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Appleton, WI, United States

Lawrence University is a liberal arts college and conservatory of music in Appleton, Wisconsin. Founded in 1847, the school held its first classes on November 12, 1849. Lawrence was the second college in the United States to be founded as a coeducational institution. The school is a member of the Colleges That Change Lives and one of the Great Books Colleges.In a study by the National Science Foundation, Lawrence ranked 28th nationally in the percentage of graduates who go on to earn doctorates. Wikipedia.

Pseudotachylytes and two distinct types of cataclasite in the Otago Schist at Tucker Hill, South Island, New Zealand, provide evidence for both seismic slip and aseismic creep on a normal fault zone during regional crustal extension in late Cretaceous time. Regional geologic evidence suggests that the fault had its present low-angle dip (ca. 10°) at the time it was active. 'Type A' cataclasites, presumably aseismic, can be recognized by bi-fractal grain size distributions, monomict composition, angular clasts of uniform textural maturity, and a crude fabric defined by oriented grains and transgranular fractures. 'Type B' cataclasites, possibly cosesimic, have characteristics consistent with fluidized grain flow, including heterogeneous clast shapes and types, a bimodal grain size distribution, intrusive relationships with other rocks, and the absence of any fabric or transecting fractures. Pseudotachylyte, which occurs as fault veins, injection veins and more complex types of intrusive structures, consistently cuts across and invades Type A cataclasites but is both intrusive into and included as clasts in Type B cataclasites.These relationships are consistent with a fault evolution model in which the development of a damage zone through aseismic cataclasis (Type A) facilitates the formation of pseudotachylyte in a subsequent seismic event by providing a permeable matrix through which fluids can drain in the early stages of slip, thereby maintaining frictional contact between rock surfaces. The formation of pseudotachylyte, in turn, may seal the fault zone and lead to thermal pressurization in a later seismic cycle, forming fluidized (Type B) cataclasites. Seismic slip on the low-angle normal fault zone at Tucker Hill may have occurred by two distinct modes of dynamic weakening - melt lubrication and thermal pressurization - in successive seismic events.Although there is a perception among geologists that pseudotachylyte is most likely to form in intact, crystalline rocks, geophysical models of fault zones clearly demonstrate that pseudotachylyte formation is actually suppressed in low-permeability rock because any fluids present would be unable to escape the fault zone and thermal pressurization would rapidly reduce frictional resistance. The paradigmatic occurrences of pseudotachylyte in otherwise pristine crystalline rocks probably represent somewhat exceptional circumstances (single rupture events at very high effective stress in dry rock). Coseismic frictional melts may actually be more common in hydrated rocks like the schist at Tucker Hill, but harder to recognize and also vulnerable to overprinting as a fault zone matures. In such rocks, pseudotachylyte may represent an intermediate stage in the evolution of a fault zone, the period between the formation of a high-permeability damage zone and the development of a low-permeability fault core. © 2010 Elsevier B.V. Source

Schreiber A.M.,Lawrence University
Current Topics in Developmental Biology | Year: 2013

The most asymmetrically shaped and behaviorally lateralized of all the vertebrates, the flatfishes are an endless source of fascination to all fortunate enough to study them. Although all vertebrates undergo left-right asymmetric internal organ placement during embryogenesis, flatfish are unusual in that they experience an additional period of postembryonic asymmetric remodeling during metamorphosis, and thus deviate from a bilaterally symmetrical body plan more than other vertebrates. As with amphibian metamorphosis, all the developmental programs of flatfish metamorphosis are ultimately under the control of thyroid hormone. At least one gene pathway involved in embryonic organ lateralization (nodal-lefty-pitx2) is re-expressed in the larval stage during flatfish metamorphosis. Aspects of modern flatfish ontogeny, such as the gradual translocation of one eye to the opposite side of the head and the appearance of key neurocranial elements during metamorphosis, seem to elegantly recapitulate flatfish phylogeny. This chapter highlights the current state of knowledge of the developmental biology of flatfish metamorphosis with emphases on the genetic, morphological, behavioral, and evolutionary origins of flatfish asymmetry. © 2013 Elsevier Inc.. Source

Heim N.A.,Stanford University | Knope M.L.,Stanford University | Knope M.L.,Lawrence University | Schaal E.K.,Stanford University | And 2 more authors.
Science | Year: 2015

Cope's rule proposes that animal lineages evolve toward larger body size over time. To test this hypothesis across all marine animals, we compiled a data set of body sizes for 17,208 genera of marine animals spanning the past 542 million years. Mean biovolume across genera has increased by a factor of 150 since the Cambrian, whereas minimum biovolume has decreased by less than a factor of 10, and maximum biovolume has increased by more than a factor of 100,000. Neutral drift from a small initial value cannot explain this pattern. Instead, most of the size increase reflects differential diversification across classes, indicating that the pattern does not reflect a simple scaling-up of widespread and persistent selection for larger size within populations. Source

Brooks T.M.,International Union for Conservation of Nature | Lamoreux J.F.,National Fish and Wildlife Foundation | Soberon J.,Lawrence University
Trends in Ecology and Evolution | Year: 2014

The characteristics of the physical science basis and mitigation of climate change lend themselves well to a science-policy interface focused on global assessment-the function of the Intergovernmental Panel on Climate Change (IPCC). By contrast, the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) needs three additional functions of knowledge generation, capacity-building, and policy support, in addition to traditional assessment, and the same is true for climate change adaptation. These functions are included in the work program for IPBES, but their total share of the budget, currently less than a third, is inadequate. For climate change adaptation they are delivered by mechanisms like the Nairobi Work Programme and the Adaptation Committee, which should similarly receive greater attention. © 2014. Source

Agency: NSF | Branch: Standard Grant | Program: | Phase: GEOBIOLOGY & LOW TEMP GEOCHEM | Award Amount: 39.61K | Year: 2016

To determine how future precipitation might change, it is important to have a baseline of how precipitation changed in the past. However, determining past precipitation, prior to the generation of instrumental records, has remained challenging and necessitates the use of precipitation proxies that are preserved in the geologic record. Biological proxies, such as leaf waxes, hold promise in this regard as the hydrogen isotopic composition of leaf wax primarily reflects that of precipitation. Therefore, leaf waxes preserved in lake sediments are a potential source of high resolution information about how precipitation and the water cycle have changed over geologic time. However, the transfer of modern leaf waxes to lake sediments appears to introduce offsets in hydrogen isotope values. This project will help define these offsets and identify the factors that control them, thus allowing for improved reconstructions of past hydrological conditions. Until these offsets are evaluated, and their influence measured, the quantitative link between sedimentary leaf wax and precipitation will remain limited. Identification of these factors will allow selection of lakes where the effects of these offsets are minimal. This is critical for constraining past changes in hydrology prior to the instrumental record and will help anticipate future hydrologic change. This project will benefit society by creating educational and research experiences for undergraduates through interdisciplinary collaborations with St. Lawrence University, a primarily undergraduate institution. This will improve STEM field retention by providing research and training experiences for undergraduate students to develop advanced research skill sets, expand scientific understanding, and strengthen preparation for graduate studies or a career in the geosciences. Finally, this research will promote a broader public understanding of the geosciences and appreciation of scientific research by expanding on museum exhibits in collaboration with the Cincinnati Museum Center, a large urban cultural institution.

Past precipitation remains a challenge to quantify. Biological proxies, such as leaf waxes, hold promise in this regard as the hydrogen isotopic composition of leaf wax primarily reflects plant source water (i.e., precipitation). However, quantitative paleohydrology, as inferred from precipitation hydrogen isotopic composition, is limited by a poor understanding of the taphonomic processes governing the source, integration, and transport of leaf waxes from plants to sediments. This project will address two significant gaps in our understanding of lake sediment leaf waxes. First, the investigators will determine how vegetation proximity influences leaf wax hydrogen isotope signals in lake sediments. Second, they will determine how important reworking of older leaf waxes via fluvial erosion impacts the apparent age of leaf waxes in lake sediments. This project examines these two processes in temperate lakes in the Adirondack Mountains, NY, USA. Research methods will include forest inventorying, modern leaf wax (n-alkane and n-alkanoic acid) molecular and isotope (hydrogen, carbon) characterization, lake sediment coring and dating (210Pb, 137Cs, 14C), and compound-specific radiocarbonanalyses of n-alkanes in lake sediments, catchment soils, and fluvial suspended sediments. The project will benefit society by 1) establishing partnerships with St. Lawrence University, a primarily undergraduate institution, to develop interdisciplinary collaborations and undergraduate research opportunities, create graduate student mentoring opportunities, and provide a hands-on isotope workshop for undergraduates; 2) improving STEM field retention by providing research and training experiences for two undergraduate students per year to develop advanced research skill sets, expand scientific understanding, and strengthen preparation for graduate studies or a career in the geosciences; 3) increasing the number of women in STEM fields by support of a Ph.D. student and an undergraduate students; 4) providing mentoring to enhance the educational and career development of undergraduate and graduate students, and improving the success of mentoring approaches through regular assessment and professional development; and 5) promoting broader public understanding of the geosciences and appreciation of scientific research by expanding on museum exhibits in collaboration with the Cincinnati Museum of Center, a large urban cultural institution.

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