85 research outputs found

    Adapting to salinity: The effects of salinity on population structure and offspring survival in Lucania parva

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    Adaptation to salinity is an important driving force in the evolution in teleost fishes. Some speciose groups such as minnows and characids are found predominantly in fresh water, while other groups such as tunas and wrasses are found predominantly in marine habitats. Euryhaline groups, such as killifish, contain freshwater species, marine species, and species that can occur in fresh, brackish, and marine conditions. These groups are powerful systems for studying adaptation to salinity as they allow for the comparison of close relatives who differ in salinity tolerance. In chapter 1, I review the biology of Lucania killifish. Lucania contains three species, one of which is a freshwater species (L. goodei) and another of which is euryhaline (L. parva). A third species (L. interioris) is endemic to a small region in Mexico and is not considered in this thesis. Previous studies on L. goodei and L. parva suggest that salinity has dramatic effects on life-history, ecology, physiology, and genetic differentiation at the between-species level. Upon salinity transfer, the two species differ in gene expression in critical osmoregulatory genes. An examination of FST outliers suggests that the two species differ in many genes related to osmoregulation, but that they also possess high levels of differentiation between genes involved in reproduction and spermatogenesis. Within L. parva, preliminary work indicated that freshwater-saltwater population pairs also possessed elevated levels of differentiation in loci related to osmoregulation. In chapter 2, I used RAD-Seq data from 10 populations across Florida to examine the levels of population structure between freshwater and saltwater populations and the effects of distance on population-wide FST. Here, I found good evidence that differences in salinity increase FST beyond what would be expected from the effects of distance alone. In chapter 3, I describe a laboratory experiment that tests for both local adaptation and for maternal effects as a function of salinity. Early development is a critical life stage. From their earliest moments in life, embryos cannot regulate their ion and water levels because the physiological traits needed for active osmoregulation have not yet developed. Instead, embryos rely on the properties of the egg and maternal provisioning to maintain proper ion and water levels. Hence, this stage of development is ripe for maternal effects (either genetic or environmental) that influence offspring survival as a function of salinity. In chapter 3, I describe the results of an experiment where I performed within population crosses for a freshwater and a saltwater population from the Wakulla River drainage. In the experiment, I considered the effects of population of origin (fresh versus salt) and the effects of spawning salinity (the salinity in which spawning pairs were housed) and rearing salinity (the salinity in which eggs and fry were kept). Hence, the experiment allows me to examine the effects of population of origin and parental salinity environment on subsequent survival as a function of salinity. Here, I found little evidence for local adaptation as a function of salinity. Maternal effects were present, but the nature of the pattern did not suggest that they were adaptive. I suggest that other life-history stages such as over-winter survival, perhaps in the presence of intraspecific competition, should be assessed. My thesis indicates that there is evidence for heightened genetic divergence between freshwater and saltwater populations, yet we do not know precisely how these effects emerge. Salinity may affect multiple life-history stages (i.e., growth, survival to adulthood, over-winter survival) beyond the ones examined in this thesis. Salinity may also affect multiple aspects of ecology, including community composition (i.e., potential competitors, predators, and prey items), which may create parallel selection due to ecological demands

    Plasticity or local adaptation?: Survival of L. parva larvae in varying salinity

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    As environmental stressors continue to amplify, Lucania parva, or Rainwater Killifish, are expected to outlast other species in unpredictably fast changing environments, as they are unique in their ability to tolerate multiple salinities. The objective of this research is to understand what affects L. parva’s ability to tolerate salinity and discover the limitations the species might have to tolerating it. Understanding this fish’s biology will help with the conservation of aquatic ecosystems in Florida. Preliminary data and early trends suggest that during early larval stages, L. parva are plastic but the extent of their plasticity is limited as they cannot survive as well in extreme salinities

    Effects Of Home-based Electrical Exercise On Energy Index And Spasticity In Those With Spinal Cord Injury

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    Appropriate levels of physical activity are important to optimize well-being. Often, individuals with physical disabilities encounter barriers when attempting to engage in physical activity, such as lacking transportation or access to adapted activity equipment. Additionally, the COVID-19 pandemic disproportionately affected high-risk populations\u27 accessibility to physical activity, such as individuals with spinal cord injuries (SCI), which can greatly reduce mobility and increase disease susceptibility. Home-based exercise has been shown useful for improving flexibility and reducing spasticity. Additionally, the home-based exercise would remove transportation requirements and reduce the spread of disease, specifically COVID-19, during the pandemic. PURPOSE: The purpose of this study was to assess the chronic engagement of home-based electrical stimulation exercise (ESE) on energy index (EI) and spasticity in individuals with SCI. METHODS: 9 individuals with ASIA A or B SCI were recruited for this study. Participants were mailed exercise equipment (PowerDot). Participants completed a 5-day run-in period where they answered the brief assessment of mood (BAM) questionnaire and visual analog scale (10 cm) for spasticity via Qualtrics. Following this, participants engaged in neuromuscular electrical stimulation exercise (NMES) of the quadriceps and the hamstrings for 20 minutes each, totaling 40 minutes. This was completed Monday through Friday for three weeks or 15 total exercise sessions. Each night prior to bed, participants would complete the BAM and pain VAS. RESULTS: There was no main effect of time or spasticity on EI (F(33,225) = 0.73, p = 0.86, F(1,255) = 0.89, p = 0.35; respectively). CONCLUSION: Home-based ESE did not attenuate spasticity or increase EI in individuals with SCI. The modality of exercise may not be sufficient to drive beneficial alterations in either of the described variables

    Best Practices for Archival Term Positions

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    This document presents best practices for administrators, hiring managers, and supervisors to put into action when planning for and employing archival term positions. At the foundation of this document is the recognition that temporary labor is detrimental to employees, as well as to sustainable and holistic collection stewardship. This document is on a 5 year review cycle; it will be reviewed for potential updates in 2027

    Planning for Equity in a Local Context: Case Studies from the North Carolina chapter of the American Planning Association Contributors

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    Carolina Planning regularly publishes a feature highlighting projects from members of the North Carolina Chapter of the American Planning Association (NCAPA). This year’s submissions focus on initiatives that are addressing equity issues in North Carolina communities. From case studies discussing health impact assessments to articles highlighting the importance of using data to help inform equitable planning activities and funding, these writers provide valuable insights into the important role North Carolina planners play in shaping the futures of their communities. Includes: Acting For Equity (Introduction); Building Bridges to College and Career Success for Young Males of Color; Food Access; Transportation, Equity, and Access to Bus Transit; Health Impact Assessments and Planning: Bridging the Gap to Promote Health Equit

    Temperature dependence on the mass susceptibility and mass magnetization of superparamagnetic Mn–Zn–ferrite nanoparticles as contrast agents for magnetic imaging of oil and gas reservoirs

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    The mass susceptibility (χmass) and mass magnetization (Mmass) were determined for a series of ternary manganese and zinc ferrite nanoparticles (Mn–Zn ferrite NPs, MnxZn1−xFe2O4) with different Mn:Zn ratios (0.08 ≤ x ≤ 4.67), prepared by the thermal decomposition reaction of the appropriate metal acetylacetonate complexes, and for the binary homologs (MxFe3−xO4, where M = Mn or Zn). Alteration of the Mn:Zn ratio in Mn–Zn ferrite NPs does not significantly affect the particle size. At room temperature and low applied field strength the mass susceptibility increases sharply as the Mn:Zn ratio increases, but above a ratio of 0.4 further increase in the amount of manganese results in the mass susceptibility decreasing slightly, reaching a plateau above Mn:Zn ≈ 2. The compositional dependence of the mass magnetization shows less of a variation at room temperature and high applied fields. The temperature dependence of the mass magnetization of Mn–Zn ferrite NPs is significantly less for Mn-rich compositions making them more suitable for downhole imaging at higher temperatures (>100 °C). For non-shale reservoirs, replacement of nMag by Mn-rich Mn–Zn ferrites will allow for significant signal-to-noise enhancement of 6.5× over NP magnetite

    Development of mPing-based activation tags for crop insertional mutagenesis

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    Modern plant breeding increasingly relies on genomic information to guide crop improvement. Although some genes are characterized, additional tools are needed to effectively identify and characterize genes associated with crop traits. To address this need, the mPing element from rice was modified to serve as an activation tag to induce expression of nearby genes. Embedding promoter sequences in mPing resulted in a decrease in overall transposition rate; however, this effect was negated by using a hyperactive version of mPing called mmPing20. Transgenic soybean events carrying mPing-based activation tags and the appropriate transposase expression cassettes showed evidence of transposition. Expression analysis of a line that contained a heritable insertion of the mmPing20F activation tag indicated that the activation tag induced overexpression of the nearby soybean genes. This represents a significant advance in gene discovery technology as activation tags have the potential to induce more phenotypes than the original mPing element, improving the overall effectiveness of the mutagenesis system

    Metagenomic Analysis of Lysogeny in Tampa Bay: Implications for Prophage Gene Expression

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    Phage integrase genes often play a role in the establishment of lysogeny in temperate phage by catalyzing the integration of the phage into one of the host's replicons. To investigate temperate phage gene expression, an induced viral metagenome from Tampa Bay was sequenced by 454/Pyrosequencing. The sequencing yielded 294,068 reads with 6.6% identifiable. One hundred-three sequences had significant similarity to integrases by BLASTX analysis (e≤0.001). Four sequences with strongest amino-acid level similarity to integrases were selected and real-time PCR primers and probes were designed. Initial testing with microbial fraction DNA from Tampa Bay revealed 1.9×107, and 1300 gene copies of Vibrio-like integrase and Oceanicola-like integrase L−1 respectively. The other two integrases were not detected. The integrase assay was then tested on microbial fraction RNA extracted from 200 ml of Tampa Bay water sampled biweekly over a 12 month time series. Vibrio-like integrase gene expression was detected in three samples, with estimated copy numbers of 2.4-1280 L−1. Clostridium-like integrase gene expression was detected in 6 samples, with estimated copy numbers of 37 to 265 L−1. In all cases, detection of integrase gene expression corresponded to the occurrence of lysogeny as detected by prophage induction. Investigation of the environmental distribution of the two expressed integrases in the Global Ocean Survey Database found the Vibrio-like integrase was present in genome equivalents of 3.14% of microbial libraries and all four viral metagenomes. There were two similar genes in the library from British Columbia and one similar gene was detected in both the Gulf of Mexico and Sargasso Sea libraries. In contrast, in the Arctic library eleven similar genes were observed. The Clostridium-like integrase was less prevalent, being found in 0.58% of the microbial and none of the viral libraries. These results underscore the value of metagenomic data in discovering signature genes that play important roles in the environment through their expression, as demonstrated by integrases in lysogeny

    EIN ALTKROATISCHES GRABERFELD AUF DEM BERGE SPAS BEI KNIN

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    Autor objavljuje rezultate istraživanja starohrvatske nekropole na brdu Spasu kod Knina (otkriveno ukupno 228 grobova). Na temelju prikupljenih podataka tijekom višegodišnjih arheoloških istraživanja i sprovedene analize grobne arhitekture, pogrebnih običaja i grobnih nalaza utvrđeno je vrijeme ukopavanja na toj nekropoli i uputilo na mogući prostorni smještaj naselja kojemu je to groblje pripadalo. Završna razmatranja objelodanjenih grobnih nalaza otkrivaju niz novih spoznaja o gospoda.stvenim mogućnostima stanovništva, njihov kulturni i duhovni život u 9, 10. i 11. stoljeću. Osim starohrvatskih grobova na Spasu su otkopani i temeljni ostaci arhitekture, za koje se utvrdilo da pripadaju rimskom naselju, vjerojatno ostacima stare Ninie, odnosno Curcuma. Sve to popraćeno je obilnom dokumentacijskom građom i katalogom grobova.Westlich der Stadt Knin erstreckt sich der Berg Spas. Auf seinem siidlichen Teil erhebt sich die mittelalterliche Festung Knin, und an den nord lichen Teil schlieBt sich das Hochplateau des Berges Spas an, das im horizontalen Querschnitt cinE\u27 birnentormige Form hat. Spas ist anfangs des 18. lahrhunderts durch einen kiinstlichen Durchstich von der Festung getrennt worden. Im nordlichen, breitesten Teil des Plateaus wurde ein altkroatisches Graberfeld entdeckt, mit insgesamt 228 Grabern. Das erforsci1te Gebiet umfaBt etwa 1200 m2 Oberflache. Es wurden neben Grabern auch Fundamente von Bauwerken aus vorktoatischer Zeit gefunden, was bezeugt, daB es sich hier um eine komplexe archaologische Fundstatte handelt. Im ersten Teil seiner Abhandlung beschreibt. der Verfasser die Lage des Fundortes, seine strategische Bedeutung, und den geschichtlichen Ablauf der Forschungen an diesem Ort. AuBerdem erwahnt er unter anderen bedeutenden Funden auch die Entdeckung von Fundamenten von Bauwerken , fUr die er aufgrund von Fragmenten steinernen Skulpturen, Ziegeln und Fragmenten von KeramikgefaBen festelIen konnte, daB sie einer romisehen Ansiedlung angehorten. Durch Suchgrabung wurde festgestelIt, daB die Reste dieser Bauwerke sich auch auf den iibrigen Teil des Plateaus erstrecken, der bis jetzt nicht erforscht worden ist. Diese Entdeckungen, zusammen mit einem groBen, schon friiher untersuchten Graberfeld am ostlichen FuBe dieses Berges, genannt »Greblje«, sind ein starkes Argumentfi.ir die Annahme jener Forscher, die der Meinung sind, daB die alte, antike Stadtsiedlung Ninia, die von der Schriftstellern der Antike erwahnt wird , sich an der SteIle der heutigen Stadt Knin befunden hatte, beziehungsweise an der Stelle ihrer Festung und der Wallburg Spas. Im siidostlichen Teil des ausgegrabenen Graberfeldes hat man ziemlich groBe Schuttablagerungen gefunden, unter denen sich auch Stiicke von Mortel mit Farbresten befanden. An dieser Stelle und in ihrer unmittelbaren Nahe wurden einige steinerne Fragmente mit vorromanischer F1echtwerkplastik gefunden , die zu Kircheneinrichtungsgegenstanden aus dem 9. oder 10. lh. gehorten. Die erwahnten Funde weisen mjt Sicherheit darauf hin, daB sich an eben dieser Stelle, wo man den Schutt gefunden hat, eine altkroatische Kirche befunden hatte, der die gefundenen Fragmente angehorten. Da sich von diesem Kirchenbau auch nicht der allergeringste Rest einer Mauer erhalten hat, kann man nur schlieBen, daB die Kirche bis zu den Grundmauern zerstort worden war, und daB ihre Steine als Baurnaterial fUr die Mauern der nahegelegenen Festung verwendet wurden. Der zwei te Teil dieser Abhandlung enthalt den Katalog der Grabarchitektur und ihres lnventars. Hier findet man kurz gefaBt die wichtigsten Angaben i.iber jedes cinzeIne Grab und die osteologischen Funde, sowie eine genaue Beschreibung der Grabbeigaben. Der dritte Teil behandelt die allgemeinen Merkmale des Graberfeldes. Wegen der ungi.instigen Bodenstruktur, sowie der Fundamente der Bauwerke, besitzt das Graberfeld nicht die Merkmale von Reihengrabern, Die Graber sind sehr verschiedenartig orientiert, und liegen in allen Richtungen; der groBte Teil der Graber war trotzdem richtjg orientiert, in der Richtung Osten-Westen (103 Graber) . In den meisten Grabern befand sich nur ein Verstorbener, manchmal jedoch auch mehrere. Die gefundenen osteologischen Reste bestatigen, daB das Graberfeld einer Siedlung zugehorig; mit einer gleich groBen Anzahl von bestatteten Mannern , Frauern und Kindern. Die Graber waren meistens aus behauener Rauhwacke , aus unregelmaBigen Steinplatten oder aus Bruchsteinen gebaut. Die behauene Rauhwacke ftir die Graber stammte wahrscheinlich von den eingesttirzten Bauwerken in der nahen Umgebung. Weiterhin analysiert der Verfasser die Grabfunde, meistens Schmuck, und zwar Ohrringe und Ringe. Indem er die typologischen Besonderheiten der einzelnen Gegenstande genau beurteilt, und sie mit analogem Material aus den tibrigen altkroatischen und anderen Graberfeldern vergleicht, kommt er zu Schltissen ber die Herkunft und\u27 Datierung der Funde. Mehr Aufmerksamkeit schenkt der Verfasser den Ohrringen vom Typ mit drei Beeren und zwar deshalb, weil in letzter Zeit versucht wurde, fast alle entwickelteren Varianten dieses Typs, die in Grabern auf dem Gebiet des altkroatisches Staates gefunden worden waren, von allen tibrigen Ohrringen die ebenfalls auf diesem Gebiet gefunden wurden, zu trennen. [ndem er auf das Problem der Datierung und Herkunft der Ohrringe mit drei Beeren eingeht, versuchte der Verfasser aufgrund einer Reihe sicherer Tatsachen und Hinweise darauf hinzuweisen, daB dieser Typ von Ohrringen, beziehungsweise die starker entwickelten Varianten , nicht von den tibrigen Typenvarianten altkroatischer Ohrringe isoliert werden dtirfen, die auf dem Gebiet des dalmatinischen Kroatiens gefunden worden waren , und die meistens in die Zeit vom Beginn des 9. bis zum Ende des 11. lahrhunderts datiert werden. Er machte ebenfalls darauf aufmerksam, daB samtliche Typen von altkroatischen Ohrringen, und so auch die entwickelteren Varianten von Ohrringen mit drei Beeren, die aus Grabern des Mutterlandes stammen, aus einheimischen Goldschmiedewerkstatten stammen , und daB sie als Ganzes eine altkroatische Kulturgruppe bilden. AuBer seinen Vermutungen tiber die Lage und GroBe der Ansiedlung, zu der das Graberfeld auf dem Berge Spas gehorte, ist der Verfasser im Ganzen der Meinun~, daB das Graberfeld auf Spas dem Zeitraum des frtihfeudalen kroatischen Staates angehorte, d. h., daB das Graberfeld sei t dem Anfang des 9. Jahrhunderts bestanden hatte und kontinuierlich bis zum Ende des ll. Jahrhunderts fortdauerte
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