1,231 research outputs found
Planting the Seeds to Examine Food Security Challenges in the Alaska Food-Energy-Water Nexus
What is the Food-Energy-Water Nexus? It is the relationship between the energy that is used to clean and treat water and to grow food. It is also the recognition that it takes water to grow food and produce electrical power, and that it takes food to power us all to keep these systems running. This set of relationships can be considered at different scales including the "micro" that is most characteristic of small island communities in Alaska. This presentation was delivered at the Alaska Food Policy Council 2019 Festival and Conference.NSF Chemical, Bioengineering, Environmental and Transport Systems - INFEWS program (# 1740075)
University of Calgary
University of Alaska Fairbank
Can my GPS lead me to a sustainable future? The role of technology and lessons from three remote Arctic communities
This presentation outlines research involving 35 residents of Brevig Mission, Noatak, and Noorvik during March 2017 were asked to evaluate values and beliefs regarding technology, climate change, and subsistence. Interviewees indicated that technology was helpful in their hunting and subsistence activities, but it was also expensive and may contribute to taking larger risks. Furthermore, technology was not seen as making up entirely for the impacts arising from changing climate
Stoking the flame: Subsistence and wood energy in rural Alaska, United States
Energy costs are large and increasing in rural Alaska communities, so communities are turning to renewable energy. While, many of these communities have a mixed subsistence-cash economy, the relationship between renewable energy and subsistence has not been studied. Tanana, Alaska has a biomass program and we conducted interviews with 61 households in 2017 to understand how residents perceive the program and its association with subsistence activities. We analyzed Alaska Department of Fish & Game subsistence surveys from 89 communities to estimate differences in subsistence harvest between households that harvest wood and those that do not. Interviews indicated that people who harvest wood for the biomass program were six times more likely to engage in subsistence. Subsistence harvests were nearly double (184 kg/per capita) in households that harvested wood for personal use versus those that did not (101 kg/per capita). Equipment used for both activities was similar, and 57% respondents combined wood harvesting with other activities (e.g. subsistence, travel, etc.). Higher household incomes and employment were positively associated with subsistence participation (p < 0.001) while only household incomes was positively associated with wood harvest through the biomass program (p < 0.001). Overall, the program was perceived as having a positive effect (69%) for the community because it has created jobs (36%), saved people money (23%), promoted sharing (16%), and reduced fuel use by the community (15%). Our research shows that biomass programs have the potential to complement subsistence activities and enhance the sustainability of communities in rural Alaska that are faced with high energy costs
Technical Report for EPSCoR Fire and Ice: Coastal Margins
Current and anticipated effects from climate change in coastal regions of the Gulf of Alaska
include melting glaciers, warming ocean and riverine temperatures, and a greater proportion of
annual precipitation falling as rain. These changes in the physical environment may affect
abundance, distribution, health, and size of salmon, which will directly and indirectly impact
salmon fishing livelihoods. Fishers’ adaptations documented in prior research included increases
or decreases in fishing effort, diversification of fishing portfolios, changes in species, gear, and
harvest location, and exit from the fishery. We conducted semi-structured interviews with fishery
participants and institutional representatives involved with commercial salmon fisheries in the
Kachemak Bay and Lynn Canal regions in the Gulf of Alaska to learn about observations and
adaptations related to environmental changes, management changes, and co-occurring pressures.
Interviews were transcribed and inductively coded for themes using Atlas.ti software using
grounded theory methodology. Results will address a research gap about the local knowledge and
adaptive strategies of commercial salmon fishermen to multiple stressors in both south central
and southeast Alaska, as well as the role of local and regional institutions in supporting the
resilience of those fisheries.NSF EPSCoR Fire and Ice #OIA-1757348Ye
Whole-soil warming decreases abundance and modifies the community structure of microorganisms in the subsoil but not in surface soil
The microbial community composition in subsoils remains understudied, and it is largely unknown whether subsoil microorganisms show a similar response to global warming as microorganisms at the soil surface do. Since microorganisms are the key drivers of soil organic carbon decomposition, this knowledge gap causes uncertainty in the predictions of future carbon cycling in the subsoil carbon pool (> 50 % of the soil organic carbon stocks are below 30 cm soil depth). In the Blodgett Forest field warming experiment (California, USA) we investigated how +4 ∘C warming in the whole-soil profile to 100 cm soil depth for 4.5 years has affected the abundance and community structure of microorganisms. We used proxies for bulk microbial biomass carbon (MBC) and functional microbial groups based on lipid biomarkers, such as phospholipid fatty acids (PLFAs) and branched glycerol dialkyl glycerol tetraethers (brGDGTs). With depth, the microbial biomass decreased and the community composition changed. Our results show that the concentration of PLFAs decreased with warming in the subsoil (below 30 cm) by 28 % but was not affected in the topsoil. Phospholipid fatty acid concentrations changed in concert with soil organic carbon. The microbial community response to warming was depth dependent. The relative abundance of Actinobacteria increased in warmed subsoil, and Gram+ bacteria in subsoils adapted their cell membrane structure to warming-induced stress, as indicated by the ratio of anteiso to iso branched PLFAs. Our results show for the first time that subsoil microorganisms can be more affected by warming compared to topsoil microorganisms. These microbial responses could be explained by the observed decrease in subsoil organic carbon concentrations in the warmed plots. A decrease in microbial abundance in warmed subsoils might reduce the magnitude of the respiration response over time. The shift in the subsoil microbial community towards more Actinobacteria might disproportionately enhance the degradation of previously stable subsoil carbon, as this group is able to metabolize complex carbon sources
A Uniform Analysis of the Ly-alpha forest at z = 0 - 5: II. Measuring the mean intensity of the extragalactic ionizing background using the proximity effect
A homogeneous sample of 99 moderate resolution QSO spectra at z > 1.7 were
presented in Paper I, including 39 previously unpublished spectra from the
Multiple Mirror Telescope. The statistics of the Lyman alpha forest were
discussed. In this analysis, we demonstrate that a proximity effect is present
in the data, ie. there exists a significant (5.5) deficit of lines at
. Within 1.5 Mpc of the QSO emission redshift,
the significance does depend on QSO luminosity, in accordance with the theory
that this effect is caused by enhanced ionization of hydrogen in the vicinity
of the QSO from UV photons from the QSO itself. The photoionization model of
Bajtlik, Duncan, and Ostriker (1988) permits an estimate of the mean intensity
of the extragalactic background radiation at the Lyman limit. We compare the
results of this standard analysis with those obtained using a maximum
likelihood technique. The best fit value for is
7.0 x 10 ergs/s/cm/Hz/sr, over the redshift range
1.7 < z < 3.8, using QSO redshifts based on narrow emission lines. The best fit
value for the HI ionization rate is 1.9 x 10 s,
in good agreement with models of the background which incorporate QSOs only.
This large absorption line sample and these techniques for measuring the
background and understanding the systematics involved allow us to place what we
believe are are the firmest limits on the background at these redshifts.Comment: revised figures 13 and 14, and other minor corrections, 42 Latex
pages, 23 encapsulated Postscript figures, uses emulateapj.sty, To appear in
the Sept. 2000 ApJ
Amniotic fluid-derived stem cells for cardiovascular tissue engineering applications
Recent research has demonstrated that a population of stem cells can be isolated from amniotic fluid removed by amniocentesis that are broadly multipotent and non-tumorogenic. These amniotic fluid-derived stem cells (AFSC) could potentially provide an autologous cell source for treatment of congenital defects identified during gestation, particularly cardiovascular defects. In this review, the various methods of isolating, sorting and culturing AFSC are compared, along with techniques for inducing differentiation into cardiac myocytes and endothelial cells. Though research has not demonstrated complete and high yield cardiac differentiation, AFSC have been shown to effectively differentiate into endothelial cells and can effectively support cardiac tissue. Additionally, several tissue engineering and regenerative therapeutic approaches for the use of these cells in heart patches, injection after myocardial infarction, heart valves, vascularized scaffolds and blood vessels are summarized. These applications show great promise in the treatment of congenital cardiovascular defects, and further studies of isolation, culture, and differentiation of AFSC will help to develop their use for tissue engineering, regenerative medicine, and cardiovascular therapies
Enhancer Sequence Variants and Transcription-Factor Deregulation Synergize to Construct Pathogenic Regulatory Circuits in B-Cell Lymphoma
SummaryMost B-cell lymphomas arise in the germinal center (GC), where humoral immune responses evolve from potentially oncogenic cycles of mutation, proliferation, and clonal selection. Although lymphoma gene expression diverges significantly from GC B cells, underlying mechanisms that alter the activities of corresponding regulatory elements (REs) remain elusive. Here we define the complete pathogenic circuitry of human follicular lymphoma (FL), which activates or decommissions REs from normal GC B cells and commandeers enhancers from other lineages. Moreover, independent sets of transcription factors, whose expression was deregulated in FL, targeted commandeered versus decommissioned REs. Our approach revealed two distinct subtypes of low-grade FL, whose pathogenic circuitries resembled GC B or activated B cells. FL-altered enhancers also were enriched for sequence variants, including somatic mutations, which disrupt transcription-factor binding and expression of circuit-linked genes. Thus, the pathogenic regulatory circuitry of FL reveals distinct genetic and epigenetic etiologies for GC B-cell transformation
Loss of synergistic transcriptional feedback loops drives diverse B-cell cancers
BACKGROUND: The most common B-cell cancers, chronic lymphocytic leukemia/lymphoma (CLL), follicular and diffuse large B-cell (FL, DLBCL) lymphomas, have distinct clinical courses, yet overlapping cell-of-origin . Dynamic changes to the epigenome are essential regulators of B-cell differentiation. Therefore, we reasoned that these distinct cancers may be driven by shared mechanisms of disruption in transcriptional circuitry.
METHODS: We compared purified malignant B-cells from 52 patients with normal B-cell subsets (germinal center centrocytes and centroblasts, naïve and memory B-cells) from 36 donor tonsils using \u3e325 high-resolution molecular profiling assays for histone modifications, open chromatin (ChIP-, FAIRE-seq), transcriptome (RNA-seq), transcription factor (TF) binding, and genome copy number (microarrays).
FINDINGS: From the resulting data, we identified gains in active chromatin in enhancers/super-enhancers that likely promote unchecked B-cell receptor signaling, including one we validated near the immunoglobulin superfamily receptors FCMR and PIGR. More striking and pervasive was the profound loss of key B-cell identity TFs, tumor suppressors and their super-enhancers, including EBF1, OCT2(POU2F2), and RUNX3. Using a novel approach to identify transcriptional feedback, we showed that these core transcriptional circuitries are self-regulating. Their selective gain and loss form a complex, iterative, and interactive process that likely curbs B-cell maturation and spurs proliferation.
INTERPRETATION: Our study is the first to map the transcriptional circuitry of the most common blood cancers. We demonstrate that a critical subset of B-cell TFs and their cognate enhancers form self-regulatory transcriptional feedback loops whose disruption is a shared mechanism underlying these diverse subtypes of B-cell lymphoma.
FUNDING: National Institute of Health, Siteman Cancer Center, Barnes-Jewish Hospital Foundation, Doris Duke Foundation
A Randomized Multicentre Phase II Trial Comparing Adjuvant Therapy in Patients with Interferon Alpha-2b and 5-FU Alone or in Combination with Either External Radiation Treatment and Cisplatin (CapRI) or Radiation alone regarding Event-Free Survival – CapRI-2
<p>Abstract</p> <p>Background</p> <p>The 5-year survival of patients with resected pancreatic adenocarcinoma is still unsatisfying. The ESPAC-1 and the CONKO 001 trial proofed that adjuvant chemotherapy improves 5-year survival significantly from approximately 14% to 21%. In parallel, investigators from the Virginia Mason Clinic reported a 5-year survival rate of 55% in a phase II trial evaluating a combination of adjuvant chemotherapy, immunotherapy and external beam radiation (CapRI-scheme). Two other groups confirmed in phase II trials these results to a certain extent. However, these groups reported severe gastrointestinal toxicity (up to 93% grade 3 or 4 toxicity). In a randomized controlled phase III trial, called CapRI, 110 patients were enrolled from 2004 to 2007 in Germany and Italy to check for reproducibility. Interestingly, much less gastrointestinal toxicity was observed. However, dose-reduction due to haematological side effects had to be performed in nearly all patients. First clinical results are expected for the end of 2009.</p> <p>Methods/Design</p> <p>CapRI-2 is an open, controlled, prospective, randomized, multicentre phase II trial with three parallel arms. A de-escalation of the CapRI-scheme will be tested in two different modifications. Patients in study arm A will be treated as outpatients with the complete CapRI-scheme consisting of cisplatin, Interferon alpha-2b and external beam radiation and three cycles of 5-fluorouracil continuous infusion. In study arm B the first de-escalation will be realised by omitting cisplatin. Next, patients in study arm C will additionally not receive external beam radiation. A total of 135 patients with pathologically confirmed R0 or R1 resected pancreatic adenocarcinoma are planned to be enrolled. Primary endpoint is the comparison of the treatment groups with respect to six-month event-free-survival. An event is defined as grade 3 or grade 4 toxicity, objective tumour recurrence, or death.</p> <p>Discussion</p> <p>The aim of this clinical trial is to evaluate de-escalation of the CapRI-scheme. It is hypothesised that removal of cisplatin and radiotherapy will have no significant effect or only a minor impact on the clinical response but result in substantially lower toxicity.</p> <p>Trial Registration</p> <p>Current Controlled Trials ISRCTN79802092</p
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