IV. Fossil Fishes From The Miocene Ellensburg Formation, South Central Washington

The Ellensburg Formation was named for sediments deposited in the Kittitas Valley along the Yakima River near Ellensburg, Washington (Russell, 1893, 1900). Similar beds are present to the south along the leeward front of the emerging central Cascade Mountains; including the Nile, Selah, Yakima, and Toppenish basins. Further south along the Columbia River, portions of the Dalles Group, Rhododendron Formation, and Sandy River Mudstone are likely temporal equivalents; the latter two of which are found on the windward side of the uplifting Cascade Range (Farooqui, et al., 1981; Evarts et al., 2009).Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146545/1/MP 204vol4.pdfDescription of MP 204vol4.pdf : Main Articl

Fossil And Recent Mountain Suckers, Pantosteus, And Significance Of Introgression In Catostomin Fishes Of Western United States

Catostomus is the most diverse genus of fishes in western North America. Over thirty species of Catostomus and other catostomins have been classified in five recent genera, Catostomus, Deltistes, Chasmistes, Xyrauchen, and Pantosteus. Introgressed evolutionary history is apparent in all five western catostomin genera. Mountain suckers, subgenus Pantosteus, are small and medium-sized fishes that live in moderate-gradient streams in the foothills and mountains, from the Black Hills to Pacific coastal drainages and from western Canada to central Mexico. Pantosteus is distinct in its molecular as well as morphological traits, but it is polyphyletic because Catostomus (Pantosteus) columbianus shares unique, derived morphological traits with Pantosteus and mtDNA with Catostomus (s.s.), thereby identifying two genera in its ancestry. We recognize three subgroups of Pantosteus: C. (P.) discobolus group of six species is distributed in the Snake River, eastern and southern Basin and Range Province to central Mexico, the Colorado Plateau, and the Los Angeles Basin. The C. (P.) platyrhynchus species group consists of four species, found in the Columbia, Snake, Upper Missouri, Upper Green, Lahontan, and Bonneville basins. Catostomus (P.) columbianus is a separate subgroup. The Pantosteus fossil record is sparse. We describe three Miocene records of the C. (P.) discobolus group from Oregon and Washington, three Pliocene species from Idaho and Nevada, and two Pleistocene records--from the Rio Grande rift in Colorado and from the Missouri River drainage of Kansas. The Kansas record suggests a much wider range for the species during glacial periods. Miocene relatives of C. (P.) discobolus from three sites in Oregon and Washington, 11.5-8.5 million years old, are morphologically advanced suckers. The Pliocene species from southern Nevada is intermediate between its modern relatives in the surrounding Great Basin and Colorado Plateau. At least one of the two Pliocene mountain suckers in the Snake River drainage was probably involved in the hybrid ancestry of C. (P.) columbianus. The general Pantosteus pattern suggests an origin in the northwest Great Basin and Columbia Plateau, with a history of dispersal, isolation, and evolution southward through Basin and Range drainages to the Colorado Plateau and Mexico, and eastward across the Rocky Mountains to the Missouri drainage. Mountain suckers are adapted to moderate-gradient mountain streams and to scraping food from rocky substrate.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/122717/1/OP 743.pd

The Structure of the {\beta} Leonis Debris Disk

We combine nulling interferometry at 10 {\mu}m using the MMT and Keck Telescopes with spectroscopy, imaging, and photometry from 3 to 100 {\mu}m using Spitzer to study the debris disk around {\beta} Leo over a broad range of spatial scales, corresponding to radii of 0.1 to ~100 AU. We have also measured the close binary star o Leo with both Keck and MMT interferometers to verify our procedures with these instruments. The {\beta} Leo debris system has a complex structure: 1.) relatively little material within 1 AU; 2.) an inner component with a color temperature of ~600 K, fitted by a dusty ring from about 2 to 3 AU; and 3.) a second component with a color temperature of ~120 K fitted by a broad dusty emission zone extending from about ~5 AU to ~55 AU. Unlike many other A-type stars with debris disks, {\beta} Leo lacks a dominant outer belt near 100 AU.Comment: 14 page body, 3 page appendix, 15 figure

General Messenger Gauge Mediation

We discuss theories of gauge mediation in which the hidden sector consists of two subsectors which are weakly coupled to each other. One sector is made up of messengers and the other breaks supersymmetry. Each sector by itself may be strongly coupled. We provide a unifying framework for such theories and discuss their predictions in different settings. We show how this framework incorporates all known models of messengers. In the case of weakly-coupled messengers interacting with spurions through the superpotential, we prove that the sfermion mass-squared is positive, and furthermore, that there is a lower bound on the ratio of the sfermion mass to the gaugino mass.Comment: 37 pages; minor change

Radical, Reformist, and Garden-Variety Neoliberal: Coming to Terms with Urban Agriculture’s Contradictions

For many activists and scholars, urban agriculture in the Global North has become synonymous with sustainable food systems, standing in opposition to the dominant industrial agri-food system. At the same time, critical social scientists increasingly argue that urban agriculture programmes, by filling the void left by the rolling back of the social safety net, underwrite neoliberalisation. I argue that such contradictions are central to urban agriculture. Drawing on existing literature and fieldwork in Oakland, CA, I explain how urban agriculture arises from a protective counter-movement, while at the same time entrenching the neoliberal organisation of contemporary urban political economies through its entanglement with multiple processes of neoliberalisation. By focusing on one function or the other, however, rather than understanding such contradictions as internal and inherent, we risk undermining urban agriculture\u27s transformative potential. Coming to terms with its internal contradictions can help activists, policy-makers and practitioners better position urban agriculture within coordinated efforts for structural change, one of many means to an end rather than an end unto itself

Dificultades para codificar, relacionar y categorizar problemas verbales algebraicos: dos estudios con estudiantes de secundaria y profesores en formación

En resolución de problemas verbales por transferencia, la activación de problemas ya conocidos que sirvan de guía, depende de las analogías percibidas entre éstos y el problema a resolver. Se desarrollan dos estudios relacionados para analizar en qué características se basan los estudiantes para codificar problemas y detectar sus analogías, en tareas de categorización (sorting). Se utilizaron técnicas cuantitativas y cualitativas combinadas. Primero se analizó cómo los estudiantes de secundaria son influidos por diferentes variables características de problemas de ciencias. Una gran proporción de sujetos no fue capaz de percibir las analogías y diferencias adecuadas entre problemas. El segundo estudio trató de avanzar una explicación de estos resultados. El nivel académico y la familiaridad con las temáticas fueron factores significativos, pero los futuros profesores participantes mostraron demasiadas dificultades, alertando sobre la conveniencia de revisar algunos supuestos instruccionales habituales

Comparative Transmissibility of SARS-CoV-2 Variants Delta and Alpha in New England, USA

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta variant quickly rose to dominance in mid-2021, displacing other variants, including Alpha. Studies using data from the United Kingdom and India estimated that Delta was 40-80% more transmissible than Alpha, allowing Delta to become the globally dominant variant. However, it was unclear if the ostensible difference in relative transmissibility was due mostly to innate properties of Delta\u27s infectiousness or differences in the study populations. To investigate, we formed a partnership with SARS-CoV-2 genomic surveillance programs from all six New England US states. By comparing logistic growth rates, we found that Delta emerged 37-163% faster than Alpha in early 2021 (37% Massachusetts, 75% New Hampshire, 95% Maine, 98% Rhode Island, 151% Connecticut, and 163% Vermont). We next computed variant-specific effective reproductive numbers and estimated that Delta was 58-120% more transmissible than Alpha across New England (58% New Hampshire, 68% Massachusetts, 76% Connecticut, 85% Rhode Island, 98% Maine, and 120% Vermont). Finally, using RT-PCR data, we estimated that Delta infections generate on average ∼6 times more viral RNA copies per mL than Alpha infections. Overall, our evidence indicates that Delta\u27s enhanced transmissibility could be attributed to its innate ability to increase infectiousness, but its epidemiological dynamics may vary depending on the underlying immunity and behavior of distinct populations

Comparative transmissibility of SARS-CoV-2 variants Delta and Alpha in New England, USA.

The SARS-CoV-2 Delta variant rose to dominance in mid-2021, likely propelled by an estimated 40%-80% increased transmissibility over Alpha. To investigate if this ostensible difference in transmissibility is uniform across populations, we partner with public health programs from all six states in New England in the United States. We compare logistic growth rates during each variant\u27s respective emergence period, finding that Delta emerged 1.37-2.63 times faster than Alpha (range across states). We compute variant-specific effective reproductive numbers, estimating that Delta is 63%-167% more transmissible than Alpha (range across states). Finally, we estimate that Delta infections generate on average 6.2 (95% CI 3.1-10.9) times more viral RNA copies per milliliter than Alpha infections during their respective emergence. Overall, our evidence suggests that Delta\u27s enhanced transmissibility can be attributed to its innate ability to increase infectiousness, but its epidemiological dynamics may vary depending on underlying population attributes and sequencing data availability