bluuebunny/crossref_metadata_2025 huggingface dataset:
The Shiraz model: a tool for incorporating anthropogenic effects and fish–habitat relationships in conservation planning
Authors: Scheuerell Mark D , Hilborn Ray , Ruckelshaus Mary H , Bartz Krista K , Lagueux Kerry M , Haas Andrew D , Rawson Kit
Published: July 2006

Current efforts to conserve Pacific salmon (Oncorhynchus spp.) rely on a variety of information sources, including empirical observations, expert opinion, and models. Here we outline a framework for incorporating detailed information on density-dependent population growth, habitat attributes, hatchery operations, and harvest management into conservation planning in a time-varying, spatially explicit manner. We rely on a multistage Beverton–Holt model to describe the production of salmon from one life stage to the next. We use information from the literature to construct relationships between the physical environment and the necessary productivity and capacity parameters for the model. As an example of how policy makers can use the model in recovery planning, we applied the model to a threatened population of Chinook salmon (Oncorhynchus tshawytscha) in the Snohomish River basin in Puget Sound, Washington, USA. By incorporating additional data on hatchery operations and harvest management for Snohomish River basin stocks, we show how proposed actions to improve physical habitat throughout the basin translate into projected improvements in four important population attributes: abundance, productivity, spatial structure, and life-history diversity. We also describe how to adapt the model to a variety of other management applications.
Using thalweg profiling to assess and monitor juvenile salmon (Oncorhynchus spp.) habitat in small streams
Authors: Mossop Brent , Bradford Michael J
Published: July 2006

Thalweg profiles are longitudinal profiles of the streambed elevation measured along the deepest portion of the stream. This technique has recently been advocated as a tool to assess and monitor fish habitat in streams because metrics calculated from thalweg profiles can provide useful information on habitat quality, and measurements are both repeatable and independent of stream flow. Relations between thalweg metrics and land use have also been documented. However, a relation between fish abundance and thalweg metrics has not been established. To develop this relation, we surveyed thalweg profiles and sampled juvenile Chinook salmon (Oncorhynchus tshawytscha) density in 14 reaches of small tributary streams of the upper Yukon River. Chinook salmon density was correlated with three thalweg metrics. Two of these metrics  length in residual pool and mean maximum residual pool depth  provided useful measures of pool extent and quality and useful information on Chinook salmon habitat. Thalweg metrics differed between these undisturbed streams and reaches in streams affected by placer gold mining. These results suggest that thalweg profiling provides a useful tool to assess and monitor fish habitat in small streams.
Characterizing flat-top laser beams using standard beam parameters
Authors: Saghafi S , Withford M J , Ghoranneviss Z
Published: July 2006

We examine the correspondence between various models describing flat-top laser beam profiles using two standard parameters; namely, the M2 factor and the kurtosis parameter. Numerical expressions for M2, based on the second moment of the beam irradiance distribution in the near and far fields and for the kurtosis parameter, k, based on the fourth moment at the near field, are obtained. Plots of k in the near field versus M2 demonstrate the similarities between the different analytical models used to describe flat-top profiles. Using the Padé approximation, a relationship between k and M2, a new reference formula, is derived that predicts the values of M2 to within less than a percent for these flattened beams. This method is then extended to define numerical expressions relating the beam parameters (i.e., M2 and k) and the parameters describing the beam characteristic in each analytical model (model parameters). The results obtained using the Padé method are used to describe the output beam profiles for a high power copper vapour laser fitted with an unstable resonator.PACS Nos.: 42.55.–f, 42.55.Lt, 42.60.–v
Distorted waves with exact nonlocal exchange: A canonical function approach
Authors: Fakhreddine K , Tweed R J , Vien G Nguyen , Tannous C , Langlois J , Robaux O
Published: July 2006

The Canonical Function Method (CFM) is developed and applied, for the first time, to the distorted wave problem with exact nonlocal exchange. In electron impact ionization of hydrogenic systems, the latter originates from the Pauli exclusion principle that leads, in the Hartree–Fock approximation, to a radial Schrodinger equation of an integro-differential type. The application of the CFM with static and polarization potentials allows us to obtain the phaseshifts and scattering lengths in the s-wave singlet and triplet states at high (≥5 eV) and low energies (≤0.1 eV). The results are compared with those obtained by other methods based on exact exchange, local equivalent-exchange potentials and recently developed spectral integral equation methods (S-IEM). The accuracy, stability, and speed of convergence of the CFM are analysed and compare favorably with other methods including the highly accurate S-IEM. At very low energies, the CFM is superior to all known methods.PACS Nos.: 34.00.00, 34.50.–s, 03.65.–w, 02.60.Nm, 02.60.–x
ε-Expansion for nonplanar six-propagators double boxes
Authors: Suzuki A T , Schmidt A GM
Published: July 2006

We present calculations for a nonplanar double box with four massless, massive external, and internal legs propagators. The results are expressed for arbitrary exponents of propagators and dimension in terms of Lauricella's hypergeometric functions of three variables and hypergeometric-like multiple series. PACS Nos.: 11.15.Bt, 12.38.Bx
Effect of filter–separators on the clogging of leachate collection systems
Authors: McIsaac Reagan , Rowe R Kerry
Published: July 2006

This paper reports the results obtained after 6 years operation of nine mesocosm experiments that simulate the 50 cm of the drainage layer closest to the leachate collection pipe in a landfill. Five different design configurations were examined involving a 300 mm thick layer of coarse (38 mm) gravel. The designs differed in terms of the presence, nature, and location of a filter–separator layer either at the waste–gravel interface or partway through the gravel. A nonwoven geotextile filter–separator (GTF/S) is shown to reduce clogging of the gravel relative to the no filter–separator or woven GTF/S designs. Some clogging of the geotextiles is reported, with reductions in geotextile hydraulic conductivity of 23% for the woven GTF/S, 74%–89% for the nonwoven GTF/S, and 75%–94% for the nonwoven geotextile partway through the gravel. The clogged nonwoven geotextile filter–separator maintained a higher hydraulic conductivity than the extracted woven geotextile. Of the designs with a filter–separator between the waste and gravel, the granular filter–separator most effectively reduced clogging of the gravel but at the expense of leachate mounding above the sand once the sand layer clogs. The design with a nonwoven geotextile partway through the gravel (GTMF) provides better protection of the underlying gravel from clogging than other designs involving a geotextile.Key words: landfill, waste, leachate, clogging, biofilm, geotextile.
Solubility prediction of anthracene in nonaqueous solvent mixtures using a combination of Jouyban-Acree and Abraham models
Authors: Jouyban Abolghasem , Khoubnasabjafari Maryam , Acree, Jr. William E
Published: July 2006

The applicability of previously developed quantitative structure-property relationships was extended to predict the solubility of anthracene in nonaqueous binary and ternary solvent mixtures. The accuracy of the proposed methods was evaluated using 81 solubility data sets collected from the literature. The individual and mean percentage deviation (IPD and MPD) of experimental and computed solubilities were calculated as accuracy criteria. The computations were carried out using experimental and predicted mole fraction solubility of anthracene in monosolvent systems for binary and ternary solvent systems. The overall MPD of solubility prediction using experimental values in monosolvents varied from 5.2% to 4.2% and from 16.5% to 10.7% for binary and ternary solvents, using water to solvent and gas to solvent solvational parameters, respectively. The IPD distribution was better for the gas to solvent model. The corresponding ranges for the predicted solubility of anthracene in monosolvents were 47.9% to 28.1% and 23.9% to 22.5% for binary and ternary solvents, respectively, and IPD distribution was more favourable for the gas to solvent model. In general, the models derived from gas to solvent coefficients provided more accurate predictions and are recommended for practical applications.Key words: solubility, prediction, cosolvency, anthracene, Abraham model, Jouyban-Acree model.
Synthesis, characterization, and the molecular structures of two new kinds of stilbene
Authors: Liu Yan-Hong , Zhang Tong-Lai , Zhang Jian-Guo , Yang Li , Guo Jin-Yu , Yu Wei , Wu Rui-Feng , Yu Kai-Bei
Published: July 2006

We report in this study the synthesis, crystal culture, and single-crystal X-ray crystallography of two new kinds of double stilbene, which were readily prepared from trinitro-p-xylene and p-tolualdehyde in the presence of piperidine. We found that these triclinic crystals belong to the space group P-1. These compounds were also investigated using FT-IR, 1H NMR, 13C NMR, and MS spectroscopy techniques. The thermal decomposition processes of the compounds were tested by DSC and TG-DTG at a heating rate of 10  C/min. These results indicate that the compounds have high heat-resistant stability.Key words: polynitrostilbene, molecular structure, thermal decomposition.
The volatilities and conductivities of ionic liquids — GC–MS methodology and preliminary studies of acetic acid – base systems
Authors: Treble Ronald G , Johnson Keith E , Tosh Evangeline
Published: July 2006

Gas chromatography – mass spectrometry studies of the headspaces above the binary systems pyridine (bp 115 °C) – acetic acid (bp 116 °C), 1-methylimidazole (bp 198 °C) – acetic acid, and triethylamine (bp 89 °C) – acetic acid show both components in the first case, acetic acid only in the second, and triethylamine only in the third. Negative deviations from Raoult's law are confirmed and proton transfer is evidenced by the downfield shift of the acidic proton as the addition of base proceeds. Specific conductances >2 mS cm–1 are found over wide composition ranges for all three systems with values >8 mS cm–1 at high (>2) mole ratios of acetic acid, suggesting the formation of acetatohydrogenate ionic liquids.Key words: GC–MS, air, vapor pressure, conductivity, ionic liquids, acetic acid.
Selecting models for capturing tree-size effects on growthresource relationships
Authors: MacFarlane David W , Kobe Richard K
Published: July 2006

Subject trees included in growth analyses often vary in their initial size, possibly obscuring the effects of growth factors. We compare methods for incorporating size effects into growth models. For four different tree species, red maple (Acer rubrum L.), sugar maple (Acer saccharum Marsh.), American beech (Fagus grandifolia Ehrh.), and red oak (Quercus rubra L.), we compared models of radial growth rate of saplings as a function of light, water, and nitrogen availability that (i) ignored size effects on absolute growthresource relationships, (ii) related absolute growth rate (AGR) to size and resource availability, (iii) related relative growth rate (RGR) to resource availability, and (iv) related RGR to tree size and resource availability. Size effects explained 13%14% of variation in growth rates, and failure to account for these effects resulted in a substantial size bias in growth prediction. Overall, AGR-based models that included size as a predictor variable provided the best predictions and clearest interpretation of growthresource relationships across all growth model types and species examined. Modeling RGR without including size effects resulted in residual size bias. Including size as a predictor of RGR yielded nearly equivalent results to using size to predict AGR. We suggest that investigators evaluate both AGR- and RGR-based approaches and determine which is most appropriate for their study.
Protists in soil ecology and forest nutrient cycling
Authors: Adl M S , Gupta VV SR
Published: July 2006

Recent progress in protistology has shown that these organisms (protists) are far more diverse than traditionally assumed by soil ecologists. Most studies have grouped these into motility groups, as amoebae, flagellates, and ciliates. Unfortunately, these do not represent functionally useful groups and do not have any ecological relevance to food web processes and community structure. Typically, abundance values have relied on the most probable number estimate based on bacterivore cultures. In fact, there are many functional groups of protists besides the bacterivores. These other functional groups are very much part of the forest soil decomposition food web, but they remain unaccounted for in models. Modelling studies have shown repeatedly that protozoan bacterivores are responsible for much of the nutrient turnover and flux through the soil food web, as they are in the aquatic microbial loop. The contribution of other protist functional groups to this nutrient cycling remains to be quantified. To this end, new sampling strategies are required, and functional diversity needs to be considered in future studies. We consider both temporal and spatial stratification as contributing factors, to explain the apparent redundancy of function. Finally, drawing on data from agricultural fields, we consider new ideas on rates of recovery after disturbance.
Scale-dependent environmental controls over species composition in Alaskan black spruce communities
Authors: Hollingsworth T N , Walker M D , Chapin III F S , Parsons A L
Published: July 2006

The boreal forest is the second largest terrestrial biome, and the black spruce (Picea mariana (Mill.) BSP) forest type occupies a large extent of boreal North America. Black spruce communities occur in a variety of environmental conditions and are especially important in the context of climate change because of underlain permafrost in much of the northern black spruce forests, as well as their adaptation to fire disturbance. We used a classification and ordination approach to describe and name Alaskan black spruce communities and relate them to key environmental variables. We analyzed the relationship of species richness with topographic position and with soil pH using both univariate and multivariate analyses of variance. We also explored the variability in structural, physical, and soil characteristics. We described three black spruce community types and five subtypes based purely on floristic composition. Paludification and topography were the most important gradients explaining species composition for the Fairbanks region (61% variance explained). However, at the scale of interior Alaska, pH, drainage, and productivity were the strongest environmental gradients (81% variance explained). We conclude that species composition of mature black spruce forests in interior Alaska results from the complex interaction of landscape and fire history, soil pH, paludification, permafrost, and topographic position.
Dynamics of regeneration gaps following harvest of aspen stands
Authors: MacIsaac Daniel A , Comeau Philip G , Macdonald S Ellen
Published: July 2006

This study assessed the dynamics of gap development in postharvest regeneration in five stands in northwestern Alberta dominated by trembling aspen (Populus tremuloides Michx.). The pattern of gap development over time was determined from analysis of air photographs taken preharvest and 1, 4, 10, and 12 years postharvest. The area of each stand covered by gaps increased after harvest because of the addition of harvest-related gaps over and above those that had been present prior to harvest. The blocks we studied had a combined gap area of up to 29% of stand area 12 years postharvest. We measured regeneration characteristics, microsite, soil, light, and browse conditions in 30 aspen regeneration gaps (gaps in regeneration that were not gaps preharvest and were not due to obvious harvest-related disturbance) 14 years following harvest. Although deciduous trees within postharvest regeneration gaps were the same age as those outside (i.e., in a fully stocked matrix of newly established even-aged aspen stems), they were often suppressed, with significantly lower density and growth. Within the 14-year-old postharvest regenerating aspen stands, aspen height varied from 1 to 11 m; this substantial variability appeared to be largely due to the influence of browsing. There was little evidence of ongoing regeneration within postharvest regeneration gaps, indicating that these gaps will probably persist over time. This may impact future deciduous stocking and volume. It is unknown what may have initiated the formation of these gaps, although results suggest that they are not due to edaphic conditions or disease in the preharvest stands. There is evidence that bluejoint (Calamagrostis canadensis (Michx.) Beauv.) cover and browsing are important factors in the maintenance of postharvest regeneration gaps. The spatial heterogeneity resulting from gaps could be advantageous, however, either as part of ecosystem-based management emulating natural disturbance or as a template for mixedwood management, where white spruce (Picea glauca (Moench) Voss) are established in gaps.
TESTING THE STRUCTURE OF THE SCALAR MESON $K_0^*(1430)$ IN $\tau\to K_0^*(1430)\nu$ DECAY
Authors: YANG MAO-ZHI
Published: July 2006

The decay constant of [Formula: see text] is the key quantity to determine the production rate of [Formula: see text] in τ decays. By assuming [Formula: see text] is the lowest scalar bound state of [Formula: see text], the decay constant can be calculated reliably in QCD sum rule. Then the decay branching ratio of [Formula: see text] is predicted to be about (7.9±3.1)×10-5. If this branching ratio can be measured by experiment, it should be helpful to make clear the structure of [Formula: see text].
THE CHIRAL QUARK CONDENSATE AND THE BAG CONSTANT WITH FINITE CHEMICAL POTENTIAL
Authors: ZONG HONG-SHI , PING JIA-LUN , SUN WEI-MIN , WANG FAN , CHANG CHAO-HSI
Published: July 2006

A method for obtaining the low chemical potential dependence of the dressed quark propagator from an effective quark–quark interaction model is developed. From this the chemical potential dependence of the "effective" two quark condensate and the bag constant is evaluated. A comparison with previous results is given.
EXCITED HADRONS AS A SIGNAL FOR QUARK–GLUON PLASMA FORMATION
Authors: LAYEK BISWANATH , SRIVASTAVA AJIT M. , SANYAL SOMA
Published: July 2006

At the quark–hadron transition, when quarks get confined to hadrons, certain orbitally excited states, namely those which have excitation energies above the respective L = 0 states of the same order as the transition temperature Tc, may form easily because of thermal velocities of quarks at the transition temperature. We propose that the ratio of multiplicities of such excited states to the respective L = 0 states can serve as an almost model independent signal for the quark–gluon plasma (QGP) formation in relativistic heavy-ion collisions. For example, the ratio R* of multiplicities of [Formula: see text] and [Formula: see text] when plotted with respect to the center-of-mass energy of the collision [Formula: see text] (or vs. centrality/number of participants), should show a jump at the value of [Formula: see text] beyond which the QGP formation occurs. This should happen irrespective of the shape of the overall plot of R* vs. [Formula: see text]. Recent data from RHIC on Λ*/Λ vs. N part for large values of N part may be indicative of such a behavior, though there are large error bars. We give a list of several other such candidate hadronic states.
STRUCTURAL TRANSFORMATION IN PbS AND HgS NANOCRYSTALS UNDER HIGH PRESSURE
Authors: FRENY JOY K. M. , VICTOR JAYA N. , ZHU JUN-JIE
Published: July 2006

The phase transition induced by pressure in the PbS and HgS nanocrystals was studied by in situ high pressure X-ray powder diffraction measurements. PbS underwent a phase transition from B1-B16 at 7 GPa whereas no transition was observed in HgS up to 15 GPa. The transition remained unaltered on the release of pressure. The volume decreased with an increase in pressure. There is a shift in transition pressure towards the higher side when compared with the bulk materials.
Alcohol: Anthropological/Archaeological Perspectives
Authors: Dietler Michael
Published: July 2006

Alcohol is a special form of embodied material culture and the most widely used psychoactive agent in the world. It has been a fundamentally important social, economic, political, and religious artifact for millennia. This review assesses trends in the anthropological engagement with alcohol during the past two decades since the Annual Review last covered this subject. It highlights the growing archaeological contributions to the field, as well as recent developments by sociocultural anthropologists and social historians. Increasing historicization has been a useful corrective to the earlier functionalist emphasis on the socially integrative role of drinking. Recent studies tend to employ a more strategic/agentive analytical framework and treat drinking through the lens of practice, politics, and gender. Moreover, alcohol has come to be seen as an important component of the political economy and a commodity centrally implicated in strategies of colonialism and postcolonial struggles over state power and household relations of authority.
Creolization and Its Discontents
Authors: Palmié Stephan
Published: July 2006

In the past two decades, analogies drawn from supposedly Caribbean processes of creolization have begun to command increasing interest in anthropology. Examining historical as well as contemporary social uses of this terminology in its region of origin, as well as linguistic, sociocultural, and archaeological extrapolations from such usages, this review argues that although, as an analytical metaphor, “creolization” may appear to remedy certain deficits in long-standing anthropological agendas, the current unreflexive use of it is neither defensible on empirical grounds nor theoretically well advised. Yet while this review argues against further uncritical extensions of such metaphorics, it analyzes their current proliferation as a social phenomenon worthy of anthropological analysis in its own right.
Diet in EarlyHomo: A Review of the Evidence and a New Model of Adaptive Versatility
Authors: Ungar Peter S. , Grine Frederick E. , Teaford Mark F.
Published: July 2006

Several recent studies have stressed the role of dietary change in the origin and early evolution of our genus in Africa. Resulting models have been based on nutrition research and analogy to living peoples and nonhuman primates or on archeological and paleoenvironmental evidence. Here we evaluate these models in the context of the hominin fossil record. Inference of diet from fossils is hampered by small samples, unclear form-function relationships, taphonomic factors, and interactions between cultural and natural selection. Nevertheless, craniodental remains of Homo habilis, H. rudolfensis, and H. erectus offer some clues. For example, there appears to be no simple transition from an australopith to a Homo grade of dietary adaptation, or from closed forest plant diets to reliance on more open-country plants or animals. Early Homo species more likely had adaptations for flexible, versatile subsistence strategies that would have served them well in the variable paleoenvironments of the African Plio-Pleistocene.
The Ethnography of Finland
Authors: Siikala Jukka
Published: July 2006

Different national traditions define disciplines in different ways, and ethnology, folklore, and anthropology are separated in the Finnish university system. The great divide between the more universally oriented anthropological research and the local, especially Eastern and Northern European ethnological traditions is sometimes conceptualized by defining the latter as nationalist. The emergence of Finnish and Finno-Ugric studies in Finland complicates the difference in a way that is relevant to urgent questions of globalization and its relationship to cultural diversity. At the same time this emergence raises important questions about the significance of ethnographic knowledge. Historically oriented ethnological and folkloristic studies in Finland have formulated a multidisciplinary approach analogical to the four anthropological fields for research into the history of Finnish and Finno-Ugric cultures and languages. Researchers have used the accumulated data in new and novel ways, which has opened up perspectives instead of limiting them to the field of area studies. The development of Finnish ethnographic studies clearly demonstrates the necessity of comparison and the comparative perspective.
The Research Program of Historical Ecology
Authors: Balée William
Published: July 2006

Historical ecology is a new interdisciplinary research program concerned with comprehending temporal and spatial dimensions in the relationships of human societies to local environments and the cumulative global effects of these relationships. Historical ecology contains core postulates that concern qualitative types of human-mediated disturbance of natural environments and the effect of these on species diversity, among other parameters. A central term used in historical ecology to situate human behavior and agency in the environment is the landscape, as derived from historical geography, instead of the ecosystem, which is from systems ecology. Historical ecology is similar to nonequilibrium dynamic theory, but differs in its postulate of human-mediated disturbance as a principle of landscape transformation. Such disturbances counterintuitively may involve anthropogenic primary and secondary succession that result in net increases of alpha and even beta diversity. Applied historical ecology can supply the reference conditions of time depth and traditional knowledge to restore past landscapes.
Institutional Failure in Resource Management
Authors: Acheson James M.
Published: July 2006

Many of the world's natural resources are in a state of crisis. The solution to this crisis is to develop effective management institutions, but there is no consensus on what those institutions are. Some economists favor solving resource-management problems through the institution of private property; others advocate central government control; and many anthropologists see local-level management as the solution. In this review, I argue that all these governance structures fail under certain conditions. However, the factors contributing to failure in each of these institutional forms differ radically, and the causes of that failure are not always predicted on the basis of existing theory. This chapter contains a review of the literature on the factors identified as causing the failure of private-property regimes, government-controlled resources, and local-level management. We will have to learn to match the resource problems with governance institutions and specific management techniques if we are to manage resources effectively. We also will have to understand the complex biosocial factors influencing sustainability.
What Cultural Primatology Can Tell Anthropologists about the Evolution of Culture
Authors: Perry Susan E.
Published: July 2006

This review traces the development of the field of cultural primatology from its origins in Japan in the 1950s to the present. The field has experienced a number of theoretical and methodological influences from diverse fields, including comparative experimental psychology, Freudian psychoanalysis, behavioral ecology, cultural anthropology, and gene-culture coevolution theory. Our understanding of cultural dynamics and the evolution of culture cannot be complete without comparative studies of (a) how socioecological variables affect cultural transmission dynamics, (b) the proximate mechanisms by which social learning is achieved, (c) developmental studies of the role of social influence in acquiring behavioral traits, and (d) the fitness consequences of engaging in social learning.
Genetic Polymorphism in Heterogeneous Environments: The Age of Genomics
Authors: Hedrick Philip W.
Published: July 2006

The selective mechanisms for maintaining polymorphism in natural populations has been the subject of theory, experiments, and review over the past half century. Advances in molecular genetic techniques have provided new insight into many examples of balancing selection. In addition, new theoretical developments demonstrate how diversifying selection over environments may maintain polymorphism. Tests for balancing selection in the current generation, the recent past, and the distant past provide a comprehensive approach for evaluating selective impacts. In particular, sequenced-based tests provide new ways to evaluate the long-term impact of selection on particular genes and the overall genome in natural populations. Overall, there appear to be many loci exhibiting the signal of adaptive directional selection from genomic scans, but the present evidence suggests that the proportion of loci where polymorphism is maintained by environmental heterogeneity is low. However, as more molecular genetic details become available, more examples of polymorphism maintained by selection in heterogeneous environments may be found.
Impact of Extreme Temperatures on Parasitoids in a Climate Change Perspective
Authors: Hance Thierry , van Baaren Joan , Vernon Philippe , Boivin Guy
Published: July 2006

Parasitoids depend on a series of adaptations to the ecology and physiology of their hosts and host plants for survival and are thus likely highly susceptible to changes in environmental conditions. We analyze the effects of global warming and extreme temperatures on the life-history traits of parasitoids and interactions with their hosts. Adaptations of parasitoids to low temperatures are similar to those of most ectotherms, but these adaptations are constrained by the responses of their hosts. Life-history traits are affected by cold exposure, and extreme temperatures can reduce endosymbiont populations inside a parasitoid, eventually eliminating populations of endosymbionts that are susceptible to high temperatures. In several cases, divergences between the thermal preferences of the host and those of the parasitoid lead to a disruption of the temporal or geographical synchronization, increasing the risk of host outbreaks. A careful analysis on how host-parasitoid systems react to changes in temperature is needed so that researchers may predict and manage the consequences of global change at the ecosystem level.
Arthropod Pest Management in Organic Crops
Authors: Zehnder Geoff , Gurr Geoff M. , Kühne Stefan , Wade Mark R. , Wratten Steve D. , Wyss Eric
Published: July 2006

Burgeoning consumer interest in organically produced foods has made organic farming one of the fastest growing segments of agriculture. This growth has not been supported adequately by rigorous research to address challenges such as arthropod pest management. The research that has been conducted, however, is complemented by research in aspects of conventional agriculture that may have applicability in organic systems, as well as by research in underpinning fields such as applied ecology. This article synthesizes the available literature in relation to a conceptual model of arthropod pest management strategies suitable for organic systems. The present work uses the four phases of the model to review the strategies in an agroecological context and provides a synthesis of the factors that influence the success of each phase. Rather than constituting a fringe science, pest management research for organic systems draws on cutting edge science in fields such as landscape and chemical ecology and has a bright future.
Origins and Evolution of Spliceosomal Introns
Authors: Rodríguez-Trelles Francisco , Tarrío Rosa , Ayala Francisco J.
Published: July 2006

Research into the origins of introns is at a critical juncture in the resolution of theories on the evolution of early life (which came first, RNA or DNA?), the identity of LUCA (the last universal common ancestor, was it prokaryotic- or eukaryotic-like?), and the significance of noncoding nucleotide variation. One early notion was that introns would have evolved as a component of an efficient mechanism for the origin of genes. But alternative theories emerged as well. From the debate between the “introns-early” and “introns-late” theories came the proposal that introns arose before the origin of genetically encoded proteins and DNA, and the more recent “introns-first” theory, which postulates the presence of introns at that early evolutionary stage from a reconstruction of the “RNA world.” Here we review seminal and recent ideas about intron origins. Recent discoveries about the patterns and causes of intron evolution make this one of the most hotly debated and exciting topics in molecular evolutionary biology today.
Soil To Genomics: The Streptomyces Chromosome
Authors: Hopwood David A.
Published: July 2006

The 8–9-Mb Streptomyces chromosome is linear, with a “core” containing essential genes and “arms” carrying conditionally adaptive genes that can sustain large deletions in the laboratory. Bidirectional chromosome replication from a central oriC is completed by “end-patching,” primed from terminal proteins covalently bound to the free 5′-ends. Plasmid-mediated conjugation involves movement of double-stranded DNA by proteins resembling other bacterial motor proteins, probably via hyphal tip fusion, mediated by these transfer proteins. Circular plasmids probably transfer chromosomes by transient integration, but linear plasmids may lead the donor chromosome end-first into the recipient by noncovalent association of ends. Transfer of complete chromosomes may be the rule. The recipient mycelium is colonized by intramycelial spreading of plasmid copies, under the control of plasmid-borne “spread” genes. Chromosome partition into prespore compartments of the aerial mycelium is controlled in part by actin- and tubulin-like proteins, resembling MreB and FtsZ of other bacteria.
Discovering DNA Encodes Heredity and Prions are Infectious Proteins
Authors: Prusiner Stanley B. , McCarty Maclyn
Published: July 2006

The resemblance between the discoveries that DNA is the basis of heredity and that prions are infectious proteins is remarkable. Though four decades separated these two discoveries, the biochemical methodologies and scientific philosophies that were employed are surprisingly similar. In both cases, bioassays available at the time that the projects were initiated proved to be inadequate to support purification studies. Improved bioassays allowed the transforming principle (TP) to be purified from pneumococci and prions from scrapie-infected hamster brains. Publications describing TP as composed of DNA prompted some scientists to contend that undetected proteins must contaminate TP enriched fractions. The simplicity of DNA was thought to prevent it from encoding genetic information. By the time prions were discovered, the genomes of all infectious pathogens including viruses, bacteria, fungi and parasites had been shown to be comprised of nucleic acids and so an antithetical refrain became widely echoed: DNA or RNA molecules must be hiding among the proteins of prions. Finding the unexpected and being asked to demonstrate unequivocally the absence of a possible contaminant represent uncanny parallels between the discoveries that DNA encodes the genotype and that prions are infectious proteins.
From the Cold War to Kosovo: The Rise and Renewal of the Field of International Human Rights
Authors: Dezalay Yves , Garth Bryant
Published: July 2006

▪ Abstract  This review explores the creation and transformation of the field of international human rights in the period after World War II. The narrative proceeds through an examination, based on documentary evidence and interviews, of three generations of human rights nongovernmental organizations: the International Commission of Jurists, Amnesty International, and Human Rights Watch. Each was created in part to overcome the limitations of the previous generation, and the process, linked to developments in the U.S. field of state power and U.S. activities abroad—especially in Latin America—gradually produced a field with substantial legal autonomy. At the same time, however, the structure of the field moved increasingly close to U.S. power and the issues and strategies that would gain credibility in the United States. The autonomy is therefore structurally close to U.S. power.
Conspiracy in International Law
Authors: Meierhenrich Jens
Published: July 2006

▪ Abstract  This review examines the function of conspiracy in international law, with particular reference to the jurisprudence of international ad hoc tribunals. It compares and contrasts the function of conspiracy law in the prosecution of international crimes before the International Military Tribunal (IMT) at Nuremberg following World War II, where the concept gave rise to a remarkably innovative and highly controversial conspiracy theory that revolved around the concept of “criminal organization,” and the function of conspiracy law in the prosecution of international crimes before the International Criminal Tribunal for the Former Yugoslavia (ICTY) at The Hague, where the concept has left a mark on a similarly innovative and equally controversial conspiracy theory that revolves around the concept of “joint criminal enterprise.” By tracing the function of conspiracy, this most controversial of U.S. legal transplants, in the international system, the review illuminates the significance of group dynamics in international law.
Law and the Labor Market
Authors: Jolls Christine
Published: July 2006

▪ Abstract  Legal rules governing the employer-employee relationship are many and varied. This review is concerned with the economic analysis of such rules. The review focuses on areas of employment regulation that have not been reviewed elsewhere from an economic perspective. Topics considered in the review include workplace safety regulation, privacy protection in the workplace, fringe benefits mandates, targeted mandates such as medical and family leave, and rules requiring that employees receive overtime pay. Both economic theory and empirical evidence are considered.
Hadronic Parity Violation: A New View Through the Looking Glass
Authors: Ramsey-Musolf Michael J. , Page Shelley A.
Published: July 2006

▪ Abstract  Studies of the strangeness-changing hadronic weak interaction have produced a number of puzzles that have evaded a complete explanation within the Standard Model. Their origin may lie either in dynamics peculiar to weak interactions involving strange quarks or in more general aspects of the interplay between strong and weak interactions. In principle, studies of the strangeness-conserving hadronic weak interaction using parity-violating hadronic and nuclear observables provide a complementary window to this question. However, progress in this direction has been hampered by the lack of a suitable theoretical framework for interpreting hadronic parity violation measurements in a model-independent way. Recent work involving effective field theory ideas has led to the formulation of such a framework, simultaneously motivating the development of a number of new hadronic parity violation experiments in few-body systems. We review these recent developments and discuss the prospects and opportunities for further experimental and theoretical progress.
Phase Transitions in the Early and Present Universe
Authors: Boyanovsky D. , de Vega H.J. , Schwarz D.J.
Published: July 2006

▪ Abstract  The evolution of the universe is the ultimate laboratory for studying fundamental physics across energy scales that span approximately 25 orders of magnitude. The standard models of cosmology and particle physics provide the basic understanding of the early and present universe and predict a series of phase transitions that occurred in succession during the universe's expansion and cooling history. We survey these phase transitions, highlighting the equilibrium and nonequilibrium effects as well as their observational and cosmological consequences. We discuss the current theoretical and experimental programs studying phase transitions in QCD and nuclear matter in accelerators. A critical assessment of similarities and differences between the conditions in the early universe and those in ultrarelativistic heavy ion collisions is presented. Cosmological observations and accelerator experiments are converging toward an unprecedented understanding of the early and present universe.
Impact of androgen-induced oxidative stress on hypertension in male SHR
Authors: Iliescu Radu , Cucchiarelli Valeria E. , Yanes Licy L. , Iles Joshua W. , Reckelhoff Jane F.
Published: July 2006

Men have higher blood pressure than women, and androgens and oxidative stress have been implicated as playing roles in this sexual dimorphism. The spontaneously hypertensive rat (SHR) is an animal model of both androgen- and oxidative stress-mediated hypertension. Therefore, the present studies were performed to test the hypothesis that androgens cause hypertension in SHR in part by stimulating superoxide production via NADPH oxidase. Castration of male SHR reduced blood pressure by 15% and attenuated both basal and NADPH-stimulated superoxide production in kidney cortical homogenates. Expression of p47phox and gp91phox but not p22phox subunits of NADPH oxidase were significantly lower in kidney cortex from castrated males compared with intact males. Moreover, inhibition of NADPH oxidase with apocynin caused ∼15 mmHg reduction in blood pressure and reduced basal and NADPH-stimulated superoxide production in intact male SHR, but had no effect on blood pressure or superoxide production in castrated males. These data support the hypothesis that androgens cause oxidative stress and thereby increase blood pressure in male SHR via an NADPH oxidase-dependent mechanism.
Gastrointestinal Motility: An Academic and Research Perspective
Authors: Quigley Eamonn M.M.
Published: July 2006

While, in the past, gastrointestinal motility may have been viewed as a narrow and restricted field, confined to the study of twitches in muscle baths and squiggles on smoke drums, it has, of late and belatedly, entered into the mainstream of gastroenterology and medicine. As a consequence, this field, now more correctly and appropriately described as neurogastroenterology, concerns itself with a vast spectrum of clinical disorders of varying pathophysiology, presentation and management. Never before has this area offered so many opportunities to the budding academician and researcher.
Training in Gastrointestinal Motility
Authors: Parkman Henry P.
Published: July 2006

Gastrointestinal (GI) motility and functional GI disorders are common reasons for patients to see gastroenterologists. Knowledge of the evaluation and treatment of these disorders is important to appropriately care for these patients in clinical practice. Training in GI motility is important to GI fellows and their subsequent role as gastroenterologists. The aim of this paper is to discuss the importance of GI motility disorders for trainees in gastroenterology, provide some suggestions for training activities for GI fellows in GI motility, and discuss ways to address the unmet clinical need for caring for patients with GI motility disorders that gastroenterologists routinely see in their clinical practice.
Gastrointestinal Motility Disorders: An Update
Authors: Lacy Brian E. , Weiser Kirsten
Published: July 2006

Gastrointestinal motility disorders encompass a wide array of signs and symptoms that can occur anywhere throughout the luminal gastrointestinal tract. Motility disorders are often chronic in nature and dramatically affect patients’ quality of life. These prevalent disorders cause a tremendous impact both to the individual patient and to society as a whole. Significant progress has been made over the last 5 years in understanding the etiology and pathophysiology of gastrointestinal motility disorders. This clinical update will focus on seven of the most common gastrointestinal motility disorders (achalasia, non-achalasia esophageal motility disorders, dyspepsia, gastroparesis, chronic intestinal pseudo-obstruction, irritable bowel syndrome, and chronic constipation) with an emphasis on current treatment options and new therapeutic modalities.
New Directions in the Assessment of Gastric Function: Clinical Applications of Physiologic Measurements
Authors: Bratten Jason , Jones Michael P.
Published: July 2006

A variety of methods exist to assess gastric motor and sensory function. Specific techniques allow for the measurement of emptying, contractility, accommodation and sensation. Several of these techniques are suitable for in-office use rather than in a hospital or gastroenterology laboratory. While gastric function tests continue to proliferate and become more clinically accessible, their relevance to specific digestive symptoms or syndromes remains poorly studied. Additionally, the ability of gastric function testing to guide therapy or predict responses to interventions also remains poorly studied. Gastric function testing should be employed cautiously in clinical practice with an awareness that test results represent observations rather than diagnosis.
New Directions in Brain Imaging Research in Functional Gastrointestinal Disorders
Authors: Ringel Yehuda
Published: July 2006

Functional brain imaging has greatly enhanced the ability to investigate brain-gut interactions and to assess the central nervous system role on visceral pain perception. The results of studies using brain imaging in irritable bowel syndrome (IBS) have demonstrated differences in brain activation between patients with IBS and healthy controls. In addition, the more recent studies are starting to shed light on pathophysiological mechanisms that underlie the generation of functional gastrointestinal (GI) symptoms as well as the response to treatment. These studies highlight the potential of functional brain imaging to become an important and exciting investigative tool in research of functional GI disorders. However, the multifactorial, multideterminant nature of these disorders, the current limitations in the understanding of the pathophysiology of the disorders, and the heterogeneous patient population make brain imaging research in this field difficult and require caution in the interpretation of the data. The continued development of brain imaging techniques provides not only exciting opportunities but also significant challenges to the field. This article focuses on brain imaging research in functional GI disorders. It describes some of the recent developments in the use of brain imaging in research of the brain-gut axis and provides an overview of the current data.