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Real-Time System Identification For Impact-Based Part Positioning, Laine Mears, Jeannie Falcon Mar 2007

Real-Time System Identification For Impact-Based Part Positioning, Laine Mears, Jeannie Falcon

Publications

Simplified part positioning in manufacturing has been achieved using pushing or tapping actuation in place of more complex pick-and-place systems. However, positioning by impact introduces a new source of uncertainty: interfacial frictional effects of sliding, which can result in an uncontrollable and often poorlypredictable actuation distance. The described work provides a friction-based dynamic model of the sliding distance after impact that is used to predict static friction characteristics. A prototype system is simulated and validation data used to improve the model. A control algorithm is also described, tested and validated over a range of actuated masses.

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Inverse Magnetocaloric Effect In Ferromagnetic Ni50mn37+Xsb13−X Heusler Alloys, Mahmud Khan, Naushad Ali, Shane Stadler Mar 2007

Inverse Magnetocaloric Effect In Ferromagnetic Ni50mn37+Xsb13−X Heusler Alloys, Mahmud Khan, Naushad Ali, Shane Stadler

Publications

A study of the magnetocaloric effect (MCE) in the ferromagnetic Heusler alloys Ni50Mn37+xSb13−x (x = 0,0.5,1) has been carried out through magnetization measurements. An inverse magnetocaloric effect was observed in the vicinity of the first order martensitic transition. A maximum positive magnetic entropy change of ΔSm ≈ 19 J/kg K at approximately 297 K for a magnetic field change of 5 T was observed. It is demonstrated that the martensitic transformation temperature, and the corresponding ΔSm, can be tuned through a slight variation in composition.

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The Metallicity Distribution Of Intracluster Stars In Virgo, Benjamin F. Willaims, Ted Von Hippel, Et Al. Feb 2007

The Metallicity Distribution Of Intracluster Stars In Virgo, Benjamin F. Willaims, Ted Von Hippel, Et Al.

Publications

We have used the Hubble Space Telescope's Advanced Camera for Surveys (ACS) to detect and measure ~5300 stars in a single intracluster field in the Virgo Cluster. By performing F606W and F814W photometry on these stars, we have determined their metallicity distribution function and constrained the types of stars present in this portion of Virgo's intracluster space. Based on the small number of stars detected that were brighter than the red giant branch (RGB) tip, we suggest that in this region, Virgo's intracluster stars are mostly old (10 Gyr). Through analysis of the RGB stars themselves, we determine that …

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The Resolved Stellar Populations Of A Dwarf Spheroidal Galaxy In The Virgo Cluster, Patrick R. Durell, Ted Von Hippel, Et Al. Feb 2007

The Resolved Stellar Populations Of A Dwarf Spheroidal Galaxy In The Virgo Cluster, Patrick R. Durell, Ted Von Hippel, Et Al.

Publications

We report on the discovery of a faint (MV ~ -10.6 ± 0.2) dwarf spheroidal galaxy on deep F606W and F814W Hubble Space Telescope images of a Virgo intracluster field. The galaxy is easily resolved in our images, as our color magnitude diagram (CMD) extends 1 magnitude beyond the tip of the red giant branch (RGB). Thus, it is the deepest CMD for a small dwarf galaxy inside a cluster environment. Using the colors of the RGB stars, we derive a metal abundance for the dwarf of [M/H] = -2.3 ± 0.3 and show that the metallicity dispersion …

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Urban Physiology: City Ants Possess High Heat Tolerance, Michael W. Sears, Michael J. Angilletta, Robbie S. Wilson, Amanda C. Niehaus, Pedro L. Ribeiro, Carlos A. Navas Feb 2007

Urban Physiology: City Ants Possess High Heat Tolerance, Michael W. Sears, Michael J. Angilletta, Robbie S. Wilson, Amanda C. Niehaus, Pedro L. Ribeiro, Carlos A. Navas

Publications

Urbanization has caused regional increases in temperature that exceed those measured on a global scale, leading to urban heat islands as much as 12°C hotter than their surroundings. Optimality models predict ectotherms in urban areas should tolerate heat better and cold worse than ectotherms in rural areas. We tested these predications by measuring heat and cold tolerances of leaf-cutter ants from South America’s largest city (São Paulo, Brazil). Specifically, we compared thermal tolerances of ants from inside and outside of the city. Knock-down resistance and chill-coma recovery were used as indicators of heat and cold tolerances, respectively. Ants from within …

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Design Of A Flexible Centering Tooling System, Laine Mears, Francis M. Kolartis, Michael Thompson, Thomas R. Kurfess Feb 2007

Design Of A Flexible Centering Tooling System, Laine Mears, Francis M. Kolartis, Michael Thompson, Thomas R. Kurfess

Publications

Precise machining of bearing rings is integral to finished bearing assembly quality. The output accuracy of centre-based machining systems relates directly to the precision of part centring before machining. Traditional tooling is subject to wear, dimensional inaccuracy and human error. A flexible tooling system for initial part centring is proposed based on a single measurement system and actuator. In this system, the part is rotated and measured to identify centre of geometry offset from centre of rotation, then moved by a series of pushes to align the centres. The actuation algorithm is self-modifying based on residual error. This tooling control …

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Effects Of Joint Space Use And Group Membership On Contact Rates Among White-Tailed Deer, Eric M. Schauber, Daniel J. Storm, Clayton K. Nielsen Feb 2007

Effects Of Joint Space Use And Group Membership On Contact Rates Among White-Tailed Deer, Eric M. Schauber, Daniel J. Storm, Clayton K. Nielsen

Publications

Establishment and spread of infectious diseases are controlled by the frequency of contacts among hosts. Although managers can estimate transmission coefficients from the relationship between disease prevalence and age or time, they may wish to quantify or compare contact rates before a disease is established or while it is at very low prevalence. Our objectives were to quantify direct and indirect contacts rates among white-tailed deer (Odocoileus virginianus) and to compare these measures of contact rate with simpler measures of joint space use. We deployed Global Positioning System (GPS) collars on 23 deer near Carbondale, Illinois, USA, from …

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Time-Resolved Ducting Of Atmospheric Acoustic-Gravity Waves By Analysis Of The Vertical Energy Flux, Yonghui Yu, Michael P. Hickey Ph.D. Jan 2007

Time-Resolved Ducting Of Atmospheric Acoustic-Gravity Waves By Analysis Of The Vertical Energy Flux, Yonghui Yu, Michael P. Hickey Ph.D.

Publications

A new 2-D time-dependent model is used to simulate the propagation of an acoustic-gravity wave packet in the atmosphere. A Gaussian tropospheric heat source is assumed with a forcing period of 6.276 minutes. The atmospheric thermal structure creates three discrete wave ducts in the stratosphere, mesosphere, and lower thermosphere, respectively. The horizontally averaged vertical energy flux is derived over altitude and time in order to examine the time-resolved ducting. This ducting is characterized by alternating upward and downward energy fluxes within a particular duct, which clearly show the reflections occurring from the duct boundaries. These ducting simulations are the first …

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Soldier/Hardware-In-The-Loop Simulation-Based Combat Vehicle Duty Cycle Measurement: Duty Cycle Experiment 2, Mark Brudnak, Mike Pozolo, Victor Paul, Syed Mohammad, Marc Compere, Et Al. Jan 2007

Soldier/Hardware-In-The-Loop Simulation-Based Combat Vehicle Duty Cycle Measurement: Duty Cycle Experiment 2, Mark Brudnak, Mike Pozolo, Victor Paul, Syed Mohammad, Marc Compere, Et Al.

Publications

This paper describes a human-in-the-loop motion-based simulator interfaced to hybrid-electric power system hardware both of which were used to measure the duty cycle of a combat vehicle in a virtual simulation environment. The project discussed is a greatly expanded follow-on to the experiment published in [1]. This paper is written in the context of [1] and therefore highlights the enhancements. The most prominent of these enhancements is the integration (in real-time) of the Power & Electric System Integration Lab (P&E SIL) with a motion base simulator by means of a “long haul” connection over the Internet (a geographical distance of …

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A Dyad Theory Of Hydrodynamics And Electrodynamics, Preston Jones Jan 2007

A Dyad Theory Of Hydrodynamics And Electrodynamics, Preston Jones

Publications

The dyadic calculus is developed in a form suitable for the description of physical relations in curved space. The 4-space equations of hydrodynamics and electrodynamics are constructed using this dyadic calculus. As a demonstration of the relationship between gravity and electrodynamics a time varying metric is shown to generate electromagnetic radiation.

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Chemical And Dynamical Processes In The Mesospheric Emissive Layer. First Results Of Stereoscopic Observations, M. Faivre, G. Moreels, Pierre-Dominique Pautet, J. Clairemidi, F. Dumont, O. Lorin, F. Colas Jan 2007

Chemical And Dynamical Processes In The Mesospheric Emissive Layer. First Results Of Stereoscopic Observations, M. Faivre, G. Moreels, Pierre-Dominique Pautet, J. Clairemidi, F. Dumont, O. Lorin, F. Colas

Publications

[1] The mesospheric emissive layer is an efficient tracer of the dynamical processes propagating in the atmosphere at that level. CCD images in the near infrared taken from the ground at slant angles often reveal the existence of wavy fields. A series of such images has been transformed, using matrix operations, producing a downward satellite-type view that covers a circular area of radius ∼1000 km at the altitude of the layer. The Fourier characteristics of the wave system are measured using a Morlet-type wavelet generator function with horizontal wavelengths of mostly ∼20–40 km and 100–150 km and temporal periods of …

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Virgo’S Intracluster Globular Clusters As Seen By The Advanced Camera For Surveys, Benjamin F. Williams, Robin Ciardullo, Ted Von Hippel, Et Al. Jan 2007

Virgo’S Intracluster Globular Clusters As Seen By The Advanced Camera For Surveys, Benjamin F. Williams, Robin Ciardullo, Ted Von Hippel, Et Al.

Publications

We report the discovery of four candidate intracluster globular clusters (IGCs) in a single deepHST ACS field of the Virgo Cluster. We show that each cluster is roughly spherical, has a magnitude near the peak of the Virgo globular cluster luminosity function, has a radial profile that is best fitted by a King model, and is surrounded by an excess of point sources that have the colors and magnitudes of cluster red giant stars. Despite the fact that two of our IGC candidates have integrated colors redder than the mean of the M87 globular cluster system, we propose that …

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Behavioral Indicators Of Predator Space Use: Studying Species Interactions Through The Behavior Of Predators, Kenneth A. Schmidt, Eric M. Schauber Jan 2007

Behavioral Indicators Of Predator Space Use: Studying Species Interactions Through The Behavior Of Predators, Kenneth A. Schmidt, Eric M. Schauber

Publications

Predation has major impacts on survival and reproductive success for many species. To quantify these effects, ecologists often choose to intensively study prey populations to measure predation rates and/or estimate predator abundance. But in some cases, predation rates are less strongly related to predator abundance per se than to spatial and temporal patterns of predator space use; thus, quantifying the latter may provide meaningful surrogates of predation rates that scale up to larger areas. This is particularly true when safety for prey, especially sessile and vulnerable prey, is strongly linked to predator-free space. Our own research programs have used two …

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Dendritic Cell-Expanded, Islet-Specific Cd4+ Cd25+ Cd62l+ Regulatory T Cells Restore Normoglycemia In Diabetic Nod Mice, Kristin V. Tarbell, Lucine Petit Francis, Xiaopan Zuo Jan 2007

Dendritic Cell-Expanded, Islet-Specific Cd4+ Cd25+ Cd62l+ Regulatory T Cells Restore Normoglycemia In Diabetic Nod Mice, Kristin V. Tarbell, Lucine Petit Francis, Xiaopan Zuo

Publications

Most treatments that prevent autoimmune diabetes in nonobese diabetic (NOD) mice require intervention at early pathogenic stages, when insulitis is first developing. We tested whether dendritic cell (DC)-expanded, islet antigen-specific CD4+ CD25+ suppressor T cells could treat diabetes at later stages of disease, when most of the insulin-producing islet β cells had been destroyed by infiltrating lymphocytes. CD4+ CD25+ CD62L+ regulatory T cells (T reg cells) from BDC2.5 T cell receptor transgenic mice were expanded with antigen-pulsed DCs and IL-2, and were then injected into NOD mice. A single dose of as few as 5 …

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Correction, Madhav V. Dhodapkar, Devi K. Banerjee, John E. Connolly Jan 2007

Correction, Madhav V. Dhodapkar, Devi K. Banerjee, John E. Connolly

Publications

[No abstract available]

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A Subset Of Dendritic Cells Induces Cd4+ T Cells To Produce Ifn-Γ By An Il-12-Independent But Cd70-Dependent Mechanism In Vivo, Helena Soares, Haena Waechter, Nicolas Glaichenhaus Jan 2007

A Subset Of Dendritic Cells Induces Cd4+ T Cells To Produce Ifn-Γ By An Il-12-Independent But Cd70-Dependent Mechanism In Vivo, Helena Soares, Haena Waechter, Nicolas Glaichenhaus

Publications

Interferon (IFN)-γ, a cytokine critical for resistance to infection and tumors, is produced by CD4+ helper T lymphocytes after stimulation by cultured dendritic cells (DCs) that secrete a cofactor, interleukin (IL)-12. We have identified a major IL-12-independent pathway whereby DCs induce IFN-γ-secreting T helper (Th)1 CD4+ T cells in vivo. This pathway requires the membrane-associated tumor necrosis family member CD70 and was identified by targeting the LACK antigen from Leishmania major within an antibody to CD205 (DEC-205), an uptake receptor on a subset of DCs. Another major DC subset, targeted with 33D1 anti-DCIR2 antibody, also induced IFN-γ in …

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Erratum: Sustained Expansion Of Nkt Cells And Antigen-Specific T Cells After Injection Of Α-Galactosyl-Ceramide Loaded Mature Dendritic Cells In Cancer Patients, David H. Chang, Keren Osman, John E. Connolly Jan 2007

Erratum: Sustained Expansion Of Nkt Cells And Antigen-Specific T Cells After Injection Of Α-Galactosyl-Ceramide Loaded Mature Dendritic Cells In Cancer Patients, David H. Chang, Keren Osman, John E. Connolly

Publications

[No abstract available]

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Atraumatic Oral Spray Immunization With Replication-Deficient Viral Vector Vaccines, Christiane P. Stahl-Hennig, Seraphin Kuate, Monika Franz Jan 2007

Atraumatic Oral Spray Immunization With Replication-Deficient Viral Vector Vaccines, Christiane P. Stahl-Hennig, Seraphin Kuate, Monika Franz

Publications

The development of needle-free vaccines is one of the recently defined "grand challenges in global health" (H. Varmus, R. Klausner, R. Klausner, R. Zerhouni, T. Acharya, A. S. Daar, and P. A. Singer, Science 302:398-399, 2003). To explore whether a natural pathway to the inductive site of the mucosa-associated lymphatic tissue could be exploited for atraumatic immunization purposes, replication-deficient viral vector vaccines were sprayed directly onto the tonsils of rhesus macaques. Tonsillar immunization with viral vector vaccines encoding simian immunodeficiency virus (SIV) antigens induced cellular and humoral immune responses. Viral RNA levels after a stringent SIV challenge were reduced, providing …

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Differences In Rust In Hearing Aid Batteries Across Four Manufacturers, Four Battery Sizes, And Five Durations Of Exposure, Michael Valente, Jamie H. Cadieux, Laura Flowers, John G. Newman, Juergen Scherer, Gerg Gephart Jan 2007

Differences In Rust In Hearing Aid Batteries Across Four Manufacturers, Four Battery Sizes, And Five Durations Of Exposure, Michael Valente, Jamie H. Cadieux, Laura Flowers, John G. Newman, Juergen Scherer, Gerg Gephart

Publications

No abstract provided.

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Should There Be A National Curriculum For Technological Literacy?, Laura J. Hummell, Ethan B. Lipton, Melissa Morrow, Jerry Streichler, Karen Zuga Jan 2007

Should There Be A National Curriculum For Technological Literacy?, Laura J. Hummell, Ethan B. Lipton, Melissa Morrow, Jerry Streichler, Karen Zuga

Publications

The author discusses her belief that the United States should have a national curriculum for technological literacy. The author asserts that there are huge discrepancies and deficiencies existing in technology-based curricula, and as a result students in the United States are being ill-prepared for living and working in a globally based economy and society. The author believes that if a national curriculum for technological literacy is developed it should resemble the Standards for Technological Literacy (2000/2002), which was created by the International Technology Education Association. The author points out that in order for such a curriculum to be successful it …

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Curricular Value And Instructional Needs For Infusing Engineering Design Into K-12 Technology Education, David K. Gattie, Robert C. Wicklein Jan 2007

Curricular Value And Instructional Needs For Infusing Engineering Design Into K-12 Technology Education, David K. Gattie, Robert C. Wicklein

Publications

An overarching objective of Technology Education in the U.S. is to improve technological literacy among K-12 students (DeVore, 1964; Savage and Sterry, 1990; International Technology Education Association, 1996, 2000, 2003). This is addressed in part through a focus on end-product technology and the use and importance of various technologies in society (Savage and Sterry, 1990). While such a focus is certainly necessary, it may not be sufficient if the objective is to infuse engineering into the technology education field. Current efforts at the University of Georgia propose adjusting the focus of Technology Education to a defined emphasis on engineering design …

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Critical Features Of Engineering Design In Technology Education, Paul A. Asunda, Roger Hill Jan 2007

Critical Features Of Engineering Design In Technology Education, Paul A. Asunda, Roger Hill

Publications

The purpose of this study was to find critical features of engineering design that can be incorporated within technology education learning activities, and develop a rubric for assessing these features. Data were collected through semi-structured interviews with three professors actively involved in engineering education. Supporting documents such as engineering design course outlines and rubrics were also examined. Using a phenomenological approach, this study identified the concept of engineering design, key features of the engineering design process, and critical elements that should be assessed in an engineering design activity in the context of technology education. A key product of the study …

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Moistened Seeds Increase Rodent Trap Success, Michael W. Sears, John C. Tull Jan 2007

Moistened Seeds Increase Rodent Trap Success, Michael W. Sears, John C. Tull

Publications

Seed moisture has been shown to influence the rates of seed cache removal by rodents. Although the precise mechanism is not known, this knowledge might prove useful in field applications. We examined whether moistened bait would increase trap success in desert rodent populations. We placed traps 15 m apart in grids within a 500-ha study area and randomly baited traps with either dry or moistened seeds. We found that traps baited with moistened seeds had 34.9% higher success than traps baited with dry seeds (n = 190, Χ2 = 5.389, df = 1, P = 0.020). Our results …

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Wind Damage And Salinity Effects Of Hurricanes Katrina And Rita On Coastal Baldcypress Forests Of Louisiana, William Conner, Thomas W. Doyle, Richard H. Day, Ken W. Krauss, Christopher M. Swarzenski Jan 2007

Wind Damage And Salinity Effects Of Hurricanes Katrina And Rita On Coastal Baldcypress Forests Of Louisiana, William Conner, Thomas W. Doyle, Richard H. Day, Ken W. Krauss, Christopher M. Swarzenski

Publications

The frequency of hurricane landfall in a given coastal stretch may play a more important role in the ecology of coastal forests than previously thought because of direct and indirect impacts of fallen trees and the introduction of salt water that lingers long after the storm passes. Findings show that surge events can inundate interior freshwater forests many miles from the coast and elevate soil salinities twofold to threefold. These elevated salinities may contribute to delayed mortality of certain tree species and set the stage for eventual forest decline and dieback.

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Science And The Storms: The Usgs Response To The Hurricanes Of 2005 - Chapter Six: Ecological Impacts, William Conner, Stephen Faulkner, Wylie Barrow, Brady Couvillion, Lori Randall, Michael Baldwin Jan 2007

Science And The Storms: The Usgs Response To The Hurricanes Of 2005 - Chapter Six: Ecological Impacts, William Conner, Stephen Faulkner, Wylie Barrow, Brady Couvillion, Lori Randall, Michael Baldwin

Publications

Ecological impacts from the hurricanes of 2005 affected both vegetation and the animals that depend on coastal habits on land and in water. Discussed in this section are migratory birds, coastal marsh vegetation, chenier forests, coastal floodplain forests, mangrove forests, estuaries, and the endangered manatee.

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Reviewed Work(S): Las Huellas De La Guerra Civil. Mito Y Trauma En La Narrativa De Laespaña Democrática By Carmen Moreno-Nuño, Salvador Oropesa Jan 2007

Reviewed Work(S): Las Huellas De La Guerra Civil. Mito Y Trauma En La Narrativa De Laespaña Democrática By Carmen Moreno-Nuño, Salvador Oropesa

Publications

No abstract provided.

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Spin-Hall Conductivity Of A Spin-Polarized Two-Dimensional Electron Gas With Rashba Spin-Orbit Interaction And Magnetic Impurities, D C. Marinescu, C P. Moca Jan 2007

Spin-Hall Conductivity Of A Spin-Polarized Two-Dimensional Electron Gas With Rashba Spin-Orbit Interaction And Magnetic Impurities, D C. Marinescu, C P. Moca

Publications

The Kubo formula is used to calculate the spin-Hall conductivity σsH in a spin-polarized two-dimensional electron system with Rashba-type spin– orbit interaction. As in the case of the unpolarized electron system, σsH is entirely determined by states at the Fermi level, a property that persists in the presence of magnetic impurities. In the clean limit, the spin-Hall conductivity decreases monotonically with the Zeeman splitting, a result of the ordering effect on the electron spins produced by the magnetic field. In the presence of magnetic impurities, the spin-dependent scattering determines a finite renormalization of the static part of the fully dressed …

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Impulsive-Actuation Part Positioning Through Constrained Energy Balance Planning, Laine Mears, Thomas R. Kurfess Jan 2007

Impulsive-Actuation Part Positioning Through Constrained Energy Balance Planning, Laine Mears, Thomas R. Kurfess

Publications

Impulsive actuation has been researched in the past two decades as an inexpensive alternative to multi-degree-of-freedom precision positioning systems. The position of a sliding workpiece can be controlled by a 2-degree-offreedom actuation system through simple pushing path planning. However, the final part position as a result of the last touch of the actuator is subject to uncertainty in the friction model used for actuation planning, particularly the free-sliding distance undergone by the workpiece after losing contact with the actuator. This paper first reviews an impact planning method, then augments it using a restitutionbased model that results in an explicit actuator …

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Erratum: Selective Blockade Of The Inhibitory Fcγ Receptor (Fcγriib) In Human Dendritic Cells And Monocytes Induces A Type I Interferon Response Program, Madhav V. Dhodapkar, Devi K. Banerjee, John E. Connolly Jan 2007

Erratum: Selective Blockade Of The Inhibitory Fcγ Receptor (Fcγriib) In Human Dendritic Cells And Monocytes Induces A Type I Interferon Response Program, Madhav V. Dhodapkar, Devi K. Banerjee, John E. Connolly

Publications

[No abstract available]

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Normal Human Dermis Contains Distinct Populations Of Cd11c +Bdca-1+ Dendritic Cells And Cd163+Fxiiia + Macrophages, Lisa C. Zaba, Judilyn Fuentes-Duculan, Ralph M. Steinman Jan 2007

Normal Human Dermis Contains Distinct Populations Of Cd11c +Bdca-1+ Dendritic Cells And Cd163+Fxiiia + Macrophages, Lisa C. Zaba, Judilyn Fuentes-Duculan, Ralph M. Steinman

Publications

We used a panel of monoclonal antibodies to characterize DCs in the dermis of normal human skin. Staining for the CD11c integrin, which is abundant on many kinds of DCs, revealed cells in the upper dermis. These cells were positive for blood DC antigen-1 (BDCA-1; also known as CD1c), HLA-DR, and CD45, markers that are also expressed by circulating myeloid DCs. A small subset of CD11c + dermal cells expressed DEC-205/CD205 and DC-lysosomal-associated membrane glycoprotein/CD208 (DC-LAMP/CD208), suggesting some differentiation or maturation. When BDCA-1+ cells were selected from collagenase digests of normal dermis, they proved to be strong stimulators for …

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