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An Effective And Efficient Analytic Technique: A Bootstrap Regression Procedure And Benford's Law, Ik Seon Suh, Todd C. Headrick Jul 2011

An Effective And Efficient Analytic Technique: A Bootstrap Regression Procedure And Benford's Law, Ik Seon Suh, Todd C. Headrick

Publications

Previous studies in auditing have proposed statistical analytic techniques to determine the presence of unusual fluctuations in financial data. However, these techniques use past financial data and/or other explanatory variables to compute expectation parameters. If past data were contaminated with errors or fraud, then the precision of developed expectations is questionable and this leads to an increase in Type II error. The current study introduces a new analytic technique known as the bootstrap regression (BREG) procedure in the context of Benford’s Law. The BREG procedure mitigates Type II error based on Benford parameters and exact confidence intervals to assess for …

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The 2009 Samoa And 2010 Chile Tsunamis As Observed In The Ionosphere Using Gps Total Electron Content, David A. Galvan, Attila Komjathy, Michael P. Hickey Ph.D., Anthony J. Mannucci Jun 2011

The 2009 Samoa And 2010 Chile Tsunamis As Observed In The Ionosphere Using Gps Total Electron Content, David A. Galvan, Attila Komjathy, Michael P. Hickey Ph.D., Anthony J. Mannucci

Publications

Ground‐based Global Positioning System (GPS) measurements of ionospheric total electron content (TEC) show variations consistent with atmospheric internal gravity waves caused by ocean tsunamis following two recent seismic events: the Samoa earthquake of 29 September 2009 and the Chile earthquake of 27 February 2010. Both earthquakes produced ocean tsunamis that were destructive to coastal communities near the epicenters, and both were observed in tidal gauge and buoy measurements throughout the Pacific Ocean. We observe fluctuations in TEC correlated in time, space, and wave properties with these tsunamis using the Jet Propulsion Laboratory’s Global Ionospheric Mapping software. These TEC measurements were …

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Group Velocity And Energy Flux In The Thermosphere: Limits On The Validity Of Group Velocity In A Viscous Atmosphere, R. L. Walterscheid, Michael P. Hickey Ph.D. Jun 2011

Group Velocity And Energy Flux In The Thermosphere: Limits On The Validity Of Group Velocity In A Viscous Atmosphere, R. L. Walterscheid, Michael P. Hickey Ph.D.

Publications

The response to wave forcing of finite duration comprises a transient forerunner and the steady state signal (or simply the signal). It is the latter that carries information on the spectral content of the forcing, and the signal velocity is the velocity at which wave energy flows. To the extent that group velocity is a good measure of the energy flow velocity, the ray‐tracing formalism is a valid description of signal propagation. We have examined vertical group velocities as a measure of vertical energy flow velocity for gravity and acoustic waves propagating into the dissipative lower thermosphere. We find that …

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On The Origin Of Fluctuations In The Cusp Diamagnetic Cavity, K. Nykyri, A. Otto, E. Adamson, A. Tjulin Jun 2011

On The Origin Of Fluctuations In The Cusp Diamagnetic Cavity, K. Nykyri, A. Otto, E. Adamson, A. Tjulin

Publications

We have analyzed Cluster magnetic field and plasma data during high‐altitude cusp crossing on 14 February 2003. Cluster encountered a diamagnetic cavity (DMC) during northward interplanetary magnetic field (IMF) conditions, and as IMF rotated southward, the spacecraft reencountered the cavity more at the sunward side. The DMC is characterized by a high level of magnetic field fluctuations and high‐energy electrons and protons. Ultralow‐frequency turbulence has been suggested as a mechanism to accelerate particles in DMC. We demonstrate in this paper for the first time that many of the low‐frequency fluctuations in the cavity are back and forth motion of the …

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Issues And Techniques In Translating Scientific Terms From English To Khmer For A University-Level Text In Cambodia, Cassie F. Quigley, Alandeom W. Oliviera, Alistair Curry, Gayle Buck Jun 2011

Issues And Techniques In Translating Scientific Terms From English To Khmer For A University-Level Text In Cambodia, Cassie F. Quigley, Alandeom W. Oliviera, Alistair Curry, Gayle Buck

Publications

Teachers and students spend much time interacting with written resources such as textbooks, tests, or worksheets during classroom instruction. What if no text is available, however, in the language of the learners? This case study describes the processes and techniques adopted by two university lecturers in Cambodia, as they translated an L1 (first language) science text into Khmer in a manner that tried to take full account of the cultural, linguistic, and social dimensions of language. Using a variety of translation techniques, they aimed to produce a Khmer text which would be most effective in promoting the learning of the …

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Isopods Failed To Acclimate Their Thermal Sensitivity Of Locomotor Performance During Predictable Or Stochastic Cooling, Michael W. Sears, Matthew S. Schuler, Brandon S. Cooper, Jonathan J. Storm, Michael J. Angilletta Jun 2011

Isopods Failed To Acclimate Their Thermal Sensitivity Of Locomotor Performance During Predictable Or Stochastic Cooling, Michael W. Sears, Matthew S. Schuler, Brandon S. Cooper, Jonathan J. Storm, Michael J. Angilletta

Publications

Most organisms experience environments that vary continuously over time, yet researchers generally study phenotypic responses to abrupt and sustained changes in environmental conditions. Gradual environmental changes, whether predictable or stochastic, might affect organisms differently than do abrupt changes. To explore this possibility, we exposed terrestrial isopods (Porcellio scaber) collected from a highly seasonal environment to four thermal treatments: (1) a constant 20°C; (2) a constant 10°C; (3) a steady decline from 20° to 10°C; and (4) a stochastic decline from 20° to 10°C that mimicked natural conditions during autumn. After 45 days, we measured thermal sensitivities of running …

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On The Role Of Electrostatics In Protein–Protein Interactions, Zhe Zhang, Shawn Witham, Emil Alexov Jun 2011

On The Role Of Electrostatics In Protein–Protein Interactions, Zhe Zhang, Shawn Witham, Emil Alexov

Publications

The role of electrostatics in protein–protein interactions and binding is reviewed in this paper. A brief outline of the computational modeling, in the framework of continuum electrostatics, is presented and the basic electrostatic effects occurring upon the formation of the complex are discussed. The effect of the salt concentration and pH of the water phase on protein–protein binding free energy is demonstrated which indicates that the increase of the salt concentration tends to weaken the binding, an observation that is attributed to the optimization of the charge–charge interactions across the interface. It is pointed out that the pH-optimum (pH of …

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Ro-Vibrational Co Detected In The Β Pictoris Circumstellar Disk, Matthew R. Troutman, Kenneth H. Hinkle, Joan R. Najita, Terrence W. Rettig, Sean D. Brittain Jun 2011

Ro-Vibrational Co Detected In The Β Pictoris Circumstellar Disk, Matthew R. Troutman, Kenneth H. Hinkle, Joan R. Najita, Terrence W. Rettig, Sean D. Brittain

Publications

We present high-resolution near-infrared spectra of β Pictoris—a nearby young star with a debris disk. Fundamental low-J CO absorption lines are detected and strict upper limits are placed on the flux of v = 2–1 low-J CO emission lines. The limit on the UV fluorescent emission flux in the v = 2–1 lines is used to place a tight constraint on the inner extent of the CO gas. Assuming Hi is the primary collision partner, the sub-thermal population of the low-J v = 0 rotational levels constrains the density of the gas in the disk to nH = (2.5+7.1 −1.2)×105 …

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New Species Of Marsupial Frog (Hemiphractidae: Gastrotheca) From An Isolated Montane Forest In Southern Peru, Alessandro Catenazzi, Rudolf Von May Jun 2011

New Species Of Marsupial Frog (Hemiphractidae: Gastrotheca) From An Isolated Montane Forest In Southern Peru, Alessandro Catenazzi, Rudolf Von May

Publications

We describe a new species of marsupial frog (genus Gastrotheca) from an isolated patch of cloud forest in the upper reaches of the Pachachaca River, a tributary of the Apurimac River in southern Peru (Apurimac Region). The new species is small with males less than 30 mm and a single female 35.3 mm in snout–vent length. A juvenile was collected from inside an epiphytic bromeliad at ~3 m, suggesting that this species is arboreal or uses bromeliad tanks as microhabitats. We describe the advertisement call, which has a dominant frequency above 2.2 kHz. Based on morphology and advertisement call, …

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Writing Development Over Time: Examining Preservice Teachers’ Attitudes And Beliefs About Writing, Anna H. Hall, Jennifer Grisham-Brown May 2011

Writing Development Over Time: Examining Preservice Teachers’ Attitudes And Beliefs About Writing, Anna H. Hall, Jennifer Grisham-Brown

Publications

Since writing ability has been found to be a key indicator of school success and successful participation in the workplace, it is important for preservice teachers to receive effective preparation in the area of writing. Reflecting on personal writing experiences allows preservice teachers to examine their own attitudes and beliefs about writing and the effects their attitudes and beliefs may have on their pedagogical decisions in the future. This article describes the findings from two focus groups conducted with preschool and elementary preservice teachers during which participants examined their attitudes towards writing that have developed over time and their plans …

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Abundances Of Stars With Planets: Trends With Condensation Temperature, Simon C. Schuler, Davin Flateau, Katia Cunha, Jeremy R. King, Luan Ghezzi, Verne V. Smith May 2011

Abundances Of Stars With Planets: Trends With Condensation Temperature, Simon C. Schuler, Davin Flateau, Katia Cunha, Jeremy R. King, Luan Ghezzi, Verne V. Smith

Publications

Precise abundances of 18 elements have been derived for 10 stars known to host giant planets from high signal-to-noise ratio, high-resolution echelle spectroscopy. Internal uncertainties in the derived abundances are typically 0.05 dex. The stars in our sample have all been previously shown to have abundances that correlate with the condensation temperature (Tc) of the elements in the sense of increasing abundances with increasing Tc; these trends have been interpreted as evidence that the stars may have accreted H-depleted planetary material. Our newly derived abundances also correlate positively with Tc, although slopes of linear least-square fits to the [m/H]–Tc relations …

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Construction Of Papaya Male And Female Bac Libraries And Application In Physical Mapping Of The Sex Chromosomes, Andrea R. Gschwend, Qingyi Yu, Paul Moore, Christopher Saski, Cuixia Chen, Jianping Wang, Jong-Kuk Na, Ray Ming May 2011

Construction Of Papaya Male And Female Bac Libraries And Application In Physical Mapping Of The Sex Chromosomes, Andrea R. Gschwend, Qingyi Yu, Paul Moore, Christopher Saski, Cuixia Chen, Jianping Wang, Jong-Kuk Na, Ray Ming

Publications

Papaya is a major fruit crop in the tropics and has recently evolved sex chromosomes. Towards sequencing the papaya sex chromosomes, two bacterial artificial chromosome (BAC) libraries were constructed from papaya male and female genomic DNA. The female BAC library was constructed using restriction enzyme BstY I and consists of 36,864 clones with an average insert size of 104 kb, providing 10.3x genome equivalents. The male BAC library was constructed using restriction enzyme EcoR I and consists of 55,296 clones with an average insert size of 101 kb, providing 15.0x genome equivalents. The male BAC library was used in constructing …

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Identification Of A Phytase Gene In Barley (Hordeum Vulgare L.), Fei Dai, Long Qiu, Lingzhen Ye, Dezhi Wu, Meixue Zhou, Guoping Zhang Apr 2011

Identification Of A Phytase Gene In Barley (Hordeum Vulgare L.), Fei Dai, Long Qiu, Lingzhen Ye, Dezhi Wu, Meixue Zhou, Guoping Zhang

Publications

BACKGROUND: Endogenous phytase plays a crucial role in phytate degradation and is thus closely related to nutrient efficiency in barley products. The understanding of genetic information of phytase in barley can provide a useful tool for breeding new barley varieties with high phytase activity. METHODOLOGY/PRINCIPAL FINDINGS: Quantitative trait loci (QTL) analysis for phytase activity was conducted using a doubled haploid population. Phytase protein was purified and identified by the LC-ESI MS/MS Shotgun method. Purple acid phosphatase (PAP) gene was sequenced and the position was compared with the QTL controlling phytase activity. A major QTL for phytase activity was mapped to …

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Detection Of Ch+ Emission From The Disc Around Hd 100546, W F. Thi, F Menard, G Meeus, C. Martin-Zaidi, P Woitke, E Tatulli, M Benisty, I Kamp, I Pascucci, C Pinte, C A. Grady, Sean D. Brittain, G J. White, C D. Howard, G Sandell, C Eiroa Apr 2011

Detection Of Ch+ Emission From The Disc Around Hd 100546, W F. Thi, F Menard, G Meeus, C. Martin-Zaidi, P Woitke, E Tatulli, M Benisty, I Kamp, I Pascucci, C Pinte, C A. Grady, Sean D. Brittain, G J. White, C D. Howard, G Sandell, C Eiroa

Publications

Despite its importance in the thermal balance of the gas and in the determination of primeval planetary atmospheres, the chemistry in protoplanetary discs remains poorly constrained with only a handful of detected species. We observed the emission from the disc around the Herbig Be star HD 100546 with the PACS instrument in the spectroscopic mode on board the Herschel Space Telescope as part of the GAS in Protoplanetary Systems (GASPS) programme and used archival data from the DIGIT programme to search for the rotational emission of CH+. We detected in both datasets an emission line centred at 72.16 μm that …

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Uaa Student Showcase Journal: Recognizing Excellence (2011), N/A N/A Apr 2011

Uaa Student Showcase Journal: Recognizing Excellence (2011), N/A N/A

Publications

No abstract provided.

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Defining And Addressing Expectations For L2 Writers Across Disciplines, Lindsey Ives, Tom Pierce, Michael Schwartz Apr 2011

Defining And Addressing Expectations For L2 Writers Across Disciplines, Lindsey Ives, Tom Pierce, Michael Schwartz

Publications

A presentation divided into three sections: Student Perspectives given by Michael Schwartz, Teacher Perspectives given by Lindsey Ives, and Administrator Perspectives given by Tom Pierce.

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A Dreary Life On A Barge: From L'Atalante To Young Adam, Walter C. Metz Apr 2011

A Dreary Life On A Barge: From L'Atalante To Young Adam, Walter C. Metz

Publications

This paper compares the French Poetic Realist masterpiece, L'Atalante (Jean Vigo, 1934) with the contemporary Scottish film, Young Adam (David Mackenzie, 2003), adapted from the 1954 Beat novel by Alexander Trocchi.

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Effect Of Partial Substitution Of Ni By Co On The Magnetic And Magnetocaloric Properties Of Ni50Mn35In15 Heusler Alloy, Arjun K. Pathak, Igor Dubenko, Yimin Xiong, Philip W. Adams, Shane Stadler, Naushad Ali Apr 2011

Effect Of Partial Substitution Of Ni By Co On The Magnetic And Magnetocaloric Properties Of Ni50Mn35In15 Heusler Alloy, Arjun K. Pathak, Igor Dubenko, Yimin Xiong, Philip W. Adams, Shane Stadler, Naushad Ali

Publications

The magnetic and magnetocaloric properties of Ni48Co2Mn35In15 were studied using magnetization and heat capacity measurements. The magnetic entropy change (Delta SM) was evaluated from both magnetizing and demagnetizing fields. An inverse Delta SM for the magnetizing and demagnetizing processes were found to be 20.5 and 18.5 J kg-1 K-1, respectively, for Delta H = 5 T at the martensitic transition (T=TM). The normal Delta SM was found to be -5.4 J kg-1 K-1 for both fields at the paramagnetic/ferromagnetic transition (T=TC …

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Examining Youth Camping Outcomes Across Multiple States: The National 4-H Camping Research Consortium (Ncrc), Barry A. Garst, Allison Nichols, Jill Martz, Niki Nestor Mcneely, Laura Bovitz, Denise Frebertshauser, Suzanne Le Menestrel, Jill Walahoski Apr 2011

Examining Youth Camping Outcomes Across Multiple States: The National 4-H Camping Research Consortium (Ncrc), Barry A. Garst, Allison Nichols, Jill Martz, Niki Nestor Mcneely, Laura Bovitz, Denise Frebertshauser, Suzanne Le Menestrel, Jill Walahoski

Publications

The impact of residential camp participation is needed for camps focused on a variety of outcomes including education, summer fun, prevention, and youth development. One system, the Cooperative Extension Service, conducts 4-H residential camps in most states nationwide every year. These camps, though offering educational enhancement and fun activities, are focused on youth development, incorporating a framework called the essential elements of positive youth development. The National 4-H Camping Research Consortium (NCRC), a group of Extension specialists and county-level educators, designed and piloted assessment tools for 4-H camps that can be used at any camp that focuses on youth development. …

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The Relationship Between Student Identity Development And The Perception Of Political Bias In The College Classroom, Darren Linvill Apr 2011

The Relationship Between Student Identity Development And The Perception Of Political Bias In The College Classroom, Darren Linvill

Publications

This study explored the relationship between identity development, as gauged by Marcia's identity development construct, and student perception of instructor political bias. Regression analysis was employed to compare participant responses on the Ego Identity Process Questionnaire, a measure of Marcia's construct, with the Political Bias in the Classroom Survey, a measure gauging perceptions of and reactions to instructor political bias. The EIPQ's commitment scale was found to be a significant positive indicator for the PBCS's perception scale, suggesting that students who are strongly committed to their identity are more likely to perceive an instructor as having a political bias. Recommendations …

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Is Sexual Monomorphism A Predictor Of Polygynandry? Evidence From A Social Mammal, The Collared Peccary, Jennifer Daniel Cooper, Peter M. Waser, Eric C. Hellgren, Timothy M. Gabor, J. A. Dewoody Apr 2011

Is Sexual Monomorphism A Predictor Of Polygynandry? Evidence From A Social Mammal, The Collared Peccary, Jennifer Daniel Cooper, Peter M. Waser, Eric C. Hellgren, Timothy M. Gabor, J. A. Dewoody

Publications

Sexual dimorphism is common in polygynous species, and there is clear evidence that both intra-sexual competition and female preferences can drive the evolution of large body size in males. In contrast, sexual monomorphism is often argued to reflect a relaxation of male mate competition or an intensification of resource competition among females. Alternatively, it might imply opportunities for females to circumvent or counteract male mate competition in a polygynandrous mating system. We test the prediction that sexual monorphism is associated with polygynandry in the collared peccary (Pecari tajacu, Tayassuidae), a social ungulate closely related to the old-world suids. …

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Magnetic And Magnetocaloric Properties Of Gd6X2Si3 (X = Ni, Co) And Ln6Co2Si3 (Ln = Pr, La), Arjun K. Pathak, Igor Dubenko, Shane Stadler, Naushad Ali Apr 2011

Magnetic And Magnetocaloric Properties Of Gd6X2Si3 (X = Ni, Co) And Ln6Co2Si3 (Ln = Pr, La), Arjun K. Pathak, Igor Dubenko, Shane Stadler, Naushad Ali

Publications

Phase compositions and crystal structures of Gd6X2Si3 (X = Ni, Co) and Ln6Co2Si3 (Ln = Pr, La) have been studied. The magnetic properties of Gd6X2Si3 (X = Ni, Co) and Ln6Co2Si3 (Ln = Pr, La) have been evaluated from magnetization measurements performed by a superconducting quantum interference device magnetometer in a temperature interval of 5–400 K, and at magnetic fields up to 5 T. The crystal structures of Gd6X2Si3 (X = Co, Ni) and Ln …

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A Method For Providing High-Volume Interprofessional Simulation Encounters In Physical And Occupational Therapy Education Programs, Michael J. Shoemaker Pt, Dpt, Jeanine Beasley Edd, Otr, Megan Cooper Bs, Ron Perkins Bsn, Rn, Jeanne Smith Bs, Ba, Chris Swank Ma Apr 2011

A Method For Providing High-Volume Interprofessional Simulation Encounters In Physical And Occupational Therapy Education Programs, Michael J. Shoemaker Pt, Dpt, Jeanine Beasley Edd, Otr, Megan Cooper Bs, Ron Perkins Bsn, Rn, Jeanne Smith Bs, Ba, Chris Swank Ma

Publications

With an increasing emphasis on interprofessional education within the allied health professions, simulation has potential for being a useful teaching modality for providing collaborative learning experiences for occupational and physical therapist students. However, there are many challenges associated with conducting simulations with large numbers of students. We describe the design, planning, cost, and support staff time required for conducting an interprofessional simulation of the intensive care setting, including a methodology for maximizing resources and student opportunities for participation for 64 physical and occupational therapy students over a 4-hour time period. Qualitative analyses of student experiences are also presented.

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The Mechanics Of The Tectonic Man: Comedy And The Ludic Function Of A Serious Man And Punch-Drunk Love, Walter C. Metz Apr 2011

The Mechanics Of The Tectonic Man: Comedy And The Ludic Function Of A Serious Man And Punch-Drunk Love, Walter C. Metz

Publications

The paper uses the cultural historical methods of Johan Huizinga, particularly on the comedic, ludic nature of social life to read two films: Paul Thomas Anderson's Punch-Drunk Love and the Coen Brothers' A Serious Man.

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In Search Of A Third Culture: Towards An Experimental Science And Nature Cinema, Walter C. Metz Apr 2011

In Search Of A Third Culture: Towards An Experimental Science And Nature Cinema, Walter C. Metz

Publications

This essay attempts to move beyond C.P. Snow’s reductive formulation of the two cultures, positing a third culture forged out of the collision of science documentary television with the avant-garde traditions of the cinema. In particular, I use both scientific and humanistic understandings of memory to compare and contrast a science television program, “Understanding the Mysteries of Memory” (Science Channel, 2002) with an avant-garde film, Report (Bruce Conner, 1967).

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Addressing Water Quality Issues In Rural Cameroon With Household Biosand Filters, Laine Klopfensten, Laura Petrasky, Valerie Winton, Jeff Brown Apr 2011

Addressing Water Quality Issues In Rural Cameroon With Household Biosand Filters, Laine Klopfensten, Laura Petrasky, Valerie Winton, Jeff Brown

Publications

This paper describes an ongoing collaboration between the Hope College student chapter of Engineers Without Borders – USA and the rural community of Nkuv in the Northwest Province of Cameroon related to improving drinking water quality using Manz biosand filters. The collaboration began in 2006 and focused on developing a community-based construction and distribution model for household water treatment units. Results from microbiology testing of the constructed filters indicate that this water treatment method is effective for improving water quality in rural areas. The results also highlight the need for ongoing assessment and adapting community education programs to provide necessary …

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Cluster Observations Of A Cusp Diamagnetic Cavity: Structure, Size, And Dynamics, K. Nykyri, A. Otto, E. Adamson, E. Dougal, J. Mumme Mar 2011

Cluster Observations Of A Cusp Diamagnetic Cavity: Structure, Size, And Dynamics, K. Nykyri, A. Otto, E. Adamson, E. Dougal, J. Mumme

Publications

We have analyzed Cluster magnetic field and plasma data during high‐altitude cusp crossing and compared them with high‐resolution MHD simulations. Cluster encountered a diamagnetic cavity (DMC) during northward interplanetary magnetic field (IMF) conditions, and as the IMF rotated southward, the spacecraft reencountered the cavity more at the sunward side of the cusp because the reconnection site had changed location. We found evidence of magnetic reconnection both during northward and southward IMF conditions. The Cluster separation was ∼5000 km, enabling for the first time measurements both inside the DMC and surrounding boundaries that allowed us to construct the structure of the …

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Water Depletion In The Disk Atmosphere Of Herbig Aebe Stars, D Fedele, I Pascucci, Sean D. Brittain, I Kamp, P Woitke, J P. Williams, W.R.F. Dent, W F. Thi Mar 2011

Water Depletion In The Disk Atmosphere Of Herbig Aebe Stars, D Fedele, I Pascucci, Sean D. Brittain, I Kamp, P Woitke, J P. Williams, W.R.F. Dent, W F. Thi

Publications

We present high-resolution (R ∼ 100,000) L-band spectroscopy of 11 Herbig AeBe stars with circumstellar disks. The observations were obtained with the VLT/CRIRES to detect hot water and hydroxyl radical emission linespreviously detected in disks around T Tauri stars. OH emission lines are detected toward four disks. The OH 2Π3/2 P4.5 (1+,1−) doublet is spectrally resolved as well as the velocity profile of each component of the doublet. Its characteristic double-peak profile demonstrates that the gas is in Keplerian rotation and points to an emitting region extending out to ∼15–30 AU. The OH emission correlates with disk geometry as it …

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The Unusual Protoplanetary Disk Around The T Tauri Star Et Chamaeleontis, P Woitke, B Riaz, G Duchene, I Pascucci, A Ran Lyo, W.R.F. Dent, N Phillips, W F. Thi, F Menard, G J. Herczeg, E Bergin, A Brown, A Mora, I Kamp, G Aresu, Sean D. Brittain, I De Gregorio-Monsalvo, G Sandell Mar 2011

The Unusual Protoplanetary Disk Around The T Tauri Star Et Chamaeleontis, P Woitke, B Riaz, G Duchene, I Pascucci, A Ran Lyo, W.R.F. Dent, N Phillips, W F. Thi, F Menard, G J. Herczeg, E Bergin, A Brown, A Mora, I Kamp, G Aresu, Sean D. Brittain, I De Gregorio-Monsalvo, G Sandell

Publications

We present new continuum and line observations, along with modelling, of the faint (6−8) Myr old T Tauri star ETCha belonging to the η Chamaeleontis cluster. We have acquired Herschel/PACS photometric fluxes at 70 μm and 160 μm, as well as a detection of the [OI] 63 μm fine-structure line in emission, and derived upper limits for some other far-IR OI, CII, CO and o-H2O lines. These observations were carried out in the frame of the open time key programme GASPS, where ETCha was selected as one of the science demonstration phase targets. The Herschel data is complemented by new …

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The White Dwarf Age Of Nfc 2477, Elizabeth J. Jeffery, Ted Von Hippel, Et Al. Mar 2011

The White Dwarf Age Of Nfc 2477, Elizabeth J. Jeffery, Ted Von Hippel, Et Al.

Publications

We present deep photometric observations of the open cluster NGC 2477 using HST/WFPC2. By identifying seven cluster white dwarf candidates, we present an analysis of the white dwarf age of this cluster, using both the traditional method of fitting isochrones to the white dwarf cooling sequence, and by employing a new Bayesian statistical technique that has been developed by our group. This new method performs an objective, simultaneous model fit of the cluster and stellar parameters (namely, age, metallicity, distance, reddening, as well as individual stellar masses, mass ratios, and cluster membership) to the photometry. Based on this analysis, …

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