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Spread Of Domestic Animals Across Neolithic Western Anatolia: New Stable Isotope Evidence From Ugurlu Höyük, The Island Of Gökçeada, Turkey, Suzanne E. Pilaar Birch, Levent Atici, Burcin Erdogu Oct 2019

Spread Of Domestic Animals Across Neolithic Western Anatolia: New Stable Isotope Evidence From Ugurlu Höyük, The Island Of Gökçeada, Turkey, Suzanne E. Pilaar Birch, Levent Atici, Burcin Erdogu

Anthropology Faculty Research

The origins of agriculture in Southwest Asia over 10,000 years ago and its subsequent spread into Europe during the Neolithic have been the focus of much archaeological research over the past several decades. Increasingly more sophisticated analytical techniques have allowed for better understanding of the complex interactions that occurred amongst humans, animals, and their environments during this transition. The Aegean Islands are critically situated where Anatolia and the mainland Greece meet, making the region pivotal for understanding the movement of the Neolithic into Europe. Located on the largest Turkish Aegean island of Gökçeada, the site of Uğurlu Höyük dates to …

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Reproduction And Dispersal Of Biological Soil Crust Organisms, Steven D. Warren, Larry L. St. Clair, Lloyd R. Stark, Louise A. Lewis, Nuttapon Pombubpa, Tania Kurbessoian, Jason E. Stajich, Zachary T. Aanderud Oct 2019

Reproduction And Dispersal Of Biological Soil Crust Organisms, Steven D. Warren, Larry L. St. Clair, Lloyd R. Stark, Louise A. Lewis, Nuttapon Pombubpa, Tania Kurbessoian, Jason E. Stajich, Zachary T. Aanderud

Life Sciences Faculty Research

Biological soil crusts (BSCs) consist of a diverse and highly integrated community of organisms that effectively colonize and collectively stabilize soil surfaces. BSCs vary in terms of soil chemistry and texture as well as the environmental parameters that combine to support unique combinations of organisms—including cyanobacteria dominated, lichen-dominated, and bryophyte-dominated crusts. The list of organismal groups that make up BSC communities in various and unique combinations include—free living, lichenized, and mycorrhizal fungi, chemoheterotrophic bacteria, cyanobacteria, diazotrophic bacteria and archaea, eukaryotic algae, and bryophytes. The various BSC organismal groups demonstrate several common characteristics including—desiccation and extreme temperature tolerance, production of various …

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Relativistic Astronomy. Iii. Test Of Special Relativity Via Doppler Effect, Yuan-Pei Yang, Jin-Peng Zhu, Bing Zhang Sep 2019

Relativistic Astronomy. Iii. Test Of Special Relativity Via Doppler Effect, Yuan-Pei Yang, Jin-Peng Zhu, Bing Zhang

Physics & Astronomy Faculty Research

The "Breakthrough Starshot" program is planning to send transrelativistic probes to travel to nearby stellar systems within decades. Because the probe velocity is designed to be a good fraction of the light speed, Zhang & Li recently proposed that these transrelativistic probes can be used to study astronomical objects and to test special relativity. In this work, we propose some methods to test special relativity and constrain photon mass using the Doppler effect with the images and spectral features of astronomical objects as observed in the transrelativistic probes. We introduce more general theories to set up the framework of testing …

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A Global View Of The Inner Accretion And Ejection Flow Around Super Massive Black Holes, Margherita Giustini, Daniel Proga Sep 2019

A Global View Of The Inner Accretion And Ejection Flow Around Super Massive Black Holes, Margherita Giustini, Daniel Proga

Physics & Astronomy Faculty Research

Context. Understanding the physics and geometry of accretion and ejection around super massive black holes (SMBHs) is important to understand the evolution of active galactic nuclei (AGN) and therefore of the large scale structures of the Universe. Aims. We aim at providing a simple, coherent, and global view of the sub-parsec accretion and ejection flow in AGN with varying Eddington ratio, ṁ, and black hole mass, MBH. Methods. We made use of theoretical insights, results of numerical simulations, as well as UV and X-ray observations to review the inner regions of AGN by including different accretion and ejection modes, with …

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Numerical Simulation Based Targeting Of The Magushan Skarn Cu-Mo Deposit, Middle-Lower Yangtze Metallogenic Belt, China, Xunyu Hu, Xiaohui Li, Feng Yuan, Alison Ord, Simon M. Jowitt, Yue Li, Wenqiang Dai, Rui Ye, Taofa Zhou Sep 2019

Numerical Simulation Based Targeting Of The Magushan Skarn Cu-Mo Deposit, Middle-Lower Yangtze Metallogenic Belt, China, Xunyu Hu, Xiaohui Li, Feng Yuan, Alison Ord, Simon M. Jowitt, Yue Li, Wenqiang Dai, Rui Ye, Taofa Zhou

Geoscience Faculty Research

The Magushan Cu–Mo deposit is a skarn deposit within the Nanling–Xuancheng mining district of the Middle-Lower Yangtze River Metallogenic Belt (MLYRMB), China. This study presents the results of a new numerical simulation that models the ore-forming processes that generated the Magushan deposit and enables the identification of unexplored areas that have significant exploration potential under areas covered by thick sedimentary sequences that cannot be easily explored using traditional methods. This study outlines the practical value of numerical simulation in determining the processes that operate during mineral deposit formation and how this knowledge can be used to enhance exploration targeting in …

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Polar Alignment Of A Protoplanetary Disc Around An Eccentric Binary – Iii. Effect Of Disc Mass, Rebecca G. Martin, Stephen H. Lubow Sep 2019

Polar Alignment Of A Protoplanetary Disc Around An Eccentric Binary – Iii. Effect Of Disc Mass, Rebecca G. Martin, Stephen H. Lubow

Physics & Astronomy Faculty Research

An initially sufficiently misaligned low-mass protoplanetary disc around an eccentric binary undergoes damped nodal oscillations of tilt angle and longitude of ascending node. Dissipation causes evolution towards a stationary state of polar alignment in which the disc lies perpendicular to the binary orbital plane with angular momentum aligned to the eccentricity vector of the binary. We use hydrodynamic simulations and analytical methods to investigate how the mass of the disc affects this process. The simulations suggest that a disc with non-zero mass settles into a stationary state in the frame of the binary, the generalized polar state, at somewhat lower …

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Beyond Cumulative Sum Charting In Non-Stationarity Detection And Estimation, Felix Zhan, Anthony Martinez, Nilab Rai, Richard Mcconnell, Matthew Swan, Moinak Bhaduri, Justin Zhan, Laxmi Gewali, Paul Oh Sep 2019

Beyond Cumulative Sum Charting In Non-Stationarity Detection And Estimation, Felix Zhan, Anthony Martinez, Nilab Rai, Richard Mcconnell, Matthew Swan, Moinak Bhaduri, Justin Zhan, Laxmi Gewali, Paul Oh

Computer Science Faculty Research

In computer science, stochastic processes, and industrial engineering, stationarity is often taken to imply a stable, predictable flow of events and non-stationarity, consequently, a departure from such a flow. Efficient detection and accurate estimation of non-stationarity are crucial in understanding the evolution of the governing dynamics. Pragmatic considerations include protecting human lives and property in the context of devastating processes such as earthquakes or hurricanes. Cumulative Sum (CUSUM) charting, the prevalent technique to weed out such non-stationarities, suffers from assumptions on a priori knowledge of the pre and post-change process parameters and constructs such as time discretization. In this paper, …

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Huawei, Bis, And The Ieee: It's Déjà Vu All Over Again, Hal Berghel Sep 2019

Huawei, Bis, And The Ieee: It's Déjà Vu All Over Again, Hal Berghel

Computer Science Faculty Research

No abstract provided.

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Fourth To Sixth Grade Teachers’ Invented Real World Problems And Pictorial Representations For Fraction Division, Travis Olson, Micah Stohlmann, Yichen Yang, Xing Huang Sep 2019

Fourth To Sixth Grade Teachers’ Invented Real World Problems And Pictorial Representations For Fraction Division, Travis Olson, Micah Stohlmann, Yichen Yang, Xing Huang

Teaching and Learning Faculty Research

Teaching fraction operations for conceptual understanding is a challenging task. For the topic of fraction division especially, teachers need support because teachers find this difficult to teach and elementary and middle school students struggle to learn this concept. Well-structured professional development can assist teachers in exploring their own understanding as well as how to incorporate multiple representations in their instruction. This naturalistic inquiry study investigated fourth to sixth grade teachers’ invented real-world problems and pictorial representations for fraction division. The teachers completed a written assessment focused on conceptual understanding of fraction operations through multiple representations at the beginning and conclusion …

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The Radial Distribution Of Dust Particles In The Hl Tau Disk From Alma And Vla Observations, Carlos Carrasco-Gonzalez, Anibal Sierra, Mario Flock, Zhaohuan Zhu, Thomas Henning, Claire Chandler, Roberto Galvan-Madrid, Enrique Macias, Guillem Anglada, Hendrik Linz, Mayra Osorio, Luis F. Rodriguez, Leonardo Testi, Jose M. Torrelles, Laura Perez, Yao Liu Sep 2019

The Radial Distribution Of Dust Particles In The Hl Tau Disk From Alma And Vla Observations, Carlos Carrasco-Gonzalez, Anibal Sierra, Mario Flock, Zhaohuan Zhu, Thomas Henning, Claire Chandler, Roberto Galvan-Madrid, Enrique Macias, Guillem Anglada, Hendrik Linz, Mayra Osorio, Luis F. Rodriguez, Leonardo Testi, Jose M. Torrelles, Laura Perez, Yao Liu

Physics & Astronomy Faculty Research

Understanding planet formation requires one to discern how dust grows in protoplanetary disks. An important parameter to measure in disks is the maximum dust grain size present. This is usually estimated through measurements of the dust opacity at different millimeter wavelengths assuming optically thin emission and dust opacity dominated by absorption. However, Atacama Large Millimeter/submillimeter Array (ALMA) observations have shown that these assumptions might not be correct in the case of protoplanetary disks, leading to overestimation of particle sizes and to underestimation of the disk's mass. Here, we present an analysis of high-quality ALMA and Very Large Array images of …

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Literature Review: Biocement For Stabilization Of Expansive Soils In Las Vegas, Nevada, Silva Topchyan, Moses Karakouzian Sep 2019

Literature Review: Biocement For Stabilization Of Expansive Soils In Las Vegas, Nevada, Silva Topchyan, Moses Karakouzian

LSAMP Poster Presentations

The aim of this study was to present a possibility for the use of biocementon expansive clay. Expansive soil is a type of clay when exposed to water and moisture changes its volume. Due to the clays swelling and shrinkage behavior itsdifficult to use it in engineering and construction projects, therefore costly and unhealthy techniques have been used to stabiliseexpansive soil in order to address the problem [12]. A possible healthy and environmentally friendly solution is Biocement which uses microbial induced calcite precipitation (MICP) in order to help aggregate soil to form a stable cementitiousmaterial. MICP isdependent on the innate …

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Treating Rapid Responses As Incorrect For Non-Timed Formative Tests, Daniel B. Wright Sep 2019

Treating Rapid Responses As Incorrect For Non-Timed Formative Tests, Daniel B. Wright

Educational Psychology, Leadership, and Higher Education Faculty Research

When students respond rapidly to an item during an assessment, it suggests that they may have guessed. Guessing adds error to ability estimates. Treating rapid responses as incorrect answers increases the accuracy of ability estimates for timed high-stakes summative tests like the ACT. There are fewer reasons to guess rapidly in non-timed formative tests, like those used as part of many personalized learning systems. Data from approximately 75 thousand formative assessments, from 777 students at two northern California charter high schools, were analyzed. The accuracy of ability estimates is only slightly improved by treating responses made in less than five …

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Gamma-Ray Bursts Induced By Turbulent Reconnection, A. Lazarian, Bing Zhang, Siyao Xu Sep 2019

Gamma-Ray Bursts Induced By Turbulent Reconnection, A. Lazarian, Bing Zhang, Siyao Xu

Physics & Astronomy Faculty Research

We revisit the Internal-Collision-induced MAgnetic Reconnection and Turbulence model of gamma-ray bursts (GRBs) in view of the advances made in understanding of both relativistic magnetic turbulence and relativistic turbulent magnetic reconnection. We identify the kink instability as the most natural way of changing the magnetic configuration to release the magnetic free energy through magnetic reconnection, as well as driving turbulence that enables fast turbulent reconnection. We show that this double role of the kink instability is important for explaining the prompt emission of GRBs. Our study confirms the critical role that turbulence plays in boosting reconnection efficiency in GRBs and …

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Photoionization Calculations Of The Radiation Force Due To Spectral Lines In Agns, Randall C. Dannen, Daniel Proga, Timothy R. Kallman, Tim Waters Sep 2019

Photoionization Calculations Of The Radiation Force Due To Spectral Lines In Agns, Randall C. Dannen, Daniel Proga, Timothy R. Kallman, Tim Waters

Physics & Astronomy Faculty Research

One of the main mechanisms that could drive mass outflows in active galactic nuclei (AGNs) is radiation pressure due to spectral lines. Although straightforward to understand, the actual magnitude of the radiation force is challenging to compute because the force depends on the physical conditions in the gas, as well as the strength, spectral energy distribution (SED), and geometry of the radiation field. We present results from our photoionization and radiation transfer calculations of the force multiplier, M(ξ, t), using the same radiation field to compute the gas photoionization and thermal balance. We assume low gas density (n = 104 …

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Closing The Nuclear Fuel Cycle With A Simplified Minor Actinide Lanthanide Separation Process (Alsep) And Additive Manufacturing, Artem V. Gelis, Peter Kozak, Andrew T. Breshears, M. Alex Brown, Cari Launiere, Emily L. Campbell, Gabreil B. Hall, Tatiana G. Levitskaia, Vanessa E. Holfeltz, Gregg J. Lumetta Sep 2019

Closing The Nuclear Fuel Cycle With A Simplified Minor Actinide Lanthanide Separation Process (Alsep) And Additive Manufacturing, Artem V. Gelis, Peter Kozak, Andrew T. Breshears, M. Alex Brown, Cari Launiere, Emily L. Campbell, Gabreil B. Hall, Tatiana G. Levitskaia, Vanessa E. Holfeltz, Gregg J. Lumetta

Chemistry and Biochemistry Faculty Research

Expanded low-carbon baseload power production through the use of nuclear fission can be enabled by recycling long-lived actinide isotopes within the nuclear fuel cycle. This approach provides the benefits of (a) more completely utilizing the energy potential of mined uranium, (b) reducing the footprint of nuclear geological repositories, and (c) reducing the time required for the radiotoxicity of the disposed waste to decrease to the level of uranium ore from one hundred thousand years to a few hundred years. A key step in achieving this goal is the separation of long-lived isotopes of americium (Am) and curium (Cm) for recycle …

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Nitric Oxide Is Involved In Heavy Ion-Induced Non-Targeted Effects In Human Fibroblasts, Megumi Hada, Premkumar B. Saganti, Francis A. Cucinotta Sep 2019

Nitric Oxide Is Involved In Heavy Ion-Induced Non-Targeted Effects In Human Fibroblasts, Megumi Hada, Premkumar B. Saganti, Francis A. Cucinotta

Health Physics and Diagnostic Sciences Faculty Research

Previously, we investigated the dose response for chromosomal aberration (CA) for exposures corresponding to less than one particle traversal per cell nucleus by high energy and charge (HZE) particles, and showed that the dose responses for simple exchanges for human fibroblast irradiated under confluent culture conditions were best fit by non-linear models motivated by a non-targeted effect (NTE). Our results suggested that the simple exchanges in normal human fibroblasts have an important NTE contribution at low particle fluence. Nitric oxide (NO) has been reported as a candidate for intercellular signaling for NTE in many studies. In order to estimate the …

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Limits On The Weak Equivalence Principle And Photon Mass With Frb 121102 Subpulses, Nan Xing, He Gao, Jun-Jie Wei, Zhengxiang Li, Weiyang Wang, Bing Zhang, Xue-Feng Wu, Peter Meszaros Sep 2019

Limits On The Weak Equivalence Principle And Photon Mass With Frb 121102 Subpulses, Nan Xing, He Gao, Jun-Jie Wei, Zhengxiang Li, Weiyang Wang, Bing Zhang, Xue-Feng Wu, Peter Meszaros

Physics & Astronomy Faculty Research

Fast radio bursts (FRBs) are short-duration (~millisecond) radio transients with cosmological origin. The simple sharp features of the FRB signal have been utilized to probe two fundamental laws of physics, namely, testing Einstein's weak equivalence principle and constraining the rest mass of the photon. Recently, Hessels et al. found that after correcting for dispersive delay, some of the bursts in FRB 121102 have complex time–frequency structures that include subpulses with a time–frequency downward drifting property. Using the delay time between subpulses in FRB 121102, here we show that the parameterized post-Newtonian parameter γ is the same for photons with different …

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A Nanoscale Investigation Of Carlin-Type Gold Deposits: An Atom-Scale Elemental And Isotopic Perspective, Philippe Gopon, James O. Douglas, Maria A. Auger, Lars Hansen, Jon Wade, Jean S. Cline, Laurence J. Robb, Michael P. Moody Sep 2019

A Nanoscale Investigation Of Carlin-Type Gold Deposits: An Atom-Scale Elemental And Isotopic Perspective, Philippe Gopon, James O. Douglas, Maria A. Auger, Lars Hansen, Jon Wade, Jean S. Cline, Laurence J. Robb, Michael P. Moody

Geoscience Faculty Research

Carlin-type gold deposits are one of the most important gold mineralization styles in the world. Despite their economic importance and the large volume of work that has been published, there remain crucial questions regarding their metallogenesis. Much of this uncertainty is due to the cryptic nature of the gold occurrence, with gold occurring as dispersed nanoscale inclusions within host pyrite rims that formed on earlier formed barren pyrite cores. The small size of the gold inclusions has made determining their nature within the host sulfides and the mechanisms by which they precipitated from the ore fluids particularly problematic. This study …

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Modifications Of The Cztse/Mo Back-Contact Interface By Plasma Treatments, Wenjin Chen, Teoman Taskesen, David Nowak, Ulf Mikolajczak, Mohamed H. Sayed, Devendra Pareek, Jorg Ohland, Thomas Schnabel, Erik Ahlswede, Dirk Hauschild, Lothar Weinhardt, Clemens Heske, Jurgen Parisi, Levent Gutay Aug 2019

Modifications Of The Cztse/Mo Back-Contact Interface By Plasma Treatments, Wenjin Chen, Teoman Taskesen, David Nowak, Ulf Mikolajczak, Mohamed H. Sayed, Devendra Pareek, Jorg Ohland, Thomas Schnabel, Erik Ahlswede, Dirk Hauschild, Lothar Weinhardt, Clemens Heske, Jurgen Parisi, Levent Gutay

Chemistry and Biochemistry Faculty Research

Molybdenum (Mo) is the most commonly used back-contact material for copper zinc tin selenide (CZTSe)-based thin-film solar cells. For most fabrication methods, an interfacial molybdenum diselenide (MoSe2) layer with an uncontrolled thickness is formed, ranging from a few tens of nm up to ≈1 μm. In order to improve the control of the back-contact interface in CZTSe solar cells, the formation of a MoSe2 layer with a homogeneous and defined thickness is necessary. In this study, we use plasma treatments on the as-grown Mo surface prior to the CZTSe absorber formation, which consists of the deposition of stacked metallic layers …

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Evaluating The Sustainability Of Indirect Potable Reuse And Direct Potable Reuse: A Southern Nevada Case Study, Sajjad Ahmad, Cory Dow, Krystyna Stave, Daniel Gerrity Aug 2019

Evaluating The Sustainability Of Indirect Potable Reuse And Direct Potable Reuse: A Southern Nevada Case Study, Sajjad Ahmad, Cory Dow, Krystyna Stave, Daniel Gerrity

Civil and Environmental Engineering and Construction Faculty Research

This case study presents a framework for evaluating the sustainability of indirect potable reuse (IPR) and direct potable reuse (DPR) in Las Vegas, Nevada. A system dynamics model was developed to simulate population growth, water supply, water quality, energy costs, net present worth (NPW), and greenhouse gas (GHG) emissions. The model confirmed that DPR could achieve a net reduction in energy costs of up to US$250 million while still ensuring an adequate water supply. However, the high NPW of DPR ($1.0–$4.0 billion) relative to the status quo IPR approach ($0.6 billion) represents a significant economic hurdle, although future monetization of …

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Space Telescope And Optical Reverberation Mapping Project. Viii. Time Variability Of Emission And Absorption In Ngc 5548 Based On Modeling The Ultraviolet Spectrum, Gerard A. Kriss, Gisella De Rosa, Justin Ely, Bradley M. Peterson, J. Kaastra, M. Mehdipour, Gary J. Ferland, Maryamossadat Dehghanian, S. Mathur, Rick Edelson, Kirk T. Korista, N. Arav, Aaron J. Barth, Misty C. Bentz, W. Niel Brandt, D. Michael Crenshaw, E. Dalla Bonta, K. D. Kenney, C. Done, Michael Eracleous, Michael M. Fausnaugh, E. Gardner, Michael R. Goad, Catherine J. Grier, Keith Horne, Christopher S. Kochanek, I. M. Mchardy, Hagai Netzer, Anna Pancoast, L. Pei, Richard W. Pogge, Daniel Proga Aug 2019

Space Telescope And Optical Reverberation Mapping Project. Viii. Time Variability Of Emission And Absorption In Ngc 5548 Based On Modeling The Ultraviolet Spectrum, Gerard A. Kriss, Gisella De Rosa, Justin Ely, Bradley M. Peterson, J. Kaastra, M. Mehdipour, Gary J. Ferland, Maryamossadat Dehghanian, S. Mathur, Rick Edelson, Kirk T. Korista, N. Arav, Aaron J. Barth, Misty C. Bentz, W. Niel Brandt, D. Michael Crenshaw, E. Dalla Bonta, K. D. Kenney, C. Done, Michael Eracleous, Michael M. Fausnaugh, E. Gardner, Michael R. Goad, Catherine J. Grier, Keith Horne, Christopher S. Kochanek, I. M. Mchardy, Hagai Netzer, Anna Pancoast, L. Pei, Richard W. Pogge, Daniel Proga

Physics & Astronomy Faculty Research

We model the ultraviolet spectra of the Seyfert 1 galaxy NGC 5548 obtained with the Hubble Space Telescope during the 6 month reverberation mapping campaign in 2014. Our model of the emission from NGC 5548 corrects for overlying absorption and deblends the individual emission lines. Using the modeled spectra, we measure the response to continuum variations for the deblended and absorption-corrected individual broad emission lines, the velocity-dependent profiles of Lyα and C iv, and the narrow and broad intrinsic absorption features. We find that the time lags for the corrected emission lines are comparable to those for the original data. …

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Implementation Of National Policies For A Total Asbestos Ban: A Global Comparison, Ro-Ting Lin Phd, Lung-Chang Chien Drph, Masamine Jimba Phd, Sugio Furuya Bec, Ken Takahashi Phd Aug 2019

Implementation Of National Policies For A Total Asbestos Ban: A Global Comparison, Ro-Ting Lin Phd, Lung-Chang Chien Drph, Masamine Jimba Phd, Sugio Furuya Bec, Ken Takahashi Phd

Environmental & Global Health Faculty Research

Background Two international Conventions from the International Labor Organization (ILO; C162 Asbestos Convention) and the UN (Basel Convention) offer governments guidelines for achieving a total asbestos ban policy, but the long-term effect of these Conventions on policy implementation, and the role of government effectiveness, remains unknown. We aimed to investigate associations between government ratification of the ILO and UN international Conventions, government effectiveness, and implementation of a national total asbestos ban. Methods We obtained data for year of a national asbestos ban, year of ratification of one or both international Conventions, and World Bank government effectiveness scores for 108 countries …

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Viewing Angle Constraints On S190425z And S190426c And The Joint Gravitational-Wave/Gamma-Ray Detection Fractions For Binary Neutron Star Mergers, Hao-Ran Song, Shun-Ke Ai, Min-Hao Wang, Nan Xing, He Gao, Bing Zhang Aug 2019

Viewing Angle Constraints On S190425z And S190426c And The Joint Gravitational-Wave/Gamma-Ray Detection Fractions For Binary Neutron Star Mergers, Hao-Ran Song, Shun-Ke Ai, Min-Hao Wang, Nan Xing, He Gao, Bing Zhang

Physics & Astronomy Faculty Research

The Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo scientific collaboration (LVC) detected two binary neutron star (BNS) merger candidates, S190425z and S190426c. The Fermi-Gamma-ray Burst Monitor (GBM) observed 55.6% (for S190425z) and 100% (for S190426c) of the probability regions of both events at the respective merger times, but no gamma-ray burst (GRB) was detected in either case. The derived luminosity upper limits suggest that a short GRB similar to GRB 170817A would not be detectable for both cases due to their distances, which are larger than that of GW170817. Assuming that the jet profile obtained from GW170817/GRB 170817A is quasi-universal …

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Type I Outbursts In Low-Eccentricity Be/X-Ray Binaries, Alessia Franchini, Rebecca G. Martin Aug 2019

Type I Outbursts In Low-Eccentricity Be/X-Ray Binaries, Alessia Franchini, Rebecca G. Martin

Physics & Astronomy Faculty Research

Type I outbursts in Be/X-ray binaries are usually associated with the eccentricity of the binary orbit. The neutron star accretes gas from the outer parts of the decretion disk around the Be star at each periastron passage. However, this mechanism cannot explain type I outbursts that have been observed in nearly circular orbit Be/X-ray binaries. With hydrodynamical simulations and analytic estimates we find that in a circular orbit binary, a nearly coplanar disk around the Be star can become eccentric. The extreme mass ratio of the binary leads to the presence of the 3:1 Lindblad resonance inside the Be star …

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The Frequency Of Kozai–Lidov Disc Oscillation Driven Giant Outbursts In Be/X-Ray Binaries, Rebecca G. Martin, Alessia Franchini Aug 2019

The Frequency Of Kozai–Lidov Disc Oscillation Driven Giant Outbursts In Be/X-Ray Binaries, Rebecca G. Martin, Alessia Franchini

Physics & Astronomy Faculty Research

Giant outbursts of Be/X-ray binaries may occur when a Be-star disc undergoes strong eccentricity growth due to the Kozai–Lidov (KL) mechanism. The KL effect acts on a disc that is highly inclined to the binary orbital plane provided that the disc aspect ratio is sufficiently small. The eccentric disc overflows its Roche lobe and material flows from the Be star disc over to the companion neutron star causing X-ray activity. With N-body simulations and steady state decretion disc models we explore system parameters for which a disc in the Be/X-ray binary 4U 0115+634 is KL unstable and the resulting time-scale …

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Response Of Human Small Intestinal Epithelium To Fractionated Irradiation: Dynamical Modeling Approach, Francis A. Cucinotta, Olga A. Smirnova Aug 2019

Response Of Human Small Intestinal Epithelium To Fractionated Irradiation: Dynamical Modeling Approach, Francis A. Cucinotta, Olga A. Smirnova

Health Physics and Diagnostic Sciences Faculty Research

A biologically motivated mathematical model of the dynamics of the small intestinal epithelium in humans treated with fractionated radiotherapy has been developed and is further investigated here. This model, originating from our previous work, is implemented as a system of nonlinear ordinary differential equations, in which the variables and parameters have a clear biological meaning. The model also includes, as input, the key parameters of fractionated irradiation. The modeling results on the dynamical response of the human normal small intestinal epithelium to fractionated radiation therapy regimens were in agreement with the corresponding empirical data, which, in turn, demonstrates the capability …

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Probing The Direct Factor For Superconductivity In Fese-Based Superconductors By Raman Scattering, Animin Zhang, Xiaoli Ma, Yimeng Wang, Shanshan Sun, Bin Lei, Hechang Lei, Xianhui Chen, Xiaoqun Wang, Changfeng Chen, Qingming Zhang Aug 2019

Probing The Direct Factor For Superconductivity In Fese-Based Superconductors By Raman Scattering, Animin Zhang, Xiaoli Ma, Yimeng Wang, Shanshan Sun, Bin Lei, Hechang Lei, Xianhui Chen, Xiaoqun Wang, Changfeng Chen, Qingming Zhang

Physics & Astronomy Faculty Research

The FeSe-based superconductors exhibit a wide range of critical temperature Tcunder a variety of material and physical conditions, but extensive studies to date have yet to produce a consensus view on the underlying mechanism. Here we report on a systematic Raman-scattering work on intercalated FeSe superconductors Lix(NH3)yFe2Se2 and (Li,Fe)OHFeSe compared to pristine FeSe. All three crystals show an anomalous power-law temperature dependence of phonon linewidths, deviating from the standard anharmonic behavior. This intriguing phenomenon is attributed to electron-phonon coupling effects enhanced by electron correlation, as evidenced by the evolution of the A1g Raman mode. Meanwhile, an analysis of the B1g …

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Training Underrepresented High School Students As A Strategy To Increase Diversity In The Biomedical Research And Health Professions Workforce, Dolores E. Caffey-Fleming, Ms, Mph, Lourdes Guerrero, Edd, Msw, Keith C. Norris, M.D., Phd Aug 2019

Training Underrepresented High School Students As A Strategy To Increase Diversity In The Biomedical Research And Health Professions Workforce, Dolores E. Caffey-Fleming, Ms, Mph, Lourdes Guerrero, Edd, Msw, Keith C. Norris, M.D., Phd

Journal of Health Disparities Research and Practice

This manuscript introduces the abstracts from the University of California, Los Angeles Coordinating Center.

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Need For Advancing Underrepresented Minorities In The Health Sciences And Medicine, Bonnie Halpern-Felsher, Phd, Sheila Mclaughlin, Mfa Aug 2019

Need For Advancing Underrepresented Minorities In The Health Sciences And Medicine, Bonnie Halpern-Felsher, Phd, Sheila Mclaughlin, Mfa

Journal of Health Disparities Research and Practice

This manuscript introduces the abstracts from the Stanford Coordinating Center.

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The Influence Of Legal Brothels On Illegal Sexual Service Purchasing Habits: The U.S. Context, Chris Wakefield, Barbara G. Brents Aug 2019

The Influence Of Legal Brothels On Illegal Sexual Service Purchasing Habits: The U.S. Context, Chris Wakefield, Barbara G. Brents

Sociology Faculty Research

In this study, we use a survey of sex workers’ clients to examine the relationship between having paid for services in legal brothels in Nevada and paying for criminalized sexual services among male clients. Using ordinary least squares (OLS) and generalized ordered logistic regression models, the use of legal brothels is found to be negatively related to reported purchasing of criminalized sexual services, regardless of criminal history, income, and most other demographic factors. When tested by criminalized purchase context, purchases made using the Internet, from public, outdoor contacts (such as the street) and indoor, public contacts (like bars), were less …

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