the presence of landward sediment advection under asymmetric oscillatory flow during storm buildup and decay and seaward advection under rip-cell flows at the peak of the storm. The seaward displacement of the bar crest in the areas of the convex seaward crescent reflects transport associated with the rip current, which, though variable in its location through time, is never located over the landward projecting horns. The storm studied had a recurrence interval of approximately 1 month and reworked upwards of 16% of the bar sediments. The sediment flux indentified is therefore associated with an event of frequent occurrence and is most likely the control on both bar form and dynamics of the bar system.
Induced earthquakes at a potash mine near Saskatoon, Canada
Authors: Gendzwill D. J. , Horner R. B. , Hasegawa H. S.
Published: June 2008

Four earthquakes with magnitudes between 2.3 and 3.0, which occurred between November 1979 and August 1980, are correlated with a potash mining operation near Saskatoon. Previous seismicity in the region is unknown. Detailed intensity surveys constrain the epicentres over, or close to, the periphery of the underground mining excavations. From microearthquake recordings over the mine, and from an analysis of short-period surface waves recorded for the March 18 event, focal depths are constrained to the region above the excavation. Microearthquakes show both temporal and spatial correlations with the mining activity. The results indicate that the relatively competent carbonate rock above the mine is spasmodically undergoing brittle failure or sudden rupture (presumably normal faulting) due to induced changes in the local stress–strain regime as a result of the mining excavation and the accompanying subsidence in the mine overburden.
An 18 000 year palynological record from the southern Alberta segment of the classical Wisconsinan "Ice-free Corridor"
Authors: Mott R. J. , Jackson Jr. L. E.
Published: June 2008

Radiocarbon dates of 18 300 ± 380 years BP (GSC-2668) and 18 400 ± 1090 years BP (GSC-2670) on moss fragments from the clay near the base of a core from Chalmers Bog, Alberta indicate that the classical Wisconsinan "Ice-free Corridor" was in existence in the foothills of southern Alberta by this time. Palynological studies show sparse, herbaceous, tundra-like vegetation probably prevailed at this time in the area surrounding the small lake formed in the abandoned glacial spillway. Later, shrubs became more prominent to form a shrub tundra environment. Sometime before 8220 years BP (GSC-2851) trees began to invade the area and the Pinus contorta dominated coniferous forest extant in the area today began to form. Bog and fen vegetation invaded the shallow lake basin about this time as well to form the bog that occupies the basin to the present day.
In situ gasification of coal, a natural example: history, petrology, and mechanics of combustion
Authors: Bustin R. M. , Mathews W. H.
Published: June 2008

A 6 m thick coal seam of the Upper Jurassic and Lower Cretaceous Mist Mountain Formation in the southeastern Canadian Cordillera has been burning since 1936. The upper 3 m of coal is being consumed to an estimated depth of 20 m. Temperatures in excess of 1100 °C are locally reached, resulting in the melting of overlying sandstones and shales. The melted and vitrified rocks contain a new suite of minerals, including diopside, anorthite, cristobalite, and tridymite. Underlying the burnt coal ash is a zone of coke averaging about 10 cm thick, which is in turn underlain by unaltered coal.Within the area of combustion three zones can be distinguished: an advance zone, where open cracks are developed at the ground surface; a zone of active combustion, where volatiles driven off the coal burn en route to the surface and at the mouth of vents; and an abandoned zone marked by vents, some of which act as air intakes. Approximately 1000 t/year of coal is consumed, giving an energy release of about 1 MW. The heat generated is carried both forward and upward by convecting gas, thereby coking the coal and baking the roof rock. Little heat is carried downward, as evident from a sharp decrease in vitrinite reflectance below the zone of combustion.The baked roof rocks are brittle and extensively fractured, providing little roof support. The completely fused and scoriaceous rock and welded associated breccias, on the other hand, have greater coherence. This welding hinders roof collapse and thereby assists the passage of gases.
Observations on the Attawapiskat Formation (Silurian) trilobites of Ontario, with description of a new encrinurine
Authors: Gass Kenneth C. , Mikulic Donald G.
Published: June 2008

The trilobite fauna of the Attawapiskat Formation of Ontario agrees with a late Llandoverian to early Wenlockian age assignment. This fauna is closely related to late Llandoverian and Wenlockian trilobite faunas from eastern Iowa and eastern Greenland. The numerically dominant trilobites of this fauna (illaenids, scutelluids, cheirurids) represent an association that is typical of Ordovician–Devonian carbonate buildups. These trilobites occur in localized accumulations formed by the entrapment of exuviae in depressions or other similar structures.Perryus severnensis gen. et sp. nov. from the Attawapiskat Formation is described. Its relationships with the Encrinuroides/Cromus lineage and possibly with Frammia are discussed.
Laurentide glaciation in west-central Alberta: a single (Late Wisconsinan) event
Authors: Liverman David G. E. , Catto N. R. , Rutter N. W.
Published: June 2008

The Grande Prairie region in west-central Alberta shows evidence of Late Wisconsinan Laurentide glaciation in the form of a widespread till, containing abundant erratic clasts derived from the Canadian Shield. Two sections, located on the Smoky River at Watino and on the Simonette River 80 km to the southwest, expose sediment lying stratigraphically below the till. A similar sequence is exposed in both localities: 5–10 m of coarse quartzite gravel overlain by a thick sequence of sand and silt. The gravel contains no Laurentide erratics and is thus preglacial. The contact between the basal gravel and the overlying sand and silt is sharp and conformable. 14C dates from the base of the Simonette section and throughout the Watino section suggest a Middle Wisconsinan age. Thus, the sediment exposed is interpreted as a conformable Middle Wisconsinan sequence. The sedimentary sequences were deposited in a moderate- to low-energy braided stream system flowing towards the north. The general fining-up trend in the sections was produced as a result of channel abandonment, rather than by a change in regional base level. The sand and gravel units contain no material derived from the Canadian Shield. Consequently, the surface till is Late Wisconsinan, and represents the only Laurentide glaciation in this area of Alberta.
Sedimentology and diagenesis of Upper Mississippian to Lower Permian strata, Talbot Lake area, Jasper National Park, Alberta
Authors: Ng Kwok-Choi , Jones Brian
Published: June 2008

In the Talbot Lake area, the Upper Mississippian carbonate sequence comprises, in ascending order, the Turner Valley and Mount Head formations. The Mount Head Formation is informally divided into lower and upper members. The rocks of the Upper Mississippian originated by sedimentation associated with successive shallowing-upward sequences. On the basis of the fossils, lithologies, textural characters, and sedimentary structures, the Turner Valley Formation apparently resulted from sedimentation on open marine shoals and in a lagoon, the lower member of the Mount Head Formation from sedimentation in shallow subtidal to lower supratidal environments, and the upper member of the Mount Head Formation from deposition in upper intertidal to supratidal environments.The paraconformity between the lower and upper members of the Mount Head Formation records a short erosional break. A disconformity between the Upper Mississippian carbonates and the Upper Permian Ishbel Group displays paleotopographic relief and paleokarstic features developed during exposure in post-Mississippian times. The disconformity is overlain by a condensed sequence of Pennsylvanian to Permian strata.Major diagenetic modifications of the Upper Mississippian strata include dolomitization, silica replacement and cementation, carbonate cementation, and dedolomitization. A diagenetic realm comprising sea water, fresh water, and hypersaline brine was probably responsible for some of the complex diagenesis in these rocks.
Middle Proterozoic (1200–1400 Ma) microfossils from the Western Hills near Beijing, China
Authors: Pengyuan Zhang , Mu Zhu , Wu Song
Published: June 2008

Eleven species of microfossils have been recognized in cherts from shallow-marine and intertidal dolostones of the Wumishan Formation (1200–1400 Ma), in the Western Hills near Beijing. Of these, one is a new taxon: Oscillatoriopsis subtilis n.sp. The microbiota has some affinities with that of the approximately coeval Dismal Lakes assemblage in arctic Canada.
Chronology of Late Wisconsinan glaciation, Emerald Basin, Scotian Shelf
Authors: Gipp Michael R. , Piper David J. W.
Published: June 2008

Eight new accelerator mass spectrometry (AMS) radiocarbon dates from proglacial sediments in Emerald Basin indicate that the previously proposed chronology, based on dates of total organic matter, is much too old. The new chronology indicates that grounded ice occupied Emerald Basin in the Late Wisconsinan.
Blue-green Algal Ammonia Uptake in Hypertrophic Prairie Lakes
Authors: Murphy T. P. , Brownlee B. G.
Published: June 2008

Within 24 h of an increase in lake [Formula: see text] concentration, [Formula: see text] uptake by Aphanizomenon flos-aquae and Microcystis aeruginosa increases much beyond the capacity predicted by Michaelis–Menten kinetic studies. In hypertrophic lakes this response enables these blue-green algae to optimize ammonia uptake during large oscillations of [Formula: see text] concentration, to aid them in competing with other algae, and to conserve [Formula: see text] within the ecosystem. Nitrogen limitation in the hypertrophic prairie lakes is a rare event.Key words: ammonia uptake, prairie lakes, nitrogen limitation, nitrogen cycle
Salt and Heat Budgets for the Gulf of St. Lawrence
Authors: Bugden G. L.
Published: June 2008

A simple box model expressing conservation of salt, heat, and mass for the top 50 m of four regions of the Gulf of St. Lawrence was developed. All available temperature and salinity data were combined with monthly estimates of freshwater input and surface heat flux to obtain an idea of the average annual variation in vertical and horizontal exchanges for the period March through December. Calculated horizontal transports agreed very well with available geostrophic calculations, and nutrient fluxes implied by the calculated upwelling of water from below 50 m are capable of supporting the estimated primary production in the Estuary and Northwestern Gulf. The main effect of the increasing freshwater discharge and surface heat flux in the spring seems to be a decrease in eddy exchange between the surface and deeper layers due to increased stratification.Key words: upwelling, horizontal transport, nutrient flux
Interpretation of Radiophosphate Dynamics in Lake Waters
Authors: Fisher T. R. , Lean D. R. S.
Published: June 2008

Models of planktonic phosphorus dynamics over the last 30–40 yr depend on the steady-state distribution of isotope for the determination of compartment size. Radiophosphate data for P-deficient lakes in summer have shown a steady-state distribution of 1–15% of 32P in the filtrate within 0.5–5 h. To explain this, a phosphate back-flux term from the particulate fraction has been widely accepted (phosphate is believed to be released from the internal pools of phosphate consumers and by excretion from herbivores and bacterivores). We show that dialysis of lake water at isotopic steady state provides values for the dissolved [32P]PO4 compartment up to an order of magnitude lower than those obtained by membrane filtration and gel filtration chromatography. This apparently occurs as a result of minor cell damage during filtration when most of the [32P]PO4 is in the particulate pool. Consequently, the size of the phosphate pool and the magnitudes of phosphate uptake and back-flux may have been overestimated by up to a factor of 10. Furthermore, the turnover time of the particulate compartment lengthens from ~ 40 min to > 1 d, which is more consistent with models describing P fluxes between functional components of the plankton.
Season and Body Size Influence Movement of Hydropsychid Caddisfly Larvae (Trichoptera: Hydropsychidae)
Authors: Kerans B. L.
Published: June 2008

Movement patterns of fifth-instar Hydropsyche slossonae larvae were investigated in artificial streams. In the first choice experiment, larvae were released into a central area and their upstream or downstream crawling or drifting was monitored. A second experiment used the same design; however, fifth instars collected during spring and fall were divided into two, nonoverlapping, relative size-classes (large and small) to determine how these factors influenced movement parameters. In both experiments, larvae always drifted more frequently than they crawled, but in experiment 2, drifting tendency declined with increasing weight in spring. In both experiments, there was no statistically detectable directional bias to crawling nor change in relative crawling direction with season or size-class. In experiment 2, drifting larvae were lighter than nondrifting larvae in the large size-class, but equal in weight in the small size-class. This result was unrelated to absolute weight, as large size-class larvae in fall were similar in weight to small size-class larvae in spring. It is possible that the relative weight differential of drifting and nondrifting larvae in one size-class but not the other may be related to sexual rather than body size differences.
In vitro Cultivation of Contracaecum osculatum (Nematoda:Anisakidae) from Third-Stage Larvae to Egg-Laying Adults
Authors: Likely C. G. , Burt M. D. B.
Published: June 2008

Third-stage (L3) Contracaecum sp. larvae, from Gadus morhua, developed to sexual maturity in a two-step roller culture system using medium API-1 supplemented with 5 mM L-cysteine only (step 1) and with bovine haem (Fildes' reagent) added (step 2). The gas phase was 85% N2 – 10% CO2 – 5% O2 and the culture was maintained at 35 °C. The mature nematodes proved to be Contracaecum osculatum, a species which normally matures in the stomach of pinnipeds.
Lipid Condition and Survival in Shrimp (Pandalus borealis) Larvae
Authors: Ouellet Patrick , Taggart Christopher T. , Frank Kenneth T.
Published: June 2008

Groups of shrimp (Pandalus borealis) larvae were reared under different food concentrations and types to assess changes in condition and survival during development. As expected, rate of growth (wet weight) was higher for larvae fed on 300 Artemia nauplii∙L−1 (San Francisco strain: 0.0528 mg∙d−1) Canada strain: 0.0355 mg∙d−1) compared with those reared at 150 nauplii∙L−1 (San Francisco strain: 0.0211 mg∙d−1), larvae fed Isochrysis cells only, and no food. Shrimp larvae reared without food and larvae fed on Isochrysis cells showed a decreasing trend in wet weight during development and did not survive beyond stage II. The triacylglycerol (TAG) content of larvae accumulated rapidly during the initial phase of intermoult followed by a decline to a minimum coincident with ecdysis. High mortality (average 2.2%∙d−1) occurred during the first phases of development (first 25 d) for all rations. Differences among experiments in the magnitude of the mortality (from 0.86 to 4.66%∙d−1) at the first moult were related to the proportion of larvae in poor TAG condition. The results are consistent with the concept that the TAG condition index can be used to forecast, on a relative basis, differential survival among larval groups.
Phototrophic Picoplankton in Lakes Huron and Michigan: Abundance, Distribution, Composition, and Contribution to Biomass and Production
Authors: Fahnenstiel Gary L. , Carrick Hunter J.
Published: June 2008

The phototropic picoplankton communities of Lakes Huron and Michigan were studied from 1986 through 1988. Abundances in the surface-mixed layer ranged from 10 000 to 220 000 cells∙mL−1 with a seasonal maximum during the period of thermal stratification. During thermal stratification, maximum abundances were generally found within the metalimnion/hypolimnion at depths corresponding to the 0.6–6.0% isolumes. The picoplankton community was dominated by single phycoerythrin-containing (PE) Synechococcus (59%) with lesser amounts of chlorophyll fluorescing cells (21%), PE colonial Synechococcus-like cells (11%), other PE colonial Chroococcales (6%), and other cells (3%). Single PE Synechococcus was abundant throughout the year whereas chlorophyll-fluorescing and colonial cyanobacteria were more abundant during the periods of spring isothermal mixing and summer stratification, respectively. Picoplankton accounted for an average of 10% (range 0.5–50%) of phototrophic biomass. Phototrophic organisms that passed 1-, 3-, and 10-μm screens were responsible for an average of 17% (range 6–43%), 40% (21–65%), and 70% (52–90%) of primary production. Maximum contributions of < 1, < 3, and < 10 μm size fractions occurred during the period of thermal stratification. Primary production by phototrophic picoplankton was found to equal production in the < 1 μm size fraction.
Confounding of Gear Selectivity and the Natural Mortality Rate in Cases where the Former is a Nonmonotone Function of Age
Authors: Thompson Grant G.
Published: June 2008

An "exponential–logistic" selectivity function is presented in which a single parameter (γ) determines whether gear selectivity is asymptotic (γ = 0) or reaches a maximum at finite age (γ > 0). The function is used to develop a model in which both γ and the natural mortality rate M are formally indeterminate and in which the coming year's catch limit can be viewed as a response function of either estimated γ or estimated M. Decision theory is then used to derive the optimal catch. The optimal catch is shown to increase with the degree of uncertainty surrounding M, although this conclusion may depend on the short managerial time frame assumed. Three "suboptimal" strategies are also considered: (1) setting catch at the level corresponding to the expected value of M, (2) setting catch at the minimum of the response function, and (3) setting catch at the level corresponding to γ = 0. The first suboptimal strategy never results in a catch greater than the optimum and always results in a lower expected loss than the second. The performance of the third strategy (relative to the others) depends on parameter values.
Fishing Tactics in a Two-Species Fisheries Model: The Bioeconomics of Bycatch and Discarding
Authors: Sampson David B.
Published: June 2008

The selections for fishing location largely determine the species mix and value of a fisher's catch. Because of travel costs, these choices also determine the profitability of a fishing trip. This paper develops a simple theoretical model for the selection of fishing locations by a fisher faced with two co-occurring species whose densities vary with distance from port. For each species there can be different catchability coefficients, handling times, and prices. The duration of each fishing trip is assumed fixed. The model is used to determine the profit-maximizing fishing tactics (the fishing locations and time spent at each location) and to explore the conditions that generate deliberate bycatch and discarding when one of the species cannot be sold because it is unmarketable or because of trip limits.
Roles of Nutrients in Controlling Growth of Epilithon in Oligotrophic Lakes of Low Alkalinity
Authors: Turner Michael A. , Howell E. Todd , Robinson Gordon G. C. , Campbell Paul , Hecky Robert E. , Schindler Eva U.
Published: June 2008

The ability of nutrients to control photosynthesis was compared in epilithon (the association on rock surfaces in the littoral zone) and phytoplankton of 13 low alkalinity lakes of the Experimental Lakes Area of northwestern Ontario. The study included (1) surveys of lakes varying in nutrient concentrations; (2) experimental additions to lakes of carbon and nitrogen (N), with or without phosphorus (P); and (3) experimental additions to lakes of sulfuric and nitric acids. Nutrient controls of planktonic and epilithic algal photosynthesis differed consistently. Phosphorus limited planktonic algal photosynthesis. In contrast, dissolved inorganic carbon (DIC) limited epilithic photosynthesis in both perturbed and unperturbed lakes because diffusive resistance kept the effective supply of DIC below the level needed for optimal growth. Epilithic photosynthesis was lowered when lake disturbances (e.g., acidification) reduced epilimnetic concentrations of DIC. Expected increases in atmospheric carbon dioxide can, therefore, differentially affect the littoral and pelagic food webs in low DIC lakes. Epilithic photosynthesis in all study lakes was unrelated to N or P availability despite apparent N and P deficiencies, based upon particulate nutrient ratios. Rates of epilithic respiration were, however, correlated with epilimnetic concentrations of inorganic N.
Phenotypic Divergence of Sea-ranched, Farmed, and Wild Salmon
Authors: Fleming Ian A. , Jonsson Bror , Gross Mart R.
Published: June 2008

We quantified divergence in phenotype of sea-ranched, farmed, and wild Atlantic salmon (Salmo salar) of a common genetic stock (River Imsa, Norway). These first-generation fish were also contrasted with a fifth-generation farmed population (Norwegian commercial strain) and with wild and multigeneration sea-ranched populations of coho salmon (Oncorhynchus kisutch). In comparisons using mature Atlantic salmon male parr, cultured juveniles had smaller heads and fins and narrower caudal peduncles and could be distinguished from wild juveniles with 100% accuracy. When juveniles were reared to adulthood in the natural marine environment, some environmentally induced differences due to juvenile hatchery rearing persisted but many disappeared. This was particularly true for head and trunk morphology. Greater adult divergence from the wild state was observed in multigeneration sea-ranched coho salmon, suggesting that evolutionary changes may accumulate with time. Continued farming of salmon juveniles through adulthood increased environmentally induced phenotypic divergence considerably. Both rayed-fin sizes and body streamlining decreased. Fifth-generation Norwegian farmed salmon showed the greatest morphological differences. Both the proportion of a fish's life history and number of generations spent in culture are thus probably important determinants of phenotypic divergence of cultured fish from their wild state.
Fecundity of the ocean shrimp (Pandalus jordani)
Authors: Hannah Robert W. , Jones Stephen A. , Long Michele R.
Published: June 2008

Fecundity of the ocean shrimp Pandalus jordani was analyzed from eight samples from the years 1989–1993 and compared with historical fecundity data for this species. Linear regressions of loge fecundity on loge carapace length from the 1989–1993 samples had significantly different slopes. Interannual variation in fecundity exceeded that found between areas within the same year, making it difficult to determine if the observed variation in fecundity resulted from geographic location or interannual variation. No consistent differences between the length–fecundity relationships of the recent and historical samples were demonstrated. A graphical comparison of fecundity with sea level height data provided preliminary evidence that sea bottom temperature may be influencing shrimp fecundity. Egg production, estimated from the length–fecundity relationships and from size and sex composition data from the commercial catch, showed wide variation between years and areas. Variation in sex composition explained roughly 62% of the variation in egg production. Egg production estimates, derived from a pooled length–fecundity relationship, deviated from estimates based on the individual samples by ± 13–18%. These deviations were considered to be a minor source of added variance when compared with other sources of variation in the total egg production of ocean shrimp.
Limits to tolerance of temperature and salinity in the quagga mussel (Dreissena bugensis) and the zebra mussel (Dreissena polymorpha)
Authors: Spidle Adrian P. , May Bernie , Mills Edward L.
Published: June 2008

The quagga mussel (Dreissena bugensis) and the zebra mussel (Dreissena polymorpha) were exposed to varied levels of salinity and temperature in the laboratory to compare the tolerance of each species to environmental stress. The zebra mussel could tolerate 30 °C for extended periods and higher temperatures (< 39 °C) for a period of hours depending on the acclimation temperature and the rate of temperature change. The upper thermal limit of the quagga mussel may be as low as 25 °C. Mussels of both species acclimated to 5 °C were less able to survive at high temperatures (30–39 °C) than mussels acclimated to 15 or 20 °C. The reduced upper temperature limit of the quagga mussel implies that it will not be able to expand as far south in North America as has the zebra mussel. Both D. bugensis and D. polymorpha were exposed to three concentrations of NaCl (5, 10, and 20‰) to test salinity tolerance. No individuals of either species survived beyond 18 days in salinities of 5‰ or higher. No interspecific difference occurred in salinity-induced mortality rate.
Differences in habitat utilization among native, native stocked, and non-native stocked brown trout (Salmo trutta) in a hydroelectric reservoir
Authors: Hesthagen T. , Hegge O. , Skurdal J. , Dervo B. K.
Published: June 2008

Native and native-stocked brown trout (Salmo trutta) in Lake Tesse, a regulated hydroelectric reservoir (southern Norway), were spatially segregated according to size: small individuals occurred mainly in the epibenthic habitat and larger individuals mainly in the pelagic habitat. In contrast, all size groups of non-native stocked brown trout were mostly restricted to the epibenthic habitat. Age-specific lengths were generally larger for non-native than for native stocked trout, which were larger than native fish. However, growth rate between age 3 and 4 was significantly lower for non-native stocked fish than for native and native stocked fish. Differences in body length were mainly due to strain but also to some extent to habitat. Native fish had significantly fuller stomachs in the pelagic than in the epibenthic habitat in summer. Epibenthic non-native fish had significantly fuller stomachs than native and native stocked fish in August but not in July. Native and native stocked fish fed mainly on surface insects and planktonic crustaceans in both habitats. We hypothesize that the non-native brown trout stocked in Lake Tesse do not use the pelagic habitat in the home lake and are therefore less adapted to utilize such habitat than populations originating from lakes where pelagic habitat is available.
Spring flood: a primary cue for hatching of river spawning Coregoninae
Authors: Næsje Tor , Jonssons Bror , Skurdal Jostein
Published: June 2008

Increased water discharge during spring floods gives the primary cue for the start of hatching and drift of European vendace (Coregonus albula) and whitefish (Coregonus lavaretus) in the Norwegian River Lâgen. The drift increased with water flow for discharges between 50 and 850 m3∙s−1(vendace: R2 = 0.91; whitefish: R2 = 0.77). The length of hatching period, as judged from the drift, was negatively correlated with the increase in water discharge (vendace: R2 = 0.73; whitefish: R2 = 0.68). The length of the egg incubation period and time of hatching were not significantly correlated with the ambient water temperature. Two artificial floods (220 m3∙s−1), released before normal spring flooding, increased the total number of drifting Coregoninae larvae in the river. The first flood increased the number of vendace and whitefish larvae per second from 2.1 and 0.0 to 86.1 and 4.5, respectively, before returning to preflood levels. The second flood gave 18.9 and 1.8 individuals/s.
Pleistocene refuge areas and postglacial dispersal of copepods of the northeastern United States
Authors: Stemberger Richard S.
Published: June 2008

The distribution of common freshwater copepods of the northeastern United States has a marked association with major meltwater drainage systems and coastal marine submergence zones formed during the retreat of the Wisconsinan ice sheet. Postglacial dispersal routes inferred from the deglaciation chronology indicate that zooplankton could have come from several major Pleistocene refuges in the Mississippi Valley, Appalachian Plateaus, and mid-Atlantic Coastal Plain, and from northern locations on the Atlantic Coastal Plain. Contemporary distribution patterns suggest that some species of copepods dispersed primarily in surface waters during advances and retreats of continental glaciers. These include species of the calanoid Skistodiaptomus and the cyclopoid Diacyclops thomasi that occur in coastal lowlands and in lower elevation lakes in mountainous areas that could be flooded by retreating ice-front lakes. There is little evidence, except for inadvertent introductions through human activities, that these species have expanded beyond their original postglacial dispersal boundaries. In contrast, other calanoid and cyclopoid species were widely distributed and are dominant in high-elevation lakes and lowland lakes behind mountain barriers unreachable by species dependent on water transport. These species commonly occur in permanent and temporary ponds and may produce dormant stages that are readily dispersed.
Growth characteristics of bloom-forming filamentous green algae in the littoral zone of an experimentally acidified lake
Authors: Turner Michael A. , Sigurdson Leif J. , Findlay David L. , Howell E. Todd , Robinson Gordon G. C. , Brewster John F.
Published: June 2008

Filamentous green algae, predominantly Mougeotia and Zygogonium, bloom frequently in the littoral zones of acidified lakes. Growth characteristics of Zygogonium-dominated filamentous green algae were studied for 4 yr in an experimentally acidified (pH 4.5) lake at the Experimental Lakes Area of northwestern Ontario. They were present in low abundance as periphyton (algal associations attached to surfaces) during spring, and as blooms of metaphyton (benthic algae unconstrained by surfaces) beginning in midsummer and reaching a maximum in early fall. Metaphytic filamentous green algae displayed high photosynthetic capacity in summer despite the oligotrophic nature of the acidified lake. The major factors controlling photosynthetic rates of Zygogonium were similar to those controlling Mougeotia, and included algal crowding, irradiance, dissolved inorganic carbon, and water temperature. Rates of photosynthesis were negatively dependent upon algal crowding, so that highest rates were associated with minimum algal crowding. Light requirements for photosynthesis were higher than those of the epilithon, which were dominant prior to acidification. The dependence of photosynthesis on ambient concentrations of dissolved inorganic carbon was partly regulated by water temperature. Anthropogenically caused releases from growth limitations (e.g., increased availability of limiting nutrients, increased water temperature, and extension of the growing season) may cause proliferation of filamentous green algae in the future.
Cone penetration testing in snow
Authors: Schaap Leo H. J. , Föhn Paul M. B.
Published: June 2008

The application of the electric cone penetrometer test in snow has been investigated and compared with results from the ram penetrometer test, which is normally used for snow profiling and slope stability analysis. A special cone penetrometer system was built consisting of a sensitive 1 cm2 electric cone, depth transducer, and battery-operated chart recorder. The instruments were tested in April 1985 at three different locations in the Swiss Alps and the test results were compared with those of the ram penetrometer tests.The tests yielded repeatable results up to a depth of 4 m with a high resolution of different snow layers. The electric cone tests show more layers than found in the ram profile and snow pit analyses. In soft snow the ram resistances appear to be, on average, about 30% lower than cone resistance values. Recommendations are given for the future use of electric cone penetration testing in snow. Key words: snow, snowpack analysis, cone penetration test, ram penetrometer, cone resistance, ram resistance, ram number.
Independence of geostatic stress from overconsolidation in some Beaufort Sea clays
Authors: Jefferies M. G. , Crooks J. H. A. , Becker D. E. , Hill P. R.
Published: June 2008

Since 1982, extensive use has been made of the self-bored pressuremeter in Arctic offshore site investigations. One finding of this work is that the in situ geostatic stress ratio K0 of Beaufort Sea clays is apparently unrelated to the overconsolidation ratio (OCR). The procedures and data to support this finding are documented and the finding is discussed in light of the present geological understanding for the area. It is concluded that the independence of K0 from OCR may be quite widespread, a finding that contradicts the widely held tenet regarding the existence of a single-valued function relating K0, [Formula: see text], and OCR. If K0 is regarded as important, then it should be measured in situ. Key words: self-bored pressuremeter, geostatic stress ratio (K0), Beaufort Shelf, geologic history, overconsolidation ratio.
Soil parameters for deformation analysis of sand masses
Authors: Byrne P. M. , Cheung H. , Yan L.
Published: June 2008

Meaningful stress and deformation analysis of soil structures requires an adequate stress–strain law. Herein are presented guidelines for selection of parameters for a simple incremental hyperbolic stress–strain law for sand based upon a tangent stiffness that varies with stress level. The parameters are obtained from an examination of laboratory and field measurements available in the literature, and are presented in terms of both penetration value and relative density. The laboratory results indicate the importance of first-time or primary loading versus repeated loading on modulus values. Back analysis of field observations for monotonic loading conditions indicates that primary loading modulus values obtained from triaxial tests are appropriate at low relative density, whereas perhaps higher values, in the repeated loading range, are appropriate at high relative densities. Key words: sand, deformation, analysis, hyperbolic, tangent stiffness, modulus, relative density, monotonic loading, repeated loading.
Geostatistical approach to the study of induced damage around underground rock excavations
Authors: Ouellet J. , Gill D. E. , Soulié M.
Published: June 2008

The problem of nuclear waste disposal has emphasized the need for research on blast-induced damage around underground excavations. This paper shows how geostatistical methods might be used to delineate zones of damage when the systematic rock testing approach is used. Some basic concepts of the theory of regionalized variables are presented and then illustrated by a typical application. The conclusions drawn from the latter using the theory of regionalized variables are quite different from those drawn from a previously published study based on the same data but using conventional statistical methods. Key words: rock mechanics, regionalized variable, induced damage, geostatistics, dilatometer.