bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lyapunov-Funktionen-basiertes FührungsfilterLyapunov Function based Set Point Generator
Authors: Buhl Michael , Lohmann Boris 
Published: October 2009

Zusammenfassung
Der Beitrag beschreibt ein Lyapunov-Funktionen-basiertes Führungsfilter für lineare Strecken mit Stellgrößenbegrenzung. Ziel des Filters ist es, die Abhängigkeit zwischen der zu stabilisierenden Ruhelage und der Größe des mit Lyapunov-Funktionen nachweisbaren Einzugsbereichs zu überwinden. Hierdurch kann erreicht werden, dass für alle Ruhelagen im System der gleiche Einzugsbereich nachgewiesen werden kann. Dieser umfasst die Vereinigungsmenge aller Abschätzungen ohne Führungsfilter.
Windenergienutzung mit schnell fliegenden Flugdrachen: eine Herausforderung für die Optimierung und RegelungWind Power via Fast Flying Kites: a Challenge for Optimization and Control
Authors: Diehl Moritz , Houska Boris 
Published: October 2009

Zusammenfassung
Der Beitrag beschreibt Optimierungsstudien für Windenergie erzeugende Flugdrachen, die mittels ihrer Leine periodisch an einem Generator ziehen und dabei sehr schnell quer zum Wind fliegen. Wir stellen den aktuellen Stand der Forschung beim Bau und Modellieren solcher Systeme dar und formulieren dann ein Optimalsteuerungsproblem mit periodischen Randbedingungen und freier Periodendauer. Die Zielfunktion ist die Durchschnittsleistung am Generator. Wir lösen dieses nichtlineare und instabile Optimalsteuerungsproblem numerisch mit Hilfe des direkten Mehrzielverfahrens. Das Resultat unserer Optimierungsrechnungen ist, dass etwa 5 MW Durchschnittsleistung mit einem 500 m2-Drachen bei 10 m/s Windgeschwindigkeit erzeugt werden können. Wenn zwei Drachen zu einem “tanzenden Drachenpaar” verbunden werden, kann die Effizienz um 40% pro Tragflügel gesteigert werden, da der Luftwiderstand der Leine deutlich verringert wird.
Identification of Novel Genes That Mediate Innate Immunity Using Inbred Mice
Authors: Yang Ivana V , Wade Claire M , Kang Hyun Min , Alper Scott , Rutledge Holly , Lackford Brad , Eskin Eleazar , Daly Mark J , Schwartz David A 
Published: October 2009

Abstract
Innate immunity is the first line of defense against microbial infections. Although polymorphisms in toll-like receptors (TLRs) and downstream signaling molecules (CD14, TLR2, TLR4, TLR5, and IRAK4) affect the innate immune response, these variants account for only a portion of the ability of the host to respond to bacteria, fungi, and viruses. To identify other genes involved in the innate immune response, we challenged 16 inbred murine strains with lipopolysaccharide (LPS) systemically and measured serum concentrations of pro-inflammatory cytokines IL-1β, IL-6, and TNFα, and the chemokine KC 6 hr post-treatment. Loci that segregate with strain phenotypes were identified by whole genome association (WGA) mapping of cytokine concentrations. Published gene expression profiles and quantitative trait loci (QTL) were then utilized to prioritize loci and genes that potentially regulate the host response to LPS. Sixteen loci were selected for further investigation by combining WGA analysis with previously published QTL for murine response to LPS or gram negative bacteria. Thirty-eight genes within these loci were then selected for further investigation on the basis of the significance of the identified locus, transcriptional response to LPS, and biological plausibility. RNA interference-mediated inhibition of 4 of 38 candidate genes was shown to block the production of IL-6 in J774A.1 macrophages. In summary, our analysis identified 4 genes that have not previously been implicated in innate immunity, namely, 1110058L19Rik, 4933415F23Rik, Fbxo9, and Ipo7. These genes could represent potential sepsis biomarkers or therapeutic targets that should be further investigated in human populations.
DLA-Based Strategies for Cloning Insertion Mutants: Cloning the gl4 Locus of Maize Using Mu Transposon Tagged Alleles
Authors: Liu Sanzhen , Dietrich Charles R , Schnable Patrick S 
Published: October 2009

Abstract
Digestion–ligation–amplification (DLA), a novel adaptor-mediated PCR-based method that uses a single-stranded oligo as the adaptor, was developed to overcome difficulties of amplifying unknown sequences flanking known DNA sequences in large genomes. DLA specifically overcomes the problems associated with existing methods for amplifying genomic sequences flanking Mu transposons, including high levels of nonspecific amplification. Two DLA-based strategies, MuClone and DLA-454, were developed to isolate Mu-tagged alleles. MuClone allows for the amplification of subsets of the numerous Mu transposons in the genome, using unique three-nucleotide tags at the 3′ ends of primers, simplifying the identification of flanking sequences that cosegregate with mutant phenotypes caused by Mu insertions. DLA-454, which combines DLA with 454 pyrosequencing, permits the efficient cloning of genes for which multiple independent insertion alleles are available without the need to develop segregating populations. The utility of each approach was validated by independently cloning the gl4 (glossy4) gene. Mutants of gl4 lack the normal accumulation of epicuticular waxes. The gl4 gene is a homolog of the Arabidopsis CUT1 gene, which encodes a condensing enzyme involved in the synthesis of very-long-chain fatty acids, which are precursors of epicuticular waxes.
Violence, Abuse, and Crime Exposure in a National Sample of Children and Youth
Authors: Finkelhor David , Turner Heather , Ormrod Richard , Hamby Sherry L. 
Published: October 2009

OBJECTIVE: The objective of this research was to obtain national estimates of exposure to the full spectrum of the childhood violence, abuse, and crime victimizations relevant to both clinical practice and public-policy approaches to the problem.METHODS: The study was based on a cross-sectional national telephone survey that involved a target sample of 4549 children aged 0 to 17 years.RESULTS: A clear majority (60.6%) of the children and youth in this nationally representative sample had experienced at least 1 direct or witnessed victimization in the previous year. Almost half (46.3%) had experienced a physical assault in the study year, 1 in 4 (24.6%) had experienced a property offense, 1 in 10 (10.2%) had experienced a form of child maltreatment, 6.1% had experienced a sexual victimization, and more than 1 in 4 (25.3%) had been a witness to violence or experienced another form of indirect victimization in the year, including 9.8% who had witnessed an intrafamily assault. One in 10 (10.2%) had experienced a victimization-related injury. More than one third (38.7%) had been exposed to 2 or more direct victimizations, 10.9% had 5 or more, and 2.4% had 10 or more during the study year.CONCLUSIONS: The scope and diversity of child exposure to victimization is not well recognized. Clinicians and researchers need to inquire about a larger spectrum of victimization types to identify multiply victimized children and tailor prevention and interventions to the full range of threats that children face.
Synchrony of Marine Fish Catches and Climate and Ocean Regime Shifts in the North Pacific Ocean
Authors: Noakes Donald J. , Beamish Richard J. 
Published: October 2009

Abstract
Catches of 19 marine fish species from the eastern and western portions of the North Pacific Ocean during 1970–2004 were examined to determine whether there was synchrony in their responses to the generally accepted climate regime shifts that occurred during that period. Catches for these species represented approximately 55% of the total fish catch in the North Pacific in the 1990s. Five distinct groups were apparent in the data, and each group exhibited a different response to the climate regime shifts of 1977, 1989, and 1998. Some species appeared to have responded only to the regime shift in 1977, others responded only to the shift in 1989, and a few species responded to both. The trends in the time series of catches for these five groups were not random, and shifts in catch generally coincided with regime shifts as identified by the Pacific Decadal Oscillation and other indices of climate change. Although this study examined the relationship of fisheries to trends in climate, there is an obvious linkage to the population dynamics of a particular species. Understanding how climate affects these linkages may help improve our ability to reliably forecast population and fishery trends in the future.
Dietary Segregation of Pelagic and Littoral Fish Assemblages in a Highly Modified Tidal Freshwater Estuary
Authors: Grimaldo Lenny F. , Stewart A. Robin , Kimmerer Wim 
Published: October 2009

Abstract
Estuarine food webs are highly variable and complex, making identification of their trophic pathways difficult. Energy for the food web of the San Francisco Estuary is thought to be based largely on in situ phytoplankton production, but little attention has been paid to littoral habitats, where other energy sources may be important. We analyzed the stomach contents of over 960 juvenile fishes and the stable carbon and nitrogen isotope ratios of these fishes and their potential food resources in pelagic and littoral habitats from the tidal freshwater area of the estuary. The mixing model IsoSource was used to examine energy sources important to consumers. Our results show evidence of two predominant food web pathways. Pelagic fishes and some littoral fishes showed strong dependence on a zooplankton–phytoplankton trophic pathway. However, the majority of fishes in littoral habitats had diets and carbon isotope ratios consistent with energy arising from submerged aquatic vegetation and epiphytic macroalgae. IsoSource revealed that the overall majority of nutrition of littoral fishes originated from consumption of grazer amphipods. Examining both stable isotopes and stomach contents allowed us to identify a food web with contributions to resident fishes that had been previously underestimated in the estuary. This study provides insight to how estuarine food webs have changed over the last few decades and highlights why the functions of habitats must be understood for effective restoration planning.
Estimation of Bottom Trawl Catch Efficiency for Two Demersal Fishes, the Atlantic Croaker and White Perch, in Chesapeake Bay
Authors: Hoffman Joel C. , Bonzek Chris F. , Latour Robert J. 
Published: October 2009

Abstract
The use of fisheries-independent trawl survey data to estimate fish abundance in shallow coastal systems can present challenges for producing reliable population estimates. We used hydroacoustic and trawl data to estimate the catch efficiency of a demersal trawl that is presently used in surveys to support stock assessments in Chesapeake Bay, USA. Specifically, we determined the efficiency of catching Atlantic croakers Micropogonias undulatus and white perch Morone americana, two of the most common species captured in the trawl survey. Monotypic hauls (&gt;90% by abundance) from 2003 to 2004 were used to estimate catch efficiency, defined as the ratio of the observed catch to the number of fish encountered by the trawl, which we estimated by deploying a scientific echosounder directly in front of the trawl net. The catch efficiency estimates ranged from 0.18 to 1.26 for Atlantic croakers (n = 29 tows) and from 0.11 to 0.60 for white perch (n = 7 tows). For Atlantic croakers, Spearman's rank correlation between the total and predicted catch was 0.53. A post hoc analysis of the Atlantic croaker efficiency estimates based on general linear modeling suggests that trawl efficiency is a function of fish behavior, gear geometry, and habitat. Efficiency declined with increasing fish density and increasing trawl width; to lesser extent, an increasing proportion of fines in the sea bed and decreasing depth were also associated with declines in efficiency. We conclude that because catch efficiency is variable, the trawl should be integrated with hydroacoustics to obtain improved population data.
A Genetic Assessment of Current Management Strategies for Spotted Seatrout in Texas
Authors: Anderson Joel D. , Karel William J. 
Published: October 2009

Abstract
The spotted seatrout Cynoscion nebulosus is one of the most intensively managed finfishes in the Gulf of Mexico, due primarily to its importance as a sport fish species throughout its range. As a result, genetic divergence and patterns of gene flow have previously been assessed among designated populations of spotted seatrout by using various types of genetic markers in an attempt to provide meaningful data for delineation of management units. However, genetic data can be influenced both by contemporary gene flow and historical demography, and these processes can often result in similar genetic signatures. In this study, a nested clade analysis (NCA) was used to disentangle the effects of historical and contemporary processes on the distribution of mitochondrial DNA sequence haplotypes of spotted seatrout in the western Gulf of Mexico. The NCA was coupled with traditional F-statistics and a Mantel matrix procedure to compare the results of multiple analytical frameworks. Overall, genetic divergence among populations was low but significant and was highest between populations that were far apart geographically. Correlation between genetic divergence and geographic distance was supported by a significant Mantel matrix correlation coefficient, as well as two nested clades, which had distributions that correlated significantly with latitude. All three statistical procedures suggest that the genetic structure of spotted seatrout in the western Gulf of Mexico can best be described by continuous change and isolation by distance rather than representing discrete populations. These results are compared to the results of several previous studies using alternative types of genetic data and analytical procedures and are also used to put current management strategies for spotted seatrout into a genetic context.
Decreases in Shark Catches and Mortality in the Hawaii-Based Longline Fishery as Documented by Fishery Observers
Authors: Walsh William A. , Bigelow Keith A. , Sender Karen L. 
Published: October 2009

Abstract
This article summarizes catch data for sharks collected by fishery observers during two periods (1995–2000 and 2004–2006) in the Hawaii-based pelagic longline fishery, which targets swordfish Xiphias gladius in the shallow-set sector and bigeye tuna Thunnus obesus in the deep-set sector. The blue shark Prionace glauca was the predominant shark species caught throughout the study period (84.5% of all sharks). Five other species (bigeye thresher Alopias superciliosus, oceanic whitetip shark Carcharhinus longimanus, shortfin mako Isurus oxyrinchus, silky shark C. falciformis, and crocodile shark Pseudocarcharias kamoharai) were relatively common (1.0–4.1%). Two major developments affected shark catches in this fishery during the study period. The first was the prohibition in 2000 of shark finning under most circumstances. The second development was that management measures were taken in 2000 and 2001 to protect sea turtles (leatherback sea turtles Dermochelys coriacea and loggerhead sea turtles Caretta caretta) and these measures included a closure of the shallow-set (swordfish-targeting) sector for more than 3 years. The closure caused decreases in shark catches because the shallow-set sector was typically characterized by high catch rates. The shallow-set sector was reopened in 2004. Comparisons of nominal catch per unit effort (number of sharks/1,000 hooks) revealed significant differences in catch rates between the two fishery sectors and the two periods. Blue shark and shortfin mako catch rates were significantly greater in the shallow-set sector than in the deep-set sector of the fishery, whereas the opposite was true for the deeper-dwelling bigeye threshers and crocodile sharks. Catch rates for the blue shark, oceanic whitetip shark, bigeye thresher, and crocodile shark were significantly lower in 2004–2006 than in 1995–2000. For the blue shark in particular, the combination of reduced catch rates, the finning ban, and an apparent capacity to resist the stress of capture on longline gear resulted in low (4%–5.7%) minimum mortality estimates. Therefore, we conclude that the Hawaii-based pelagic longline fishery has made substantial progress in reducing shark mortality.
Identification of Edwardsiella ictaluri and E. tarda by Species-Specific Polymerase Chain Reaction Targeted to the Upstream Region of the Fimbrial Gene
Authors: Sakai Takamitsu , Yuasa Kei , Sano Motohiko , Iida Takaji 
Published: October 2009

Abstract
Phylogenetic analysis of nine strains of Edwardsiella ictaluri and eight strains of E. tarda (six typical motile strains and two atypical nonmotile strains) isolated from diseased fish was performed using the upstream region of the fimbrial gene cluster. Strains of E. ictaluri and E. tarda were significantly clustered into separate groups. Moreover, atypical E. tarda strains were clustered into a different group from the other strains. Three polymerase chain reaction (PCR) primer sets for differential detection of E. ictaluri as well as typical and atypical E. tarda were developed from the respective characteristic sequences. Strains of E. ictaluri, typical E. tarda, and atypical E. tarda were specifically detected by PCR using each primer set. No amplifications were observed after the use of these three primer sets with 25 other bacterial species, including fish pathogens. In addition, the three primer sets were able to detect the DNA of each target species from fish kidney and liver artificially infected with E. ictaluri or E. tarda.
Genetic Characterization of Variation in Captive and Wild Woundfin
Authors: Chen Yongjiu , Conway Carole , Keeler-Foster Connie , Hamman Roger , Meismer Steve 
Published: October 2009

Abstract
The woundfin Plagopterus argentissimus is an endangered species that has been extirpated from most of its historic range in the Colorado River basin, now occurring only in the main-stem Virgin River. In 1987, refugial stocks were established at the Dexter National Fish Hatchery and Technology Center (Dexter) as a hedge against extinction. Offspring from the captive populations have been released in the Virgin River since 1993, by which time wild populations had markedly declined. This study was conducted to determine whether the stocks at Dexter have retained the character of the wild donor stocks as indicated by the distribution of genetic variation within and between stocks. The genetic composition of captive populations may diverge from that of wild donor populations, even over relatively short time periods, owing to founder effect, genetic drift, and selection for traits that are advantageous in captivity. Captive and wild stocks were surveyed, both spatially and temporally, using 10 microsatellite markers developed at Dexter. Microsatellite markers are considered selectively neutral, and this study measured genetic changes due to random evolutionary processes (given our approach, it would be unlikely to identify changes at nonneutral loci due to selection). Overall, the woundfin exhibited high levels of genetic variation for a freshwater species. The samples from the captive and wild woundfin populations had similar levels of heterozygosity, but generally the captive populations had fewer alleles. A comparison of composite samples of captive stocks and recent wild stocks yielded an FST value of 0.004. Although statistically significant, this level of genetic distance is typical of well-mixed or undifferentiated stocks. After 20 years of captive propagation, the stocks at Dexter do not appear to have been impacted by founder effect or genetic drift.
Factors Affecting Sea Lamprey Egg Survival
Authors: Smith Stephen J. , Marsden J. Ellen 
Published: October 2009

Abstract
Factors that affect recruitment of sea lampreys Petromyzon marinus are not well understood; for example, the majority (85%) of sea lamprey eggs are washed out of the nest, and the survival rate of these eggs is unknown. We examined the role of predation and substrate on egg survival in the laboratory and egg predation and dispersion of eggs outside the nest in the field. Substrate type did not influence the numbers of eggs consumed by predators, but the proportion of available eggs consumed was higher for crayfish Orconectes spp. (74%) and creek chub Semotilus atromaculatus (47%) than for white suckers Catostomus commersonii (9%) and logperch Percina caprodes (3%; F = 11.12, df = 3, P &lt; 0.0001). Survival of eggs incubated on silt (69.2%) and sand (50.8%) in the laboratory was significantly higher than survival on gravel (19.1%). Stream sampling indicated that sea lamprey egg density outside of nests on gravel was low (1.9 eggs/m2) compared with egg density in depositional areas (105.7 eggs/m2); eggs sampled outside the nest had near zero viability. In exclosure boxes seeded with sea lamprey eggs and deployed on gravel and silt for 7–10 d, egg retention was significantly greater on spawning gravel (31 ± 3%; mean ± SE) than on silt (6 ± 3%; P ≤ 0.0001); egg retention was affected by the presence of a 0.5-cm-mesh cover. Stream discharge appeared to increase egg loss from nests. We conclude that predation rates on sea lamprey eggs outside the nest are high and that substrate type alone has little impact on egg hatching success. Given the low retention of eggs in nests, egg mortality is probably a primary determinant of year-class strength. Production of sea lampreys outside the nest likely occurs under low stream discharge conditions from eggs deposited on spawning gravel.
Larval Fish Use of Dike Structures on a Navigable River
Authors: Niles Jonathan M. , Hartman Kyle J. 
Published: October 2009

Abstract
In rivers, velocity shelters are thought to serve as limiting factors in the retention and recruitment of young fish. Such shelters are formed in backwaters and tributaries; however, these areas are limited in many North American rivers. In response to this concern, several dike sites that serve as low-velocity zones were placed within the Kanawha River (West Virginia), a sixth-order tributary of the Ohio River. This study was conducted to evaluate whether the dike sites (finger and zipper dikes) provided velocity shelters that are used by larval fish. Larval fish were sampled during 2002 and 2003 using larval light traps. Larval fishes collected were typical of large river systems; Cyprinidae, Percidae, and Centrarchidae were the most abundant families. Results show that larval abundances peaked during late June in 2002 and early July in 2003. Overall taxonomic composition did not differ between dike sites and reference sites. Throughout the study, larval fish were captured at significantly higher rates (P &lt; 0.001) at dike sites than at high- and low-quality reference areas. Water velocities were significantly lower (P &lt; 0.001) at dike sites than at reference areas, suggesting that the greater larval fish use of dike sites may be attributed to reduced velocity provided by the structures. This study suggests that dike sites can serve as velocity shelters and retention areas for larval fish in navigationally impacted rivers.