Matching Items (120)
Description

Background: The shift from solitary to social behavior is one of the major evolutionary transitions. Primitively eusocial bumblebees are uniquely placed to illuminate the evolution of highly eusocial insect societies. Bumblebees are also invaluable natural and agricultural pollinators, and there is widespread concern over recent population declines in some species. High-quality

Background: The shift from solitary to social behavior is one of the major evolutionary transitions. Primitively eusocial bumblebees are uniquely placed to illuminate the evolution of highly eusocial insect societies. Bumblebees are also invaluable natural and agricultural pollinators, and there is widespread concern over recent population declines in some species. High-quality genomic data will inform key aspects of bumblebee biology, including susceptibility to implicated population viability threats.

Results: We report the high quality draft genome sequences of Bombus terrestris and Bombus impatiens, two ecologically dominant bumblebees and widely utilized study species. Comparing these new genomes to those of the highly eusocial honeybee Apis mellifera and other Hymenoptera, we identify deeply conserved similarities, as well as novelties key to the biology of these organisms. Some honeybee genome features thought to underpin advanced eusociality are also present in bumblebees, indicating an earlier evolution in the bee lineage. Xenobiotic detoxification and immune genes are similarly depauperate in bumblebees and honeybees, and multiple categories of genes linked to social organization, including development and behavior, show high conservation. Key differences identified include a bias in bumblebee chemoreception towards gustation from olfaction, and striking differences in microRNAs, potentially responsible for gene regulation underlying social and other traits.

Conclusions: These two bumblebee genomes provide a foundation for post-genomic research on these key pollinators and insect societies. Overall, gene repertoires suggest that the route to advanced eusociality in bees was mediated by many small changes in many genes and processes, and not by notable expansion or depauperation.

ContributorsSadd, Ben M. (Author) / Barribeau, Seth M. (Author) / Bloch, Guy (Author) / de Graaf, Dirk C. (Author) / Dearden, Peter (Author) / Elsik, Christine G. (Author) / Gadau, Juergen (Author) / Grimmelikhuijzen, Cornelis J. P. (Author) / Hasselmann, Martin (Author) / Lozier, Jeffrey D. (Author) / Robertson, Hugh M. (Author) / Smagghe, Guy (Author) / Stolle, Eckart (Author) / Van Vaerenbergh, Matthias (Author) / Waterhouse, Robert M. (Author) / Bornberg-Bauer, Erich (Author) / Klasberg, Steffen (Author) / Bennett, Anna K. (Author) / Camara, Francisco (Author) / Guigo, Roderic (Author) / Hoff, Katharina (Author) / Mariotti, Marco (Author) / Munoz-Torres, Monica (Author) / Murphy, Terence (Author) / Santesmasses, Didac (Author) / Amdam, Gro (Author) / Beckers, Matthew (Author) / Beye, Martin (Author) / Biewer, Matthias (Author) / Bitondi, Marcia MG (Author) / Blaxter, Mark L. (Author) / Bourke, Andrew FG (Author) / Brown, Mark JF (Author) / Buechel, Severine D. (Author) / Cameron, Rossanah (Author) / Cappelle, Kaat (Author) / Carolan, James C. (Author) / Christiaens, Olivier (Author) / Ciborowski, Kate L. (Author) / Clarke, David F. (Author) / Colgan, Thomas J. (Author) / Collins, David H. (Author) / Cridge, Andrew G. (Author) / Dalmay, Tamas (Author) / Dreier, Stephanie (Author) / du Plessis, Louis (Author) / Duncan, Elizabeth (Author) / Erler, Silvio (Author) / Evans, Jay (Author) / Falcon, Talgo (Author) / Flores, Kevin (Author) / Freitas, Flavia CP (Author) / Fuchikawa, Taro (Author) / Gempe, Tanja (Author) / Hartfelder, Klaus (Author) / Hauser, Frank (Author) / Helbing, Sophie (Author) / Humann, Fernanda (Author) / Irvine, Frano (Author) / Jermiin, Lars S (Author) / Johnson, Claire E. (Author) / Johnson, Reed M (Author) / Jones, Andrew K. (Author) / Kadowaki, Tatsuhiko (Author) / Kidner, Jonathan H. (Author) / Koch, Vasco (Author) / Kohler, Arian (Author) / Kraus, F. Bernhard (Author) / Lattorff, H. Michael G. (Author) / Leask, Megan (Author) / Lockett, Gabrielle A. (Author) / Mallon, Eamonn B. (Author) / Marco Antonio, David S. (Author) / Marxer, Monika (Author) / Meeus, Ivan (Author) / Moritz, Robin FA (Author) / Nair, Ajay (Author) / Napflin, Kathrin (Author) / Nissen, Inga (Author) / Niu, Jinzhi (Author) / Nunes, Francis MF (Author) / Oakeshott, John G. (Author) / Osborne, Amy (Author) / Otte, Marianne (Author) / Pinheiro, Daniel G. (Author) / Rossie, Nina (Author) / Rueppell, Olav (Author) / Santos, Carolina G (Author) / Schmid-Hempel, Regula (Author) / Schmitt, Bjorn D. (Author) / Schulte, Christina (Author) / Simoes, Zila LP (Author) / Soares, Michelle PM (Author) / Swevers, Luc (Author) / Winnebeck, Eva C. (Author) / Wolschin, Florian (Author) / Yu, Na (Author) / Zdobnov, Evgeny M (Author) / Aqrawi, Peshtewani K (Author) / Blakenburg, Kerstin P (Author) / Coyle, Marcus (Author) / Francisco, Liezl (Author) / Hernandez, Alvaro G. (Author) / Holder, Michael (Author) / Hudson, Matthew E. (Author) / Jackson, LaRonda (Author) / Jayaseelan, Joy (Author) / Joshi, Vandita (Author) / Kovar, Christie (Author) / Lee, Sandra L. (Author) / Mata, Robert (Author) / Mathew, Tittu (Author) / Newsham, Irene F. (Author) / Ngo, Robin (Author) / Okwuonu, Geoffrey (Author) / Pham, Christopher (Author) / Pu, Ling-Ling (Author) / Saada, Nehad (Author) / Santibanez, Jireh (Author) / Simmons, DeNard (Author) / Thornton, Rebecca (Author) / Venkat, Aarti (Author) / Walden, Kimberly KO (Author) / Wu, Yuan-Qing (Author) / Debyser, Griet (Author) / Devreese, Bart (Author) / Asher, Claire (Author) / Blommaert, Julie (Author) / Chipman, Ariel D. (Author) / Chittka, Lars (Author) / Fouks, Bertrand (Author) / Liu, Jisheng (Author) / O'Neill, Meaghan P (Author) / Sumner, Seirian (Author) / Puiu, Daniela (Author) / Qu, Jiaxin (Author) / Salzberg, Steven L (Author) / Scherer, Steven E (Author) / Muzny, Donna M. (Author) / Richards, Stephen (Author) / Robinson, Gene E (Author) / Gibbs, Richard A. (Author) / Schmid-Hempel, Paul (Author) / Worley, Kim C (Author) / College of Liberal Arts and Sciences (Contributor)
Created2015-04-24
153290-Thumbnail Image.png
Description
Pre-Exposure Prophylaxis (PrEP) is any medical or public health procedure used before exposure to the disease causing agent, its purpose is to prevent, rather than treat or cure a disease. Most commonly, PrEP refers to an experimental HIV-prevention strategy that would use antiretrovirals to protect HIV-negative people from HIV infection.

Pre-Exposure Prophylaxis (PrEP) is any medical or public health procedure used before exposure to the disease causing agent, its purpose is to prevent, rather than treat or cure a disease. Most commonly, PrEP refers to an experimental HIV-prevention strategy that would use antiretrovirals to protect HIV-negative people from HIV infection. A deterministic mathematical model of HIV transmission is developed to evaluate the public-health impact of oral PrEP interventions, and to compare PrEP effectiveness with respect to different evaluation methods. The effects of demographic, behavioral, and epidemic parameters on the PrEP impact are studied in a multivariate sensitivity analysis. Most of the published models on HIV intervention impact assume that the number of individuals joining the sexually active population per year is constant or proportional to the total population. In the second part of this study, three models are presented and analyzed to study the PrEP intervention, with constant, linear, and logistic recruitment rates. How different demographic assumptions can affect the evaluation of PrEP is studied. When provided with data, often least square fitting or similar approaches can be used to determine a single set of approximated parameter values that make the model fit the data best. However, least square fitting only provides point estimates and does not provide information on how strongly the data supports these particular estimates. Therefore, in the third part of this study, Bayesian parameter estimation is applied on fitting ODE model to the related HIV data. Starting with a set of prior distributions for the parameters as initial guess, Bayes' formula can be applied to obtain a set of posterior distributions for the parameters which makes the model fit the observed data best. Evaluating the posterior distribution often requires the integration of high-dimensional functions, which is usually difficult to calculate numerically. Therefore, the Markov chain Monte Carlo (MCMC) method is used to approximate the posterior distribution.
ContributorsZhao, Yuqin (Author) / Kuang, Yang (Thesis advisor) / Taylor, Jesse (Committee member) / Armbruster, Dieter (Committee member) / Tang, Wenbo (Committee member) / Kang, Yun (Committee member) / Arizona State University (Publisher)
Created2014
152943-Thumbnail Image.png
Description
In a 2004 paper, John Nagy raised the possibility of the existence of a hypertumor \emph{i.e.}, a focus of aggressively reproducing parenchyma cells that invade part or all of a tumor. His model used a system of nonlinear ordinary differential equations to find a suitable set of conditions for which

In a 2004 paper, John Nagy raised the possibility of the existence of a hypertumor \emph{i.e.}, a focus of aggressively reproducing parenchyma cells that invade part or all of a tumor. His model used a system of nonlinear ordinary differential equations to find a suitable set of conditions for which these hypertumors exist. Here that model is expanded by transforming it into a system of nonlinear partial differential equations with diffusion, advection, and a free boundary condition to represent a radially symmetric tumor growth. Two strains of parenchymal cells are incorporated; one forming almost the entirety of the tumor while the much more aggressive strain

appears in a smaller region inside of the tumor. Simulations show that if the aggressive strain focuses its efforts on proliferating and does not contribute to angiogenesis signaling when in a hypoxic state, a hypertumor will form. More importantly, this resultant aggressive tumor is paradoxically prone to extinction and hypothesize is the cause of necrosis in many vascularized tumors.
ContributorsAlvarez, Roberto L (Author) / Milner, Fabio A (Thesis advisor) / Nagy, John D. (Committee member) / Kuang, Yang (Committee member) / Thieme, Horst (Committee member) / Mahalov, Alex (Committee member) / Smith, Hal (Committee member) / Arizona State University (Publisher)
Created2014
128710-Thumbnail Image.png
Description

Deforestation in Myanmar has recently attracted much attention worldwide. This study examined spatio-temporal patterns of deforestation and forest carbon flux in Myanmar from 2001 to 2010 and environmental impacts at the regional scale using land products of the Moderate Resolution Imaging Spectroradiometer (MODIS). The results suggest that the total deforestation

Deforestation in Myanmar has recently attracted much attention worldwide. This study examined spatio-temporal patterns of deforestation and forest carbon flux in Myanmar from 2001 to 2010 and environmental impacts at the regional scale using land products of the Moderate Resolution Imaging Spectroradiometer (MODIS). The results suggest that the total deforestation area in Myanmar was 21,178.8 km2, with an annual deforestation rate of 0.81%, and that the total forest carbon release was 20.06 million tons, with an annual rate of 0.37%. Mangrove forests had the highest deforestation and carbon release rates, and deciduous forests had both the largest deforestation area and largest amount of carbon release. During the study period, the south and southwestern regions of Myanmar, especially Ayeyarwady and Rakhine, were deforestation hotspots (i.e., the highest deforestation and carbon release rates occurred in these regions). Deforestation caused significant carbon release, reduced evapotranspiration (ET), and increased land surface temperatures (LSTs) in deforested areas in Myanmar during the study period. Constructive policy recommendations are put forward based on these research results.

ContributorsWang, Chuyuan (Author) / Myint, Soe (Author) / College of Liberal Arts and Sciences (Contributor)
Created2016-09-02
128653-Thumbnail Image.png
Description

This paper reviews how remotely sensed data have been used to understand the impact of urbanization on global environmental change. We describe how these studies can support the policy and science communities’ increasing need for detailed and up-to-date information on the multiple dimensions of cities, including their social, biological, physical,

This paper reviews how remotely sensed data have been used to understand the impact of urbanization on global environmental change. We describe how these studies can support the policy and science communities’ increasing need for detailed and up-to-date information on the multiple dimensions of cities, including their social, biological, physical, and infrastructural characteristics. Because the interactions between urban and surrounding areas are complex, a synoptic and spatial view offered from remote sensing is integral to measuring, modeling, and understanding these relationships. Here we focus on three themes in urban remote sensing science: mapping, indices, and modeling. For mapping we describe the data sources, methods, and limitations of mapping urban boundaries, land use and land cover, population, temperature, and air quality. Second, we described how spectral information is manipulated to create comparative biophysical, social, and spatial indices of the urban environment. Finally, we focus how the mapped information and indices are used as inputs or parameters in models that measure changes in climate, hydrology, land use, and economics.

ContributorsWentz, Elizabeth (Author) / Anderson, Sharolyn (Author) / Fragkias, Michail (Author) / Netzband, Maik (Author) / Mesev, Victor (Author) / Myint, Soe (Author) / Quattrochi, Dale (Author) / Rahman, Atiqur (Author) / Seto, Karen C. (Author) / College of Liberal Arts and Sciences (Contributor)
Created2014-04-30
128657-Thumbnail Image.png
Description

This study examines the spatial and temporal patterns of the surface urban heat island (SUHI) intensity in the Phoenix metropolitan area and the relationship with land use land cover (LULC) change between 2000 and 2014. The objective is to identify specific regions in Phoenix that have been increasingly heated and

This study examines the spatial and temporal patterns of the surface urban heat island (SUHI) intensity in the Phoenix metropolitan area and the relationship with land use land cover (LULC) change between 2000 and 2014. The objective is to identify specific regions in Phoenix that have been increasingly heated and cooled to further understand how LULC change influences the SUHI intensity. The data employed include MODerate-resolution Imaging Spectroradiometer (MODIS) land surface temperature (LST) 8-day composite June imagery, and classified LULC maps generated using 2000 and 2014 Landsat imagery. Results show that the regions that experienced the most significant LST changes during the study period are primarily on the outskirts of the Phoenix metropolitan area for both daytime and nighttime. The conversion to urban, residential, and impervious surfaces from all other LULC types has been identified as the primary cause of the UHI effect in Phoenix. Vegetation cover has been shown to significantly lower LST for both daytime and nighttime due to its strong cooling effect by producing more latent heat flux and less sensible heat flux. We suggest that urban planners, decision-makers, and city managers formulate new policies and regulations that encourage residential, commercial, and industrial developers to include more vegetation when planning new construction.

ContributorsWang, Chuyuan (Author) / Myint, Soe (Author) / Wang, Zhi-Hua (Author) / Song, Jiyun (Author) / College of Liberal Arts and Sciences (Contributor)
Created2016-02-26
128663-Thumbnail Image.png
Description

The urban heat island (UHI) phenomenon is a significant worldwide problem caused by rapid population growth and associated urbanization. The UHI effect exacerbates heat waves during the summer, increases energy and water consumption, and causes the high risk of heat-related morbidity and mortality. UHI mitigation efforts have increasingly relied on

The urban heat island (UHI) phenomenon is a significant worldwide problem caused by rapid population growth and associated urbanization. The UHI effect exacerbates heat waves during the summer, increases energy and water consumption, and causes the high risk of heat-related morbidity and mortality. UHI mitigation efforts have increasingly relied on wisely designing the urban residential environment such as using high albedo rooftops, green rooftops, and planting trees and shrubs to provide canopy coverage and shading. Thus, strategically designed residential rooftops and their surrounding landscaping have the potential to translate into significant energy, long-term cost savings, and health benefits. Rooftop albedo, material, color, area, slope, height, aspect and nearby landscaping are factors that potentially contribute. To extract, derive, and analyze these rooftop parameters and outdoor landscaping information, high resolution optical satellite imagery, LIDAR (light detection and ranging) point clouds and thermal imagery are necessary. Using data from the City of Tempe AZ (a 2010 population of 160,000 people), we extracted residential rooftop footprints and rooftop configuration parameters from airborne LIDAR point clouds and QuickBird satellite imagery (2.4 m spatial resolution imagery). Those parameters were analyzed against surface temperature data from the MODIS/ASTER airborne simulator (MASTER). MASTER images provided fine resolution (7 m) surface temperature data for residential areas during daytime and night time. Utilizing these data, ordinary least squares (OLS) regression was used to evaluate the relationships between residential building rooftops and their surface temperature in urban environment. The results showed that daytime rooftop temperature was closely related to rooftop spectral attributes, aspect, slope, and surrounding trees. Night time temperature was only influenced by rooftop spectral attributes and slope.

ContributorsZhao, Qunshan (Author) / Myint, Soe (Author) / Wentz, Elizabeth (Author) / Fan, Chao (Author) / College of Liberal Arts and Sciences (Contributor)
Created2015-09-18
128685-Thumbnail Image.png
Description

Predicting the timing of a castrate resistant prostate cancer is critical to lowering medical costs and improving the quality of life of advanced prostate cancer patients. We formulate, compare and analyze two mathematical models that aim to forecast future levels of prostate-specific antigen (PSA). We accomplish these tasks by employing

Predicting the timing of a castrate resistant prostate cancer is critical to lowering medical costs and improving the quality of life of advanced prostate cancer patients. We formulate, compare and analyze two mathematical models that aim to forecast future levels of prostate-specific antigen (PSA). We accomplish these tasks by employing clinical data of locally advanced prostate cancer patients undergoing androgen deprivation therapy (ADT). While these models are simplifications of a previously published model, they fit data with similar accuracy and improve forecasting results. Both models describe the progression of androgen resistance. Although Model 1 is simpler than the more realistic Model 2, it can fit clinical data to a greater precision. However, we found that Model 2 can forecast future PSA levels more accurately. These findings suggest that including more realistic mechanisms of androgen dynamics in a two population model may help androgen resistance timing prediction.

ContributorsBaez, Javier (Author) / Kuang, Yang (Author) / College of Liberal Arts and Sciences (Contributor)
Created2016-11-16
141494-Thumbnail Image.png
Description

Background:
Data assimilation refers to methods for updating the state vector (initial condition) of a complex spatiotemporal model (such as a numerical weather model) by combining new observations with one or more prior forecasts. We consider the potential feasibility of this approach for making short-term (60-day) forecasts of the growth and

Background:
Data assimilation refers to methods for updating the state vector (initial condition) of a complex spatiotemporal model (such as a numerical weather model) by combining new observations with one or more prior forecasts. We consider the potential feasibility of this approach for making short-term (60-day) forecasts of the growth and spread of a malignant brain cancer (glioblastoma multiforme) in individual patient cases, where the observations are synthetic magnetic resonance images of a hypothetical tumor.

Results:
We apply a modern state estimation algorithm (the Local Ensemble Transform Kalman Filter), previously developed for numerical weather prediction, to two different mathematical models of glioblastoma, taking into account likely errors in model parameters and measurement uncertainties in magnetic resonance imaging. The filter can accurately shadow the growth of a representative synthetic tumor for 360 days (six 60-day forecast/update cycles) in the presence of a moderate degree of systematic model error and measurement noise.

Conclusions:
The mathematical methodology described here may prove useful for other modeling efforts in biology and oncology. An accurate forecast system for glioblastoma may prove useful in clinical settings for treatment planning and patient counseling.

ContributorsKostelich, Eric (Author) / Kuang, Yang (Author) / McDaniel, Joshua (Author) / Moore, Nina Z. (Author) / Martirosyan, Nikolay L. (Author) / Preul, Mark C. (Author) / College of Liberal Arts and Sciences (Contributor)
Created2011-12-21
137847-Thumbnail Image.png
Description
Glioblastoma multiforme (GBMs) is the most prevalent brain tumor type and causes approximately 40% of all non-metastic primary tumors in adult patients [1]. GBMs are malignant, grade-4 brain tumors, the most aggressive classication as established by the World Health Organization and are marked by their low survival rate; the median

Glioblastoma multiforme (GBMs) is the most prevalent brain tumor type and causes approximately 40% of all non-metastic primary tumors in adult patients [1]. GBMs are malignant, grade-4 brain tumors, the most aggressive classication as established by the World Health Organization and are marked by their low survival rate; the median survival time is only twelve months from initial diagnosis: Patients who live more than three years are considered long-term survivors [2]. GBMs are highly invasive and their diffusive growth pattern makes it impossible to remove the tumors by surgery alone [3]. The purpose of this paper is to use individual patient data to parameterize a model of GBMs that allows for data on tumor growth and development to be captured on a clinically relevant time scale. Such an endeavor is the rst step to a clinically applicable predictions of GBMs. Previous research has yielded models that adequately represent the development of GBMs, but they have not attempted to follow specic patient cases through the entire tumor process. Using the model utilized by Kostelich et al. [4], I will attempt to redress this deciency. In doing so, I will improve upon a family of models that can be used to approximate the time of development and/or structure evolution in GBMs. The eventual goal is to incorporate Magnetic Resonance Imaging (MRI) data into a parameterized model of GBMs in such a way that it can be used clinically to predict tumor growth and behavior. Furthermore, I hope to come to a denitive conclusion as to the accuracy of the Koteslich et al. model throughout the development of GBMs tumors.
ContributorsManning, Miles (Author) / Kostelich, Eric (Thesis director) / Kuang, Yang (Committee member) / Preul, Mark (Committee member) / Barrett, The Honors College (Contributor) / College of Liberal Arts and Sciences (Contributor)
Created2012-12