14 research outputs found
Different Prey Resources Suggest Little Competition Between Non-Native Frogs and Insectivorous Birds Despite Isotopic Niche Overlap
Non-native amphibians often compete with native amphibians in their introduced range, but their competitive effects on other vertebrates are less well known. The Puerto Rican coqui frog (Eleutherodactylus coqui) has colonized the island of Hawaii, and has been hypothesized to compete with insectivorous birds and bats. To address if the coqui could compete with these vertebrates, we used stable isotope analyses to compare the trophic position and isotopic niche overlap between the coqui, three insectivorous bird species, and the Hawaiian hoary bat. Coquis shared similar trophic position to Hawaii amakihi, Japanese white-eye, and red-billed leiothrix. Coquis were about 3 ‰ less enriched in δ15N than the Hawaiian hoary bat, suggesting the bats feed at a higher trophic level than coquis. Analyses of potential diet sources between coquis and each of the three bird species indicate that there was more dietary overlap between bird species than any of the birds and the coqui. Results suggest that Acari, Amphipoda, and Blattodea made up \u3e90% of coqui diet, while Araneae made up only 2% of coqui diet, but approximately 25% of amakihi and white-eye diet. The three bird species shared similar proportions of Lepidoptera larvae, which were ~25% of their diet. Results suggest that coquis share few food resources with insectivorous birds, but occupy a similar trophic position, which could indicate weak competition. However, resource competition may not be the only way coquis impact insectivorous birds, and future research should examine whether coqui invasions are associated with changes in bird abundance
Different prey resources suggest little competition between non-native frogs and insectivorous birds despite isotopic niche overlap
Electrospun fibre diameter, not alignment, affects mesenchymal stem cell differentiation into the tendon/ligament lineage
Bioreactor System Using Noninvasive Imaging and Mechanical Stretch for Biomaterial Screening
Screening biomaterial and tissue systems in vitro, for guidance of performance in vivo, remains a major requirement in the field of tissue engineering. It is critical to understand how culture stimulation affects both tissue construct maturation and function, with the goal of eliminating resource-intensive trial-and-error screening and better matching specifications for various in vivo needs. We present a multifunctional and robust bioreactor design that addresses this need. The design enables a range of mechanical inputs, durations, and frequencies to be applied in coordination with noninvasive optical assessments. A variety of biomaterial systems, including micro- and nano-fiber and porous sponge biomaterials, as well as cell-laden tissue engineering constructs were used in validation studies in order to demonstrate the versatility and utility of this new bioreactor design. The silk-based biomaterials highlighted in these studies offered several unique optical signatures for use in label-free nondestructive imaging that allowed for sequential profiling. Both short- and long-term culture studies were conducted to evaluate several practical scenarios of usage: on a short-term basis, we demonstrate that construct cellularity can be monitored by usage of nonpermanent dyes; on a more long-term basis, we show that cell ingrowth can be monitored by GFP-labeling and construct integrity probed with concurrent load/displacement data. The ability to nondestructively track cells, biomaterials, and new matrix formation without harvesting designated samples at each time point will lead to less resource-intensive studies and should enhance our understanding and the discovery of biomaterial designs related to functional tissue engineering
Static and Cyclic Mechanical Loading of Mesenchymal Stem Cells on Elastomeric, Electrospun Polyurethane Meshes
An Integrated Next-Generation Sequencing System for Analyzing DNA Mutations, Gene Fusions, and RNA Expression in Lung Cancer
An Integrated Next-Generation Sequencing System for Analyzing DNA Mutations, Gene Fusions, and RNA Expression in Lung Cancer
We developed and characterized a next-generation sequencing (NGS) technology for streamlined analysis of DNA and RNA using low-input, low-quality cancer specimens. A single-workflow, targeted NGS panel for non–small cell lung cancer (NSCLC) was designed covering 135 RNA and 55 DNA disease-relevant targets. This multiomic panel was used to assess 219 formalin-fixed paraffin-embedded NSCLC surgical resections and core needle biopsies. Mutations and expression phenotypes were identified consistent with previous large-scale genomic studies, including mutually exclusive DNA and RNA oncogenic driver events. Evaluation of a second cohort of low cell count fine-needle aspirate smears from the BATTLE-2 trial yielded 97% agreement with an independent, validated NGS panel that was used with matched surgical specimens. Collectively, our data indicate that broad, clinically actionable insights that previously required independent assays, workflows, and analyses to assess both DNA and RNA can be conjoined in a first-tier, highly multiplexed NGS test, thereby providing faster, simpler, and more economical results
Moving beyond panaceas in fisheries governance
In fisheries management—as in environmental governance more generally—regulatory arrangements that are thought to be helpful in some contexts frequently become panaceas or, in other words, simple formulaic policy prescriptions believed to solve a given problem in a wide range of contexts, regardless of their actual consequences. When this happens, management is likely to fail, and negative side effects are common. We focus on the case of individual transferable quotas to explore the panacea mindset, a set of factors that promote the spread and persistence of panaceas. These include conceptual narratives that make easy answers like panaceas seem plausible, power disconnects that create vested interests in panaceas, and heuristics and biases that prevent people from accurately assessing panaceas. Analysts have suggested many approaches to avoiding panaceas, but most fail to conquer the underlying panacea mindset. Here, we suggest the codevelopment of an institutional diagnostics toolkit to distill the vast amount of information on fisheries governance into an easily accessible, open, on-line database of checklists, case studies, and related resources. Toolkits like this could be used in many governance settings to challenge users’ understandings of a policy’s impacts and help them develop solutions better tailored to their particular context. They would not replace the more comprehensive approaches found in the literature but would rather be an intermediate step away from the problem of panaceas
