bluuebunny/crossref_metadata_2025 huggingface dataset:
Packaging policies to reform the water sector: The case of the Central Valley Project Improvement Act
Authors: Fischhendler Itay , Zilberman David
Published: July 2005

Existing water policies often deviate from measures suggested by economic and environmental analysis. This is particularly true in the case of drought response policies, where effective policies are rarely adopted. This study focuses on how to enhance the political feasibility of options rather than identifying the optimal water policies. It argues that a legislative policy package may be a mechanism both to unite divergent interest groups into a coalition with common policy agendas and also to fragment or realign existing and traditional alliances. This majority building approach may have a greater chance of obtaining the required political support to advance water reforms. The negotiation over the Central Valley Project Improvement Act in California is used as an example. The case study illustrates how the policy packaging strategy split the traditional power alliance between the agricultural sector and the urban sector in California and between the agricultural sector in California and their allies in other U.S. western states. At the same time, policy packaging has created new regional and sectoral advocacy coalitions in support of water reform. As a result, the Bureau of Reclamation changed its policies in the Central Valley in California relating to the establishment of water markets, water pricing, and wildlife restoration fund and allocating water for the environment.
On the transient nature of mantle plumes
Authors: Davaille Anne , Vatteville Judith
Published: July 2005

We present new experiments focussing on the transient behaviour of thermal plumes. In a fluid heated from below, plumes develop once the hot thermal boundary layer (TBL) reaches a critical thickness (Howard, 1964). They rise through the fluid owing to their thermal buoyancy and comprise TBL material which empties itself into the plumes. As the TBL becomes exhausted, plumes start disappearing from the bottom up, sometimes even before reaching the upper boundary, depending on the convection intensity. Then, they finally fade away by thermal diffusion. This sequence of events shows that time‐dependence is a key‐factor when interpreting present‐day tomographic images of mantle upwellings. In particular, it could be erroneous to identify the depth of a present‐day slow seismic anomaly with the depth of its origin, or to interpret the absence of a long tail as the absence of a plume.
Transition of low‐salinity water in the Western Pacific Warm Pool recorded in the nitrogen isotopic ratios of settling particles
Authors: Yoshikawa Chisato , Nakatsuka Takeshi , Kawahata Hodaka
Published: July 2005

We analyzed nitrogen isotopic ratio (δ15N) of settling particles at four sites in the western and central equatorial Pacific from January to November 1999, together with the δ15N of nitrate above 200 m depth in December 1999. The δ15N values of settling particles at the two western sites (station 1 and 2) were about 3.0 ‰ more depleted than that at the most eastern site (station 9). In March 1999, the δ15N values rose from 3.7 ‰ to 7.2 ‰ at station 3 located at 0°N 145°E. During this month, the salinity at this site also increased by 0.4 psu, suggesting that low‐salinity water had shifted to the west. The relationship between salinity and δ15N of nitrate in surface water suggested that the depleted δ15N reflects river discharge, atmospheric deposition and/or nitrogen fixation. Thus, we were able to reconstruct the transition of low‐salinity water in the WPWP based on the δ15N values of settling particles.
On the robustness of the estimates of centennial‐scale variability in heavy precipitation from station data over Europe
Authors: Zolina Olga , Simmer Clemens , Kapala Alice , Gulev Sergey
Published: July 2005

The impact of missing values on the centennial‐scale variability of heavy precipitation was analysed using daily data from European rain gauges. Sub‐sampling was modeled according to the observed structure of gaps in daily precipitation records. Quantitative estimates of the sampling impact on the long‐term variability derived from high‐quality long‐term station data were used for the homogenization of sampling in European time series and the estimation of long‐term secular tendencies in heavy precipitation indices. Centennial linear trends of extreme precipitation based on different indices are quite robust in winter but less robust in summer, implying seasonality in the trend estimates especially in Western Europe. Estimates of annual indices derived for the locations where different indices shows significant trends imply primarily positive centennial‐scale changes in heavy and very heavy precipitation with the strongest magnitudes of about 3–5% per decade in Eastern Europe.
A novel insulin derivative chemically modified with dehydrocholic acid: synthesis, characterization and biological activity
Authors: Huang Tao , Huang Kaixun
Published: July 2005

A novel chemically modified insulin, ε‐NB29‐DHC‐insulin (where DHC‐insulin stands for dehydrocholyl‐insulin), was prepared by covalent linkage of DHC (dehydrocholic acid) to the ε‐amino group of LysB29 without any protecting agent and analysed by PAGE and reversed‐phase HPLC. DHC‐insulin was identified by MALDI–TOF‐MS (matrix‐assisted laser‐desorption ionization–time‐of‐flight MS) coupled with dithiothreitol and trypsin treatment. The major product, mono‐DHC‐insulin, was ε‐NB29‐DHC‐insulin. The biological activity of the modified insulin was evaluated by measuring the in vivo hypoglycaemic effect and in vitro tryptic degradation. Mono‐DHC‐insulin maintained the glucose‐lowering effect as strongly as native insulin, showed a significantly slower disappearance due to an increase of its receptor‐binding potency and retained approx. 40% of the reduced glucose relative to the undegraded sample digested for 6 h with trypsin in vitro. These results suggested that ε‐NB29‐DHC‐insulin showed a longer duration of action compared with native insulin and also a protective effect from tryptic degradation.
Podophyllum hexandrum (Himalayan mayapple) extract provides radioprotection by modulating the expression of proteins associated with apoptosis
Authors: Kumar Raj , Singh Pankaj Kumar , Sharma Ashok , Prasad Jagdish , Sagar Ravinder , Singh Surender , Arora Rajesh , Sharma Rakesh Kumar
Published: July 2005

Podophyllum hexandrum Royale (Himalayan mayapple), a high‐altitude Himalayan plant, has been shown to provide over 80% whole‐body radioprotection in mice. To investigate the radioprotective potential of P. hexandrum at the molecular level, expression patterns of various proteins associated with apoptosis were studied in the spleen of male Swiss albino strain A mice by immunoblotting. Treatment with P. hexandrum [200 mg/kg of body weight; an ethanolic 50% (w/v) extract delivered intraperitoneally] 2 h before irradiation resulted in MAPKAP (mitogen‐activated protein kinase‐activated protein) kinase‐2 activation along with HSF‐1 (heat‐shock transcription factor‐1), leading to up‐regulation of HSP‐70 (heat‐shock protein‐70) as compared with sham‐irradiated (10 Gy) mice. Strong inhibition of AIF (apoptosis‐inducing factor) expression was observed in the mice treated with P. hexandrum 2 h before irradiation as compared with the sham‐irradiated group. Inhibition in the translocation of free NF‐κB (nuclear factor κB) from cytoplasm to nucleus was observed upon P. hexandrum pretreatment 2 h before irradiation when compared with radiation‐treated mice. P. hexandrum pre‐treatment (2 h before irradiation) resulted in inhibition of NF‐κB translocation, and the expression of tumour suppressor protein p53 was observed to be down‐regulated as compared with sham‐irradiated control. An increase in the expression of proteins responsible for cell proliferation [Bcl‐2 (B‐cell chronic lymphocytic lymphoma 2), Ras‐GAP (Ras‐GTPase‐activating protein) and PCNA (proliferating cell nuclear antigen)] was observed in the P. hexandrum‐pretreated irradiated mice as compared with sham‐irradiated controls. Caspase 3 activation resulted PARP [poly(ADP‐ribose) DNA polymerase] cleavage, and DNA degradation was strongly inhibited in the mice treated with P. hexandrm (+/− irradiation) as compared with the mice treated with radiation (+/− heat shock). The present study thus clearly demonstrated that P. hexandrum extract provides protection from γ‐radiation by the modulation of expression of proteins associated with cell death.
Quantitative genotyping of single‐nucleotide polymorphisms by allele‐specific oligonucleotide hybridization on DNA microarrays
Authors: Rickert Andreas M. , Ballvora Agim , Matzner Ulrich , Klemm Manfred , Gebhardt Christiane
Published: July 2005

Genotyping of SNPs (single‐nucleotide polymorphisms) has challenged the development of several novel techniques [Twyman and Primrose (2003) Pharmacogenomics 4, 67–79]. Most of these methods have been introduced to discriminate binary SNPs in diploid species. In the present study, the quantitative genotyping of SNPs in natural DNA pools of a polyploid organism via DNA microarrays was analysed. Three randomly selected SNP loci were genotyped in the tetraploid species potato (Solanum tuberosum). For each SNP, 24 oligomers were designed, 12 with forward and 12 with reverse orientation. They contained the polymorphic site at one of the positions 11, 14 and 17. Several steps of optimizations were performed, including the ‘materials’ used and the establishment of hybridization conditions. Glass surfaces were either epoxy‐ or aldehyde‐modified, and allele‐specific oligonucleotides contained either SH or NH2 groups. Hybridization stringency conditions were established by varying the concentration of formamide in the hybridization buffer. For SNP BA213c14t7/403, the quantitative discrimination between all four different naturally occurring genotypes could be demonstrated.
Orientational order in smectic liquid-crystalline phases of amphiphilic diols
Authors: Giesselmann Frank , Germer Roland , Saipa Alexander
Published: July 2005

The thermotropic smectic phases of amphiphilic 2-(trans-4-n-alkylcyclohexyl)-propane-1,3-diols were investigated by means of small- and wide-angle x-ray scattering and values of the smectic (bi-)layer spacing, the orientational order parameters ⟨P2⟩ and ⟨P4⟩, the orientational distribution function as well as the intralayer correlation length were extracted from the scattering profiles. The results for the octyl homolog indicate that these smectic phases combine a very high degree of smectic one-dimensional-translational order with remarkably low orientational order, the order parameter of which (⟨P2⟩≈0.56) is far below those values typically found in nonamphiphilic smectics. This combination, quite exceptional in thermotropic smectics, most likely originates from the intermolecular hydrogen bonding between the terminal diol groups which seems to be the specific driving force in the formation of the thermotropic smectic structure in these amphiphiles and leads to a type of microphase segregation. Even in the absence of a solvent, the liquid-crystalline ordering of the amphiphilic mesogens comes close to the structure of the so-called neat soaps, found in lyotropic liquid crystals.
Collective domain-wall pinning of oxygen vacancies in bismuth titanate ceramics
Authors: Li Wei , Chen Aiping , Lu Xiaomei , Zhu Jinsong
Published: July 2005

Pure Bi4Ti3O12 ceramics were prepared using the conventional solid-state reaction method. In order to find the relationship between the ferroelectric properties and oxygen vacancies, we changed the concentration of oxygen vacancies inside the ceramics through different processes of oxygen treatment. Ferroelectric measurement reveals that both remnant polarization and fatigue resistance increase with the decreasing oxygen vacancies concentration. On the plot of dielectric loss as a function of temperature, a peak with the relaxation-type characteristic was observed at about 370 K with 100-Hz measuring frequency. This peak was associated with the migration of oxygen vacancies inside the ceramics and was well fitted using the Cole-Cole relation. The obtained broaden factor was found to be less than 1.0, which indicates that there was a strong correlation among those relaxation units. Therefore, in the domain-wall pinning fatigue mechanism, the migration of oxygen vacancies would demonstrate a collective behavior instead of an individual one. These results were further confirmed in Nd-modified Bi4Ti3O12 ceramics.
The effects of neodymium content and site occupancy on spontaneous polarization of epitaxial (Bi4−xNdx)Ti3O12 films
Authors: Watanabe Takayuki , Funakubo Hiroshi , Osada Minoru , Uchida Hiroshi , Okada Isao
Published: July 2005

Epitaxial (110)(Bi4−xNdx)Ti3O12(x=0–0.73) films with a variety of neodymium content were grown by metal-organic chemical-vapor deposition, and the effects of neodymium content and site occupancy on spontaneous polarization along the a axis were systematically investigated. Raman spectra revealed that the neodymium is selectively substituted for the bismuth (A site) in the pseudoperovskite layer up to x=0.45; however, with further increasing neodymium content, neodymium is also incorporated into other bismuth sites in the (Bi2O2)2+ layer. The neodymium substitution led to a continuous decrease in the Curie temperature. The saturated coercive field showed slight dependency on the neodymium content, while the remanent polarization significantly improved to a maximum of 34μC∕cm2 at x=0.35. The estimated value of the spontaneous polarization for the epitaxial films with x=0.26–0.45 exceeded 50μC∕cm2, i.e., the reported value for pure Bi4Ti3O12 single crystal, but markedly decreased at x=0.73. The degraded spontaneous polarization appeared to be associated with the site occupancy of the neodymium at the two different kinds of bismuth sites.
Raman spectroscopy of single-wall carbon nanotubes and graphite irradiated by γ rays
Authors: Hulman Martin , Skákalová Viera , Roth Siegmar , Kuzmany Hans
Published: July 2005

Graphite and single-wall carbon nanotubes irradiated by γ rays of energy of 1.3 MeV were investigated by Raman spectroscopy. Irradiation generates defects in the lattice as confirmed by the increase of the intensity of the defect-induced D line in both materials. On the other hand, the intensity of the radial breathing mode of nanotubes is lowered. The intensity of the G line does not change for graphite but increases for carbon nanotubes. For the latter, this behavior cannot be explained by the defect-mediated double-resonance mechanism. Softening of the q=0 selection rule is suggested as a way to explain the results.
Effect of ZrO2 incorporation into high dielectric Gd2O3 film grown on Si(111)
Authors: Park S. A. , Roh Y. S. , Kim Y. K. , Baeck J. H. , Noh M. , Jeong K. , Cho M.-H. , Chang C. H. , Joo M. K. , Kim T. G. , Song J. H. , Ko D.-H.
Published: July 2005

Gd 2 O 3 films, in which ZrO2 was incorporated, were epitaxially grown on Si(111) using an electron-beam evaporation and effusion method. The crystalline structure and morphological characteristics were investigated by various measurements. A silicide layer was locally formed during the initial growth stage due to interactions between elemental Gd and Si in the Gd2O3 film, resulting in poor interfacial characteristics and extensive destruction of the crystalline structure. However, the incorporation of ZrO2 influenced the unit-cell structure of Gd2O3, which contains oxygen vacancies that is located diagonally, enhancing the structural stability owing to the effective suppression of the interfacial layer. The effect on the initial growth stage as the result of incorporation improves the crystalline quality of the epitaxial Gd2O3 film and structural coherence between the film and substrate.
Dynamics of nonlinearly coupled magnetic-field-aligned electromagnetic electron-cyclotron waves near the zero-group-dispersion point in magnetized plasmas
Authors: Kourakis I. , Shukla P. K. , Morfill G. E.
Published: July 2005

The nonlinear coupling between two magnetic-field-aligned electromagnetic electron-cyclotron (EMEC) waves in plasmas is considered. Evaluating the ponderomotive coupling between the EMEC waves and quasistationary plasma density perturbations, a pair of coupled nonlinear Schrödinger equations (CNLSEs) is obtained. The CNLSEs are then used to investigate the occurrence of modulational instability in magnetized plasmas. Waves in the vicinity of the zero-group-dispersion point are considered, so that the group dispersion terms may either bear the same or different signs. It is found that a stable EMEC wave can be destabilized due to its nonlinear interactions with an unstable one, while a pair of unstable EMEC waves yields an increased instability growth rate. Individually stable waves remain stable while interacting with one another. Stationary nonlinear solutions of the coupled equations are presented. The relevance of our investigation to nonlinear phenomena in space plasmas is discussed.
Kinetic damping of toroidal Alfvén eigenmodes
Authors: Fu G. Y. , Berk H. L. , Pletzer A.
Published: July 2005

The damping of Toroidal Alfvén Eigenmodes in Joint European Torus (JET) [P. H. Rebut and B. E. Kenn, Fusion Technol.FUSTE811, 13 (1987)] plasmas is investigated by using a reduced kinetic model. Typically no significant damping is found to occur near the center of the plasma due to mode conversion to kinetic Alfvén waves. In contrast, continuum damping from resonance near the plasma edge may be significant, and when it is, it gives rise to damping rates that are compatible with the experimental observations.
Monopole-antimonopole and vortex rings
Authors: Teh Rosy , Wong Khai-Ming
Published: July 2005

The SU(2) Yang-Mills-Higgs theory supports the existence of monopoles, antimonopoles, and vortex rings. In this paper, we would like to present new exact static antimonopole-monopole-antimonopole (A-M-A) configurations. The net magnetic charge of these configurations is always −1, while the net magnetic charge at the origin is always +1 for all positive integer values of the solution’s parameter m. However, when m increases beyond 1, vortex rings appear coexisting with these AMA configurations. The number of vortex rings increases proportionally with the value of m. They are located in space where the Higgs field vanishes along rings. We also show that a single-point singularity in the Higgs field does not necessarily correspond to a structureless 1-monopole at the origin but to a zero-size monopole-antimonopole-monopole (MAM) structure when the solution’s parameter m is odd. This monopole is the Wu-Yang-type monopole and it possesses the Dirac string potential in the Abelian gauge. These exact solutions are a different kind of Bogomol’nyi-Prasad-Sommerfield (BPS) solutions as they satisfy the first-order Bogomol’nyi equation but possess infinite energy due to a point singularity at the origin of the coordinate axes. They are all axially symmetrical about the z-axis.
Cubic nitridation layers on sapphire substrate and their role in polarity selection of ZnO films
Authors: Wang Y. , Du X. L. , Mei Z. X. , Zeng Z. Q. , Ying M. J. , Yuan H. T. , Jia J. F. , Xue Q. K. , Zhang Z.
Published: July 2005

Well-defined cubic AlN ultrathin layers formed by nitridation of Al2O3 (0001) substrate at various temperatures were observed by high-resolution transmission electron microscopy. The polarity of the AlN layers strongly depends on the substrate pretreatment and nitridation temperature. The structure of the AlN layers plays a key role in polarity selection of subsequent ZnO films, and both Zn-polar and O-polar ZnO films could be steadily obtained by control of the cubic AlN layers.
Antiferromagnetism in bulk Zn1−xCoxO magnetic semiconductors prepared by the coprecipitation technique
Authors: Bouloudenine M. , Viart N. , Colis S. , Kortus J. , Dinia A.
Published: July 2005

Polycrystalline Zn1−xCoxO diluted magnetic semiconductors have been prepared by coprecipitation technique in the concentration range 0⩽x⩽0.1. Structure, composition analysis, and optical absorption measurements revealed that cobalt is incorporated into the lattice, as Co2+ substituting Zn2+ ions, forming a solid solution with wurtzite structure instead of Co precipitates. Room- and low-temperature magnetization measurements reveal a paramagnetic behavior for the Co-doped ZnO samples with a paramagnetic Co amount smaller than the nominal concentration. χT versus T evidenced that the remaining Co is antiferromagnetically coupled through oxygen. This is further supported by a simple model that shows that as the Co concentration increases the amount of nearest neighbors Co atoms increases thus giving antiferromagnetic coupling and reducing the paramagnetic contribution.
ZnO symmetric nanosheets integrated with nanowalls
Authors: Wang Ruey-Chi , Liu Chuan-Pu , Huang Jow-Lay , Chen Shu-Jen
Published: July 2005

Diverse ZnO integrated nanostructures, constructed by epitaxial nanowalls and symmetric single-crystalline nanosheets, were successfully synthesized via a strain-assisted self-catalyzed process at a low temperature of 500°C. The nanostructures started with the growth of ZnO nanowires, nucleated on a rugged ZnO single-crystalline film via a strain-assisted self-catalyzed growth mechanism. The nanowalls were then formed by the interconnection of the nanowires. Finally, the nanosheets were grown from the edges of the nanowalls. The growth mechanisms were supported by direct experimental evidence. Room-temperature cathodoluminance spectra show a relatively strong and sharp ultraviolet emission as well as a weak and broad green emission. The integrated nanostructure may be applied to develop self-inclusive nanoelectronics.
First-principles elastic stiffness of LaPO4 monazite
Authors: Wang Jingyang , Zhou Yanchun , Lin Zhijun
Published: July 2005

In this letter, the full set of elastic coefficients of LaPO4 monazite is presented based on the first-principles plane-wave pseudopotential total energy method. Mechanical parameters (bulk modulus, shear modulus, Young’s moduli, and Poisson’s ratio) are also presented and compared with experimental results for polycrystalline monazite. The responses of electronic structure and chemical bonds to a series of {010}⟨001⟩ shear strains are examined in order to study the mechanism of low shear strain resistance. The results show that small shear moduli originate from the inhomogeneous strengths of atomic bonds. For example, the weak La–O bonds accommodate the shear strain locally, while the PO4 tetrahedra are almost rigid. The theoretical elastic stiffness may be useful to understand the deformation mechanisms of LaPO4 monazite.
Agricultural Industrialization, Anticorporate Farming Laws, and Rural Community Welfare
Authors: Lyson Thomas A , Welsh Rick
Published: July 2005

The effect on rural communities of shifts in US agriculture toward a system dominated by large-scale industrial production is a central problematic in the sociology of agriculture. Despite the importance of agriculture structure and practice to US society, most research on this topic has been confined to specialized journals. And though research in this area has found negative effects on rural communities from agricultural industrialization, there is a dearth of inquiry into public policy remedies. Using data on 433 agriculture-dependent counties in the USA, we find that counties in states with laws that limit nonfamily corporate entry into farming score higher on important welfare indicators, and that the laws mitigate negative impacts on rural communities from industrial farming.
Agents, Cells, and Cities: New Representational Models for Simulating Multiscale Urban Dynamics
Authors: Batty Michael
Published: July 2005

New forms of representation at a fine spatial scale, in which units of space are conceived as cells and populations as individual agents, are currently changing the way we are able to simulate the evolution of cities. In this paper I show how these new approaches are consistent with traditional urban models that have gone before, with the emphasis no longer being on spatial interaction but on development dynamics and local movement. I first introduce ideas about urban simulation based on spatial evolution as reaction and diffusion, showing how problems conceived in terms of cells and/or agents enable new implementations of this generic model. I sketch the rudiments of cellular automata which emphasise rules for development transition, and agent-based models which focus on how individuals respond to environmental attributes encoded in cellular landscapes. I illustrate these exemplars through models of residential location. Three applications are then presented at very different spatial scales: pedestrian movement at the building scale, the evolution of systems of cities at a regional scale, and urban growth at the city scale. I conclude with proposals that formal policy analysis in this domain should always be informed by more than one approach.
Modulation of disease, T cell responses, and measles virus clearance in monkeys vaccinated with H-encoding alphavirus replicon particles
Authors: Pan Chien-Hsiung , Valsamakis Alexandra , Colella Teresa , Nair Nitya , Adams Robert J. , Polack Fernando P. , Greer Catherine E. , Perri Silvia , Polo John M. , Griffin Diane E.
Published: July 2005

Measles remains a major worldwide problem partly because of difficulties with vaccination of young infants. New vaccine strategies need to be safe and to provide sustained protective immunity. We have developed Sindbis virus replicon particles that express the measles virus (MV) hemagglutinin (SIN-H) or fusion (SIN-F) proteins. In mice, SIN-H induced high-titered, dose-dependent, MV-neutralizing antibody after a single vaccination. SIN-F, or SIN-H and SIN-F combined, induced somewhat lower responses. To assess protective efficacy, juvenile macaques were vaccinated with a single dose of 106or 108SIN-H particles and infant macaques with two doses of 108particles. A dose of 108particles induced sustained levels of high-titered, MV-neutralizing antibody and IFN-γ-producing memory T cells, and most monkeys were protected from rash when challenged with wild-type MV 18 months later. After challenge, there was a biphasic appearance of H- and F-specific IFN-γ-secreting CD4+and CD8+T cells in vaccinated monkeys, with peaks ≈1 and 3–4 months after challenge. Viremia was cleared within 14 days, but MV RNA was detectable for 4–5 months. These studies suggest that complete clearance of MV after infection is a prolonged, phased, and complex process influenced by prior vaccination.
Contributions of past and present human generations to committed warming caused by carbon dioxide
Authors: Friedlingstein Pierre , Solomon Susan
Published: July 2005

We developed a highly simplified approach to estimate the contributions of the past and present human generations to the increase of atmospheric CO
2
and associated global average temperature increases. For each human generation of adopted 25-year length, we use simplified emission test cases to estimate the committed warming passed to successive children, grandchildren, and later generations. We estimate that the last and the current generation contributed approximately two thirds of the present-day CO
2
-induced warming. Because of the long time scale required for removal of CO
2
from the atmosphere as well as the time delays characteristic of physical responses of the climate system, global mean temperatures are expected to increase by several tenths of a degree for at least the next 20 years even if CO
2
emissions were immediately cut to zero; that is, there is a commitment to additional CO
2
-induced warming even in the absence of emissions. If the rate of increase of CO
2
emissions were to continue up to 2025 and then were cut to zero, a temperature increase of ≈1.3°C compared to preindustrial conditions would still occur in 2100, whereas a constant-CO
2
-emissions scenario after 2025 would more than double the 2100 warming. These calculations illustrate the manner in which each generation inherits substantial climate change caused by CO
2
emissions that occurred previously, particularly those of their parents, and shows that current CO
2
emissions will contribute significantly to the climate change of future generations.
Apatite varieties in extant and fossil vertebrate mineralized tissues
Authors: Kallaste Toivo , Nemliher Jüri
Published: July 2005

A whole-pattern fitting of X-ray diffraction (XRD) patterns, including lattice-parameter and size–strain analysis, was elaborated and applied to a sample set of extant and fossil vertebrate tooth apatite. Recent and subfossil human tooth enamel and dentine, extant and fossil shark tooth enameloid, sarcopterygian and coelacanth tooth enamels were studied. As comparative materials, a modern coelacanth fish scale and a pharyngeal tooth of bony fish were used. It was found that the enamel apatite of human milk teeth had lattice parameter valuesa≃ 9.4 Å andc≃ 6.88 Å, which are close to the corresponding values of subfossil human teeth. The apatite of fossilized vertebrate teeth always has a loweralattice parameter (about 9.37 Å), while the lattice parametercappears to be more stable, being around 6.88 Å. The strain appears to be correlated with the lattice direction, being around ten times higher in the [hk0] direction. During fossilization, the strain diminished in the [00l] direction, but was random in the perpendicular [hk0] direction. The enamel tissues of vertebrates are built of two discrete crystallite series. About one-third of the human milk tooth enamel is composed of larger crystallites with dimensions of about 400 × 500 Å, and two-thirds of smaller crystallites with dimensions of about 50 × 150 Å. The latter range of dimensions is also characteristic for the crystallites forming the mineral part of human dentine and fish scales. Shark tooth enameloid is also built of two distinct series of apatite crystallites of different sizes and shapes. The larger crystallites (amounting to ∼15% of all crystallites) have approximate dimensions of 500 × 1000 Å, while the smaller ones are 400 × 500 Å. Both series are distinguishable in XRD patterns of modern, Jurassic and Devonian shark enamel.
Transforming the Developmental Welfare State in East Asia
Authors: Kwon Huck‐ju
Published: July 2005

This article attempts to explain changes and continuity in the developmental welfare states in Korea and Taiwan within the East Asian context. It first elaborates two strands of welfare developmentalism (selective vs. inclusive), and establishes that the welfare state in both countries fell into the selective category of developmental welfare states before the Asian economic crisis of 1997. The key principles of the selective strand of welfare developmentalism are productivism, selective social investment and authoritarianism; inclusive welfare development is based on productivism, universal social investment and democratic governance. The article then argues that the policy reform toward an inclusive welfare state in Korea and Taiwan was triggered by the need for structural reform in the economy. The need for economic reform, together with democratization, created institutional space in policy‐making for advocacy coalitions, which made successful advances towards greater social rights. Finally, the article argues that the experiences of Korea and Taiwan counter the neo‐liberal assertion that the role of social policy in economic development is minor, and emphasizes that the idea of an inclusive developmental welfare state should be explored in the wider context of economic and social development.
The Response to HIV/AIDS and the Construction of National Legitimacy: Lessons from Uganda
Authors: Parkhurst Justin O.
Published: July 2005

Uganda faces continual challenges as a low‐income nation reliant on international donors and non‐state actors. It was also one of the first countries to face a population‐wide HIV epidemic, a disease that can strain state capacity to its limits. One would expect that such a combination would weaken the governance structures in a developing country; yet, if anything, the Ugandan state has emerged from its HIV crisis with its legitimacy bolstered. This article reviews the Ugandan response to HIV/AIDS, analysing the ways in which the epidemic has provided a new arena for the Ugandan state to engage with international actors.
Food web changes in arctic ecosystems related to climate warming
Authors: Quinlan Roberto , Douglas Marianne S.V. , Smol John P.
Published: July 2005

Sedimentary records from three Canadian High Arctic ponds on Ellesmere Island, spanning the last several thousand years, show major shifts in pond communities within the last ∼200 years. These paleolimnological data indicate that aquatic insect (Diptera: Chironomidae) populations rapidly expanded and greatly increased in community diversity beginning in the 19th century. These invertebrate changes coincided with striking shifts in algal (diatom) populations, indicating strong food‐web effects because of climate warming and reduced ice‐cover in ponds. Predicted future warming in the Arctic may produce ecological changes that exceed the large shifts that have already occurred since the 19th century.
Oxygen effects on methane production and oxidation in humid tropical forest soils
Authors: Teh Yit Arn , Silver Whendee L. , Conrad Mark E.
Published: July 2005

We investigated the effects of oxygen (O2) concentration on methane (CH4) production and oxidation in two humid tropical forests that differ in long‐term, time‐averaged soil O2 concentrations. We identified sources and sinks of CH4 through the analysis of soil gas concentrations, surface emissions, and carbon isotope measurements. Isotope mass balance models were used to calculate the fraction of CH4 oxidized in situ. Complementary laboratory experiments were conducted to determine the effects of O2 concentration on gross and net rates of methanogenesis. Field and laboratory experiments indicated that high levels of CH4 production occurred in soils that contained between 9±1.1% and 19±0.2% O2. For example, we observed CH4 concentrations in excess of 3% in soils with 9±1.1% O2. CH4 emissions from the lower O2 sites were high (22–101 nmol CH4 m−2 s−1), and were equal in magnitude to CH4 emissions from natural wetlands. During peak periods of CH4 efflux, carbon dioxide (CO2) emissions became enriched in 13C because of high methanogenic activity. Gross CH4 production was probably greater than flux measurements indicated, as isotope mass balance calculations suggested that 48–78% of the CH4 produced was oxidized prior to atmospheric egress. O2 availability influenced CH4 oxidation more strongly than methanogenesis. Gross CH4 production was relatively insensitive to O2 concentrations in laboratory experiments. In contrast, methanotrophic bacteria oxidized a greater fraction of total CH4 production with increasing O2 concentration, shifting the δ13C composition of CH4 to values that were more positive. Isotopic measurements suggested that CO2 was an important source of carbon for methanogenesis in humid forests. The δ13C value of methanogenesis was between −84‰ and −98‰, which is well within the range of CH4 produced from CO2 reduction, and considerably more depleted in 13C than CH4 formed from acetate.
The effect of elevated atmospheric CO2 and drought on sources and sinks of isoprene in a temperate and tropical rainforest mesocosm
Authors: Pegoraro Emiliano , Abrell Leif , Van Haren Joost , Barron‐Gafford Greg , Grieve Katherine Ann , Malhi Yadvinder , Murthy Ramesh , Lin Guanghui
Published: July 2005

Isoprene is the most abundant volatile hydrocarbon emitted by many tree species and has a major impact on tropospheric chemistry, leading to formation of pollutants and enhancing the lifetime of methane, a powerful greenhouse gas. Reliable estimates of global isoprene emission from different ecosystems demand a clear understanding of the processes of both production and consumption. Although the biochemistry of isoprene production has been studied extensively and environmental controls over its emission are relatively well known, the study of isoprene consumption in soil has been largely neglected.

Here, we present results on the production and consumption of isoprene studied by measuring the following different components: (1) leaf and soil and (2) at the whole ecosystem level in two distinct enclosed ultraviolet light‐depleted mesocosms at the Biosphere 2 facility: a cottonwood plantation with trees grown at ambient and elevated atmospheric CO2 concentrations and a tropical rainforest, under well watered and drought conditions. Consumption of isoprene by soil was observed in both systems. The isoprene sink capacity of litter‐free soil of the agriforest stands showed no significant response to different CO2 treatments, while isoprene production was strongly depressed by elevated atmospheric CO2 concentrations. In both mesocosms, drought suppressed the sink capacity, but the full sink capacity of dry soil was recovered within a few hours upon rewetting. We conclude that soil uptake of atmospheric isoprene is likely to be modest but significant and needs to be taken into account for a comprehensive estimate of the global isoprene budget. More studies investigating the capacity of soils to uptake isoprene in natural conditions are clearly needed.
Drought‐induced nitrous oxide flux dynamics in an enclosed tropical forest
Authors: Van Haren Joost L. M. , Handley Linda L. , Biel Karl Y. , Kudeyarov Valery N. , McLain Jean E. T. , Martens Dean A. , Colodner Debra C.
Published: July 2005

El Niño–La Niña cycles strongly influence dry and wet seasons in the tropics and consequently nitrous oxide (N2O) emissions from tropical rainforest soils. We monitored whole‐system and soil chamber N2O fluxes during 5‐month‐long droughts in the Biosphere 2 tropical forest to determine how rainfall changes N2O production. A consistent pattern of N2O flux changes during drought and subsequent wetting emerged from our experiments. Soil surface drying during the first days of drought, presumably increased gas transport out of the soil, which increased N2O fluxes. Subsequent drying caused an exponential decrease in whole‐system (4.0±0.1% day−1) and soil chamber N2O flux (8.9±0.8% day−1; south chamber; and 13.7±1.1% day−1; north chamber), which was highly correlated with soil moisture content. Soil air N2O concentration ([N2O]) and flux measurements revealed that surface N2O production persisted during drought. The first rainfall after drought triggered a N2O pulse, which amounted to 25% of drought‐associated reduction in N2O flux and 1.3±0.4% of annual N2O emissions. Physical displacement of soil air by water and soil chemistry changes during drought could not account for the observed N2O pulse. We contend that osmotic stress on the microbial biomass must have supplied the N source for pulse N2O, which was produced at the litter–soil interface. After the pulse, N2O fluxes were consistently 90% of predrought values. Nitrate change rate, nutrient, [N2O], and flux analyses suggested that nitrifiers dominated N2O production during the pulse and denitrifiers during wet conditions. N2O flux measurements in Biosphere 2, especially during the N2O pulse, demonstrate that large‐scale integration methods, such as flux towers, are essential for improving ecosystem N2O flux estimates.
Effect of elevated atmospheric CO2 on oviposition behavior in Manduca sexta moths
Authors: Abrell Leif , Guerenstein Pablo G. , Mechaber Wendy L. , Stange Gert , Christensen Thomas A. , Nakanishi Koji , Hildebrand John G.
Published: July 2005

Moths can detect changes in environmental carbon dioxide (CO2) with extremely high sensitivity, but the role of CO2 in the biology of these and other insects is not well understood. Although CO2 has been demonstrated to influence egg‐laying (oviposition) behavior of the pyralid moth Cactoblastis cactorum and nectar foraging of the sphingid moth Manduca sexta, information about the generalized role of CO2 in the behavioral biology of these species is lacking. Comparative data are necessary to properly assess how the behaviors of different species may be modified by steadily rising levels of greenhouse gases in the environment. Experiments carried out in Biosphere 2 addressed whether changes in ambient CO2 levels play a role in the oviposition behaviors of M. sexta moths. In the first series of experiments, oviposition was measured inside a flight cage with different levels of nearly ambient or elevated CO2 (400, 800 or 1200 ppm). For each concentration, hostplants used as oviposition sites were grown from seed at a CO2 level that matched the environment inside the flight cage. Under homogenous levels of CO2, we observed no significant difference in oviposition behavior at the concentrations tested. In a second series of experiments, two groups of hostplants, each surrounded by a mini free‐air CO2 enrichment (FACE) ring, were assembled inside a flight cage. In this choice test, a dynamic plume of artificially high CO2 was generated around one group of test plants, while ambient CO2 was released around the second (control) group. After eggs were counted on both plant groups, M. sexta females showed a small preference for ovipositing on the control plants. Therefore, in contrast to C. cactorum females tested under similar dynamic flow conditions, M. sexta female oviposition was not strongly inhibited by elevated CO2. To investigate this phenomenon further, we used electrophysiological recording and found that the CO2 receptor cells in M. sexta, unlike those in C. cactorum, are not readily affected by elevated levels of ambient CO2. These findings therefore suggest that elevated background levels of CO2 affect the physiology of the CO2 detection system of M. sexta to a lesser extent than that of C. cactorum, and this correlates well with the observed differences in oviposition behavior between the two species under elevated levels of environmental CO2. Hostplants of C. cactorum are crassulacean acid metabolism plants that generate nocturnal CO2 sinks on the cladode surfaces, whereas, M. sexta hostplants are nocturnal sources of respiratory CO2. We hypothesize that the abrupt and continuing increase in global ambient CO2 levels will differentially alter the behavior and physiology of moths that use CO2 sinks and sources as sensory cues to find hostplants.
Selective harvest of sooty shearwater chicks: effects on population dynamics and sustainability
Authors: HUNTER CHRISTINE M. , CASWELL HAL
Published: July 2005

Selectivity of harvest influences harvest sustainability because individuals with different characteristics contribute differently to population growth. We investigate the effects of selection based on chick weight on a traditional harvest of the sooty shearwater Puffinus griseus by Rakiura Maori in New Zealand.

We develop a periodic stage‐structured matrix population model and incorporate seasonal harvest of three weight classes of chicks. Intensity and selectivity of harvest are defined in terms of weight‐specific hazard functions.

We investigate the effect of harvest intensity and selectivity on population growth rate, λ, and the chick exploitation rate, E. We also consider the interaction of chick harvest and adult mortality.

λ decreases and E increases as harvest intensity increases. At low harvest intensities, selection has little effect on λ. At high harvest intensities, λ increases as selectivity increases because of the non‐linear relationship between harvest intensity and the probability of being harvested.

λ is determined almost completely by E, irrespective of the combination of harvest selectivity and intensity producing E. This is true for both general patterns of selectivity and specific patterns estimated from empirical data.

The elasticities of λ, the net reproductive rate and the generation time are unaffected by selectivity and show only small responses to harvest intensity.

Adult sooty shearwaters are killed as bycatch in long‐line and driftnet fisheries. Such mortality of adults has an effect on λ about 10‐fold greater than an equivalent level of chick harvest.

The sustainability of any combination of chick harvest and adult mortality depends on the resulting reduction in λ. We explore these results in relation to indices of sustainability, particularly the United States Marine Mammal Protection Act (MMPA) standards.
Predicting the growth of a small introduced muskox population using population prediction intervals
Authors: ASBJØRNSEN EINAR J. , SÆTHER BERNT‐ERIK , LINNELL JOHN D. C. , ENGEN STEINAR , ANDERSEN REIDAR , BRETTEN TORD
Published: July 2005

A key issue in ecology is the prediction of future population fluctuations. Such population predictions are fundamental for population‐viability analysis and are essential for assessing the implications of various management actions. Development of reliable population predictions is however, difficult because it requires estimation and modelling of the separate effects of the deterministic components of the population dynamics as well as the stochastic influences on the population fluctuations. Here we model the stochastic dynamics of an introduced population of muskox Ovibos moschatus in the Dovrefjell mountains of central Norway, using a simple model without density regulation. Our aim is to examine quantitatively factors affecting the accuracy of the population projections by applying the concept of Population Prediction Interval (PPI).

The long‐term growth rate was % = 0·0511, assuming no density dependence. The environmental variance was relatively large (= 0·0159). This gives a deterministic growth rate of r = 0·0591. However, accounting for losses due to various kinds of human activities resulted in a nearly doubling of s (% = 0·0980).

Autumn temperature and late winter snow depth were each able to explain a significant proportion of the annual variation in population growth rates.

The impact of environmental stochasticity made the PPI wide after only a few years. Uncertainties in the estimates of the population parameters were quite small and had a minor impact on the PPI.

A sensitivity analysis showed that ignoring demographic stochasticity led to an overestimate of the environmental variance , but that the impact on the width of the PPI was small.

This study shows that reliable projections of future population growth, even based on simple population models without density regulation, are dependent on assessment of the accuracy in the population predictions that must be based on estimating and modelling the stochastic influences on the population dynamics.
Egg size variation does not affect offspring performance under intraspecific competition in Nasonia vitripennis, a gregarious parasitoid
Authors: LALONDE R. G.
Published: July 2005

As with many insects, egg size variation is correlated with body size in the gregarious parasitoid, Nasonia vitripennis. I use this feature to test the hypothesis that egg size differences among parents affects the ability of their larvae to compete for limited resources within a superparasitized host.

I show that egg size asymmetries in parents that oviposit into the same host have no detectable effect on relative offspring performance, even under conditions of resource limitation.

Broods within a host that were initiated earlier attained greater average size than competing broods in the same host that were initiated later.

Individuals in the more numerous brood emerged consistently larger than individuals in the less numerous brood.

The possibility that siblings cooperate in competing for limited resources within a host and the potential role of sibling cooperation on egg size evolution is discussed.