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- Adapting to Symptoms of Global Warming Rather Than Addressing the CauseCairns, John Jr. (Virginia Tech, 2006)In recent years, global warming has been ignored and scientists producing evidence supporting this hypothesis have been denigrated and even investigated. However, as irrefutable evidence showing that global warming was a reality mounted, the message shifted to global warming may be occurring, but it is not caused by human activity. Now the message is shifting again, and humankind I been told to adapt to global warming instead of making an effort to reverse it.
- Aging phenomena in the two-dimensional complex Ginzburg-Landau equationLiu, Weigang; Täuber, Uwe C. (2019-11)The complex Ginzburg-Landau equation with additive noise is a stochastic partial differential equation that describes a remarkably wide range of physical systems which include coupled non-linear oscillators subject to external noise near a Hopf bifurcation instability and spontaneous structure formation in non-equilibrium systems, e.g., in cyclically competing populations or oscillatory chemical reactions. We employ a finite-difference method to numerically solve the noisy complex Ginzburg-Landau equation on a two-dimensional domain with the goal to investigate its non-equilibrium dynamics when the system is quenched into the "defocusing spiral quadrant". We observe slow coarsening dynamics as oppositely charged topological defects annihilate each other, and characterize the ensuing aging scaling behavior. We conclude that the physical aging features in this system are governed by non-universal aging scaling exponents. We also investigate systems with control parameters residing in the "focusing quadrant", and identify slow aging kinetics in that regime as well. We provide heuristic criteria for the existence of slow coarsening dynamics and physical aging behavior in the complex Ginzburg-Landau equation.
- Approximate Deconvolution Reduced Order ModelingXie, X.; Wells, D.; Wang, Z.; Iliescu, Traian (2016-10-12)This paper proposes a large eddy simulation reduced order model(LES-ROM) framework for the numerical simulation of realistic flows. In this LES-ROM framework, the proper orthogonal decomposition(POD) is used to define the ROM basis and a POD differential filter is used to define the large ROM structures. An approximate deconvolution(AD) approach is used to solve the ROM closure problem and develop a new AD-ROM. This AD-ROM is tested in the numerical simulation of the one-dimensional Burgers equation with a small diffusion coefficient(10^{-3})
- Are Humans too Numerous to Become Extinct?Cairns, John Jr. (Virginia Tech, 2009)Some claim that humans are too numerous to become extinct. However, passenger pigeon, once the most numerous birds on the planet, are now extinct. For years, humankind has been damaging its habitat, discharging toxic chemicals into the environment, and having harmful effects on agricultural productivity due to climate change. Humankind s extinction depends on the continuation of various human activities including economic growth, addiction to fossil fuel, over consumption, overpopulation, ocean acidification, and use of toxicants. If humankind wants to remain on this planet, it must start preparing for a vastly different environment on Earth.
- Are We Asking the Right Questions to Guide Our Descent From the 2007 Oil Peak?Cairns, John Jr. (Virginia Tech, 2007)Peak oil may have been reached in 2007, if so; a new source of energy will be needed. Coal would be a poor substitute as it produces twice as many greenhouse gas emissions when burnt, and biofuels have huge drawbacks, as expected when food is converted to fuel. Ethics and morals should have a major impact on the policies aiding the transition from peak oil to the eventual much reduced per capita energy consumption. Decision makers must have does humankind have a _right to endanger posterity by continuing profligate use of fossil energy?
- Averages of completely multiplicative functions over the Gaussian integersDonoso, Sebastian; Le, Anh; Moreira, Joel; Sun, Wenbo (2024)
- Beyond EcocentrismCairns, John Jr. (EcoRes Forum, 2007)In order to avoid further damage to the ecosystems, we must promote ecological health as the primary goal, which will require at least two steps beyond ecocentrism. First, one must regard the relationship between humankind and natural systems as co-evolutionary. Second, one must develop an ecolate perspective free from _feel good social, ethical, and political rhetoric.
- A biologically accurate model of directional hearing in the parasitoid fly Ormia ochraceaMikel-Stites, Max R.; Salcedo, Mary K.; Socha, John J.; Marek, Paul E.; Staples, Anne E. (Cold Spring Harbor Laboratory, 2021-09-17)Although most binaural organisms localize sound sources using neurological structures to amplify the sounds they hear, some animals use mechanically coupled hearing organs instead. One of these animals, the parasitoid fly Ormia ochracea, has astoundingly accurate sound localization abilities and can locate objects in the azimuthal plane with a precision of 2°, equal to that of humans. This is accomplished despite an intertympanal distance of only 0.5 mm, which is less than 1/100th of the wavelength of the sound emitted by the crickets that it parasitizes. In 1995, Miles et al. developed a model of hearing mechanics in O. ochracea, which works well for incoming sound angles of less than ±30°, but suffers from reduced accuracy (up to 60% error) at higher angles. Even with this limitation, it has served as the basis for multiple bio-inspired microphone designs for decades. Here, we present critical improvements to the classic O. ochracea hearing model based on information from 3D reconstructions of O. ochracea’s tympana. The 3D images reveal that the tympanal organ has curved lateral faces in addition to the flat front-facing prosternal membranes represented in the Miles model. To mimic these faces, we incorporated spatially-varying spring and damper coefficients that respond asymmetrically to incident sound waves, making a new quasi-two-dimensional (q2D) model. The q2D model has high accuracy (average errors of less than 10%) for the entire range of incoming sound angles. This improved biomechanical hearing model can inform the development of new technologies and may help to play a key role in developing improved hearing aids. Significance Statement: The ability to identify the location of sound sources is critical to organismal survival and for technologies that minimize unwanted background noise, such as directional microphones for hearing aids. Because of its exceptional auditory system, the parasitoid fly Ormia ochracea has served as an important model for binaural hearing and a source of bioinspiration for building tiny directional microphones with outsized sound localization abilities. Here, we performed 3D imaging of the fly’s tympanal organs and used the morphological information to improve the current model for hearing in O. ochracea. This model greatly expands the range of biological accuracy from ±30° to all incoming sound angles, providing a new avenue for studies of binaural hearing and further inspiration for fly-inspired technologies.
- Biophysics at the coffee shop: lessons learned working with George OsterIgoshin, Oleg A.; Chen, Jing; Xing, Jianhua; Liu, Jian; Elston, Timothy C.; Grabe, Michael; Kim, Kenneth S.; Nirody, Jasmine A.; Rangamani, Padmini; Sun, Sean X.; Wang, Hongyun; Wolgemuth, Charles (American Society for Cell Biology, 2019-07-22)Over the past 50 years, the use of mathematical models, derived from physical reasoning, to describe molecular and cellular systems has evolved from an art of the few to a cornerstone of biological inquiry. George Oster stood out as a pioneer of this paradigm shift from descriptive to quantitative biology not only through his numerous research accomplishments, but also through the many students and postdocs he mentored over his long career. Those of us fortunate enough to have worked with George agree that his sharp intellect, physical intuition, and passion for scientific inquiry not only inspired us as scientists but also greatly influenced the way we conduct research. We would like to share a few important lessons we learned from George in honor of his memory and with the hope that they may inspire future generations of scientists.
- The Biosphere Life Support System: A Unifying Concept for Ecotoxicologists and EcologistsCairns, John Jr. (Society of Environmental Toxicology and Chemistry, 2009)The biospheric life support system, consisting of natural capital and the ecosystem services it provides, has maintained favorable condition for humankind. Therefore, maintaining the health and integrity of the biospheric life support system is essential for the well being of humankind. Toxicologists know that increasing the biosphere s exposure to chemical substances will elicit a deleterious response in the biospheric life support system that human kind cannot afford. Ecologists know that the loss of biodiversity can be catastrophic to the ecosystem services that sustain human kind. Both scientific must come together and collaborate in order to communicate to the public how essential the biospehric life support system is to the survival of humankind.
- Blood, Toil, Tears, and SweatCairns, John Jr. (Asian Journal of Experimental Sciences, 2009)Some people alive in 1940 may remember a portion of the famous speech given on 13 May 1940 by Sir Winston Churchill to the British public. The speech was given during the dark days of World War II for the British when all appeared to be on the verge of being lost. Still, with a firm resolve and a realistic picture of the task before them, the British people responded to Churchill s plea with resolution and prevailed. Similarly, the climate crisis of the 21st century is global; time for remedial action is short; personal sacrifices may be appalling; and success is not assured. However, the alternative to taking action is equally horrendous _ letting billions of people starve and die and virtually eliminate the prospects of a quality life for posterity. The key lines of Churchill s speech are: _I say to the House as I said to ministers who have joined this government, I have nothing to offer but blood, toil, tears, and sweat. We have before us an ordeal of the most grievous kind. We have before us many, many months of struggle and suffering (full speech at http://famousquotes.me.uk/speeches/Winston_Churchill/2.htm). Churchill asked the people to war with all their might and with all their strength _ in short, total commitment.
- Blowing Sunshine #2: Transforming Inconvenient Truths to Convenient TruthsCairns, John Jr. (Virginia Tech, 2006)Cairns has compiled a list of opportunities for Congress and other governmental entities to _blow sunshine at the efforts of scientists justifying global warming.
- Blowing Sunshine #3: Transforming Inconvenient Truths to Convenient TruthsCairns, John Jr. (Virginia Tech, 2006)The inconvenient truth of the matter is that an overwhelming majority of mainstream scientists accept the scientific evidence on global warming. Attempting to _blow sunshine on global warming is becoming increasingly difficult because the vast majority of scientist ignore attempts to damage their reputations and integrity and keep producing more evidence via the scientific process and publishing their work in peer-reviewed, professional journals.
- Blowing Sunshine: Transforming Inconvenient Truths to Convenient TruthsCairns, John Jr. (Virginia Tech, 2006)Cairns, to please friends who frequently comment about the depressing subjects of his writing, attempted to create a list _blowing sunshine or highlighting the good news, if any, about global warming.
- Boulder dislodgement during coastal storms and tsunamis: Insights from a new ensemble modelWeiss, Robert; Irish, Jennifer L.; Goodman Tchernov, Beverly (American Geophysical Union, 2022-03-01)Boulders are excellent candidate deposits to study coastal inundation events by storms and tsunamis due to their significant preservation potential. However, it is difficult to infer how and what forcing dislodged the boulder. We present a new model that enables ensemble and Monte-Carlo-type simulations to study the sensitivity of boulder, the fluid flow, and environmental parameters. Our examples show that boulder transport is complex and nonlinear, and to acknowledge the uncertainties of the boulder's preexisting transport conditions, a range of velocities and environmental parameters should be used to quantify the flow that caused boulder dislodgement.
- Can Humans Respond to a Long-term Shortage of Renewable ResourcesCairns, John Jr. (Virginia Tech, 2011)If humanity wishes to continue to do business as usual, it must learn to adapt to the consequences of climate change and the decreased availability of renewable resources. Responding to rapid climate change will take the cooperation of the credentialed scientists who gather the evidence and the general public. It is in the best interest of human economy to preserve natural capital, which is essential to keeping the human economy afloat. The collapse of the biosphere threatens all component species, including humankind; consequently, nurturing the biosphere is a matter of self-interest.
- Can kindness and compassion survive a violent cutback in human population size?Cairns, John Jr. (Virginia Tech, 2005)The severity of the latest natural disasters and the increased probability of other major disruptions due to climate change mandate further examination of the consequences of such events on human society. Current unsustainable practices are making these types of devastating events more plausible. If not quickly addressed, these failures will destabilize both human society and the biospheric life support system.
- Can the Cheap, Convenient, Readily Available Energy Party ContinueCairns, John Jr. (Virginia Tech, 2006)Persuasive evidence indicates that oil supplies are peaking and therefore humans should expect for alternative fuels to play a major part in the future energy market.
- Cast Changes on the Ecological Stage of Earth's Evolutionary TheaterCairns, John Jr. (Virginia Tech, 2009)Change has been the Earth s most notable feature for the past 4 billion years. Earth has already passed two ecological tipping points with the acidification of the oceans and the melting glaciers and ice sheets, both caused by anthropogenic carbon dioxide emissions resulting from the combustion of fossil fuels. Unwise energy use has produced unprecedented economic and exponential population growth, both of which have had harmful consequences for the human species as well as other life forms occupying the planet. Humankind has a moral and ethical responsibility to protect the biosphere.
- Causal modeling refutes Hockett’s hypothesis that bite configuration affects human sound evolutionTarasov, Sergei; Uyeda, Josef C. (Virginia Tech, 2020-02-21)Blasi et al. (Research article, 15 March 2019) argue in support of Hockett’s hypothesis – that languages of hunter-gatherers are less likely to develop labiodental sounds than those of agricultural societies due to the former’s heavywear diet that favors edge-to-edge bite, thereby decreasing likelihood of labiodental articulation. We reanalyze the data in Blasi et al. and find little to no support in favor of the Hockett’s hypothesis. The negative association between labiodentals and hunter-gatherers instead appears to be an artifact of labiodental decline with increasing distance from Africa, which is a general trend of language phonemes.