bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relative contributions of archaea and bacteria to aerobic ammonia oxidation in the environment
Authors: Prosser James I. , Nicol Graeme W. 
Published: September 2008

SummaryTraditionally, organisms responsible for major biogeochemical cycling processes have been determined by physiological characterization of environmental isolates in laboratory culture. Molecular techniques have, however, confirmed the widespread occurrence of abundant bacterial and archaeal groups with no cultivated representative, making it difficult to determine their ecosystem function. Until recently, ammonia oxidation, the first step in the globally important process of nitrification, was thought to be performed almost exclusively by bacteria. Metagenome studies, followed by laboratory isolation, then demonstrated the potential for significant ammonia oxidation by mesophilic crenarchaea, whose ecosystem function was previously unknown. Re‐assessment of the role of bacteria in ammonia oxidation is now required and this article reviews the current evidence for the relative importance of bacteria and archaea. Much of this evidence is based on metagenomic analysis and molecular techniques for estimation of gene and gene transcript abundance, changes in ammonia oxidizer community structure during active nitrification and phylogeny of natural communities. These studies have been complemented by physiological characterization of a laboratory isolate and by incorporation of labelled substrates. Data from these studies provide increasingly convincing evidence for the importance of archaeal ammonia oxidizers in the global nitrogen cycle. They also highlight the need to re‐assess the importance of ammonia‐oxidizing bacteria, the requirement and limitations of molecular techniques in linking specific microbial groups to ecosystem function and the limitations of reliance on laboratory cultures.
TIME‐VARYING UNCERTAINTY AND THE CREDIT CHANNEL
Authors: Dorofeenko Victor , Lee Gabriel S. , Salyer Kevin D. 
Published: September 2008

ABSTRACTWe extend the Carlstrom and Fuerst (American Economic Review, 1997, 87, pp. 893–910) agency cost model of business cycles by including time‐varying uncertainty in the technology shocks that affect capital production. We first demonstrate that standard linearization methods can be used to solve the model yet second moments enter the economy's equilibrium policy functions. We then demonstrate that an increase in uncertainty causes, ceteris paribus, a fall in investment supply. We also show that persistence of uncertainty affects both quantitatively and qualitatively the behaviour of the economy.
‘SPRACHKULTUR’ IN LAY AND ACADEMIC DISCOURSE IN MODERN GERMANY1
Authors: Davies Winifred V. 
Published: September 2008

ABSTRACTThe term ‘Sprachkultur’ is common in German‐language academic and lay discourse, but what exactly does it mean? Is it used in the same way by trained and lay linguists? This article defines the term and traces its history, before going on to compare and contrast its use by both groups. Data taken from lay‐linguistic works are analysed and two recurring motifs (i. the link between morality and linguistic usage and ii. accuracy/clarity) are discussed to see what light they throw on conceptions of language and language use. The concluding section sums up the similarities and differences between lay and academic linguists. The latter tend to concentrate on ‘Sprachgebrauchskultur’ whereas the former are prepared to criticise the language system as well. The stress laid by lay linguists on accuracy and the link between morality and linguistic choices reflects a ‘telementational’ view of language which has major shortcomings, and appears to be rooted in a world‐view that equates diversity with cultural and ideological fragmentation rather than seeing it as enriching. However, the study of pronouncements by trained linguists shows that their work, too, reflects ideological assumptions about the nature of standard and other varieties of German.
SETTING THE STANDARD: USAGE LABELS IN ADVANCED MONOLINGUAL LEARNERS' DICTIONARIES OF GERMAN
Authors: Kirkness Alan 
Published: September 2008

ABSTRACTUsing lexical items from Martin Durrell's classification of register variation as a sample, the study investigates how the current advanced monolingual learners' dictionaries of German as an additional language treat such variation and indicate to their users what they consider to be standard usage: how do they set the standard? Abbreviated usage labels as conventionally found in dictionaries for first‐language users are the primary indications, and the dictionaries seldom go beyond such labels. German Standard German is the norm. At its core are unmarked or unlabelled items, while its range extends to include less formal items from everyday use, especially spoken, which are typically labelled umg. or gespr., and more formal items, more particularly found in written usage, which are labelled geh. or geschr. Non‐standard items, if entered as headwords, may be labelled derb or vulgär, veraltet or lit. No one dictionary stands out from the others as setting the standard in terms of treating register variation, and it must be questioned whether learners of German as an additional language would not be better served by more detailed, discursive information on different contexts of use and stylistic levels.
Dealing in Toxins on the Wrong Side of the Tracks: Lessons from a Hazardous Waste Controversy in Phoenix*
Authors: Sicotte Diane 
Published: September 2008

Objective.The controversial expansion of a hazardous waste facility in a poor, minority neighborhood in Phoenix illustrates the unanticipated consequences of siting hazardous facilities in vulnerable communities, and the need to recognize neighborhood health/safety issues such as drug‐related crime as environmental justice struggles.Methods.Qualitative methods include participant observation, document analysis, Census data, GIS mapping, and interviews.Results.South Central Phoenix's history reveals a disproportionate share of poverty, pollution, and drug crimes. Most commercial hazardous waste facilities in Phoenix were sited in minority areas. Residents contended that the siting, permitting process, and expansion of the facility and the drug crimes that later occurred there were all due to environmental racism.Conclusions.The expansion of the facility exacerbated environmental injustice in Phoenix through distributional and participative injustice, and was criminogenic. The dual impact on the community of hazardous waste and drug crime argues for a more holistic understanding of environmental justice.
Encouraging Pollution‐Free Energy: The Diffusion of State Net Metering Policies*
Authors: Stoutenborough James W. , Beverlin Matthew 
Published: September 2008

Objective. As the price of energy swells, renewable energy sources will serve as important alternatives to fossil fuels. Identifying what influences a state to adopt a policy that promotes the construction of renewable energy sources is an important step toward understanding the nature of our future energy supplies.Methods. Using an event‐history analysis, we examine three competing diffusion explanations on the likelihood of a state adopting net metering.Results. We find that regional policy diffusion influences the likelihood of a state to adopt a net metering policy.Conclusions. The results suggest that states are learning from one another and that the EPA's regional offices help facilitate this diffusion.
The Potential of Tree Rings for the Study of Forest Succession in Southern Mexico
Authors: Brienen Roel J. W. , Lebrija‐Trejos Edwin , Van Breugel Michiel , Pérez‐García Eduardo A. , Bongers Frans , Meave Jorge A. , Martínez‐Ramos Miguel 
Published: September 2008

ABSTRACTStudies of tropical secondary forest succession face strong limitations due to the slow pace of succession and the time‐consuming task of monitoring processes. The occurrence of tree rings in secondary forest trees may help expand our knowledge on succession in these systems and may be useful for fallow dating in chronosequence studies. We examine here the potential of tree rings to study forest succession by sampling 70 species along chronosequences of dry and wet forests in southern Mexico. Based on wood anatomical features, we estimated that about 37 percent of the species presented distinct growth rings useful for ring studies. Overall, maximum number of rings matched well the interview‐based fallow ages but, at some sites, trees had consistently higher numbers of rings, probably due to errors in fallow ages derived from interviews. Best fallow age estimations were obtained by examining rings in both pioneer and nonpioneer species. Reconstruction of species' establishment dates revealed that pioneer and nonpioneer species establish early during succession, and that species of both groups continue to recruit after many years. Our study clearly shows that tree ring analysis is a promising tool for studies on secondary forest succession in the tropics.
Litter Biomass and Nutrient Determinants of Ant Density, Nest Size, and Growth in a Costa Rican Tropical Wet Forest
Authors: McGlynn Terrence P. , Fawcett Ryan M. , Clark Deborah A. 
Published: September 2008

ABSTRACTThe nutritional demands of animals vary by taxon. Across landscapes, communities of animals experience variability in the stoichiometry of carbon and nutrients within their resource base. Thus, we expect stoichiometry to contribute to the spatial variance in the demographic parameters of animal communities. Here, we measure how the composition of a litter‐nesting tropical rainforest ant community is influenced by spatial variation in environmental stoichiometry relative to litter biomass, a known predictor of ant density. We found the density of ants and their nests were strongly related to litter biomass and carbon: phosphorus stoichiometry. The spatial variation in soil nutrients, which determines leaf litter stoichiometry, was an excellent predictor of nest size in the two most common genera of ants. We found a negative relationship between species' growth rate and local soil stocks of phosphorus. Overall, the density of litter‐dwelling ants varied greatly across this tropical forest landscape and environmental stoichiometry can account for limits on ant density independent of the biomass of the leaf litter resource base.
Population and Genetic Consequences of Hurricanes for Three Species of West Indian Phyllostomid Bats
Authors: Fleming Theodore H. , Murray Kevin L. 
Published: September 2008

ABSTRACTStrong hurricanes can cause population reductions in West Indian birds and bats, but the genetic consequences of such reductions have not been documented. For three species of phyllostomid bats, we report on the genetic effects of three strong hurricanes that struck the northern West Indies in 2004. Hurricane Ivan devastated Grand Cayman and severely depressed populations of several bat species. Despite being smaller than pre‐hurricane levels, the population of Artibeus jamaicensis (the only species we could resample) on Grand Cayman contained greater mitochondrial haplotype diversity but similar microsatellite allelic diversity compared to pre‐Ivan levels. We suggest that hurricane‐aided dispersal from Cayman Brac introduced two new haplotypes into the Grand Cayman population. In the Bahamas, two other phyllostomids (Erophylla sezekorni and Macrotus waterhousii) did not suffer population losses or changes in genetic diversity as a result of Hurricanes Frances and Jeanne. Our results suggest that strong hurricanes usually have greater demographic than genetic effects but that hurricane‐aided dispersal can occasionally introduce new genotypes or haplotypes into island bat populations.
What did we learn from gamma-ray burst 080319B?
Authors: Kumar P. , Panaitescu A. 
Published: September 2008

Abstract
The optical and gamma-ray observations of GRB 080319B allow us to provide a broad-brush picture for this remarkable burst. The data indicate that the prompt optical and gamma-ray photons were possibly produced at the same location but by different radiation processes: synchrotron and synchrotron self-Compton, respectively (but we note that this interpretation of the gamma-ray data faces some difficulties). We find that the burst prompt optical emission was produced at a distance of 1016.3 cm by an ultrarelativistic source moving at Lorentz factor of ∼500. A straightforward inference is that about 10 times more energy must have been radiated at tens of GeV than that released at 1 MeV. Assuming that the GRB outflow was baryonic and the gamma-ray source was shock-heated plasma, the collimation-corrected kinetic energy of the jet powering GRB 080319B was larger than 1052.3 erg. The decay of the early afterglow optical emission (up to 1 ks) is too fast to be attributed to the reverse-shock crossing the GRB ejecta but is consistent with the expectations for the ‘large-angle’ emission released during the burst. The pure power-law decay of the optical afterglow flux from 1 ks to 10 d is most naturally identified with the (synchrotron) emission from the shock propagating into a wind-like medium. However, the X-ray afterglow requires a departure from the standard blast-wave model.
In Vitro Activity of the Antifungal Plant Defensin RsAFP2 against
Candida
Isolates and Its In Vivo Efficacy in Prophylactic Murine Models of Candidiasis
Authors: Tavares Patricia M. , Thevissen Karin , Cammue Bruno P. A. , François Isabelle E. J. A. , Barreto-Bergter Eliana , Taborda Carlos P. , Marques Alexandre F. , Rodrigues Marcio L. , Nimrichter Leonardo 
Published: September 2008

ABSTRACT

We show that RsAFP2, a plant defensin that interacts with fungal glucosylceramides, is active against
Candida albicans
, inhibits to a lesser extent other
Candida
species, and is nontoxic to mammalian cells. Moreover, glucosylceramide levels in
Candida
species correlate with RsAFP2 sensitivity. We found RsAFP2 prophylactically effective against murine candidiasis.
Inhibition of
Toxoplasma gondii
by Indirubin and Tryptanthrin Analogs
Authors: Krivogorsky Bogdana , Grundt Peter , Yolken Robert , Jones-Brando Lorraine 
Published: September 2008

ABSTRACT

New drugs are needed for treatment of
Toxoplasma gondii
infections. We tested derivatives of principles found in
Isatis indigotica
for in vitro efficacy against
T. gondii
infection. Indirubin-3′-oxime analogs showed modest micromolar activity, while tryptanthrin derivatives displayed 50% inhibitory doses in the low nanomolar range. Tryptanthrins have potential as anti-
Toxoplasma
infection therapeutics.
Schistosoma mansoniEgg Antigen-Mediated Modulation of Toll-Like Receptor (TLR)-Induced Activation Occurs Independently of TLR2, TLR4, and MyD88
Authors: Kane Colleen M. , Jung Euihye , Pearce Edward J. 
Published: September 2008

ABSTRACTUnlike most pathogens, helminth parasites and their products induce strong Th2 responses, and dendritic cells (DCs) and macrophages exposed to helminth antigens generally fail to produce interleukin-12. Rather, it has been shown that helminth products such as soluble egg antigens (SEA; a soluble extract fromSchistosoma mansonieggs) inhibit the activation of DCs in response to classical Toll-like receptor (TLR) ligands such as lipopolysaccharide or CpG. Nevertheless, recent work has suggested that TLR4 and/or TLR2 plays an important role in the recognition of helminth products by DCs and macrophages and in the development of Th2 responses. Using DCs derived from TLR4−/−, TLR2−/−, or MyD88−/−mice, we have demonstrated that the ability of SEA to modulate DC activation is MyD88 independent and requires neither TLR4 nor TLR2. Moreover, TLR2 and TLR4 are not required for SEA-pulsed DCs to induce Th2 responses in naïve mice.
Schistosoma mansoniAntigens Modulate Experimental Allergic Asthma in a Murine Model: a Major Role for CD4+CD25+Foxp3+T Cells Independent of Interleukin-10
Authors: Pacífico Lucila G. G. , Marinho Fábio A. V. , Fonseca Cristina T. , Barsante Michele M. , Pinho Vanessa , Sales-Junior Policarpo A. , Cardoso Luciana S. , Araújo Maria Ilma , Carvalho Edgar M. , Cassali Geovanni D. , Teixeira Mauro M. , Oliveira Sergio C. 
Published: September 2008

ABSTRACTIn areas where schistosomiasis is endemic, a negative correlation is observed between atopy and helminth infection, associated with a low prevalence of asthma. We investigated whetherSchistosoma mansoniinfection or injection of parasite eggs can modulate airway allergic inflammation in mice, examining the mechanisms of such regulation. We infected BALB/c mice with 30S. mansonicercariae or intraperitoneally injected 2,500 schistosome eggs, and experimental asthma was induced by ovalbumin (OVA). The number of eosinophils in bronchoalveolar lavage fluid was higher in the asthmatic group than in asthmatic mice infected withS. mansonior treated with parasite eggs. Reduced Th2 cytokine production, characterized by lower levels of interleukin-4 (IL-4), IL-5, and immunoglobulin E, was observed in bothS. mansoni-treated groups compared to the asthmatic group. There was a reduction in the number of inflammatory cells in lungs ofS. mansoni-infected and egg-treated mice, demonstrating that bothS. mansoniinfection and the egg treatment modulated the lung inflammatory response to OVA. Only allergic animals that were treated with parasite eggs had increased numbers of CD4+CD25+Foxp3+T cells and increased levels of IL-10 and decreased production of CCL2, CCL3, and CCL5 in the lungs compared to the asthmatic group. Neutralization of IL-10 receptor or depletion of CD25+T cells in vivo confirmed the critical role of CD4+CD25+Foxp3+regulatory T cells in experimental asthma modulation independent of IL-10.
Design issues in client-server software maintenance
Authors: Mishra Deepti , Mishra Alok 
Published: September 2008

Software requires maintenance because there are often some errors remaining in the system that must be removed as they are discovered. Even without errors, software frequently undergoes change. The main reason is that software must be enhanced to include more features. Client-server software maintenance is not as simple as centralized software maintenance because client-server software systems are more complex than software for centralized systems.
Cost associated with software maintenance is top most cost in software development, so there is a need to develop software which has maintainability i.e. the ease with which a system can be maintained. Therefore, the design and development of client-server software systems should be done keeping in mind the maintainability of the resultant software systems. There are various design issues related with the maintainability of the software. If we take care of these issues at the time of design, then the resultant system will have better maintainability and thus maintenance efforts of such system will be reduced.
An Efficient, General-Purpose Technique for Identifying Storm Cells in Geospatial Images
Authors: Lakshmanan Valliappa , Hondl Kurt , Rabin Robert 
Published: September 2008

Abstract
Existing techniques for identifying, associating, and tracking storms rely on heuristics and are not transferrable between different types of geospatial images. Yet, with the multitude of remote sensing instruments and the number of channels and data types increasing, it is necessary to develop a principled and generally applicable technique. In this paper, an efficient, sequential, morphological technique called the watershed transform is adapted and extended so that it can be used for identifying storms. The parameters available in the technique and the effects of these parameters are also explained.
The method is demonstrated on different types of geospatial radar and satellite images. Pointers are provided on the effective choice of parameters to handle the resolutions, data quality constraints, and dynamic ranges found in observational datasets.
Social Work and Spirituality in a Secular Society
Authors: Crisp Beth R. 
Published: September 2008

• Summary: In an increasingly secular era which finds only a small minority of the population regularly participating in organized religion, there is emerging interest in how spirituality can be incorporated into social work practice. This article proposes one way in which this might occur in `deliberately secular' nations such as Australia. • Findings: A framework in which spirituality is considered to be an aspect of lived experience is proposed. Dimensions of life which can be incorporated into such a framework include life rituals, creativity, social action, and sense of place. • Applications : Conceptualizing spirituality in a way which does not use specifically religious language or concepts, may enable discussion of spiritual issues to be incorporated into social work practice when either practitioners or service users have or no religious background or affiliation or no shared religious background.
African Social Services in Peril
Authors: Laird Siobhan E. 
Published: September 2008

• Summary: Using Ghana as an illustrative case study, this article examines the ideology and intentions which underpin the Poverty Reduction Strategy Paper required for approval by the IMF and World Bank to qualify for debt relief under the Highly Indebted Poor Countries initiative. This article critically examines the functions assigned to governmental and non-governmental agencies within the social sector generally and the Department of Social Welfare specifically. Conditions at the Department of Social Welfare are explored through data gathered from semi-structured interviews with frontline social workers. These document the day-to-day realities of social work practice in Ghana and the relationship of the Department of Social Welfare with the non-governmental sector in the delivery of welfare services. • Findings: Social workers at the Department of Social Welfare report chronic under-funding which undermines even the most rudimentary activities. They also describe difficulties in holding NGOs to account due to the lack of logistical support and the inability to enforce compliance with statutory requirements. • Applications : Across the sub-Saharan region are government departments responsible for the delivery of social services and operating within the social policy frameworks created by the Poverty Reduction Strategy Papers required for debt relief. Evidence produced by this case study has implications for similar sub-Saharan countries implementing a social policy based on the neoliberal precepts if the New Policy Agenda.