Temporal and spatial variation of broadleaf forest flammability in boreal Alaska

Thesis (M.S.) University of Alaska Fairbanks, 2018The boreal forest is a carbon reservoir containing roughly 40% of the world's reactive soil carbon, which is mainly cycled by wildland fires. Climate warming in boreal Alaska has changed the wildfire regime such that an increase in broadleaf forest relative to conifer forest is likely, which may reduce landscape flammability. However, the current and future flammability of broadleaf forest in a warming climate is not well understood. We used pre-fire and post-fire geospatial data to investigate the flammability of upland boreal forest patches in Interior Alaska in relation to summer weather conditions. Our objectives were to assess burning of broadleaf forest patches during "Normal" vs. "Large Fire Years", by week within a fire season, and by topographic position. Using 30-meter land-cover and fire-severity grids, we estimated the flammability of upland broadleaf forest patches during Large and Normal Fire Years. We then tested for topographic effects using a solar radiation index to eliminate potential deviations within the vegetation. Finally, Moderate Resolution Imaging Spectroradiometer (MODIS) hotspots were used to track the spatial extent of burns during the fire season by examining the periods of fire activity and intensity. Flammability of broadleaf forest patches varied both in time and space. Even during Normal Fire Years, broadleaf forest patches exhibited substantial flammability, with a mean of over 50% patch area burned. Patch flammability was significantly higher during Large Fire Years. Burning of broadleaf patches varied with topographic position and correlated with potential insolation. Broadleaf forest patches burned most frequently in late June-early July. Contrary to "conventional wisdom", broadleaf forest patches in boreal Alaska are susceptible to burning even during Normal Fire Years. With climate warming, the flammability of broadleaf forest is likely to increase due to more extreme fire weather events. Thus, although the frequency of broadleaf forest patches on the landscape is likely to increase with more frequent and severe wildfires, their effectiveness as a fire break may decrease in the future.National Science Foundation Bonanza Creek Long-Term Ecological Research Progra

Comparative metal oxide nanoparticle toxicity using embryonic zebrafish

AbstractEngineered metal oxide nanoparticles (MO NPs) are finding increasing utility in the medical field as anticancer agents. Before validation of in vivo anticancer efficacy can occur, a better understanding of whole-animal toxicity is required. We compared the toxicity of seven widely used semiconductor MO NPs made from zinc oxide (ZnO), titanium dioxide, cerium dioxide and tin dioxide prepared in pure water and in synthetic seawater using a five-day embryonic zebrafish assay. We hypothesized that the toxicity of these engineered MO NPs would depend on physicochemical properties. Significant agglomeration of MO NPs in aqueous solutions is common making it challenging to associate NP characteristics such as size and charge with toxicity. However, data from our agglomerated MO NPs suggests that the elemental composition and dissolution potential are major drivers of toxicity. Only ZnO caused significant adverse effects of all MO particles tested, and only when prepared in pure water (point estimate median lethal concentration=3.5–9.1mg/L). This toxicity was life stage dependent. The 24h toxicity increased greatly (∼22.7 fold) when zebrafish exposures started at the larval life stage compared to the 24h toxicity following embryonic exposure. Investigation into whether dissolution could account for ZnO toxicity revealed high levels of zinc ion (40–89% of total sample) were generated. Exposure to zinc ion equivalents revealed dissolved Zn2+ may be a major contributor to ZnO toxicity

Using 4-D imaging of the zebrafish model to observe pharmacodynamics of a therapeutic drug on glioblastoma

Glioblastoma Multiform • Type of aggressive brain cancer • Five year survival rate of 4.70% • Not often detected until it’s in the later stages when the symptoms appear • Surgery is not an effective option due to invasion and proliferation of glioblastoma cells outside of the tumor mass before and after surgery Why the Zebrafish Model? • Transparent body • Organism size • Short assay period • Little media required • No adaptive immune system for 28 dpf • Vertebrate anatomy and brain microenvironmen

Microbiota alter metabolism and mediate neurodevelopmental toxicity of 17β-estradiol

Estrogenic chemicals are widespread environmental contaminants associated with diverse health and ecological effects. During early vertebrate development, estrogen receptor signaling is critical for many different physiologic responses, including nervous system function. Recently, host-associated microbiota have been shown to influence neurodevelopment. Here, we hypothesized that microbiota may biotransform exogenous 17-βestradiol (E2) and modify E2 effects on swimming behavior. Colonized zebrafish were continuously exposed to non-teratogenic E2 concentrations from 1 to 10 days post-fertilization (dpf). Changes in microbial composition and predicted metagenomic function were evaluated. Locomotor activity was assessed in colonized and axenic (microbe-free) zebrafish exposed to E2 using a standard light/dark behavioral assay. Zebrafish tissue was collected for chemistry analyses. While E2 exposure did not alter microbial composition or putative function, colonized E2-exposed larvae showed reduced locomotor activity in the light, in contrast to axenic E2-exposed larvae, which exhibited normal behavior. Measured E2 concentrations were significantly higher in axenic relative to colonized zebrafish. Integrated peak area for putative sulfonated and glucuronidated E2 metabolites showed a similar trend. These data demonstrate that E2 locomotor effects in the light phase are dependent on the presence of microbiota and suggest that microbiota influence chemical E2 toxicokinetics. More broadly, this work supports the concept that microbial colonization status may influence chemical toxicity

043. John 15:17-21

Chapel Sermon by Neil Wehmas from John 15:17-21 on Tuesday, December 27, 2011

ERAS-protokollan implementointi verisuonikirurgisen potilaan hoitotyöhön

ERAS-protokollalla (Enhanced recovery after surgery) kuvataan nopeutettua leikkauksen jälkeistä toipumista. Tämän protokollan tavoitteena on potilaslähtöiseen ja tutkimustietoon perustuva tapa minimoida potilaan leikkauksen aikaista stressireaktiota, parantaa fysiologisia toimintoja sekä nopeuttaa toipumisprosessia leikkauksen jälkeen. Potilaan osastolla vietetty aika tällöin lyhenee, jolloin myös yhteiskunnalliset kustannukset pienenevät. ERAS-protokolla kehitettiin alun perin suolistokirurgisille potilaille ja on jo hyödynnetty myös muussa kirurgiassa. ERAS-protokollan hyötyä verisuonikirurgisten potilaiden hoitamisessa on tutkittu vasta vähäisesti, mutta sen hyödyntämistä tähänkin potilasryhmään on jo suunniteltu. Verisuonikirurgiset potilaat aiheuttavat omat haasteensa ERAS-protokollan toteuttamiselle perioperatiivisessa hoitotyössä. Potilaat ovat iäkkäitä, fyysisesti hauraita ja heillä on monia liitännäissairauksia, minkä vuoksi heitä terveydenhuollossa hoidetaan jo laajasti. Näyttöön perustuva ja korkealaatuinen hoito kuitenkin sopii implementoitavaksi myös verisuonikirurgisen potilaan hoitotyöhön. Tämän opinnäytetyön tarkoituksena oli selvittää, mitkä keinot edesauttavat ERAS-protokollan implementointia verisuonikirurgisen potilaan hoitotyöhön. Tavoitteena oli tuottaa toimintasuosituksia ERAS-protokollan jalkauttamisesta verisuonikirurgisen potilaan hoitotyöhön sekä luoda ERAS-protokollan perioperatiivinen check-lista jalkauttamisen tueksi. Systemaattinen kirjallisuushaku tehtiin CINAHL Complete, Medline ja Medic-tietokantoihin. Alkuperäistutkimukset valittiin etukäteen määriteltyjen sisäänotto- ja poissulkukriteereiden mukaisesti. Laadunarvioinnin jälkeen katsaukseen valittiin seitsemäntoista kansainvälisesti tehtyä alkuperäistutkimusta. Kerätyille tuloksille tehtiin induktiivinen sisällönanalyysi. Tuloksista tunnistettiin ERAS-protokollan implementointia helpottavia menetelmiä sekä esteitä implementoinnille. Nämä tulokset sopeutettiin verisuonikirurgisen potilaan hoitotyöhön ja niiden perusteella luotiin ohjeistus sekä check-lista perioperatiiviseen hoitotyöhön.ERAS (Enhanced Recovery After Surgery) is a comprehensive perioperative protocol designed to expedite the postoperative recovery process following major surgical procedures. This protocol is founded on a primary objective of minimizing postoperative complications and reducing the length of hospital stays, thus reducing the escalating healthcare costs. The implementation of the ERAS protocol in the context of vascular surgery patients presents a unique set of challenges in perioperative care. Vascular surgery patients are often advanced in age and suffer from multiple comorbidities and frailty, rendering them a distinct patient group within the healthcare system. Regrettably, the formalized guidelines for the implementation of ERAS within the domain of vascular surgery are currently lacking. This thesis aimed to address this gap by identifying tools to facilitate the integration of the ERAS protocol into the care of vascular surgery patients. The primary objectives were to generate recommendations for the adoption of the ERAS protocol in the management of patients undergoing vascular surgery and to devise a perioperative checklist to aid in the implementation of this protocol. To achieve these goals, a systematic literature search was conducted, utilizing CINAHL Complete, Medline, and Medic databases. The selection of original studies was conducted in adherence to predetermined inclusion and exclusion criteria, ultimately resulting in the identification of seventeen internationally published original studies. These selected studies underwent qualitative review, and an inductive content analysis was performed on the collected data. The findings from these studies were leveraged to discern methods that could facilitate the implementation of the ERAS protocol, as well as to identify barriers to implementation. These insights were then adapted to the specific context of vascular surgery patients, culminating in the formulation of a comprehensive guideline and checklist for perioperative care. As a prospective follow-up to this study, it is conceivable to conduct a survey aimed at assessing the duration of hospitalization for vascular surgery patients subsequent to the implementation of the ERAS protocol

Toxicogenomic analysis of >25-year-old archival tissue samples indicate metal sulfate mode of action and potency

Poster for SOT on Mar. 19-23, 2023 in Nashville, TN Science Inventory, CCTE products: https://cfpub.epa.gov/si/si_public_search_results.cfm?advSearch=true&showCriteria=2&keyword=CCTE&TIMSType=&TIMSSubTypeID=&epaNumber=&ombCat=Any&dateBeginPublishedPresented=07/01/2017&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&DEID=&personName=&personID=&role=Any&journalName=&journalID=&publisherName=&publisherID=&sortBy=pubDate&count=25</p