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Search Results: 1 - 10 of 160482 matches for " George H. Burgess "
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Seasonal Distribution and Historic Trends in Abundance of White Sharks, Carcharodon carcharias, in the Western North Atlantic Ocean
Tobey H. Curtis, Camilla T. McCandless, John K. Carlson, Gregory B. Skomal, Nancy E. Kohler, Lisa J. Natanson, George H. Burgess, John J. Hoey, Harold L. Pratt
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0099240
Abstract: Despite recent advances in field research on white sharks (Carcharodon carcharias) in several regions around the world, opportunistic capture and sighting records remain the primary source of information on this species in the northwest Atlantic Ocean (NWA). Previous studies using limited datasets have suggested a precipitous decline in the abundance of white sharks from this region, but considerable uncertainty in these studies warrants additional investigation. This study builds upon previously published data combined with recent unpublished records and presents a synthesis of 649 confirmed white shark records from the NWA compiled over a 210-year period (1800-2010), resulting in the largest white shark dataset yet compiled from this region. These comprehensive records were used to update our understanding of their seasonal distribution, relative abundance trends, habitat use, and fisheries interactions. All life stages were present in continental shelf waters year-round, but median latitude of white shark occurrence varied seasonally. White sharks primarily occurred between Massachusetts and New Jersey during summer and off Florida during winter, with broad distribution along the coast during spring and fall. The majority of fishing gear interactions occurred with rod and reel, longline, and gillnet gears. Historic abundance trends from multiple sources support a significant decline in white shark abundance in the 1970s and 1980s, but there have been apparent increases in abundance since the 1990s when a variety of conservation measures were implemented. Though the white shark's inherent vulnerability to exploitation warrants continued protections, our results suggest a more optimistic outlook for the recovery of this iconic predator in the Atlantic.
Habitat Structure and Colonial Behaviorin Metepeira Spinipes (Araneae: Araneidae),an Orb Weaving Spider From Mexico
George W. Uetz,J. Wesley Burgess
Psyche , 1979, DOI: 10.1155/1979/76206
A Re-Evaluation of the Size of the White Shark (Carcharodon carcharias) Population off California, USA
George H. Burgess, Barry D. Bruce, Gregor M. Cailliet, Kenneth J. Goldman, R. Dean Grubbs, Christopher G. Lowe, M. Aaron MacNeil, Henry F. Mollet, Kevin C. Weng, John B. O'Sullivan
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0098078
Abstract: White sharks are highly migratory and segregate by sex, age and size. Unlike marine mammals, they neither surface to breathe nor frequent haul-out sites, hindering generation of abundance data required to estimate population size. A recent tag-recapture study used photographic identifications of white sharks at two aggregation sites to estimate abundance in “central California” at 219 mature and sub-adult individuals. They concluded this represented approximately one-half of the total abundance of mature and sub-adult sharks in the entire eastern North Pacific Ocean (ENP). This low estimate generated great concern within the conservation community, prompting petitions for governmental endangered species designations. We critically examine that study and find violations of model assumptions that, when considered in total, lead to population underestimates. We also use a Bayesian mixture model to demonstrate that the inclusion of transient sharks, characteristic of white shark aggregation sites, would substantially increase abundance estimates for the adults and sub-adults in the surveyed sub-population. Using a dataset obtained from the same sampling locations and widely accepted demographic methodology, our analysis indicates a minimum all-life stages population size of >2000 individuals in the California subpopulation is required to account for the number and size range of individual sharks observed at the two sampled sites. Even accounting for methodological and conceptual biases, an extrapolation of these data to estimate the white shark population size throughout the ENP is inappropriate. The true ENP white shark population size is likely several-fold greater as both our study and the original published estimate exclude non-aggregating sharks and those that independently aggregate at other important ENP sites. Accurately estimating the central California and ENP white shark population size requires methodologies that account for biases introduced by sampling a limited number of sites and that account for all life history stages across the species' range of habitats.
Statistical Description of Nonrelativistic Classical Systems  [PDF]
George H. Goedecke
Journal of Modern Physics (JMP) , 2017, DOI: 10.4236/jmp.2017.85050
Abstract: We prove that any nonrelativistic classical system must obey a statistical wave equation that is exactly the same as the Schrödinger equation for the system, including the usual “canonical quantization” and Hamiltonian operator, provided an unknown constant is set equal to . We show why the two equations must have exactly the same sets of solutions, whereby this classical statistical theory (CST) and nonrelativistic quantum mechanics may differ only in their interpretations of the same quantitative results. We identify some of the different interpretations. We show that the results also imply nonrelativistic Lagrangian classical mechanics and the associated Newtonian laws of motion. We prove that the CST applied to a nonrelativistic rigid rotator yields spin angular momentum operators that obey the quantum commutation rules and allow both integer and half-odd-integer spin. We also note that the CST applied to systems of identical massive particles is mathematically equivalent to nonrelativistic quantum field theory for those particles.
Statistical Wave Equation for Nonrelativistic Rigid Body Motions  [PDF]
George H. Goedecke
Journal of Modern Physics (JMP) , 2017, DOI: 10.4236/jmp.2017.812114
Abstract: In this work, the general nonrelativistic classical statistical theory presented in an earlier paper (J. Mod. Phys. 8, 786 (2017)) is applied in detail to the Euler angle and center-of-mass coordinates of an extended rigid body with arbitrary distributions of mass and electric charge. Results include the following: 1) The statistical theory spin angular momentum operators are independent of the body’s morphology; 2) These operators obey the usual quantum commutation rules in a non-rotating center-of-mass (CM) reference frame, but left-handed rules in a rotating body-fixed CM frame; 3) Physical boundary conditions on the Euler angle wavefunctions restrict all mixed spin wavefunctions to a superposition of half-odd-integer spin eigenstates only, or integer spin eigenstates only; 4) Spin s eigenfunctions are also Hamiltonian eigenfuctions only if at least two of the body’s principal moments of inertia are equal; 5) For a spin s body with nonzero charge density in a magnetic field, the theory automatically yields 2s+1 coupled wave equations, valid for any gyromagnetic ratio; and 6) For spin 1/2 the two coupled equations become a Pauli-Schrödinger equation, with the Pauli matrices appearing automatically in the interaction Hamiltonian.
Is the Nintendo Wii Fit really acceptable to older people?: a discrete choice experiment
Kate Laver, Julie Ratcliffe, Stacey George, Leonie Burgess, Maria Crotty
BMC Geriatrics , 2011, DOI: 10.1186/1471-2318-11-64
Abstract: A DCE was administered to 21 participants in an interview style format prior to, and following several sessions of using the Wii Fit in physiotherapy. The physiotherapist prescribed the Wii Fit activities, supervised and supported the patient during the therapy sessions. Attributes included in the DCE were: mode of therapy (traditional or using the Wii Fit), amount of therapy, cost of therapy program and percentage of recovery made. Data was analysed using conditional (fixed-effects) logistic regression.Prior to commencing the therapy program participants were most concerned about therapy time (avoiding programs that were too intensive), and the amount of recovery they would make. Following the therapy program, participants were more concerned with the mode of therapy and preferred traditional therapy programs over programs using the Wii Fit.The usefulness of the Wii Fit as a therapy tool with hospitalised older people is limited not only by the small proportion of older people who are able to use it, but by older people's preferences for traditional approaches to therapy. Mainstream media portrayals of the popularity of the Wii Fit with older people may not reflect the true acceptability in the older hospitalised population.Health and aged care services are exploring new ways of delivering therapy programs in the context of an aging population, increased demand for therapy services and scarce resources [1]. The use of interactive video games as a therapy tool for addressing both physical and cognitive function is a growing trend in the health and aged care sector [2]. There are thought to be several benefits evident in using video games in therapy. Firstly, while traditional therapy programs may suffer from poor compliance rates, video game activities are designed to be fun and motivating and therefore may increase the amount of time the user spends in therapeutic activity [3]. Secondly, the activities are graded, structured and provide detailed feedback on perform
Constructivism in Practice: The Case for English Language Learners
Nyaradzo H. Mvududu,Jennifer Thiel-Burgess
International Journal of Education , 2012, DOI: 10.5296/ije.v4i3.2223
Abstract: A classroom of diverse learners with diverse language backgrounds can be a great challenge for a classroom teacher. English Language Learners (ELL) present a particular challenge to teachers as they represent such a wide range of academic abilities, English language abilities, and academic background. Constructivism is widely touted as an approach to probe for children’s level of understanding and the ways in which that understanding can be taken to higher level thinking. Constructivism is a way of learning and thinking. It is how students make sense of the material and how they can be taught most effectively. Constructivism as an educational theory holds that teachers should take into account what students know. Teachers then build on this knowledge and allow students to put their knowledge into practice. This paper will explore how the theory of constructivism may benefit ELL students in an inclusive classroom.
Illusory Upward Self-Motion Results in a Decrease in Perceived Room Temperature  [PDF]
Takeharu Seno, George H. Van Doorn
Psychology (PSYCH) , 2013, DOI: 10.4236/psych.2013.411118

Purpose: Stationary observers often experience illusory self-motion (vection) when they are exposed to large patterns of optic flow. The effect of different temperatures on the strength of vection was investigated. Method: Eleven participants were exposed to visual stimuli that induced illusory motion (up, down) in three room temperatures (26°C - 27°C, 21°C - 22°C, 5°C - 6°C). Participants rated (a) the vection magnitude, and (b) the room temperature (twice; before and after vection). Results: Upward vection was rated as stronger than downward vection in the 26°C - 27°C temperature. In addition, after experiencing upward and downward vection, subjective ratings of room temperature decreased and increased, respectively, when the room temperature was 26°C - 27°C. This effect was not observed when the room was 5°C - 6°C. Conclusion: These results suggest that a cross modal association exists between the direction “up” and 26°C - 27°C temperatures.

Air Pollution in Major Chinese Cities: Some Progress, But Much More to Do  [PDF]
Dorrit H. Lowsen, George A. Conway
Journal of Environmental Protection (JEP) , 2016, DOI: 10.4236/jep.2016.713162
Abstract: Background: Ambient (outdoor) air pollution has been implicated as a major cause of acute cardiovascular and pulmonary illnesses and increased risk for acute and chronic effects after chronic exposures, including mortality and morbidity. In 2008, due to persistent health concerns about its workforce and their dependents, the US Mission in China began monitoring air quality at the US Embassy in Beijing. Subsequently, monitoring stations were also established at US consulates at Shanghai (2011), Guangzhou (2011), Chengdu (2012), and Shenyang (2013). Objectives: To determine whether there have been definable trends in air quality in these five Chinese cities. Methods: Air monitoring results from each locale for accumulated PM2.5 particulate matter were calculated hourly. Accumulated data were organized, culled using a standardized set of heuristics, and analyzed for trends. Results: China’s capital city, Beijing, experienced decreased PM2.5 from 2013 through 2015, but no significant long-term downward trend from 2008 through 2015. Shanghai has not shown any definable air quality trend since 2012. Chengdu experienced some improvement in air quality since 2013, but none discernible from 2012 through 2015. Guangzhou had generally better air quality, and a downward trend since 2012. Shenyang experienced increasingly severe air pollution from 2013 through 2015. Conclusion: There appear to have been recent tangible, though modest, improvements in air quality in three large Chinese cities: Beijing, Chengdu, and Guangzhou, but no apparent progress in Shanghai, and a worrisome decline in air quality observed in Shenyang. Despite recent progress, there is a long way to go before even the cities which show improvement reach Chinese standards.
Direct evidence for coastal iodine particles from Laminaria macroalgae – linkage to emissions of molecular iodine
G. McFiggans,H. Coe,R. Burgess,J. Allan
Atmospheric Chemistry and Physics Discussions , 2004,
Abstract: Renewal of ultrafine aerosols in the marine boundary layer may lead to repopulation of the marine distribution and ultimately determine the concentration of cloud condensation nuclei (CCN). Thus the formation of nanometre-scale particles can lead to enhanced scattering of incoming radiation and a net cooling of the atmosphere. The recent demonstration of the chamber formation of new particles from the photolytic production of condensable iodine-containing compounds from diiodomethane (CH2I2), (O'Dowd et al., 2002; Kolb, 2002; Jimenez et al., 2003a; Burkholder and Ravishankara, 2003), provides an additional mechanism to the gas-to-particle conversion of sulphuric acid formed in the photo-oxidation of dimethylsulphide for marine aerosol repopulation. CH2I2 is emitted from seaweeds (Carpenter et al., 1999, 2000) and has been suggested as an initiator of particle formation. We demonstrate here for the first time that ultrafine iodine-containing particles are produced by intertidal macroalgae exposed to ambient levels of ozone. The particle composition is very similar both to those formed in the chamber photo-oxidation of diiodomethane and in the oxidation of molecular iodine by ozone. The particles formed in all three systems are similarly aspherical and behave alike when exposed to increased humidity environments. Direct coastal boundary layer observations of molecular iodine, ultrafine particle production and iodocarbons are reported. Using a newly measured molecular iodine photolysis rate, it is shown that, if atomic iodine is involved in the observed particle bursts, it is of the order of at least 1000 times more likely to result from molecular iodine photolysis than diiodomethane photolysis. A hypothesis for molecular iodine release from intertidal macroalgae is presented and the potential importance of macroalgal iodine particles in their contribution to CCN and global radiative forcing are discussed.
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