1,198 research outputs found
Optimizing the scale of markets for water quality trading
Applying market approaches to environmental regulations requires establishing a spatial scale for trading. Spatially large markets usually increase opportunities for abatement cost savings but increase the potential for pollution damages (hot spots), vice versa for spatially small markets. We develop a coupled hydrologic-economic modeling approach for application to point source emissions trading by a large number of sources and apply this approach to the wastewater treatment plants (WWTPs) within the watershed of the second largest estuary in the U.S. We consider two different administrative structures that govern the trade of emission permits: one-for-one trading (the number of permits required for each unit of emission is the same for every WWTP) and trading ratios (the number of permits required for each unit of emissions varies across WWTP). Results show that water quality regulators should allow trading to occur at the river basin scale as an appropriate first-step policy, as is being done in a limited number of cases via compliance associations. Larger spatial scales may be needed under conditions of increased abatement costs. The optimal scale of the market is generally the same regardless of whether one-for-one trading or trading ratios are employed
Enhanced bipolar fatigue resistance in CaZrO3-modified (K,Na) NbO3 lead-free piezoceramics
The bipolar fatigue behavior of (K,Na) NbO3 (KNN)-based lead-free piezoceramics was investigated. A comparative analysis demonstrated that CaZrO3-modified KNN ceramics exhibited highly enhanced bipolar fatigue resistance due to the reduced lattice distortion (c/a ratio) and coexistence of orthorhombic and tetragonal phases. The hypothesis was verified by systematical studies of cycle-dependent large and small signal parameters and micro-morphologies. It was identified that mechanical stress induced microstructure damage beneath the electrodes renders the KNN ceramics to be vulnerable to bipolar cycling; while the mild fatigue behavior for CaZrO3-modified ones mainly originates from a thermally reversible domain wall pinning.open8
The interaction between maternal immune activation and alpha 7 nicotinic acetylcholine receptor in regulating behaviors in the offspring
Mutation of human chromosome 15q13.3 increases the risk for autism and schizophrenia. One of the noteworthy genes in 15q13.3 is CHRNA7, which encodes the nicotinic acetylcholine receptor alpha 7 subunit (α7nAChR) associated with schizophrenia in clinical studies and rodent models. This study investigates the role of α7nAChR in maternal immune activation (MIA) mice model, a murine model of environmental risk factor for autism and schizophrenia. We provided choline, a selective α7nAChR agonist among its several developmental roles, in the diet of C57BL/6N wild-type dams throughout the gestation and lactation period and induced MIA at mid-gestation. The adult offspring behavior and gene expression profile in the maternal splenic-placenta-fetal brain axis at mid-gestation were investigated. We found that choline supplementation prevented several MIA behavioral abnormalities in the wild-type offspring. Pro-inflammatory cytokine interleukin-6 (IL-6) and Chrna7 gene expression in the wild-type fetal brain were elevated by poly(I:C) injection and were suppressed by gestational choline supplementation. We further investigated the gene expression level of IL-6 in Chrna7 mutant mice. We found that the basal level of IL-6 was higher in Chrna7 mutant fetal brain, which suggests that α7nAChR may serve an anti-inflammatory role in the fetal brain during development. Lastly, we induced MIA in Chrna7+/− offspring. The Chrna7+/− offspring were more vulnerable to MIA, with increased behavioral abnormalities. Our study shows that α7nAChR modulates inflammatory response affecting the fetal brain and demonstrates its effects on offspring behavior development after maternal infection
CD9 Expression by Human Granulosa Cells and Platelets as a Predictor of Fertilization Success during IVF
Objective. To determine whether CD9 expression on human granulosa cells (GCs) and platelets could predict the success of conventional fertilization of human oocytes during in vitro fertilization (IVF). Methods. Thirty women undergoing IVF for nonmale factor infertility participated. Platelets from venous blood and GCs separated from retrieved oocytes were prepared for immunofluorescence. Flow cytometry quantified the percent of GCs expressing CD9, and CD9 surface density on GCs and platelets. Fertilization rate was determined for the total number of oocytes, and the number of mature oocytes per patient. Correlations tested for significant relationships (P < .05) between fertilization rates and CD9 expression. Results. CD9 surface density on human GCs is inversely correlated with fertilization rate of oocytes (P = .04), but the relationship was weak. Conclusion. More studies are needed to determine if CD9 expression on GCs would be useful for predicting conventional fertilization success during IVF
What lies beneath: A comparison of reading aloud in pure alexia and semantic dementia
Exaggerated effects of word length upon reading aloud performance define Pure Alexia, but
have also been observed in Semantic Dementia. Some researchers have proposed a readingspecific
account, whereby performance in these two disorders reflects the same cause:
impaired orthographic processing. In contrast, according to the primary systems view of
acquired reading disorders, Pure Alexia results from a basic visual processing deficit,
whereas degraded semantic knowledge undermines reading performance in Semantic
Dementia. To explore the source of reading deficits in these two disorders, we compared the
reading performance of 10 Pure Alexic and 10 Semantic Dementia patients, matched in terms of overall severity of reading deficit. The results revealed comparable frequency effects on
reading accuracy, but weaker effects of regularity in Pure Alexia than Semantic Dementia.
Analysis of error types revealed a higher rate of letter-based errors and a lower rate of
regularisation responses in Pure Alexia than Semantic Dementia. Error responses were most
often words in Pure Alexia but most often nonwords in Semantic Dementia. Although all
patients made some letter substitution errors, these were characterised by visual similarity in
Pure Alexia and phonological similarity in Semantic Dementia. Overall, the data indicate
that the reading deficits in Pure Alexia and Semantic Dementia arise from impairments of
visual processing and knowledge of word meaning, respectively. The locus and mechanisms
of these impairments are placed within the context of current connectionist models of
reading
Cross modal perception of body size in domestic dogs (Canis familiaris)
While the perception of size-related acoustic variation in animal vocalisations is well documented, little attention has been given to how this information might be integrated with corresponding visual information. Using a cross-modal design, we tested the ability of domestic dogs to match growls resynthesised to be typical of either a large or a small dog to size- matched models. Subjects looked at the size-matched model significantly more often and for a significantly longer duration than at the incorrect model, showing that they have the ability to relate information about body size from the acoustic domain to the appropriate visual category. Our study suggests that the perceptual and cognitive mechanisms at the basis of size assessment in mammals have a multisensory nature, and calls for further investigations of the multimodal processing of size information across animal species
Connectionist perspectives on language learning, representation and processing.
The field of formal linguistics was founded on the premise that language is mentally represented as a deterministic symbolic grammar. While this approach has captured many important characteristics of the world\u27s languages, it has also led to a tendency to focus theoretical questions on the correct formalization of grammatical rules while also de-emphasizing the role of learning and statistics in language development and processing. In this review we present a different approach to language research that has emerged from the parallel distributed processing or \u27connectionist\u27 enterprise. In the connectionist framework, mental operations are studied by simulating learning and processing within networks of artificial neurons. With that in mind, we discuss recent progress in connectionist models of auditory word recognition, reading, morphology, and syntactic processing. We argue that connectionist models can capture many important characteristics of how language is learned, represented, and processed, as well as providing new insights about the source of these behavioral patterns. Just as importantly, the networks naturally capture irregular (non-rule-like) patterns that are common within languages, something that has been difficult to reconcile with rule-based accounts of language without positing separate mechanisms for rules and exceptions
Development and evaluation of a diagnostic cytokine-release assay for Mycobacterium suricattae infection in meerkats (Suricata suricatta)
CITATION: Clarke, C., et al. 2017. Development and evaluation of a diagnostic cytokine-release assay for mycobacterium suricattae infection in meerkats (Suricata suricatta). BMC Veterinary Research, 13:2, doi:10.1186/s12917-016-0927-x.The original publication is available at http://bmcvetres.biomedcentral.comBackground: Sensitive diagnostic tools are necessary for the detection of Mycobacterium suricattae infection in meerkats (Suricata suricatta) in order to more clearly understand the epidemiology of tuberculosis and the
ecological consequences of the disease in this species. We therefore aimed to develop a cytokine release assay to measure antigen-specific cell-mediated immune responses of meerkats.
Results: Enzyme-linked immunosorbent assays (ELISAs) were evaluated for the detection of interferon-gamma
(IFN-γ) and IFN-γ inducible protein 10 (IP-10) in meerkat plasma. An IP-10 ELISA was selected to measure the release of this cytokine in whole blood in response to Bovigam® PC-HP Stimulating Antigen, a commercial peptide pool of M. bovis antigens. Using this protocol, captive meerkats with no known M. suricattae exposure (n = 10) were tested and results were used to define a diagnostic cut off value (mean plus 2 standard deviations). This IP-10 release
assay (IPRA) was then evaluated in free-living meerkats with known M. suricattae exposure, categorized as having either a low, moderate or high risk of infection with this pathogen. In each category, respectively, 24.7%, 27.3% and 82.4% of animals tested IPRA-positive. The odds of an animal testing positive was 14.0 times greater for animals
with a high risk of M. suricattae infection compared to animals with a low risk.
Conclusion: These results support the use of this assay as a measure of M. suricattae exposure in meerkat
populations. Ongoing longitudinal studies aim to evaluate the value of the IPRA as a diagnostic test of M. suricattae infection in individual animals.http://bmcvetres.biomedcentral.com/articles/10.1186/s12917-016-0927-xPublisher's versio
Design of a decision support system for multiobjective activity planning and programming using global bacteria optimization
The success of any project lies in a great manner on keeping costs in the estimated values, as well as meeting customer required due date. Therefore, there is a current need of developing an information system that facilitates the creation and managing of projects and their processes, including costing schemes, as well as monitoring an optimizing project’s makespan. In order to address this situation a user-friendly information system (IS) was developed. This IS includes an optimization module that reduces the project’s execution time, thus, minimizing costs and ultimately providing the manager with the right tools for the correct development of the project. Therefore, a better planning of activities in a reduced time is accomplished. In this way, the project manager is equipped with a decision support system (DSS) that allows a better decision making and, thanks to this performance optimization, a cost-effective solution can be delivered to the company. The optimization module is the main innovative component in this IS, considering that addresses the problem as a multiobjective one, considering at the same time makespan and cost. This module is based on global bacteria optimization (GBO). This becomes the most relevant improvement when compared to other ISs in the market
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