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An adaptive memory system should prioritize information surrounding a powerful learning event that may prove useful for predicting future meaningful events. The behavioral tagging hypothesis provides a mechanistic framework to interpret how weak experiences persist as durable memories through temporal association with a strong experience. Memories are composed of multiple elements, and different mnemonic aspects of the same experience may be uniquely affected by mechanisms that retroactively modulate a weakly encoded memory. Here, we investigated how emotional learning affects item and source memory for related events encoded close in time. Participants encoded trial-unique category exemplars before, during, and after Pavlovian fear conditioning. Selective retroactive enhancements in 24-h item memory were accompanied by a bias to misattribute items to the temporal context of fear conditioning. The strength of this source memory bias correlated with participants’ retroactive item memory enhancement, and source misattribution to the emotional context predicted whether items were remembered overall. In the framework of behavioral tagging: Memory attribution was biased to the temporal context of the stronger event that provided the putative source of memory stabilization for the weaker event. We additionally found that fear conditioning selectively and retroactively enhanced stimulus typicality ratings for related items, and that stimulus typicality also predicted overall item memory. Collectively, these results provide new evidence that items related to emotional learning are misattributed to the temporal context of the emotional event and judged to be more representative of their semantic category. Both processes may facilitate memory retrieval for related events encoded close in time.

Ecosystem transformation can be defined as the emergence of a self‐organizing, self‐sustaining, ecological or social–ecological system that deviates from prior ecosystem structure and function. These transformations are occurring across the globe; consequently, a static view of ecosystem processes is likely no longer sufficient for managing fish, wildlife, and other species. We present a framework that encompasses three strategies for fish and wildlife managers dealing with ecosystems vulnerable to transformation. Specifically, managers can resistchange and strive to maintain existing ecosystem composition, structure, and function; accepttransformation when it is not feasible to resist change or when changes are deemed socially acceptable; or directchange to a future ecosystem configuration that would yield desirable outcomes. Choice of a particular option likely hinges on anticipating future change, while also acknowledging that temporal and spatial scales, recent history and current state of the system, and magnitude of change can factor into the decision. This suite of management strategies can be implemented using a structured approach of learning and adapting as ecosystems change.

Advanced chemometric methods, such as fuzzy c-means (FCM), a fuzzy divisive hierarchical clustering algorithm (FDHC), and fuzzy divisive hierarchical associative-clustering (FDHAC), which offer the excellent possibility to associate each fuzzy partition of samples with a fuzzy set of characteristics (features), have been successfully applied in this study. FDHAC, a method that utilizes specific regions of chromatographic fingerprints or specific peaks as a fuzzy set of characteristics, was effectively applied to the characterization and classification of medicinal plant extracts according to their antioxidant capacities, using their chromatographic profiles monitored at 242, 260, 280, 320, 340, and 380 nm viaHPLC with a multistep isocratic and gradient elution system and diode array detection (HPLC-DAD). What is quite new is the partitioning of the chromatographic retention time ranges and peaks (markers) and their association with different plant extract samples with high, moderate or low antioxidant capacity. Furthermore, the degrees of membership of fingerprints (fuzzy markers) are highly relevant with respect to the (dis)similarity of samples because they indicate both the positions and degrees of association of chromatographic peaks from different classes or individual samples. The obtained results clearly demonstrate the efficiency and information power of these advanced fuzzy methods for medicinal plant characterization and authentication, and this study generates the premise for a new chemometrics approach with high-impact for use in analytical chemistry and other fields.

Rapid urbanization will increase the number of novel stream ecosystems in the Southeastern United States. The green sunfish (Lepomis cyanellus) is a globally widespread, invasive species that is particularly well-adapted to urban stream conditions. The trophic ecology of green sunfish is understudied, especially in the novel ecosystems where they appear to thrive. We assessed predation by green sunfish in the food web of a heavily engineered and restored urban stream in Raleigh, North Carolina. We sampled fish species composition, size structure, abundance, the benthic macroinvertebrate assemblage, and fish diets during two seasons. Green sunfish was the sole species inhabiting the study stream, with the exception of a single goldfish. The population size structure indicated potential overcrowding in our study ecosystem. Chironomidae was the most common taxa in both the benthic macroinvertebrate assemblage and in fish diets during the summer. We observed a seasonal shift in diets to lesser prey-specific abundance of Chironomidae and a greater overall abundance of terrestrial prey from summer to winter. Green sunfish can persist in small restored urban streams of the Southeast US where virtually no other fish occur, and they utilize benthic invertebrates and terrestrial prey as resources.

High-spatial-resolution diffusion-tensor images obtained at ultra-high-field-strength allow an accurate and reproducible quantification of structural organization of skeletal muscle fibers.

With the movement towards bundled payments, stakeholders should know the true cost of the care they deliver. Time-driven activity-based costing (TDABC) can be used to estimate costs for each episode of care. In this analysis, TDABC is used to both estimate the costs of anesthesia care and identify the primary drivers of those costs of 11 common oncologic outpatient surgical procedures.

Despite potential to structure ecosystem food webs through top-down effects, the trophic interactions of the American Eel Anguilla rostrataremain largely understudied. All previous research on the trophic ecology of American Eel in inland aquatic ecosystems has been conducted in temperate continental regions of the species' range. These studies have led to a paradigm that American Eel is a nocturnally active benthic predator, which most commonly consumes benthic invertebrates. Tropical island streams and rivers have habitats and communities that are distinct from temperate counterparts, but comprise a large portion of the adult habitat in the American Eel's range. We documented a previously undescribed diurnal feeding behavior by American Eel in a Caribbean river and demonstrate that this behavior, and a shift toward more frequent daytime feeding, is linked to periodic mass migrations of postlarvae of amphidromous fish taxa, including the Sicydiine goby Sicydiumspp. Our findings indicate that periodic mass migrations of amphidromous postlarvae could function as a potentially important food source for American Eel in tropical regions of its distribution, despite the intermittence of availability. Furthermore, this suggests that the American Eel plays an important role in the structure of tropical lotic food webs through top-down effects that are potentially augmented by instream barriers.

The value and impact of process improvement initiatives are difficult to quantify. We describe the use of time-driven activity-based costing (TDABC) in a clinical setting to quantify the value of process improvements in terms of cost, time and personnel resources.

The structural, electrical and dielectric properties of a series of Ni1–xCexAl2O4 (x = 0.0, 0.2, 0.4, 0.6, 0.8) compositions have been studied. The samples were prepared by a novel glycine–nitrate combustion synthesis route. The substitution of Ce4+ for Ni2+ results in an increase in the lattice constant owing to the larger size of the substituent. The X-ray density increases with increasing Ce4+ content. The IR spectra show two fundamental absorption bands, which are shifted gradually towards higher energy with the addition of Ce4+. The UV–visible spectra confirm the preference of Ni2+ for the octahedral site. The dc electrical conductivity increases with increasing temperature due to the mobility of thermally activated charge carriers. Due to the electrostatic screening effect of B-site cations, the conductivity decreases with increasing Ce4+ content. The dielectric constant and loss tangent of the synthesized compounds show the normal behavior of spinel compounds. The ac electrical conductivity increases with increasing applied frequency and decreases with increasing Ce4+ substitution. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The Conference of Parties (COP) to the Convention on Biological Diversity (CBD) has recognised the currently existing taxonomic impediment to ensure the conservation and management of the world's biodiversity. In response, COP has formulated the concept of a Global Taxonomy Initiative (GTI) to promote a concerted effort among international funding agencies, national and sub­national governments, and non­governmental bodies. The GTI Africa Regional Workshop was held at the Kirstenbosch National Botanical Garden, Claremont, Cape Town, South Africa, from 27 February to 1 March 2001. The Workshop was attended by a total of 43 delegates, representing 32 countries (23 African) and 36 institutions or organisations. The Kirstenbosch Declarationwas compiled during the Workshop and summarises the major decisions and proposals made by the delegates at the Workshop. A Final Report summarising the discussions and decisions from the GTI Africa Regional Workshop is being prepared and will be distributed to all interested parties. A taxonomic needs assessment for Africa has been conducted as part of this project. The results from this first ever comprehensive taxonomic needs assessment covering plants, animals and micro­organisms for the African continent as a unit, are reported on here and forms an important part of the Final Report. The needs assessment highlights the prominent taxonomic impediment currently existing in the continent. Taxonomic capacity building is urgently needed in Africa; therefore, African taxonomic institutions can benefit immensely from the Global Taxonomy Initiative.

Mitochondrial diseases are genetic disorders that lead to impaired mitochondrial function, resulting in exercise intolerance and muscle weakness. In patients, muscle fatigue due to defects in mitochondrial oxidative capacities commonly precedes muscle weakness. In mice, deletion of the fast-twitch skeletal muscle-specific Tfam gene (Tfam KO) leads to a deficit in respiratory chain activity, severe muscle weakness and early death. Here, we performed a time-course study of mitochondrial and muscular dysfunctions in 11- and 14-week-old Tfam KO mice, i.e. before and when mice are about to enter the terminal stage, respectively. Although force in the unfatigued state was reduced in Tfam KO mice compared to control littermates (wild type) only at 14 weeks, during repeated submaximal contractions fatigue was faster at both ages. During fatiguing stimulation, total phosphocreatine breakdown was larger in Tfam KO muscle than in wild-type muscle at both ages, whereas phosphocreatine consumption was faster only at 14 weeks. In conclusion, the Tfam KO mouse model represents a reliable model of lethal mitochondrial myopathy in which impaired mitochondrial energy production and premature fatigue occur before muscle weakness and early death.

During aging, the epidermis and dermis become thin and an efficient anti‐aging product should be able to stimulate the metabolism of senescent fibroblast and keratinocytes, in order to increase the quantity of extra‐cellular matrix components such as collagen and glycosaminoglycans. A study performed in parallel on an in vitro skin equivalent model, and in vivo, with human volunteers, demonstrated the efficacy of one specific soya biopeptide for anti‐aging properties.

Abstract: The development of new cosmetic formulations requires precise assessment of their safety and efficacy. Today, legislation demands quality control combined with severe safety measures, as well as a limited use of animals for such testing (European Community directive 93/35/EEC). Consequently, safety assessment protocols are oriented towards in vivo tests on human volunteers and in vitro alternative methods to animal use, especially tissue engineered skin substitutes. In this paper, dermal and skin equivalents developed in the laboratory are described. The applications of reconstructed epidermis and skin substitutes for pharmaco-toxicological trials are also discussed. These tissue models have been shown to be very useful tools to assess cutaneous irritation, phototoxicity, photoprotection and to perform efficacy tests of cosmetic molecules and finished products. In conclusion, the authors are confident that these in vitro models can contribute to reduce animal use for routine toxicity testing.

In the collaborative exercise GEDNAP IV one EDTA blood sample (2 ml) and 5 bloodstains (0.5 ml on cotton) were investigated and in GEDNAP V, a total of 8 bloodstains (0.5 m1 on cotton), including 2 mixed bloodstains. DNA typing was carried out using the RFLP systems YNH24/Hinf I and MS43a/Hinf I and the PCR systems HLA DQa, D1S80, ApoB and YNZ22. In both exercises approximately 20 laboratories obtained results using the RFLP systems. Of the PCR systems, DIS80 was the most commonly used (14 labs in GEDNAP IV; 18 labs in GEDNAP V). The interlaboratory standard deviation for YNH24 in both exercises was approx. 0.6%, for MS43a 0.7–2.2% (GEDNAP IV) and 0.4–1.4% (GEDNAP V), depending on the fragment size. The fragment size calculation performed in each laboratory yielded a standard deviation twice that obtained when the fragment size calculation was performed centrally (IfR, Münster). In GEDNAP III, a system-specific corridor was developed to define the limits of deviation; this was modified for the present study by combining the fragment size ranges of YNH24 and MS43a. In both studies a subgroup of laboratories was involved in preliminary exercises using three PCR VNTRs and the system HLA DQa. Owing to the substantial variation in experience of the participating laboratories with PCR typing the results obtained in these two studies do not fulfil the basic quality criteria of the GEDNAP studies.

Phototoxicity inducing in vivophotoirritation, a reversible inflammatory reaction of the skin after chemical contact and UVA radiation exposure, is increasingly observed as a side effect associated with the use of both cosmetics and systemic drugs. In order to systematically screen for the phototoxic potential of new compounds, we propose two three‐dimensional models suitable for in vitrotesting: a dermal equivalent (DE) and a skin equivalent (SE) model. The DE model includes a collagen‐glycosaminoglycans‐chitosan porous matrix populated by normal human fibroblasts. The SE model is made by seeding normal human keratinocytes onto the DE, leading to a fully differentiated epidermis. The objectives of this pilot study are: 1) to compare the deleterious effects of UVA radiation on the two models and 2) to evaluate to what extent the in vitroresults can predict the in vivophototoxicity caused by well‐known photoirritant compounds, included in the COLIPA validation phototoxicity reference chemical list. Dilutions of thiourea, sulisobenzone, promethazine, chlorpromazine and tetracycline were applied (20 μl) onto DEs and SEs (n= 6) and incubated for 1 h (or 15 h) at 37°C. Irradiated samples received 3 J/cm2UVA. The 24 h post‐irradiation residual cellular viability was measured using the MTT test on treated and untreated tissues and IL‐1α release measurement in collected SE culture media. A concordance in terms of photoirritant/non‐photoirritant was obtained between the in vivodata and the in vitroresults, suggesting that the DE and the SE models could be integrated, after a complete validation study, into a protocol for in vitrotesting of the photoirritant potential of new molecules.

The legal procedure for evaluating the toxicity of cosmetic, household, chemical and pharmaceutical products is still the irritancy Draize test on rabbits. Various irritation tests are currently being developed as alternatives toin vivo animal testing. Ourin vitro model system is composed of 24 equivalent dermis (ED) comprising a chitosan-cross-linked collagen-glycosaminoglycan matrix populated by foreskin fibroblasts. In evaluating this system for irritancy testing, three different measures of toxicity were used: MTT (dimethylthiazol diphenyltetrazolium bromide) reduction, and lactate dehydrogenase and interleukin-6 release. The experiments described herein represent a preliminary evaluation to determine the usefulness and predictive value of our 24 ED kit as an alternative method for the prediction of human dermal reaction, versus three chemical products: cadmium chloride, lauryl sulfate, and benzalkonium chloride. Preliminary results suggest that the ED may be a usefulin vitro model for the prediction of cutaneous and ocular toxicity and allow the development of a 24-skin-equivalent kit realized by seeding human normal keratinocytes onto the equivalent dermis.

AbstractSt. Helen's Island, the site of Trichoptera studies in 1964 and 1965, is described. The Trichoptera encountered are listed, and taxonomic notes given where appropriate. Catches from a light-trap operated nightly in each year provide information for the different species concerning: relative abundance, frequency and seasonal range of occurrence, pest status, and sex ratio. Of the 99 species recorded, eight were classified as pests (causing a nuisance at light), six having this status in both years; together these eight species made up 87.6% of the seasonal total in 1965. Between late May and late September 1965, when large numbers arrived at light (median nightly catch ca. 3 × 103), a nuisance occurred on about one third of nights. Excluding Psychomyia flavida, of which only females were taken at light, most species showed a slight preponderance of males, but sex ratios varied widely according to species, year and night of capture.