Mammal Fleas (Siphonaptera: Ceratophyllidae) New for Alaska and the Southeastern Mainland Collected During Seven Years of a Field Survey of Small Mammals

Ten taxa of mammal fleas were among 124 collection records from 12 host species (one shrew, nine rodents and two carnivores), at 72 localities on the southeastern Alaska mainland in 1989 and during an extensive survey of mammals in 1992-1995 and 1997-1999. Megabothris asio megacolpus (Jordan) ex Microtus pennsylvanicus (Ord), Malaraeus telchinus (Rothschild) ex Peromyscus keeni (Rhoads) and Clethrionomys gapperi (Vigors) are new fleas for Alaska. Orchopeas caedens (Jordan) ex Tamiasciurus hudsonicus (Erxleben) is a new flea for southeastern Alaska. Synaptomys borealis (Richardson) is a new host record for Opisodasys k. keeni (Baker). The other six taxa of fleas collected were Hystrichopsylla dippiei spinata Holland, H. o. occidentalis Holland, Catallagia charlottensis (Baker), Ceratophyllus ciliatus protinus Jordan, Megabothris abantis (Rothschild) and Opisodasys vesperalis (Jordan). Of these, H. o. occidentalis, C. charlottensis and M. abantis have seven new host records for the southeastern Alaska mainland. Distribution patterns of the fleas and their host relationships in North America are discussed

Deer mouse hemoglobin exhibits a lowered oxygen affinity owing to mobility of the E helix

The deer mouse, Peromyscus maniculatus, exhibits altitude-associated variation in hemoglobin oxygen affinity. To examine the structural basis of this functional variation, the structure of the hemoglobin was solved. Recombinant hemoglobin was expressed in Escherichia coli and was purified by ion-exchange chromatography. Recombinant hemoglobin was crystallized by the hangingdrop vapor-diffusion method using polyethylene glycol as a precipitant. The obtained orthorhombic crystal contained two subunits in the asymmetric unit. The refined structure was interpreted as the aquo-met form. Structural comparisons were performed among hemoglobins from deer mouse, house mouse and human. In contrast to human hemoglobin, deer mouse hemoglobin lacks the hydrogen bond between α1Trp14 in the A helix and α1Thr67 in the E helix owing to the Thr67Ala substitution. In addition, deer mouse hemoglobin has a unique hydrogen bond at the α1β1 interface between residues α1Cys34 and β1Ser128

A Pipeline Strategy for Grain Crop Domestication

In the interest of diversifying the global food system, improving human nutrition, and making agriculture more sustainable, there have been many proposals to domesticate wild plants or complete the domestication of semidomesticated orphan crops. However, very few new crops have recently been fully domesticated. Many wild plants have traits limiting their production or consumption that could be costly and slow to change. Others may have fortuitous preadaptations that make them easier to develop or feasible as high-value, albeit low-yielding, crops. To increase success in contemporary domestication of new crops, we propose a pipeline approach, with attrition expected as species advance through the pipeline. We list criteria for ranking domestication candidates to help enrich the starting pool with more preadapted, promising species. We also discuss strategies for prioritizing initial research efforts once the candidates have been selected: developing higher value products and services from the crop, increasing yield potential, and focusing on overcoming undesirable traits. Finally, we present new-crop case studies that demonstrate that wild species’ limitations and potential (in agronomic culture, shattering, seed size, harvest, cleaning, hybridization, etc.) are often only revealed during the early phases of domestication. When nearly insurmountable barriers were reached in some species, they have been (at least temporarily) eliminated from the pipeline. Conversely, a few species have moved quickly through the pipeline as hurdles, such as low seed weight or low seed number per head, were rapidly overcome, leading to increased confidence, farmer collaboration, and program expansion.Fil: DeHaan, Lee R.. The Land Institute; Estados UnidosFil: Van Tassel, David L.. The Land Institute; Estados UnidosFil: Anderson, James A.. University of Minnesota; Estados UnidosFil: Asselin, Sean R.. University of Manitoba; CanadáFil: Barnes, Richard. University of Minnesota; Estados UnidosFil: Baute, Gregory J.. University of British Columbia; CanadáFil: Cattani, Douglas J.. University of Manitoba; CanadáFil: Culman, Steve W.. Ohio State University; Estados UnidosFil: Dorn, Kevin M.. University of Minnesota; Estados UnidosFil: Hulke, Brent S.. United States Department of Agriculture. Agriculture Research Service; Estados UnidosFil: Kantar, Michael. University of British Columbia; CanadáFil: Larson, Steve. Forage and Range Research Laboratory; Estados UnidosFil: David Marks, M.. University of Minnesota; Estados UnidosFil: Miller, Allison J.. Saint Louis University; Estados UnidosFil: Poland, Jesse. Kansas State University; Estados UnidosFil: Ravetta, Damián Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Museo Paleontológico Egidio Feruglio; ArgentinaFil: Rude, Emily. University of Wisconsin; Estados UnidosFil: Ryan, Matthew R.. Cornell University; Estados UnidosFil: Wyse, Don. University of Minnesota; Estados UnidosFil: Zhang, Xiaofei. University of Minnesota; Estados Unido

Intraguild predation of water scorpion Laccotrephes japonensis (Nepidae: Heteroptera)

Previous work on community structure of the invertebrate fauna of Japanese wetlands indicates the presence of intraguild predation between the heteropterans Laccotrephes japonensis (Nepidae) and Kirkaldyia deyrolli (Belostomatidae). We designed a series of experiments to understand the biotic interactions of several species of sympatric heteroptera and their shared prey. Adult Laccotrephes japonensis (Nepidae), first-instar nymph of Kirkaldyia (=Lethocerus) deyrolli (Belostomatidae), Hyla japonica tadpole, and fourth-instar nymph of Appasus japonicus (Belostomatidae) have been shown to be intraguild predator, intraguild prey, common prey, and prey of L. japonensis, respectively. To further understand the factors affecting prey preference by L. japonensis, we also examined the comparison of swimming speed in the three prey animals (K. deyrolli first-instar nymph, A. japonicus fourth-instar nymph, and H. japonica tadpole), and effects of prey animals on weight gain of L. japonensis adult. Despite there being no significant difference in weight gain or swimming speed of the three prey species, L. japonensis exhibited a strong preference for the 1st-instar nymph of K. deyrolli. We suggested that this may be evidence for one of elimination of a potential competitor, K. deyrolli, by L. japonensis through intraguild predation

Glaciation Effects on the Phylogeographic Structure of Oligoryzomys longicaudatus (Rodentia: Sigmodontinae) in the Southern Andes

The long-tailed pygmy rice rat Oligoryzomys longicaudatus (Sigmodontinae), the major reservoir of Hantavirus in Chile and Patagonian Argentina, is widely distributed in the Mediterranean, Temperate and Patagonian Forests of Chile, as well as in adjacent areas in southern Argentina. We used molecular data to evaluate the effects of the last glacial event on the phylogeographic structure of this species. We examined if historical Pleistocene events had affected genetic variation and spatial distribution of this species along its distributional range. We sampled 223 individuals representing 47 localities along the species range, and sequenced the hypervariable domain I of the mtDNA control region. Aligned sequences were analyzed using haplotype network, Bayesian population structure and demographic analyses. Analysis of population structure and the haplotype network inferred three genetic clusters along the distribution of O. longicaudatus that mostly agreed with the three major ecogeographic regions in Chile: Mediterranean, Temperate Forests and Patagonian Forests. Bayesian Skyline Plots showed constant population sizes through time in all three clusters followed by an increase after and during the Last Glacial Maximum (LGM; between 26,000–13,000 years ago). Neutrality tests and the “g” parameter also suggest that populations of O. longicaudatus experienced demographic expansion across the species entire range. Past climate shifts have influenced population structure and lineage variation of O. longicaudatus. This species remained in refugia areas during Pleistocene times in southern Temperate Forests (and adjacent areas in Patagonia). From these refugia, O. longicaudatus experienced demographic expansions into Patagonian Forests and central Mediterranean Chile using glacial retreats

Reticulate evolution: frequent introgressive hybridization among chinese hares (genus lepus) revealed by analyses of multiple mitochondrial and nuclear DNA loci

<p>Abstract</p> <p>Background</p> <p>Interspecific hybridization may lead to the introgression of genes and genomes across species barriers and contribute to a reticulate evolutionary pattern and thus taxonomic uncertainties. Since several previous studies have demonstrated that introgressive hybridization has occurred among some species within <it>Lepus</it>, therefore it is possible that introgressive hybridization events also occur among Chinese <it>Lepus </it>species and contribute to the current taxonomic confusion.</p> <p>Results</p> <p>Data from four mtDNA genes, from 116 individuals, and one nuclear gene, from 119 individuals, provides the first evidence of frequent introgression events via historical and recent interspecific hybridizations among six Chinese <it>Lepus </it>species. Remarkably, the mtDNA of <it>L. mandshuricus </it>was completely replaced by mtDNA from <it>L. timidus </it>and <it>L. sinensis</it>. Analysis of the nuclear DNA sequence revealed a high proportion of heterozygous genotypes containing alleles from two divergent clades and that several haplotypes were shared among species, suggesting repeated and recent introgression. Furthermore, results from the present analyses suggest that Chinese hares belong to eight species.</p> <p>Conclusion</p> <p>This study provides a framework for understanding the patterns of speciation and the taxonomy of this clade. The existence of morphological intermediates and atypical mitochondrial gene genealogies resulting from frequent hybridization events likely contribute to the current taxonomic confusion of Chinese hares. The present study also demonstrated that nuclear gene sequence could offer a powerful complementary data set with mtDNA in tracing a complete evolutionary history of recently diverged species.</p

Conjuntos excepcionais e alguns problemas de Mahler

Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Exatas, Departamento de Matemática, 2017.Seja f uma função inteira e transcendente. Denotamos por Sf o conjunto de todos os α ∈ ´Q tais que f(α) ∈ ´Q (o conjunto excepcional de f). Nessa dissertação, mostraremos quais subconjuntos de ´Q podem ser o conjunto excepcional de alguma função inteira e transcendente. Além disso, trataremos de dois problemas de Mahler relacionados a propriedades de funções inteiras e transcendentes. Mostraremos que existem funções inteiras e transcendentes que levam um subconjunto dos números de Liouville nele mesmo e daremos uma resposta positiva ao Problema B de Mahler: Problema B: Existe uma função inteira e transcendente f(z) = Σn =0 ∞ a nz n com coeficientes racionais tal que f( ´Q ) ⊆ ´Q e f−1( ´Q ) ⊆ ´Q ? .Let f be an entire transcendental function. We denote by Sf the set of all α ∈ ´Q such that f(α) ∈ ´Q (exceptional set of f). Throughout this dissertation, we will show which subsets of ´Q can be the exceptional set of some entire transcendental function. Moreover, we will deal with two of Mahler’s problems related to properties of entire transcendental functions. We will show that there are entire transcendental functions that map a subset of Liouville numbers in itself and we will give a positive answer for Mahler’s Problem B: Problem B: Is there an entire transcendental function f(z) = Σn =0 ∞ a nz n with rational coefficients such that que f( ´Q ) ⊆ ´Q e f−1( ´Q ) ⊆ ´Q ?

Lessons Learned from Development and Implementation of a STEM Service Learning Project

What questions and conversations do 3-way multi-level blended STEM teaching partnerships generate? Participating college faculty reflect on their scholarly teaching of cooperative problem-based learning designed to empower college STEM majors to foster development of scientific habits of mind in young students. Themes include mentoring techniques, feedback mechanisms, and emerging signature pedagogies for this type of college internship experience. In the service learning partnership explored in this session, college interns teach a semester-long inquiry-based enrichment program which places 5th graders in the role of science sleuths. Science faculty teach pedagogy to their college interns while partnering with them to design pedagogy, labs, and science mysteries based on the specifications, formative, and summative feedback from elementary teachers. The college interns guide their 5th grade students to generate hypotheses, perform experiments to test these hypotheses, interpret lab results, and propose a solution to a science mystery based on their results. The faculty panel will engage in interactive reflection with the audience exploring questions and emergent themes based on summaries of stakeholder surveys and focus groups. Lessons learned from this teaching and learning experience will be presented in an interactive format designed to explore generalizability and pose new questions in the ongoing research