bluuebunny/crossref_metadata_2025 huggingface dataset:
Discordancy or template-based recognition? Dissecting the cognitive basis of the rejection of foreign eggs in hosts of avian brood parasites
Authors: Moskát Csaba , Bán Miklós , Székely Tamás , Komdeur Jan , Lucassen Rim W. G. , van Boheemen Lotte A. , Hauber Márk E.
Published: May 2010

Many avian hosts have evolved antiparasite defence mechanisms, including egg rejection, to reduce the costs of brood parasitism. The two main alternative cognitive mechanisms of egg discrimination are thought to be based on the perceived discordancy of eggs in a clutch or the use of recognition templates by hosts. Our experiments reveal that the great reed warbler (Acrocephalus arundinaceus), a host of the common cuckoo (Cuculus canorus), relies on both mechanisms. In support of the discordancy mechanism, hosts rejected their own eggs (13%) and manipulated (‘parasitic’) eggs (27%) above control levels in experiments when manipulated eggs were in the majority but when clutches also included a minority of own eggs. Hosts that had the chance to observe the manipulated eggs daily just after laying did not show stronger rejection of manipulated eggs than when the eggs were manipulated at clutch completion. When clutches contained only manipulated eggs, in 33% of the nests hosts showed rejection, also supporting a mechanism of template-based egg discrimination. Rejection using a recognition template might be more advantageous because discordancy-based egg discrimination is increasingly error prone with higher rates of multiple parasitism.
Influence of confidence inflation and explanations for changes in confidence on evaluations of eyewitness identification accuracy
Authors: Paiva Melissa , Berman Garrett L. , Cutler Brian L. , Platania Judith , Weipert Ryan
Published: May 2010

Guidelines for conducting police line‐ups typically recommend immediate assessment of eyewitness confidence following identification. This confidence level can presumably be used to estimate accuracy even in the presence of subsequently inflated confidence. In this experiment, we examined students' perceptions of immediate and inflated confidence and whether their reliance on confidence varies as a function of the explanations given by the eyewitness for her inflated confidence. Each of 126 university students viewed one of five versions of a videotaped officer–eyewitness interaction depicting an eyewitness identification and follow‐up interview in which the eyewitness gave a (1) high or (2) moderate level of confidence or inflated her confidence and gave a (3) confidence epiphany, (4) memory contamination, or (5) no explanation for the inflation. The memory contamination and confidence epiphany explanations led to lower ratings of identification accuracy as compared to the high‐confidence control condition, supporting the immediate confidence recommendation but in some ways contradicting previous research on this issue. The results suggest the need for further research to understand the conditions under which confidence inflation influences juror evaluations of eyewitness identification.
Trinuclear metal clusters in catalysis by terpenoid synthases
Authors: Aaron Julie A. , Christianson David W.
Published: May 2010

Terpenoid synthases are ubiquitous enzymes that catalyze the formation of structurally and stereochemically diverse isoprenoid natural products. Many isoprenoid coupling enzymes and terpenoid cyclases from bacteria, fungi, protists, plants, and animals share the class I terpenoid synthase fold. Despite generally low amino acid sequence identity among these examples, class I terpenoid synthases contain conserved metal-binding motifs that coordinate to a trinuclear metal cluster. This cluster not only serves to bind and orient the flexible isoprenoid substrate in the precatalytic Michaelis complex, but it also triggers the departure of the diphosphate leaving group to generate a carbocation that initiates catalysis. Additional conserved hydrogen bond donors assist the metal cluster in this function. Crystal structure analysis reveals that the constellation of three metal ions required for terpenoid synthase catalysis is generally identical among all class I terpenoid synthases of known structure.
Factors influencing hairpin oligonucleotide cyclization by the uncatalyzed alkyne-azide cycloaddition (AAC) reaction
Authors: El-Sagheer Afaf H. , Brown Tom
Published: May 2010

Cyclization of short hairpin oligonucleotides (ODNs) containing unactivated alkynes and alkyl azides produces triazole-linked products slowly in the absence of CuI catalysis. The factors affecting the rate of this cycloaddition reaction have been investigated on a variety of hairpin sequences. The reaction proceeds best at intermediate concentrations of sodium chloride, but is inhibited by phosphate and Tris buffers. It is accelerated by increasing the temperature provided that Watson–Crick base pairing can occur. The rationale for these observations is discussed.
‘Mind the Gap’: Effective Literacy Instruction for Indigenous Low-Progress Readers
Authors: Wheldall Kevin , Beaman Robyn , Langstaff Elizabeth
Published: May 2010

A large gap is evident between the reading and related skills performance of Aboriginal students compared with that of their nonindigenous peers and this gap increases over the primary years of schooling. In this study, 34 students attended a tutorial centre in Sydney for older low-progress readers in Years 5 and 6, for two school terms. All students were referred by their schools on the basis of their reading difficulty and low socioeconomic status. The parents of 14 of these students self-identified as being Aboriginal. All students received an intensive, systematic skills-based remedial reading and spelling program (mornings only) and were assessed on a battery of literacy measures both prior to and following the two term intervention. The pre and posttest raw scores on all measures were analysed to determine the efficacy of the program. The group as a whole made large and highly significant gains on all measures of reading accuracy, comprehension, single word reading, nonword reading, spelling and oral reading fluency. There were no significant differences in gain between the two subgroups indicating that the program of instruction was equally beneficial for both Aboriginal and non-Aboriginal students.
Characteristics of the Closest Relationships Between Children With Developmental Disabilities and Peers in Inclusive Settings
Authors: Webster Amanda A. , Carter Mark
Published: May 2010

Inclusive education has become more common in schools, and children with developmental disabilities have had greater opportunities to interact, and hopefully establish relationships with their typically developing peers. While the quality of friendships between typically developing children has been examined in detail, relatively little comparable data is available on children with developmental disabilities. The current study provided an examination of the characteristics of the closest relationships between children with developmental disabilities and peers in inclusive school settings. Twenty-five children with developmental disabilities aged between approximately 5 and 12 years participated. Using an interview instrument, the relationships of these children with 74 peers were examined across six dimensions. Overall, dyads were found to be high in Validation and Caring as well as Help and Guidance, followed by slightly lower levels of Companionship. Intimate Exchange was reported to be lower. Conflict among dyads was also low, and Conflict Resolution was reported to be high when problems did occur. There was a clear differentiation between the highest- and lowest-ranked dyads for children with a disability. Overall, the features of the relationships between children with disabilities and their highest-ranked peer appeared similar in nature to those previously reported between typically developing peers.
Tensile Properties of Sn-10Sb-5Cu High Temperature Lead Free Solder
Authors: Zeng Qiulian , Guo Jianjun , Gu Xiaolong , Zhu Qingsheng , Liu Xiaogang
Published: May 2010

The Sn-10Sb-5Cu high temperature lead free solder was developed, and the mechanical property of such bulk solder and the solder joint was investigated in the present work. The microstructure of the Sn-10Sb-5Cu bulk solder was composed of long strip-like Cu6Sn5 and square Sn3Sb2 intermetallic compounds (IMCs). In the solder joint, the IMCs were the same as in the bulk solder but with a much finer microstructure. The test results showed that the tensile properties of the Sn-10Sb-5Cu bulk solder were sensitive to the strain rate. The higher the strain rate, the higher the ultimate strength. The ductility after fracture was enhanced by lowering strain rates. The fracture elongation approached 6.5 % when the strain rate was 10−5/s. Compared with that of the bulk Sn-10Sb-5Cu solder, the tensile strength of the Sn-10Sb-5Cu/Cu solder joint was much lower. The joint showed excellent plasticity with a large nominal engineering strain of 80 % during tensile tests. The tensile strength of the solder joint decreased after some aging time. However, the strength remained at about 80 % of the original value after aging for 15 days at the temperature of 150°C. The difference in the tensile properties between bulk solder and solder joint resulted from the difference in microstructures. Coarser Cu6Sn5 IMC in the bulk solder led to the higher ultimate strength, and the finer Cu6Sn5 IMC in the solder joint resulted in much better fracture ductility of the solder joint.
A Study on the Influence of Measurement Procedures on Suction-Water Content Relationship of a Sandy Soil
Authors: Malaya C. , Sreedeep S.
Published: May 2010

Soil suction and its relationship with water content (gravimetric or volumetric) are inevitable in the study of unsaturated soil mechanics. Suction-water content relationship (designated as SWR) is an important input parameter for the mathematical modeling of unsaturated soil response pertained to physico-mechanical, hydraulic, and volume change behavior and hence needs to be accurate and unambiguous. There are two commonly adopted procedures for establishing the SWR. In the first method (designated as continuous measurement), continuous drying suction measurements are performed on the same soil sample, starting from a high water content (corresponding to insignificant suction), which is termed as soil-water characteristic curve. In the second method (designated as spot measurement), remolded soil samples are packed at different compaction states, varying in unit weight and water content, on which suction measurements are performed. It is noted that there is no comparison and critical evaluation of these two procedures adopted for determining SWR. Such a study is important as the particle rearrangement in the soil samples undergoing a drying process might be different from that of the reconstituted/remolded samples. Therefore, the present study attempts to understand the uniqueness of SWR obtained by using two procedures for a locally available sandy soil. In this study, tensiometer and a capacitance probe have been used for measuring suction and volumetric water content, respectively. The study indicates that SWR established by using different procedures may not be unique and there is a need to highlight it while reporting such relationship for the soil.
The global economic crises: Impacts on Eastern Europe
Authors: Marer P.
Published: May 2010

The global crisis of 2007–2009 can be viewed as three interdependent and mutually reinforcing crises: a financial crisis, a liquidity crisis, and a crisis in the real economy. The ten East European countries that are now EU members were hit first by the global liquidity crisis, then by dramatic declines in capital inflows and plunging demand for their exports. Different impacts among the ten are explained by such factors as their exchange rate regimes, the extent to which households found it advantageous to rely on foreign-currency loans and the appropriateness of fiscal and monetary policies prior to the crisis. Since Western Europe’s recovery and growth are likely to be slow, in the future East European countries will have to rely relatively more on internally-generated sources of productivity growth and enhanced global competitiveness.
Is the conflict container full? Problems of fiscal sustainability at the local government level in Hungary
Authors: Vigvári A.
Published: May 2010

The paper discusses the reasons and possible resolutions of the contradictions in the Hungarian local government system, and proposes methods to resolve them. The nature of the Hungarian system cannot be described by classical normative theories of fiscal federalism. The operation of Hungarian local governments is determined rather by the decentralisation of conflicts stemming from the reduction of state responsibilities, and the resulting municipal behaviour. The second generation theory of fiscal federalism pays particular attention to the institutional guarantees of fiscal discipline shown by the lower levels of government sector. Actors in the Hungarian system, a system that functions as a ‘conflict container’, try to offset the financial pressures, weighing heavily on them by borrowing and by contingent liabilities. While central government has transferred new duties to local governments from year to year, it has reduced the amount of fiscal subsidies. Until a long-term comprehensive reform is implemented, consequent risks must be treated in the short run, as well.
Bayesian estimation of the Okun coefficient for Romania
Authors: Caraiani P.
Published: May 2010

In this paper I use a New Keynesian model with unemployment and estimate it for the Romanian economy using Bayesian techniques. I use the estimated model to derive an estimation of the Okun coefficient. I alternatively estimate the Okun coefficient using the Bayesian linear regression. The results show that the Okun coefficient is high in the Romanian economy implying that the current crisis will have a severe impact on the labour market as well as important social effects.
Results of ENDORSE-2-HUNGARIA study. Repeated assessment of the prevalence of venous thromboembolism risk and prophylaxis in acute hospital care setting
Authors: Losonczy Hajna , Tar Attila
Published: May 2010

2006-ban az ENDORSE (nemzetközi epidemiológiai nap a vénás trombózis és embólia szempontjából veszélyeztetett betegek felmérésére az akut kórházi ellátásban) nemzetközi, obszervációs, keresztmetszeti vizsgálat célja a kórházban fekvő, vénás thromboembolia veszélyének kitett betegek prevalenciájának, valamint a hatásos profilaxisban részesülők arányának meghatározása volt. A 32 ország 358 véletlenszerűen beválasztott kórházában végzett globális regiszterben kilenc magyar vizsgálóhely vett részt. A magyarországi eredmények szerint a sebészeti betegek irányelvnek megfelelő profilaxisa felülmúlta a nemzetközi átlagot, de a belgyógyászati profilaxis jelentős mértékben alulmaradt. A trombózismegelőzés összehasonlítására két év és két hónap után hazánkban elvégezték az ENDORSE-2-HUNGARIA vizsgálatot. Mindkét felmérésben az American College of Chest Physicians 2004-es evidenciákon alapuló irányelvei szerint értékelték a trombózisrizikót, és megvizsgálták, hogy a betegek megkapták-e az irányelveknek megfelelő profilaxist. Az egynapos ENDORSE-2-HUNGARIA vizsgálatot a már felmért hét kórház mellett két újonnan beválasztott kórházban ismételték meg. A kórlapok alapján összesen 886 betegnél vizsgálták meg a vénásthromboembolia-kockázat fennállását. Vénás thromboembolia szempontjából a betegek 59,0%-a volt veszélyeztetett (N=523/886), közülük a sebészeti betegek 100%-a (N=327), a belgyógyászatiak 35,1%-a (N=196). A teljes trombóziskockázatú populációnak 67,9%-a (N=355) részesült az ACCP-irányelvek szerinti profilaxisban. Az ajánlásnak megfelelő profilaxist a sebészeti betegek közül 84,4% (N=276), a belgyógyászati betegek közül 40,3% (N=79) kapta meg. Összehasonlítottuk a 2006-os és 2009-es ENDORSE-adatokat. A hatásos profilaxisban részesült trombózisrizikójú sebészeti betegek aránya nem változott szignifikánsan, a belgyógyászati betegeknél 43,9%-os szignifikáns (p=0,002) növekedést találtunk, ami bizonyítja a két vizsgálat közötti idő alatt a tényeket bemutató és a belgyógyászati profilaxis növelésére fókuszáló előadások sikerét. Az ENDORSE-2-HUNGARIA eredményei szerint 2009-ben a vénástrombózis-kockázatú belgyógyászati betegek 59,7%-a, a sebészeti betegek 15,6%-a védtelen maradt a trombózissal szemben. További erőfeszítéseket kell tehát tennünk azért, hogy még több hospitalizált beteg részesüljön profilaxisban. Az egészségügyi dolgozók körében tovább kell növelni a hospitalizált belgyógyászati betegek trombóziskockázatának ismeretét, és törekednünk kell arra, hogy még szélesebb körben alkalmazzák a profilaxist.
Development and Evaluation of a Bioenergetics Model for Saugeye
Authors: Zweifel Richard D. , Landis Andrew M. Gascho , Hale R. Scott , Stein Roy A.
Published: May 2010

We parameterized and evaluated a bioenergetics model for saugeye (walleyeSander vitreus× saugerS. canadensis) by using laboratory experiments in an effort to improve predictions of prey consumption. First, we measured daily prey consumption rate and growth of age‐0 and age‐1 saugeyes fed two daily rations (ad libitum and 50% of maximum) at five temperatures ranging from 10°C to 28°C. Additional experiments quantified routine respiration rates and waste losses for three ages of saugeye (ages 0, 1, and 2) at five temperatures ranging from 10°C to 28°C. Mean daily rates of prey consumption (g·g−1·d−1) by saugeyes increased from 10°C to 25°C, declining at 28°C. Respiration rates (g O2·g−1·d−1) increased over the entire range of water temperatures. Waste losses were minor for saugeyes as egestion averaged 3.5% of consumed energy and energy lost via excretion was 4.5% of assimilated energy. We evaluated the accuracy of bioenergetics model predictions of saugeye prey consumption using daily prey consumption and corresponding growth data from our first set of experiments. Model estimates of prey consumption rates (g·g−1·d−1) closely followed observed trends, providing reasonable estimates of cumulative prey consumption across temperature and fish size. The saugeye model provided improved estimates of consumption compared with a model published for walleyes (Kitchell et al. 1977), especially when water temperatures were in excess of 25°C. The differences we observed in predictive performance between the two models resulted from higher thermal optima for saugeyes compared with walleyes, and waste constants for saugeyes were two to three times lower than those calculated from the walleye model. These differences may largely be responsible for the walleye model's overestimation of consumption. Saugeye thermal optima are warmer than those of either parent species, and saugeye is better suited for warm, productive midwestern U.S. reservoirs. The saugeye model developed herein will improve the ability of managers to more accurately predict the consumptive demand of in situ saugeye populations and better tailor stocking rates to match available prey biomass.
Temperature and Salinity Effects on Survival and Growth of Early Life Stage Shubenacadie River Striped Bass
Authors: Cook A. M. , Duston J. , Bradford R. G.
Published: May 2010

A series of short, laboratory‐based trials was conducted on striped bass Morone saxatilis from the Shubenacadie River, Nova Scotia, Canada, starting with wild‐caught eggs and proceeding through to the early juvenile stage. The levels of the experimental factors—salinity (0–35‰) and temperature (10–30°C)—spanned the range occurring in the natal estuary. Survival of eggs to 1 d posthatch (dph) was highest, more than 60%, between 2‰ and 20‰ salinity and was reduced significantly (to <50%) only in salinities of 30‰ or greater. Similarly, survival of prefeeding larvae was reduced only at salinities above 30‰, suggesting that their salinity tolerance is higher than that of U.S. populations. Moreover, 1–7‐dph larvae were tolerant to temperature decreases that are lethal to other populations, with around 40% surviving between 10°C and 14°C at intermediate salinities. Older, 23‐dph larvae were less tolerant to cold, with fewer than 20% surviving 7 d at 10°C, but these larvae thrived at high temperature, exhibiting highest survival and growth at 26°C across salinities from 1‰ to 35‰. Growth of early juvenile stages (55–104 dph) was independent of salinity (1–30‰) and was highest between 26°C and 30°C, suggesting a temperature optimum similar to that of U.S. populations.
Sediment and Salmon: The Role of Spawning Sockeye Salmon in Annual Bed Load Transport Characteristics in Small, Interior Streams of British Columbia
Authors: Macdonald J. Stevenson , King Cher A. , Herunter Herb
Published: May 2010

The redd construction process of sockeye salmon Oncorhynchus nerka may be an important and unique component of bed load transport in some northern, interior British Columbia streams. Using pit trap samplers in four streams over 6 years, we examined bed load accumulation and size composition after three distinct periods: spring flood (high flow), salmon spawning (low flow), and winter (low flow). Bed load movement increased with stream velocity and more accumulated during the spring floods than during the winter. However, bed load accumulations were greater during the spawning period than during the winter at similar thalweg velocities. There was a significant influence of spawning fish density on the amount of bed load accumulated. The variability in bed load size composition was most attributable to the tendency for spawners to move proportionally more large material than was moved during the flood and winter periods, with a grain‐size distribution that was comparable to the source material in all but one of the creeks. Mobilization of intermediate‐size material distinguished the spring flood period from the low‐flow winter period but accounted for considerably less of the overall variation. Variability among years was minor. Relative to hydraulic factors, salmon spawning activities have a density‐dependent and unique influence on the mobilization of bed material in interior watersheds. We speculate that there is a positive feedback mechanism by which healthy salmonid stocks contribute to the maintenance of the small stream ecosystems on which they depend.
Accuracy of Using Scales to Age Mixed‐Stock Chinook Salmon of Hatchery Origin
Authors: McNicol Richard E. , MacLellan Shayne E.
Published: May 2010

Despite a long history of using scales to age Pacific salmon, there have been few attempts to validate scale‐derived ages. This is particularly true for Chinook salmon Oncorhynchus tshawytscha, a species exhibiting a wide range of life histories across stocks. This has led to continuing questions regarding the accuracy of scale‐based age determination for Chinook salmon. This study assessed the accuracy of Chinook salmon scale age data produced by multiple readers from multiple agencies, who aged hatchery fish of known age from mixed‐stock, nonterminal fisheries conducted along the Pacific coast of Canada from 1991 to 2003. The test sample consisted of scales from 434 fish from both stream‐ and ocean‐type stocks marked with coded wire tags (i.e., fish origin and total age were known). Sample stocks originated from Oregon, Washington, and British Columbia. Five readers from three federal or state Pacific Northwest fisheries agencies participated in the study. The readers possessed various levels of experience, which was classified as (1) deep or shallow (depth) depending on the number of years the reader was involved in aging Chinook salmon scales and (2) broad or narrow (breadth) depending on the variety of stocks the reader had previously encountered. Accuracy ranged from 84% to 94%, although readers with both deep and broad experience consistently achieved accuracies greater than 90%, while those with a narrower breadth of experience tended to show age bias. Overall, the results suggest that aging Chinook salmon scales from ocean‐caught hatchery fish can be accurate and that readers' previous exposure to stocks comprising a wide range of life history types may be at least as important as the number of years of experience in achieving a high level of aging accuracy.
A Simple Biomass‐Based Length‐Cohort Analysis for Estimating Biomass and Fishing Mortality
Authors: Zhang Chang Ik , Megrey Bernard A.
Published: May 2010

A biomass‐based length‐cohort analysis (LCA) was examined for its performance in estimating total stock biomass and fishing mortality (F) for a population in equilibrium. We compared two LCA methods—(1) a numbers‐based LCA that relies on catch numbers at length as input data and (2) a new biomass‐based LCA that relies on catch biomass at length—by applying both to simulated data that generally followed characteristics of Pacific chub mackerelScomber japonicusin Korean waters. We investigated the effects of using two length aggregation methods, two data simulation methods, and three expressions of weight growth (i.e., exponential growth over the length increment of the analysis, arithmetic mean growth, and geometric mean growth). Biomass andFwere estimated from the new model and compared with those estimated from the numbers‐based LCA model. A sensitivity analysis was performed to understand which aspect of the model parameters controlled the results. Sensitivity to estimates of terminalFwas also examined. Results of the analysis showed that the allometric power coefficient β was the most important model parameter and that sensitivity of biomass‐based LCA to terminalFwas similar to that of numbers‐based LCA. Monte Carlo simulation was used to evaluate the equilibrium assumption and to calculate confidence intervals for biomass estimates. We applied the biomass‐based LCA model to data for northern rock soleLepidopsetta polyxystrain the eastern Bering Sea. A comparison of biomass‐based LCA population biomass estimates with northern rock sole research survey biomass estimates showed good agreement between the two types of estimates. The biomass‐based LCA described in this study is unique in that it incorporates growth explicitly into the estimation procedure, which can be useful under data‐deficient situations when simple length composition data and estimates of total catch biomass from just one sampling year are the only available data.
Relative Importance of Water Temperature, Water Level, and Lunar Cycle to Migratory Activity in Spawning‐Phase Sea Lampreys in Lake Ontario
Authors: Binder Thomas R. , McLaughlin Robert L. , McDonald D. Gordon
Published: May 2010

We analyzed historical trapping records from six Lake Ontario tributaries to (1) compare the relative importance of water temperature, water level, and lunar cycle to migratory activity in upstream‐migrating sea lampreys Petromyzon marinus and (2) determine whether the relative importance of these variables differs among streams. We found significant stream‐dependent differences in the relative importance of the environmental variables. Water temperature was the best predictor of migratory activity in all six streams. The seasonal distribution of migratory activity was related to mean stream temperature, with an estimated peak migration temperature of approximately 15°C. Changes in stream temperature were equally as important. Migratory activity was stimulated when mean stream temperature increased between consecutive days and was suppressed when mean stream temperature decreased between consecutive days. Water level was a reliable predictor of migratory activity only in the two smallest streams. We hypothesize that high water levels may increase migratory activity in small streams by making them more noticeable. There was no evidence to support either a circumlunar rhythm or gravitational influence on migratory activity. However, because we did not account for cloud cover or the presence of artificial light sources, we cannot exclude the possibility that nighttime light levels influence migratory activity. Our findings provide a set of rules for coarsely projecting migratory activity in upstream‐migrating sea lampreys.
Population Dynamics of Larval Trematodes in Juvenile Bluegills from Three Lakes II, Michigan, and the Potential for Overwinter Parasite‐Induced Host Mortality
Authors: Pracheil Brenda M. , Muzzall Patrick M.
Published: May 2010

Prior studies of the population dynamics of larval trematodes infecting juvenile bluegills Lepomis macrochirus have suggested that there may be overwinter loss of the most heavily infected juvenile bluegills from the population. Our study objectives were to (1) describe population dynamics of the four most common larval trematodes—Cryptogonimus sp., Posthodiplostomum minimum, Diplostomum sp., and Neascus sp.—and the overall larval trematode burden for three year‐classes of juvenile bluegills in Three Lakes II, Michigan; and (2) assess the potential for larval trematode infections as a cause of first‐winter bluegill mortality based on changes in parasite overdispersion. We examined 393 juvenile bluegills for larval trematodes, and more than 99% of examined bluegills were infected with a parasite. Decreases in overdispersion of several larval trematode species in spring and summer 2003 may have been the result of larval trematode‐induced host mortality. The results of this study suggest that heavy larval trematode infections may be negatively influencing bluegill survival, particularly during and after winter. Additionally, this study demonstrates that population dynamics of larval trematodes in Three Lakes II are similar to those of trematodes found in the southeastern USA but that the larval trematodes in the present study may have a more negative effect on bluegill survival due to more harsh winter conditions.
Tail‐Beat Patterns in Dual‐Frequency Identification Sonar Echograms and their Potential Use for Species Identification and Bioenergetics Studies
Authors: Mueller Anna‐Maria , Burwen Deborah L. , Boswell Kevin M. , Mulligan Tim
Published: May 2010

We observed patterns in echograms of data collected with a dual‐frequency identification sonar (DIDSON) that were related to the tail beats of fish. These patterns reflect the size, shape, and swimming motion of the fish and also depend on the fish's angle relative to the axis of the beam. When the tail is large enough to reflect sound of sufficient intensity and the body is angled such that the tail beat produces periodic changes in the range extent covered by the fish image, then the tail beat becomes clearly visible on echograms that plot the intensity maximum of all beams. The analysis of DIDSON echograms of a mix of upstream‐migrating Chinook salmon Oncorhynchus tshawytscha and sockeye salmon O. nerka resulted in the separation of two groups: (1) fish of sockeye salmon size that swam with a tail‐beat frequency (TBF) between 2.0 and 3.5 beats/s and (2) fish of Chinook salmon size with a TBF between 1.0 and 2.0 beats/s. There was no correlation between TBF and fish size within each group, which suggests that the observed difference in TBF between the two groups was species‐specific rather than an indirect effect of the groups' difference in size. The technique of extracting TBF from DIDSON echograms may also be useful for bioenergetics studies. Compared with electromyogram telemetry, it offers the advantages of being nonintrusive and faster to set up and analyze and therefore is suitable for analyzing larger sample sizes. The disadvantages are that the technique's potential is limited to relatively large fish, it can cover only relatively small areas, it cannot be used to follow individual fish over long distances, and some environments are too noisy to produce DIDSON images of sufficient quality.
Do Nonnative Salmonines Exhibit Greater Density and Production than the Natives They Replace? A Comparison of Nonnative Brook Trout with Native Cutthroat Trout
Authors: Benjamin Joseph R. , Baxter Colden V.
Published: May 2010

The replacement of native species by nonnative species has been widely documented. In aquatic ecosystems, nonnative trout often replace native trout species to which they are closely related. For example, nonnative brook trout Salvelinus fontinalis have replaced native cutthroat trout Oncorhynchus clarkii throughout western North America. We hypothesized that when brook trout replace cutthroat trout, they exhibit greater density, biomass, and annual production than were achieved by the cutthroat trout before replacement. We tested this hypothesis in five paired streams in the Teton River drainage, Idaho, over a 4‐year period. Streams were paired based on similar habitat characteristics and the presence of brook trout or cutthroat trout as the dominant species. Fish were surveyed annually by means of multipass depletion along representative stream reaches. Consistent with our hypothesis, brook trout exhibited 2.4 times greater density, 1.7 times greater biomass, and 2.5 times higher annual production than cutthroat trout. Because age‐0 fish were difficult to capture during electrofishing, we also analyzed the data without this age‐class. When age‐0 fish were excluded, brook trout exhibited 1.3, 1.6, and 2.1 times greater density, biomass, and annual production, respectively, than cutthrout trout. These results are consistent with the hypothesis that nonnative salmonines exhibit greater density and production than the native fishes they replace, though the generality of this finding remains to be tested. The differences that we observed not only testify to the success of brook trout as an introduced species in western North America but also point to likely changes in ecosystem function that may accompany their replacement of native cutthroat trout.
Identification of Marine‐Derived Lipids in Juvenile Coho Salmon and Aquatic Insects through Fatty Acid Analysis
Authors: Heintz Ron A. , Wipfli Mark S. , Hudson John P.
Published: May 2010

The energetic benefits enjoyed by consumers in streams with salmon runs depend on how those benefits are accrued. Adult Pacific salmon Oncorhynchus spp. deliver significant amounts of nutrients (i.e., nitrogen and phosphorus) and carbon to streams when they spawn and die; these nutrient additions can have demonstrable effects on primary production in streams. Consumption of carcass tissues or eggs provides for direct energy subsidies to consumers and may have significant effects on their condition. In this study, comparisons of juvenile coho salmon O. kisutch and aquatic insects exposed to terrestrial and marine energy sources demonstrated that direct consumption of marine‐derived lipids had a significant effect on the lipid reserves of consumers. Direct consumption of marine‐derived tissues was verified through fatty acid analysis. Selected aquatic insects and juvenile coho salmon were reared for 6 weeks in experimental streams supplied with terrestrial or marine energy sources. Chironomid midges, nemourid stoneflies, and juvenile coho salmon exposed to the marine energy source altered their fatty acid compositions by incorporating the long‐chain polyunsaturated fatty acids that are characteristic of marine fish. The fatty acid composition of baetid mayflies was unaffected. The direct movement of specific fatty markers indicated that direct consumption of marine‐derived tissues led to increased energy reserves (triacylglycerols) in consumers. Similar results were obtained for juvenile coho salmon sampled from natural streams before and after the arrival of adult salmon runs. These data indicate that marine‐derived lipids from anadromous fish runs are an important source of reserve lipids for consumers that overwinter in streams.
Water Temperature and Prey Size Effects on the Rate of Digestion of Larval and Early Juvenile Fish
Authors: Legler Nicholas D. , Johnson Timothy B. , Heath Daniel D. , Ludsin Stuart A.
Published: May 2010

While predation is widely accepted as a major cause of mortality for fish larvae, its extent is largely unknown because few studies have been able to identify larvae in the stomach contents of predatory fish. Rapid digestion rates probably explain why fish larvae are rarely found in stomach contents, yet quantification of digestion rates of fish larvae is generally lacking, especially in freshwater systems. Using a series of laboratory experiments, we quantified the effects of temperature and larval fish (prey) size on digestion rate. We also evaluated whether species type (both predator and prey) influences digestion rate and described the morphological breakdown of fish larvae during digestion. Bluegills Lepomis macrochirus and yellow perch Perca flavescens were force‐fed the larvae of guppies Poecilia spp., rainbow trout Oncorhynchus mykiss, and yellow perch at a range of temperatures (7–22°C), and digestion rates were measured using prey mass before and after digestion (i.e., proportional loss of prey mass after ingestion). As expected, digestion rates increased with water temperature and decreased with prey body mass but were unaffected by species of predator. A confounding effect of prey type (fresh versus frozen) prevented a thorough evaluation of prey species, although yellow perch and rainbow trout (both previously flash‐frozen) were digested at similar rates. The complete breakdown of larvae in predator stomachs and the loss of morphological characters needed to identify larvae occurred rapidly, confirming the challenges of evaluating predation mortality based on stomach contents of field‐collected predators. Ultimately, our findings can be used to help researchers quantify the likelihood of detecting larval fish in the stomachs of field‐caught predators when using conventional stomach content analyses.
Osteoporosis and inflammation
Authors: Lacativa Paulo Gustavo Sampaio , Farias Maria Lucia Fleiuss de
Published: May 2010

Several inflammatory diseases such as rheumatoid arthritis, systemic lupus erythematosus, inflammatory bowel disease, celiac disease, cystic fibrosis and chronic obstructive pulmonary disease have been associated to bone resorption. The link between osteoclast, macrophage colony stimulating factor and pro-inflammatory cytokines, especially tumor necrosis factor-α and interleukin-1 explain the association between inflammation and osteoporosis. These diseases are related to osteoporosis and high fracture risk independent of other risk factors common to inflammatory diseases such as reduced physical activity, poor nutritional status, hypovitaminosis D, decrease in calcium intake and glucocorticoid treatment. Erythrocyte sedimentation rate and C-reactive protein should always be performed, but the indication about when to perform the densitometry test should be analyzed for each disease. Bisphosphonates are nowadays the best choice of therapy but new medications such as denosumab, IL-1 receptor antagonist, and TNF-α antibody have risen as new potential treatments for osteoporosis secondary to inflammation.
Bone mineral density in HIV-infected women taking antiretroviral therapy: a systematic review
Authors: Carvalho Érico Higino de , Gelenske Thais , Bandeira Francisco , Albuquerque Maria da Fátima Pessoa Militão de
Published: May 2010

There is a high prevalence of osteoporosis in HIV-infected patients. Initially described in HIV-positive men, studies have also demonstrated a high prevalence of osteoporosis in HIV-infected women. It would appear that antiretroviral therapy (ART) plays an important role in the pathogenesis of osteoporosis in HIV-infected patients, although little is known about its importance in relation to osteoporosis and fractures in HIV-positive women. The aim of this systematic review was to evaluate the frequency of bone loss, bone mineral density (BMD) and fractures in HIV-positive women taking ART or protease inhibitors (PI). After screening 597 citations from the databases of PubMed, EMBASE and Lilacs, five studies were selected for the review. A difference was demonstrated of over 3% in the BMD at the femoral neck of HIV-positive women taking PI/ART. No difference was registered in the BMD at the lumbar spine between users and non-users of PI/ART. The lack of studies has made it impossible to reach any conclusion regarding the occurrence of fractures.
Nutritional aspects of the prevention and treatment of osteoporosis
Authors: Peters Bárbara Santarosa Emo , Martini Lígia Araújo
Published: May 2010

Osteoporosis is a global health problem characterized by low bone mass and microarchitectural deterioration of bone tissue with a consequent increase in bone fragility and susceptibility to fracture. Nutrition plays a critical role in reducing the risk of osteoporosis through its effect on all of these fragility factors, especially on the development and maintenance of bone mass. An adequate calcium, vitamin D and protein intake resulted in reduced bone remodeling, better calcium retention, reduced age-related bone loss, and reduced fracture risk. Recent evidence indicates that a healthy dietary pattern including dairy products (mainly fat free), fruit and vegetables and adequate amounts of meat, fish and poultry is positively related to bone health. Furthermore, mineral and vitamin supplementation should be closely monitored by health professionals since it could have adverse effects and be insufficient to ensure optimal protection of bone health.
Bisphosphonates in the treatment of metabolic bone diseases
Authors: Arantes Henrique Pierotti , Silva André Gonçalves da , Lazaretti-Castro Marise
Published: May 2010

Osteoporosis is a disease characterized by low bone mass associated with the deterioration of microarchitecture, due to an imbalance either in high bone resorption or low bone formation or in both, leading to a high risk of fractures. Bisphosphonates are medications which reduce the ability of osteoclasts to induce bone resorption and consequently improve the balance between resorption and formation. There are bisphosphonates approved for the prevention and treatment of osteoporosis. Administration can be oral (daily, weekly or monthly) or intravenous (quarterly or yearly). These medications are well tolerated and with the correct instructions of administration have a good safety profile. Serious side effects, such as, osteonecrosis of jaw is very rare. Bisphosphonates are the most prescribed medication for the treatment of osteoporosis.
Factors associated with secondary hyperparathyroidism in premenopausal women undergoing Roux-en-Y gastric bypass for the treatment of obesity
Authors: Vasconcelos Renata Simões de , Viégas Maíra , Marques Thyciara Fontenele , Diniz Erik Trovão , Lucena Cynthia Salgado , Câmara Neto José Bezerra , Bandeira Francisco
Published: May 2010

OBJECTIVE: To evaluate bone metabolism, bone density (BMD) and vertebral fractures in morbidly obese individuals. SUBJECTS AND METHODS: Case series of 29 premenopausal obese patients, 15 of whom had been submitted to bariatric surgery. Serum calcium, albumin, PTH and 25-hydroxy vitamin D (25OHD) were measured as well as bone densitometry of the lumbar spine and proximal femur, and lateral spine x-rays. RESULTS: High parathyroid hormone (PTH) levels were recorded in 46.6% of the surgical patients and in 21.4% of the non-surgical patients (p = 0.245); 26.7% of the former and 28.6% of the latter revealed levels 25OHD < 30 ng/mL (p = 1.000). Calcium intake was higher in the surgical group (p = 0.004) along with lower serum calcium concentrations (p = 0.019). There were no significant differences in bone mineral density (BMD) or in the prevalence of vertebral fractures between groups. CONCLUSION: In premenopausal women undergoing Roux-en-Y gastric bypass there is important intestinal calcium mal absorption which seems to be the main factor causing secondary hyperparathyroidism.
Bioavailability of vitamin D3 in non-oily capsules: the role of formulated compounds and implications for intermittent replacement
Authors: Coelho Iara Maria Gomes , Andrade Luena Dias de , Saldanha Lunnara , Diniz Erik Trovão , Griz Luiz , Bandeira Francisco
Published: May 2010

OBJECTIVE: To evaluate the bioavailability of vitamin D in capsules as compared with oily drops in nuns living in a closed community with very low sun exposure. METHODS: A randomized, 2 x 2 crossover, open clinical trial was conducted, with 18 nuns aged between 20 and 75 years. Samples were collected in the fasting state and at 4, 8, 12 and 24 hours following the administration of capsules and oily drops (both containing vitamin D3 66,000 UI plus vitamin A 13,200 UI) to determine serum 25 hydroxivitamin D concentrations (25OHD), at baseline and 90 days after. The evaluation was based on the maximum concentration (Cmax) and area under the curve (AUC0-24). RESULTS: The capsule formulation presented Cmax and AUC0-24, 5.78% and 0.76%, respectively, greater than the oily drops formulation. CONCLUSION: Both formulations were within the limits for a bioequivalence study, namely C-90% for Cmax and AUC0-24, and the drugs were considered bioequivalent.
Short-term bone marker responses to teriparatide and strontium ranelate in patients with osteoporosis previously treated with bisphosphonates
Authors: Sousa Isabel Oliveira de , Diniz Erik Trovão , Marques Thyciara Fontenele , Griz Luiz , Coutinho Mário de Almeida Pereira , Bandeira Francisco
Published: May 2010

OBJECTIVE: To evaluate the responses of serum β-CTX and osteocalcin in patients who were undergoing treatment with teriparatide or strontium ranelate (SR). SUBJECTS AND METHODS: We analyzed 14 patients (12 women and 2 men; mean age of 71 years) taking teriparatide, and 13 female patients (mean age of 70 years) taking SR; all the patients having previously been on bisphosphonates. Serum β-CTX and osteocalcin levels were determined before and after the first and third months of teriparatide treatment and up to the fourth month of treatment with SR. RESULTS: We observed an initial significant increase in osteocalcin levels during the first month (165%, p = 0.01) followed by a peak of β-CTX (180%, p = 0.02) after the third month of treatment with teriparatide. An increase in these markers was also observed with SR: 49% in osteocalcin (p = 0.002) and 80% in β-CTX (p = 0.008). CONCLUSION: SR had a predominantly short-term bone-forming effect in postmenopausal women with osteoporosis previously treated with bisphosphonates in a lesser degree than with teriparatide.
Aspectos ultrassonográficos e hemodinâmicos da esquistossomose mansônica: avaliação pela ultrassonografia Doppler em áreas endêmicas
Authors: Azeredo Leticia Martins , Queiroz Leonardo Campos de , Marinho Carolina Coimbra , Espírito Santo Maria Cristina Carvalho do , Chammas Maria Cristina , Ruiz-Guevara Raiza , Prata Aluizio , Antunes Carlos Mauricio Figueiredo , Lambertucci José Roberto , Cerri Giovanni Guido
Published: May 2010

OBJETIVO: Este estudo de campo objetivou identificar as alterações ultrassonográficas e hemodinâmicas indicativas da morbidade da esquistossomose mansônica em áreas endêmicas. MATERIAIS E MÉTODOS: Foram examinados pela ultrassonografia Doppler 554 pacientes esquistossomóticos em três áreas com níveis distintos de endemicidade: baixa endemicidade (n = 109); média endemicidade (n = 255) e alta endemicidade (n = 190). Para o estudo ultrassonográfico foi utilizado o protocolo da Organização Mundial da Saúde (Niamey Working Group, 2000). Pelo Doppler foram avaliados: vasos portais, artérias hepática e esplênica, veias hepáticas e vasos colaterais. RESULTADOS: Houve correlação significativa entre a frequência das alterações ultrassonográficas e o nível de endemicidade das áreas, exceto a hipertrofia do lobo esquerdo. As veias hepáticas apresentaram padrão de fluxo alterado em 23,7% dos casos, alteração esta relacionada à presença e à intensidade de espessamento periportal. A artéria hepática não apresentou alterações nos parâmetros avaliados. Os vasos colaterais foram identificados apenas na área de alta endemicidade. A artéria esplênica apresentou alterações (aumento do calibre, da velocidade e do índice de resistência) mais frequentes na área de alta endemicidade, com diferença significativa entre os grupos. CONCLUSÃO: A ultrassonografia Doppler mostrou-se ferramenta auxiliar importante no estudo da morbidade relacionada à esquistossomose mansônica, contribuindo para definição mais precisa do perfil da doença nas áreas endêmicas.