bluuebunny/crossref_metadata_2025_split huggingface dataset:
Laboratory assessment of ammonia emission after soil application of treated and untreated manures
Authors: MONACO S. , SACCO D. , PELISSETTI S. , DINUCCIO E. , BALSARI P. , ROSTAMI M. , GRIGNANI C. 
Published: June 2011

SUMMARYAmmonia (NH3) volatilization from soil-applied manure not only causes environmental pollution but also reduces the fertilization value of the manure. Anaerobic digestion and solid/liquid separation alter the physical and chemical characteristics of slurry, which affect NH3 emissions after application. The present study measured potential laboratory NH3 losses from different manures, untreated pig slurry and the liquid fractions of each untreated and digested slurry, after their application to two different soil types. The experiment was carried out in dynamic chambers using a photoacoustic infrared gas analyser to determine the NH3 concentration in the air stream directly.The estimated values of nitrogen (N) emitted for surface-applied, untreated pig slurry were 0·26±0·064 mg per mg of applied total ammoniacal nitrogen (TAN). For the liquid fractions of pig slurry and digested pig slurry, results were 0·13±0·064 and 0·16±0·064 mg/mg, respectively. Initial NH3–N emission rates from surface-applied, untreated pig slurry were higher than those measured for either liquid fraction; in the case of the untreated pig slurry, half was emitted in the first 4·9 h of measurement. Silty-loam soil showed a higher N emission than loam soil with surface-applied slurries. This result was probably due to the higher infiltration rate of loam soil, even offsetting the effect of its high soil pH. Immediate manure incorporation into the soil was shown to reduce NH3 emissions by 82%. Results demonstrated that a method combining dynamic chambers with a photoacoustic gas analyser was as reliable as the widely used acid traps method. Moreover, direct measurement with the gas analyser permits an increasing temporal resolution that gave a high-quality description of the NH3 emission dynamic.
Visual memory as a potential cognitive endophenotype of attention deficit hyperactivity disorder
Authors: Shang C. Y. , Gau S. S. 
Published: June 2011

BackgroundExecutive functions have been proposed as endophenotypes for attention deficit hyperactivity disorder (ADHD); however, data regarding visual memory are lacking. We therefore assessed visual memory in adolescents with ADHD and their unaffected siblings compared with controls.MethodThe participants included 279 adolescents with ADHD, 108 unaffected siblings, and 173 unaffected school controls. They were assessed by using the visual memory tasks of the Cambridge Neuropsychological Test Automated Battery (CANTAB): Delayed Matching to Sample (DMS), Spatial Recognition Memory (SRM), Paired Associates Learning (PAL), and Pattern Recognition Memory (PRM).ResultsCompared with the controls, probands with ADHD had a significantly lower number of correct responses, a higher probability of an error following a correct response and following an error response in the DMS, and a lower percentage of correct responses in the SRM. Their unaffected siblings occupied an intermediate position between ADHD probands and controls in the probability of an error following a correct response and following an error response in the DMS, and in the percentage of correct responses in the SRM. In general, lower IQ and current use of and duration of treatment with methylphenidate were associated with more severe visual memory deficits.ConclusionsThe present results suggest that ADHD is associated with poorer visual memory function. Visual memory assessed by the DMS and SRM tasks in the CANTAB may be a useful endophenotype for ADHD.
The economic-institutional construction of regions: conceptualisation and operationalisation
Authors: POWERS KATHY , GOERTZ GARY 
Published: June 2011

AbstractThe international relations literature on regionalism, both in economic and security issues, has grown dramatically over the last 15 years. One of the ongoing issues discussed in most articles and books is the conceptualisation of ‘region’. Instead of thinking about regions using notions of interdependence and interaction we take a social constructivist approach, whereby states themselves define regions via the construction of regional economic institutions (REI). We explore how a conceptualisation of region based on REIs contrasts with various related concepts such as regional system, and regional IGO. Empirically, we show that most all countries belong to at least one important regional economic institution, REI, (for example, EU, Mercosur, ASEAN, etc). In short, the world is dividing itself into regions by the creation of regional economic institutions. We contrast our economic-institutional approach to regions with Buzan and Wæver's ‘regional security complexes’ which is based on security dependence. There are interesting agreements and disagreements between their approach and our economic-institutional approach to defining regions. It is perhaps not surprising that many REIs have taken on security roles, which we briefly show by looking at military alliances embedded in REIs. This suggests that policymakers are creating regions through institutional innovations that link economic and security issues.
Why do civil wars occur? Another look at the theoretical dichotomy of opportunity versus grievance
Authors: TAYDAS ZEYNEP , ENIA JASON , JAMES PATRICK 
Published: June 2011

AbstractThe purpose of this article is to review major theoretical arguments with regard to the causes of civil war and identify problems associated with the conceptual juxtaposition of opportunity versus grievance that predominates in the field. While they are critical aspects of conflict processes, perception of opportunity and grievance as two mutually competing explanations or separate categories ultimately can limit, rather than facilitate, our understanding of civil conflicts. For example, we show that not all motives can be designated easily as deriving from one or the other. In addition, the existing dichotomous framework masks other important questions about the way that collective action is achieved in some circumstances and not others or the way that some factors seem to generate grievances at one stage, perhaps, but then an opportunity at another orvice versa. Thus the priority should be to develop an integrated, comprehensive approach that can account for fundamental aspects of complex conflict processes. We conclude by providing suggestions for future research on civil conflict.
Effect of chirping on the intensity profile and growth rate of modulation instability of a laser pulse propagating in plasma
Authors: Mishra Rohit K. , Jha Pallavi 
Published: June 2011

AbstractThis paper deals with the analytical study of the effect of chirping of a laser pulse on its intensity profile, as it propagates in plasma. Considering a matched laser beam, graphical analysis of the intensity distribution across the chirped laser pulse and growth of modulation instability has been presented. Further, considering finite pulse effects to be a perturbation, the growth rate of modulation instability of the chirped laser pulse is evaluated and compared with that obtained due to an unchirped pulse.
Stability properties of the electron return current for intense ion beam propagation through background plasma
Authors: Khudik V.N. , Startsev E.A. , Davidson R.C. 
Published: June 2011

AbstractWhen an intense ion beam propagates through a dense background plasma, its current is partially neutralized by the electron plasma return current. Due to the non-uniformity of the background plasma electrons longitudinal velocity profile ${\bar v}$(r), the flow can be unstable. The instability is similar to the Kelvin-Helmholz instability for the non-uniform flow of an incompressible neutral fluid, with the electrostatic potential playing the role of pressure. For the case of electron return current flow, the significant new feature is the presence of the partially self-neutralized magnetic field of the ion beam, which significantly affects the evolution of small-amplitude excitations. In this paper the stability properties of the flow of electrons making up the plasma return current is investigated using the macroscopic cold-fluid-Maxwell equations. It is shown that this flow may become unstable, but the instability growth rates are exponentially small. This unstable body mode is qualitatively different from previously studied surface-mode excitations of the electron plasma return current for an intense ion beam with a sharp radial boundary, which is found to be stable due to the stabilizing influence of the partially neutralized magnetic field of the ion beam.
TELESCOPIC LINKAGES AND A TOPOLOGICAL APPROACH TO PHASE TRANSITIONS
Authors: FARBER MICHAEL , FROMM VIKTOR 
Published: June 2011

AbstractA topological approach to the theory of equilibrium phase transitions in statistical physics is based on the topological hypothesis, which claims that phase transitions are due to changes of the topology of suitable submanifolds in the configuration space. In this paper we examine in detail the antiferromagnetic mean-field XY model and study the topology of the subenergy manifolds. The latter can be interpreted mechanically as the configuration space of a linkage with one telescopic leg. We use methods of Morse theory to describe explicitly the Betti numbers of this configuration space. We apply these results to the antiferromagnetic mean-field XY model and compute the exponential growth rate of the total Betti number. Previous authors studied the Euler characteristic rather than the total Betti number. We show that in the presence of an external magnetic field the model undergoes a single ‘total Betti number phase transition’.
The Social Science of Democracy?
Authors: Craiutu Aurelian 
Published: June 2011

Alexis de Tocqueville, the First Social Scientist. By Jon Elster. New York: Cambridge University Press, 2009. 212p. $80.00 cloth, $22.99 paper.Alexis de Tocqueville is surely one of the most widely cited, discussed, and celebrated political theorists in the world. Jon Elster's book,Alexis de Tocqueville: the First Social Scientistproceeds from a provocative premise: that Tocqueville's major works were lacking in “system” and were “hugely incoherent,” and that Tocqeuville himself “was not a major political thinker” (xi). Elster argues that instead Tocqueville ought to be viewed as a penetrating historical sociologist and an exemplary social scientist who might well be considered the first true social scientist. Elster's argument is important for at least two reasons: first, because it offers a striking and challenging reading of Tocqueville; and second, because it expands on Elster's own contributions in the philosophy of social science, and develops interesting understandings of “causal mechanisms,” methodological individualism, and social explanation more generally. As Elster writes in his Introduction, “the main task of this book is to argue for the relevance of Tocqueville for social science in the twenty-first century (p. 5).” The purpose of this Perspectives symposium is to assess Elster's argument in broad terms. What are the strengths and limits of Elster's reading of Tocqueville? How ought we to assess Elster's understanding of Tocqueville's deficiencies as a “political theorist?” What is the relevance of Tocqueville for contemporary social science? And, most importantly, what are the challenges and possible trajectories facing social science in the twenty-first century, and to what extent does Elster's essay point us in the right direction?—Jeffrey C. Isaac, Editor
The Social Science of Democracy?
Authors: Gerring John 
Published: June 2011

Alexis de Tocqueville, the First Social Scientist. By Jon Elster. New York: Cambridge University Press, 2009. 212p. $80.00 cloth, $22.99 paper.Alexis de Tocqueville is surely one of the most widely cited, discussed, and celebrated political theorists in the world. Jon Elster's book,Alexis de Tocqueville: the First Social Scientistproceeds from a provocative premise: that Tocqueville's major works were lacking in “system” and were “hugely incoherent,” and that Tocqeuville himself “was not a major political thinker” (xi). Elster argues that instead Tocqueville ought to be viewed as a penetrating historical sociologist and an exemplary social scientist who might well be considered the first true social scientist. Elster's argument is important for at least two reasons: first, because it offers a striking and challenging reading of Tocqueville; and second, because it expands on Elster's own contributions in the philosophy of social science, and develops interesting understandings of “causal mechanisms,” methodological individualism, and social explanation more generally. As Elster writes in his Introduction, “the main task of this book is to argue for the relevance of Tocqueville for social science in the twenty-first century (p. 5).” The purpose of this Perspectives symposium is to assess Elster's argument in broad terms. What are the strengths and limits of Elster's reading of Tocqueville? How ought we to assess Elster's understanding of Tocqueville's deficiencies as a “political theorist?” What is the relevance of Tocqueville for contemporary social science? And, most importantly, what are the challenges and possible trajectories facing social science in the twenty-first century, and to what extent does Elster's essay point us in the right direction?—Jeffrey C. Isaac, Editor
Increasing incidence of thyroid cancer in shanghai, China, 1983-2007
Authors: Wang Youxin , Wang Wei 
Published: June 2011

AbstractIncreasing incidences of thyroid cancer were observed in some countries, like USA, UK, France, etc. Jointpoint regression was used to analyze the incidence of thyroid cancer in Shanghai, China, from 1983 to 2007. The results showed there were both two distinct slopes, in males representing a significant APC of 2.6% from 1983 to 2000 (P<0.001), followed by a sharply increased APC of 14.4% (P <0 .001), and in females representing a significant APC of 4.9% from 1983 to 2003 (P<0.001), followed by a sharply increased APC of 19.9% (P =0 .001). Incidence of thyroid cancer increased 5 to 8 years after the supplement of iodine, for males and females respectively, suggesting that either the developed screening techniques or supplement of iodine might contribute to this accelerated increase in incidence of thyroid cancer. The predicated future burdens indicated that thyroid cancer is never an unusual cancer, either in the present or in the future.
Using a Genetic Mixture Model to Study Phenotypic Traits: Differential Fecundity among Yukon River Chinook Salmon
Authors: Bromaghin Jeffrey F. , Evenson Danielle F. , McLain Thomas H. , Flannery Blair G. 
Published: June 2011

AbstractFecundity is a vital population characteristic that is directly linked to the productivity of fish populations. Historic data from Yukon River (Alaska) Chinook salmonOncorhynchus tshawytschasuggest that length‐adjusted fecundity differs among populations within the drainage and either is temporally variable or has declined. Yukon River Chinook salmon have been harvested in large‐mesh gill‐net fisheries for decades, and a decline in fecundity was considered a potential evolutionary response to size‐selective exploitation. The implications for fishery conservation and management led us to further investigate the fecundity of Yukon River Chinook salmon populations. Matched observations of fecundity, length, and genotype were collected from a sample of adult females captured from the multipopulation spawning migration near the mouth of the Yukon River in 2008. These data were modeled by using a new mixture model, which was developed by extending the conditional maximum likelihood mixture model that is commonly used to estimate the composition of multipopulation mixtures based on genetic data. The new model facilitates maximum likelihood estimation of stock‐specific fecundity parameters without first using individual assignment to a putative population of origin, thus avoiding potential biases caused by assignment error. The hypothesis that fecundity of Chinook salmon has declined was not supported; this result implies that fecundity exhibits high interannual variability. However, length‐adjusted fecundity estimates decreased as migratory distance increased, and fecundity was more strongly dependent on fish size for populations spawning in the middle and upper portions of the drainage. These findings provide insights into potential constraints on reproductive investment imposed by long migrations and warrant consideration in fisheries management and conservation. The new mixture model extends the utility of genetic markers to new applications and can be easily adapted to study any observable trait or condition that may vary among populations.
Observation of Atlantic Sturgeon Predation by a Flathead Catfish
Authors: Flowers H. Jared , Bonvechio Timothy F. , Peterson Douglas L. 
Published: June 2011

AbstractSturgeons (family Acipenseridae) are a highly threatened taxon worldwide; populations have declined for several reasons, including overfishing and habitat modification. It has been suggested that the widely introduced, highly piscivorous, flathead catfish Pylodictis olivaris is responsible for the decline of certain sturgeon populations in North America. Here we present the first field observation of flathead catfish predation on a sturgeon of any species, an Atlantic sturgeon Acipenser oxyrinchus in the Satilla River, Georgia. Our finding demonstrates a potential impact of flathead catfish predation on sturgeon populations; however, more research is needed to describe the full magnitude of such effects on sturgeon populations.
Temporal Variation in Prevalence of Viral Hemorrhagic Septicemia Virus Type IVb among Upper St. Lawrence River Smallmouth Bass
Authors: Eckerlin Geofrey E. , Farrell John M. , Casey Rufina N. , Hope Kristine M. , Groocock Geoffrey H. , Bowser Paul R. , Casey James 
Published: June 2011

AbstractWe investigated a newly introduced pathogen in a wild population of smallmouth bass Micropterus dolomieu in the St. Lawrence River to illuminate unknown temporal and demographic prevalence patterns. We used real‐time quantitative reverse‐transcription polymerase chain reaction to assess viral hemorrhagic septicemia virus (VHSV) genotype IVb (VHSV‐IVb) viral N‐gene levels. Our objectives were to characterize the distribution and abundance of this newly introduced pathogen within a naïve population of economically valuable sport fish through an annual cycle. We also sought to describe VHSV‐IVb levels across demographic groups (males and females; adults and subadults). Strong temporal variation in prevalence of VHSV‐IVb was evident through the annual cycle; peaks in prevalence corresponded to the smallmouth bass spawning period and a temperature range of 10–14°C. No difference in VHSV‐IVb prevalence between male and female smallmouth bass was detected. However, a markedly higher prevalence was observed in subadult fish than in adult fish. Owing to the observed temporal patterns in prevalence, surveillance programs for VHSV‐IVb in smallmouth bass should concentrate effort on springtime sampling and should include subadult fish.
Fish Entrainment Rates through Towboat Propellers in the Upper Mississippi and Illinois Rivers
Authors: Killgore K. Jack , Miranda L. E. , Murphy Catherine E. , Wolff Douglas M. , Hoover Jan Jeffrey , Keevin Thomas M. , Maynord Steven T. , Cornish Mark A. 
Published: June 2011

AbstractA specially designed net was used to study fish entrainment and injury through towboat propellers in 13 pools of the Upper Mississippi and Illinois rivers. The net was attached to the stern of a 48.8‐m‐long towboat with twin propellers (in Kort propulsion nozzles), and sampling typically took place while the towboat pushed 15 loaded barges upstream at a time. In total, 254 entrainment samples over 894 km of the 13 study pools were collected. The sampling efforts produced 16,005 fish representing 15 families and at least 44 species; fish ranged in total length from 3 to 123 cm, but only 12.5‐cm or longer fish were analyzed because smaller fish could escape through the mesh of the trawl. Clupeidae (68% of total catch) and Sciaenidae (21%) were the dominant families. We detected no effects of towboat operation variables (speed and engine [i.e., propeller] revolutions per minute [RPM]) on entrainment rate (i.e., fish/km), but entrainment rate showed a wedge‐shaped distribution relative to hydraulic and geomorphic characteristics of the channel. Entrainment rate was low (<1 fish/km) in wide sections of the river, deep water, and swift current (or time periods characterized by faster flow); however, entrainment in narrow sections with shallow, slow water was highly variable and occasionally reached high levels (>30 fish/km). Although total entrainment rate was not related to engine RPM, the probability of being struck by a propeller increased with fish length and engine RPM. Limits on engine RPM in narrow, shallow, and sluggish reaches could reduce entrainment impact, particularly for large‐bodied fish.
Effectiveness and Trade‐Offs Associated with Hydraulic Egg Collections from Natural Salmon and Steelhead Redds for Conservation Hatchery Programs
Authors: Berejikian Barry A. , Gable Joshua T. , Vidergar Dmitri T. 
Published: June 2011

AbstractMaintaining a large genetically effective number of breeders (Nb) in supplemented salmon populations is considered vital to their long‐term sustainability, yet may be difficult to consistently achieve in practice, especially in conservation hatchery programs that require small numbers of eggs for captive rearing. We evaluated efforts to hydraulically collect eggs from naturally produced redds, as implemented by conservation hatchery programs for Endangered Species Act listed populations of Snake River Chinook salmon Oncorhynchus tshawytscha and Hood Canal steelhead O. mykiss; we then compared the estimated Nb represented in the hydraulically collected captive populations with the Nb obtained by the more conventional approach (i.e., adult collection and artificial spawning). Egg collection goals in the steelhead and Chinook salmon conservation hatchery programs were met in most cases and were never exceeded. The embryo viability and egg‐to‐fry survival consistently exceeded 90% and were no less than would be expected through artificial spawning. Demographic estimates suggested that a greater Nb in the captive population would be obtained by hydraulic redd sampling than by artificial spawning of captured adults to produce a specific, limited number of eggs. Hydraulic redd sampling allows sexual selection to occur naturally on the spawning grounds and does not require barrier weirs, handling of adults, or the removal of a female's entire fecundity from natural production. The high rate of survival to emergence for hydraulically collected eggs (>95%) suggests that eggs are not damaged by the collection process, but the fate of uncollected eggs that are disturbed during the process is unknown. Hydraulic redd sampling requires fairly frequent redd surveys to time collections at the proper stage of embryonic development, and access to some redds in remote areas can be difficult. Hydraulic sampling of eyed eggs appears to have largely accomplished the goals of these small‐ to moderately‐sized conservation hatchery programs.