TBBL: A Tree-Based Bidding Language for Iterative Combinatorial Exchanges

We present a novel tree-based logical bidding language, TBBL, for preference elicitation in combinatorial exchanges (CEs). TBBL provides new expressiveness for two-sided markets with agents that are both buying and selling goods. Moreover, the rich semantics of TBBL allow the language to capture new structure, making it exponentially more concise than OR* and LGB for preferences that are realistic in important domains for CEs. With simple extensions TBBL can subsume these earlier languages. TBBL can also explicitly represent partial information about valuations. The language is designed such that the structure in TBBL bids can be concisely captured directly in mixed-integer programs for the allocation problem. We illustrate TBBL through examples drawn from domains to which it can be (and is being) applied, and motivate further extensions we are currently pursuing.Engineering and Applied Science

Presynaptic dopaminergic function is largely unaltered in mesolimbic and mesostriatal terminals of adult rats that were prenatally exposed to cocaine

Fast-scan cyclic voltammetry in brain slices and postmortem tissue content assessment were used to evaluate presynaptic dopaminergic function in the caudate putamen and nucleus accumbens of adult male rats (180+ days old) that were prenatally treated with either cocaine or saline. Experiments were carried out to test whether there were differences in dopamine release, reuptake, autoreceptor function or the tissue levels of dopamine and its metabolites between cocaine- and saline-exposed rats. We report that presynaptic dopaminergic function remains largely intact in adult rats that were prenatally exposed to cocaine. The ability of terminals in the caudate putamen and nucleus accumbens to release and regulate dopamine is unaltered by prenatal cocaine exposure. However the tissue content of dopamine in the caudate putamen was decreased, representing a diminution in the dopamine storage pool. We conclude, therefore, that behavioral changes that have previously been observed in rats that were prenatally exposed to cocaine are not mediated through alteration of presynaptic dopaminergic mechanisms in these brain regions

The White Mountain Polarimeter Telescope and an Upper Limit on CMB Polarization

The White Mountain Polarimeter (WMPol) is a dedicated ground-based microwave telescope and receiver system for observing polarization of the Cosmic Microwave Background. WMPol is located at an altitude of 3880 meters on a plateau in the White Mountains of Eastern California, USA, at the Barcroft Facility of the University of California White Mountain Research Station. Presented here is a description of the instrument and the data collected during April through October 2004. We set an upper limit on $E$-mode polarization of 14 $\mu\mathrm{K}$ (95% confidence limit) in the multipole range $170<\ell<240$. This result was obtained with 422 hours of observations of a 3 $\mathrm{deg}^2$ sky area about the North Celestial Pole, using a 42 GHz polarimeter. This upper limit is consistent with $EE$ polarization predicted from a standard $\Lambda$-CDM concordance model.Comment: 35 pages. 12 figures. To appear in ApJ

Acute inflammatory myelopathies

Inflammatory injury to the spinal cord causes a well-recognized clinical syndrome. Patients typically develop bilateral weakness, usually involving the legs, although the arms may also become affected, in association with a pattern of sensory changes that suggests a spinal cord dermatomal level. Bowel and bladder impairment is also common in many patients. Recognition of the clinical pattern of spinal cord injury should lead clinicians to perform imaging studies to evaluate for compressive etiologies. MRI of the spine is particularly useful in helping visualize intraparenchymal lesions and when these lesions enhance following contrast administration a diagnosis of myelitis is made. Cerebrospinal fluid analysis can also confirm a diagnosis of myelitis when a leukocytosis is present. There are many causes of non-compressive spinal cord injury including infectious, parainfectious, toxic, nutritional, vascular, systemic as well as idiopathic inflammatory etiologies. This review focuses on inflammatory spinal cord injury and its relationships with multiple sclerosis, neuromyelitis optica, acute disseminated encephalomyelitis and systemic collagen vascular and paraneoplastic diseases

Use of a Human Visual System Model to Predict Observer Performance with CRT vs LCD Display of Images

This Project evaluated a human visual system model (JNDmetrix) based on just noticeable difference (JND) and frequency-channel vision-modeling principles to assess whether a Cathode ray tube (CRT) or a liquid crystal display (LCD) monochrome display monitor would yield better observer performance in radiographic interpretation. Key physical characteristics, such as veiling glare and modulation transfer function (MTF) of the CRT and LCD were measured. Regions of interest from mammographic images with masses of different contrast levels were shown once on each display to six radiologists using a counterbalanced presentation order. The images were analyzed using the JNDmetrix model. Performance as measured by receiver operating characteristic (ROC) analysis was significantly better overall on the LCD display (P = 0.0120). The JNDmetrix model predicted the result (P = 0.0046) and correlation between human and computer observers was high (r2 (quadratic) = 0.997). The results suggest that observer performance with LCD displays is superior to CRT viewing, at least for on-axis viewing

The Background Emission Anisotropy Scanning Telescope (BEAST) Instrument Description and Performances

The Background Emission Anisotropy Scanning Telescope (BEAST) is a millimeter wavelength experiment designed to generate maps of fluctuations in the cosmic microwave background (CMB). The telescope is composed of an off-axis Gregorian optical system with a 2.2 m primary that focuses the collected microwave radiation onto an array of cryogenically cooled high electron mobility transistor (HEMT) receivers. This array is composed of six corrugated scalar feed horns in the Q band (38 to 45 GHz) and two more in the Ka band (26 to 36 GHz) with one of the six Q-band horns connected to an ortho-mode transducer for extraction of both polarizations incident on the single feed. The system has a minimum beam size of 200 with an average sensitivity of 900 mu K root s per receiver. This paper describes the design and performance of the BEAST instrument and provides the details of subsystems developed and used toward the goal of generating a map of CMB fluctuations on 200 scales with sensitivity in l space between l similar to 100 and l similar to 500. A map of the CMB centered on the north celestial pole has been generated from the BEAST telescope in a 9 degrees wide annulus at declination 37 degrees with a typical pixel error of 57 +/- 5 mu K when smoothed to 300 resolution. A brief summary of the map and results generated by an observing campaign at the University of California White Mountain Research Station are also included

The Optical Design of the Background Emission Anisotropy Scanning Telescope (BEAST)

We present the optical design of the Background Emission Anisotropy Scanning Telescope (BEAST), an off-axis Gregorian telescope designed to measure the angular distribution of the cosmic microwave background radiation (CMBR) at 30 and 41.5 GHz on angular scales ranging from 20' to 10 degrees. The aperture of the telescope is 1.9 m, and our design meets the strict requirements imposed by the scientific goals of the mission: the beam size is 200 at 41.5 GHz and 260 at 30 GHz, while the illumination at the edge of the mirrors is lower than -30 dB for the central horn. The primary mirror is an off-axis section of a paraboloid, and the secondary an off-axis section of an ellipsoid. A spinning flat mirror located between the sky and the primary provides a two-dimensional chop by rotating the beams around an ellipse on the sky. BEAST uses a receiver array of cryogenic low noise InP High Electron Mobility Transistor (HEMT) amplifiers. The baseline array has seven horns matched to one amplifier each and one horn matched to two amplifiers (two polarizations) for a total of nine amplifiers. Two horns operate around 30 GHz, and six operate around 41.5 GHz. Subsequent campaigns will include 90 GHz and higher frequency channels

THE BACKGROUND EMISSION ANISOTROPY SCANNING TELESCOPE (BEAST) INSTRUMENT DESCRIPTION AND PERFORMANCES

ABSTRACT The Background Emission Anisotropy Scanning Telescope (BEAST) is a millimeter wavelength experiment designed to generate maps of fluctuations in the cosmic microwave background (CMB). The telescope is composed of an off-axis Gregorian optical system with a 2.2 m primary that focuses the collected microwave radiation onto an array of cryogenically cooled high electron mobility transistor (HEMT) receivers. This array is composed of six corrugated scalar feed horns in the Q band (38 to 45 GHz) and two more in the Ka band (26 to 36 GHz) with one of the six Q-band horns connected to an ortho-mode transducer for extraction of both polarizations incident on the single feed. The system has a minimum beam size of 20 0 with an average sensitivity of 900 K ffiffi s p per receiver. This paper describes the design and performance of the BEAST instrument and provides the details of subsystems developed and used toward the goal of generating a map of CMB fluctuations on 20 0 scales with sensitivity in l space between l $100 and l$ 500. A map of the CMB centered on the north celestial pole has been generated from the BEAST telescope in a 9 wide annulus at declination 37 with a typical pixel error of 57 AE 5 K when smoothed to 30 0 resolution. A brief summary of the map and results generated by an observing campaign at the University of California White Mountain Research Station are also included