84 research outputs found
Genomics clarifies taxonomic boundaries in a difficult species complex.
Efforts to taxonomically delineate species are often confounded with conflicting information and subjective interpretation. Advances in genomic methods have resulted in a new approach to taxonomic identification that stands to greatly reduce much of this conflict. This approach is ideal for species complexes, where divergence times are recent (evolutionarily) and lineages less well defined. The California Roach/Hitch fish species complex is an excellent example, experiencing a convoluted geologic history, diverse habitats, conflicting species designations and potential admixture between species. Here we use this fish complex to illustrate how genomics can be used to better clarify and assign taxonomic categories. We performed restriction-site associated DNA (RAD) sequencing on 255 Roach and Hitch samples collected throughout California to discover and genotype thousands of single nucleotide polymorphism (SNPs). Data were then used in hierarchical principal component, admixture, and FST analyses to provide results that consistently resolved a number of ambiguities and provided novel insights across a range of taxonomic levels. At the highest level, our results show that the CA Roach/Hitch complex should be considered five species split into two genera (4 + 1) as opposed to two species from distinct genera (1 +1). Subsequent levels revealed multiple subspecies and distinct population segments within identified species. At the lowest level, our results indicate Roach from a large coastal river are not native but instead introduced from a nearby river. Overall, this study provides a clear demonstration of the power of genomic methods for informing taxonomy and serves as a model for future studies wishing to decipher difficult species questions. By allowing for systematic identification across multiple scales, taxonomic structure can then be tied to historical and contemporary ecological, geographic or anthropogenic factors
State of Play: A Citation Network Analysis of Healthcare Gamification Studies
Researchers and practitioners alike increasingly recognize gamification as a potential tool to evoke desired behaviours in patients, healthcare professionals, and healthy end-users aiming to live a healthier lifestyle. Thus, the number of scientific publications in healthcare gamification is rapidly increasing and due to the interdisciplinary nature of the research field, knowledge about this topic is being scattered over many research communities. Building on a large number of articles on healthcare gamification and utilizing citation network analysis, this study sheds fur-ther light on the extant knowledge on healthcare gamification. Based on our approach, we were able to (1) evaluate essential articles and authors covering the topic, (2) analyse the recent de-velopment of research on healthcare gamification, and (3) identify past research foci and knowledge gaps in our knowledge on healthcare gamification. By doing so, we call for further research on healthcare gamification and provide researchers with potential avenues for future research projects
Towards green chemicals and edible coatings from barks and peels with near critical extraction of suberin
peer reviewedDue to their complex structures, industrial suberoligneous by-products such as barks and peels remain poorly exploited. In this study, we demonstrated the efficient extraction of suberin from barks (11.3%) and peels (20.85%) via supercritical and near-supercritical transesterification without the need for catalysts.
When applied in non-isocyanate polyurethane (NIPU) foams, suberinic extracts allowed the increase of the biomass content by up to 20% and facilitated the foaming process by improving pre-curing viscosity. When sprayed on fruits, the suberinic extracts effectively reduced the water loss rate by 25%, extending the shelf-life of the produce. A life cycle analysis for the latter application confirmed the competitive potential of our process against plastic sealing. This work uncovers the potential of suberoligneous biomass (SBM) to provide sustainable solutions to emerging societal challenges
Early Marine Migration Patterns of Wild Coastal Cutthroat Trout (Oncorhynchus clarki clarki), Steelhead Trout (Oncorhynchus mykiss), and Their Hybrids
Hybridization between coastal cutthroat trout (Oncorhynchus clarki clarki) and steelhead or rainbow trout (Oncorhynchus mykiss) has been documented in several streams along the North American west coast. The two species occupy similar freshwater habitats but the anadromous forms differ greatly in the duration of marine residence and migration patterns at sea. Intermediate morphological, physiological, and performance traits have been reported for hybrids but little information has been published comparing the behavior of hybrids to the pure species.This study used acoustic telemetry to record the movements of 52 cutthroat, 42 steelhead x cutthroat hybrids, and 89 steelhead smolts, all wild, that migrated from Big Beef Creek into Hood Canal (Puget Sound, Washington). Various spatial and temporal metrics were used to compare the behavior of the pure species to their hybrids. Median hybrid residence time, estuary time, and tortuosity values were intermediate compared to the pure species. The median total track distance was greater for hybrids than for either cutthroat or steelhead. At the end of each track, most steelhead (80%) were located near or north of the Hood Canal, as expected for this seaward migrating species, whereas most cutthroat (89%) were within 8 kilometers of the estuary. Most hybrids (70%) were detected leaving Hood Canal, though a substantial percentage (20%) remained near the Big Beef Creek estuary. More hybrids (7.5%) than pure cutthroat (4.5%) or steelhead (0.0%) were last detected in the southern reaches of Hood Canal.Given the similarity in freshwater ecology between the species, differences in marine ecology may play an important role in maintaining species integrity in areas of sympatry
Determination of nutrient salts by automatic methods both in seawater and brackish water: the phosphate blank
9 páginas, 2 tablas, 2 figurasThe main inconvenience in determining nutrients in seawater by automatic methods is simply solved:
the preparation of a suitable blank which corrects the effect of the refractive index change on the recorded
signal. Two procedures are proposed, one physical (a simple equation to estimate the effect) and the other
chemical (removal of the dissolved phosphorus with ferric hydroxide).Support for this work came from CICYT (MAR88-0245 project) and
Conselleria de Pesca de la Xunta de GaliciaPeer reviewe
Diversification, speciation, and phylogeography of freshwater sculpins (Cottus, Cottopsis) in California
Freshwater systems across North America and Eurasia are home to inconspicuous species of fish known as sculpins (genus Cottus). As generally small, benthic species, sculpins have largely been ignored by humans. One lineage in particular, Cottopsis, is endemic to the west coast of North America and inhabits diverse geographic areas and ecological conditions. Such complexity is the perfect setting for understanding issues related to speciation, divergence, population structure, gene flow, and phylogeography of freshwater fishes. Comprehensive phylogenetic work using multiple nuclear and mitochondrial markers generated species trees and delimitations which varied slightly by technique and statistical approach, but which revealed a number of cryptic lineages and relationships within the clade. Three species groups in particular showed remarkable variation in California, riffle (C. gulosus) and Pit (C. pitensis) sculpin, and prickly sculpin (C. asper). Following an extensive distributional sampling, a number of phylogeographic breaks, cryptic lineages, and speciation mechanisms were discovered. Within C. gulosus and C. pitensis, the Sacramento River proved to be distinctive showing potential historical hybridization, complete C. pitensis mitochondrial introgression, and restricted contemporary population structure. Consistent with other studies, a phylogeographic break along the Sacramento/San Joaquin River Delta led to the prospective divergence of C. pitensis into the Sacramento/Pit River basin and C. gulosus into the San Joaquin River basin; with different measures of isolation by distance and intra-population structure. A similar break and population structure was seen in inland C. asper populations. Estimated to have diverged from amphidromous coastal populations 110,000 years ago, inland C. asper represent incipient speciation, as evident by poor phylogenetic distinctiveness. Low measures of gene flow and hybridization in the narrow connective corridor between coastal and inland populations, along with no sign of physical barriers suggest inland C. asper are diverging by way of parapatric speciation. A novel lineage of C. asper in Clear Lake is also well-supported, originating from coastal, not inland populations. Overall, results clearly signify sculpin are a complex species group, with structure reflective of their historical hydrology, and worthy of intensive conservation and management strategies
THE PHENOMENOLOGY OF DISTRESS IN THE ABSENCE OF ELECTRONIC DEVICES AND ITS RELATIONSHIP WITH OTHER TYPES OF DISTRESS
The recent surge in the availability of personal electronics is enabling more people to use them in their daily lives. Yet, many people experience some distress associated with using electronics, especially if they are unable to access or use their devices. This distress has not been adequately examined in previous studies and there is no existing research concerning whether distress without electronics (DWE) is related to other mental health issues. The objective of this study was to investigate the phenomenology of DWE within a non-clinical sample, as well as its association with other types of distress. A sample of 236 students completed a survey including the Sheehan Disability Scale modified to address DWE, Generalized Anxiety Disorder 7, Body Sensations Questionnaire, Agoraphobic Cognitions Questionnaire, Obsessive-Compulsive Inventory-Revised, Anxiety Sensitivity Inventory, UCLA Loneliness Scale, and the Distress without Electronics Questionnaire, which was developed for this study. The majority of participants reported experiencing some symptoms of DWE, especially when unable to use phones and computers. DWE was positively correlated with generalized anxiety, agoraphobic, and obsessive-compulsive symptoms, anxiety sensitivity, and loneliness. Implications and directions for future research are discussed
Challenges to the conceptualization and measurement of religiosity and spirituality in mental health research.
Investigating religiosity and spirituality may help to further elucidate how individuals\u27 worldviews influence their attitudes, behavior, and overall well-being. However, inconsistencies in how these constructs are conceptualized and measured may undercut the potential value of religiosity and spirituality research. Results from a survey of undergraduate students suggest that laypeople define spirituality as independent from social influence and that few people associate religiosity with negative terms. A content analysis of spirituality measures indicates that spirituality measures contain items that do not directly measure the strength of spirituality. Implications and suggestions for future research are discussed
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