840 research outputs found
Bostonia. Volume 15
Founded in 1900, Bostonia magazine is Boston University's main alumni publication, which covers alumni and student life, as well as university activities, events, and programs
Larval dispersal in a changing ocean with an emphasis on upwelling regions
Dispersal of benthic species in the sea is mediated primarily through small, vulnerable larvae that must survive minutes to months as members of the plankton community while being transported by strong, dynamic currents. As climate change alters ocean conditions, the dispersal of these larvae will be affected, with pervasive ecological and evolutionary consequences. We review the impacts of oceanic changes on larval transport, physiology, and behavior. We then discuss the implications for population connectivity and recruitment and evaluate life history strategies that will affect susceptibility to the effects of climate change on their dispersal patterns, with implications for understanding selective regimes in a future ocean. We find that physical oceanographic changes will impact dispersal by transporting larvae in different directions or inhibiting their movements while changing environmental factors, such as temperature, pH, salinity, oxygen, ultraviolet radiation, and turbidity, will affect the survival of larvae and alter their behavior. Reduced dispersal distance may make local adaptation more likely in well-connected populations with high genetic variation while reduced dispersal success will lower recruitment with implications for fishery stocks. Increased dispersal may spur adaptation by increasing genetic diversity among previously disconnected populations as well as increasing the likelihood of range expansions. We hypothesize that species with planktotrophic (feeding), calcifying, or weakly swimming larvae with specialized adult habitats will be most affected by climate change. We also propose that the adaptive value of retentive larval behaviors may decrease where transport trajectories follow changing climate envelopes and increase where transport trajectories drive larvae toward increasingly unsuitable conditions. Our holistic framework, combined with knowledge of regional ocean conditions and larval traits, can be used to produce powerful predictions of expected impacts on larval dispersal as well as the consequences for connectivity, range expansion, or recruitment. Based on our findings, we recommend that future studies take a holistic view of dispersal incorporating biological and oceanographic impacts of climate change rather than solely focusing on oceanography or physiology. Genetic and paleontological techniques can be used to examine evolutionary impacts of altered dispersal in a future ocean, while museum collections and expedition records can inform modern-day range shifts
Revisiting the design intent concept in the context of mechanical CAD education
[EN] Design intent is generally understood simply as a CAD model¿s anticipated behavior when altered.
However, this representation provides a simplified view of the model¿s construction and purpose,
which may hinder its general understanding and future reusability. Our vision is that design intent
communication may be improved by recognizing the multifaceted nature of design intent, and by
instructing users to convey each facet of design intent through the better-fitted CAD resource. This
paper reviews the current understanding of design intent and its relationship to design rationale and
builds on the idea that communication of design intent conveyed via CAD models can be satisfied
at three levels provided that specialized instruction is used to instruct users in selection of the most
suitable level for each intent.Otey, J.; Company, P.; Contero, M.; Camba, J. (2018). Revisiting the design intent concept in the context of mechanical CAD education. Computer-Aided Design and Applications. 15(1):47-60. https://doi.org/10.1080/16864360.2017.1353733S476015
Geology for Environmental Planning in Marion County, Indiana
Marion County is the center of a large and rapidly growing urban-industrial complex in the heartland of Indiana. The boundaries of the county and of Indianapolis, the state capital, are the same as a result of the UNIGOV concept. The rapid growth of Indianapolis and its suburbs makes effective land-use planning important for Marion County. This report is designed to provide information, based on the geologic setting of the area, that can be used for effective and environmentally sound development of the county
Acidization--IV : Experimental correlations and techniques for the acidization of sandstone cores
The experimental variables that affect the acidization of sandstone cores in a permeameter are discussed. It was found that as HCl/HF acid mixtures are injected into porous sandstone cores a reaction front between selective minerals and the acid is formed. This reaction front and a corresponding permeability front move through the core with a constant axial velocity. The time for the permeability front to move through the core is defined as the break-through time. The breakthrough time is directly proportional to the core length but inversely proportional to the HF acid concentration and the rate of injection.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/21906/1/0000313.pd
Acidization--II. The dissolution of calcite in hydrochloric acid
The dissolution of calcite in hydrochloric acid was studied with the aid of a rotating disk system at 800 psig in the temperature range -15[middle dot]6-25[deg]C. At 25[deg]C the dissolution process is mass transfer limited even at high disk rotation speeds whereas at -15[middle dot]6[deg]C both mass transfer and surface reaction rates limit the dissolution rate. The multicomponent coupled ionic diffusive fluxes of reactants and products were defined by using the gradient of the electrochemical potentials as driving forces for the diffusion. The activity coefficients used in calculating the multicomponent diffusivities of the diffusing species were estimated by Harned's rule. The concentration profiles of the ions in the boundary layer were then determined by numerically integrating the system of coupled convective diffusion equations. The effects of variable density, viscosity, and high mass fluxes on the fluid velocity in the boundary layer were taken into account. The rate of the surface reaction was found to be proportional to the 0[middle dot]63 power of the surface hydrochloric acid concentration. Analysis of the experiments suggests that the absorption of hydrogen ion (described by a Freundlich adsorption isotherm) on the solid calcite surface and subsequent reaction of the adsorbed hydrogen ion with the solid calcite matrix is the reaction mechanism.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/22018/1/0000434.pd
Comparison of Positive and Negative Verbal Cueing on Muscular Endurance in College - Aged Females
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