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The human pathogen Mycobacterium tuberculosis (Mtb) encodes 20 cytochrome P450 (P450) enzymes. Gene essentiality for viability or host infection was demonstrated for Mtb P450s CYP128, CYP121 and CYP125. Structure/function studies on Mtb P450s revealed key roles contributing to bacterial virulence and persistence in the host. Various azole-class drugs bind with high affinity to the Mtb P450 heme and are potent Mtb antibiotics. This paper reviews the current understanding of the biochemistry of Mtb P450s, their interactions with azoles and their potential as novel Mtb drug targets. Mtb multidrug resistance is widespread and novel therapeutics are desperately needed. Simultaneous drug targeting of several Mtb P450s crucial to bacterial viability/persistence could offer a new route to effective antibiotics and minimize the development of drug resistance.

Efforts to assure high-quality, safe, clinical care depend upon capturing information about near-miss and adverse outcome events. Inconsistent or unreliable information capture, especially for infrequent events, compromises attempts to analyze events in quantitative terms, understand their implications, and assess corrective efforts. To enhance reporting, we developed a secure, electronic, mandatory system for reporting quality assurance data linked to our electronic anesthesia record.We used the capabilities of our anesthesia information management system (AIMS) in conjunction with internally developed, secure, intranet-based, Web application software. The application is implemented with a backend allowing robust data storage, retrieval, data analysis, and reporting capabilities. We customized a feature within the AIMS software to create a hard stop in the documentation workflow before the end of anesthesia care time stamp for every case. The software forces the anesthesia provider to access the separate quality assurance data collection program, which provides a checklist for targeted clinical events and a free text option. After completing the event collection program, the software automatically returns the clinician to the AIMS to finalize the anesthesia record.The number of events captured by the departmental quality assurance office increased by 92% (95% confidence interval [CI] 60.4%-130%) after system implementation. The major contributor to this increase was the new electronic system. This increase has been sustained over the initial 12 full months after implementation. Under our reporting criteria, the overall rate of clinical events reported by any method was 471 events out of 55,382 cases or 0.85% (95% CI 0.78% to 0.93%). The new system collected 67% of these events (95% confidence interval 63%-71%).We demonstrate the implementation in an academic anesthesia department of a secure clinical event reporting system linked to an AIMS. The system enforces entry of quality assurance information (either no clinical event or notification of a clinical event). System implementation resulted in capturing nearly twice the number of events at a relatively steady case load.

We demonstrate the hohlraum radiation temperature and symmetry required for ignition-scale inertial confinement fusion capsule implosions. Cryogenic gas-filled hohlraums with 2.2 mm-diameter capsules are heated with unprecedented laser energies of 1.2 MJ delivered by 192 ultraviolet laser beams on the National Ignition Facility. Laser backscatter measurements show that these hohlraums absorb 87% to 91% of the incident laser power resulting in peak radiation temperatures of T(RAD)=300 eV and a symmetric implosion to a 100 μm diameter hot core.

The neurovascular system may be viewed as a distributed nervous system within the brain. It transforms local neuronal activity into a change in the tone of smooth muscle that lines the walls of arterioles and microvessels. We review the current state of neurovascular coupling, with an emphasis on signaling molecules that convey information from neurons to neighboring vessels. At the level of neocortex, this coupling is mediated by: (i) a likely direct interaction with inhibitory neurons, (ii) indirect interaction, via astrocytes, with excitatory neurons, and (iii) fiber tracts from subcortical layers. Substantial evidence shows that control involves competition between signals that promote vasoconstriction versus vasodilation. Consistent with this picture is evidence that, under certain circumstances, increased neuronal activity can lead to vasoconstriction rather than vasodilation. This confounds naïve interpretations of functional brain images. We discuss experimental approaches to detect signaling molecules in vivo with the goal of formulating an empirical basis for the observed logic of neurovascular control.

Data taken during the final shallow-site run of the first tower of the Cryogenic Dark Matter Search (CDMS II) detectors have been reanalyzed with improved sensitivity to small energy depositions. Four ~224 g germanium and two ~105 g silicon detectors were operated at the Stanford Underground Facility (SUF) between December 2001 and June 2002, yielding 118 live days of raw exposure. Three of the germanium and both silicon detectors were analyzed with a new low-threshold technique, making it possible to lower the germanium and silicon analysis thresholds down to the actual trigger thresholds of ~1 keV and ~2 keV, respectively. Limits on the spin-independent cross section for weakly interacting massive particles (WIMPs) to elastically scatter from nuclei based on these data exclude interesting parameter space for WIMPs with masses below 9 GeV/c^2. Under standard halo assumptions, these data partially exclude parameter space favored by interpretations of the DAMA/LIBRA and CoGeNT experiments' data as WIMP signals, and exclude new parameter space for WIMP masses between 3 GeV/c^2 and 4 GeV/c^2., 18 pages, 12 figures, 5 tables

The Mycobacterium tuberculosis cytochrome P450 enzyme CYP142 is encoded in a large gene cluster involved in metabolism of host cholesterol. CYP142 was expressed and purified as a soluble, low spin P450 hemoprotein. CYP142 binds tightly to cholesterol and its oxidized derivative cholest-4-en-3-one, with extensive shift of the heme iron to the high spin state. High affinity for azole antibiotics was demonstrated, highlighting their therapeutic potential. CYP142 catalyzes either 27-hydroxylation of cholesterol/cholest-4-en-3-one or generates 5-cholestenoic acid/cholest-4-en-3-one-27-oic acid from these substrates by successive sterol oxidations, with the catalytic outcome dependent on the redox partner system used. The CYP142 crystal structure was solved to 1.6 Å, revealing a similar active site organization to the cholesterol-metabolizing M. tuberculosis CYP125, but having a near-identical organization of distal pocket residues to the branched fatty acid oxidizing M. tuberculosis CYP124. The cholesterol oxidizing activity of CYP142 provides an explanation for previous findings that ΔCYP125 strains of Mycobacterium bovis and M. bovis BCG cannot grow on cholesterol, because these strains have a defective CYP142 gene. CYP142 is revealed as a cholesterol 27-oxidase with likely roles in host response modulation and cholesterol metabolism.

Cholic acid derivatives appended with amine groups have been prepared for use as permeabilizers of the outer membranes of Gram-negative bacteria. These compounds interact synergistically with antibiotics such as erythromycin and novobiocin to inhibit growth of Gram-negative bacteria. When a hydrophobic chain is included on the permeabilizers, they can be converted into potent antibiotics. The role of the hydrophobic chain is to facilitate self-promoted transport of the cholic acid derivatives across the outer membrane of Gram-negative bacteria. These compounds share activities found with polymyxin B and derivatives.

Rapid laboratory methods provide optimal support for active surveillance efforts to screen for methicillin-resistant Staphylococcus aureus (MRSA). Most laboratories struggle to determine the optimal use of resources, considering options to balance cost, speed, and diagnostic accuracy. To assess the performance of common methods, the first comparison of MRSASelect agar (MS) and CHROMagar MRSA (CA), with and without broth enrichment followed by a 24-h subculture to MS, was performed. Results were compared to those of the Xpert MRSA assay. For direct culture methods, the agreement between MS and CA was 98.8%. At 18 h, direct MS identified 93% of all positive samples from direct culture and 84% of those identified by the Xpert MRSA. For Trypticase soy broth-enriched MS culture, incubated overnight and then subcultured for an additional 24 h, the agreement with Xpert MRSA was 96%. The agreement between direct MS and Xpert MRSA was 100% when semiquantitative culture revealed a bacterial density of 2+ or greater; however, discrepancies between culture and Xpert MRSA arose for MRSA bacterial densities of 1+ or less, indicating low density as a common cause of false-negative culture results. Since 1+ or less was established as the most common MRSA carrier state, broth enrichment or PCR may be critical for the identification of all MRSA carriers who may be reservoirs for transmission. In this active-surveillance convenience sample, the use of broth enrichment followed by subculture to MS offered a low-cost but sensitive method for MRSA screening, with performance similar to that of Xpert MRSA PCR.

Blood is a limited resource that supplies neurons and glia with nutriments. How is blood distributed both in a fail-safe way and in response to changing metabolic loads? We examine this issue in rodent cortex. First, in terms of topology, all-optical histology is used to reconstruct the vasculature network. Second, in terms of dynamics, the flux of blood cells in individual vessels is measured in response to neuronal activation and/or the perturbation of flow of a targeted vessel via plasma-mediated ablation. Lastly, in terms of control, optical indicators of neurovascular signaling molecules that alter vessel diameter are measured.

We have used the STACEE high-energy gamma-ray detector to look for fast blue-green laser pulses from the vicinity of 187 stars. The STACEE detector offers unprecedented light-collecting capability for the detection of nanosecond pulses from such lasers. We estimate STACEE's sensitivity to be approximately 10 photons per square meter at a wavelength of 420 nm. The stars have been chosen because their characteristics are such that they may harbor habitable planets and they are relatively close to Earth. Each star was observed for 10 minutes and we found no evidence for laser pulses in any of the data sets., 38 pages, 12 figures. Accepted for publication in Astrobiology

The purpose of this study was to determine whether high flexion leads to improved benefits in patient satisfaction, perception, and function after total knee arthroplasty (TKA). Data were collected on 122 primary TKAs. Patients completed a Total Knee Function Questionnaire. Knees were classified as low (≤110°), mid (111°-130°), or high flexion (N130°). Correlation between knee flexion and satisfaction was not statistically significant. Increased knee flexion had a significant positive association with achievement of expectations, restoration of a "normal" knee, and functional improvement. In conclusion, although the degree of postoperative knee flexion did not affect patient satisfaction, it did influence fulfillment of expectations, functional ability, and knee perception. This suggests that increased knee flexion, particularly more than 130°, may lead to improved outcomes after TKA. Keywords: total knee arthroplasty, patient-derived outcomes, patient satisfaction, high flexion, function. © 2011 Elsevier Inc. All rights reserved.

The potential of chemicals to cause developmental neurotoxicity has generated considerable interest in recent years. The U. S. Environmental Protection Agency (EPA) has published a general guideline for developmental neurotoxicity testing. The guidelines reflect discussions and input from scientists representing academia, industry, and regulatory sectors. While consensus has not been achieved on a number of parametric and semantic details, the guidelines provide a starting point for establishing a standard protocol for assessing the potential effects of perinatal chemical exposure on the integrity of the nervous system. The EPA guideline will be outlined and issues which remain somewhat controversial will be discussed (e.g., definitions, screening versus characterization, criteria for selecting chemicals for testing, dose selection criteria, exposure period, and data interpretation). In addition, alternative approaches for generating developmental neurotoxicity screening data will be reviewed.

The skin reflectance of 556 Andean Indians of Aymara ancestry (305 males, 251 females; 10.0-29.9 yr) residing in La Paz, Bolivia (average altitude of about 3,600 m) is described. Reflectances were measured at three wavelengths (425 nm, 545 nm, and 685 nm) on two different sites, the medial surface of the upper arm and forehead. Males tended to be significantly darker than females on both the upper arm and forehead (P < .05). Female Aymara tended to lighten significantly in skin color with age on both the upper arm and forehead, while males tended to lighten significantly with age only on the upper arm (P < .05). The results of comparisons between three categories based on paternal and maternal surnames (two Aymara surnames, one Aymara and one Spanish surname, and two Spanish surnames) were consistent with the hypothesis that the possession of Spanish surnames is positively related to the degree of European admixture in urban Aymara. However, the extent of admixture within each surname category may differ between rural and urban Aymara, making classification by surnames problematic for rural-urban comparisons.

For some time, the Draco dwarf spheroidal galaxy has garnered interest as a possible source for the indirect detection of dark matter. Its large mass-to-light ratio and relative proximity to the Earth provide favorable conditions for the production of a detectable flux of gamma rays from dark matter self-annihilation in its core. The Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE) is an atmospheric Cherenkov telescope located in Albuquerque, NM capable of detecting gamma rays at energies above 100 GeV. We present the results of the STACEE observations of Draco during the 2005-2006 observing season totaling 10.2 hours of live time after cuts. We do not detect a significant gamma-ray signal from Draco, and place an upper limit on a power-law spectrum of (dN/dE)|{sub Draco} ) for weakly interacting massive particles self-annihilation.

Businesses of every size and type are involved in blogging – a novel and changing form of corporate communication that resides in an unsettled legal world. These blogs come in different varieties. Some are written by CEOs or other C-suite executives. Some are written by employees with a particular expertise. Some are directly supported, even hosted on the web, by the corporation. Some claim to be independent of any corporate influence, control or editing. Some are simply silent on those questions. Practitioners of businesses and public relations cannot safely treat any of these corporate blogs as fully-protected First Amendment speech. This study examines the legal issues stemming from various kinds of corporate blogs, analyzes the impact of legal issues on corporate and public relations blogging, and suggests a methodology for classifying various blogs and evaluating the risks presented by each.

Much is known about the potential consequences of prenatal alcohol exposure through data developed in animals and man. However, little attempt has been made to compare the human and animal literature with respect to qualitative and quantitative similarities and differences. To this end, a comparison was made between the effects reported in humans following moderate levels of alcohol exposure and the neurobehavioral effects detected using animal models. A good deal of congruence was found with respect to qualitative endpoints. General functional categories, such as deficits in learning, inhibition, attention, regulatory behaviors, and motor performance were reported to be affected in both animals and children. Quantitatively, although the dose required to produce an effect differs across species, the resultant circulating blood alcohol levels are quite similar. In addition, while compelling data are limited, the magnitude of the observed effects are generally dose-related for both humans and animals.

Background: Documentation of key times and events is required to obtain reimbursement for anesthesia services. The authors installed an information management system to improve record keeping and billing performance but found that a significant number of their records still could not be billed in a timely manner, and some records were never billed at all because they contained documentation errors. Methods: Computer software was developed that automatically examines electronic anesthetic records and alerts clinicians to documentation errors by alphanumeric page and email. The software’s efficacy was determined retrospectively by comparing billing performance before and after its implementation. Staff satisfaction with the software was assessed by survey. Results: After implementation of this software, the percentage of anesthetic records that could never be billed declined from 1.31% to 0.04%, and the median time to correct documentation errors decreased from 33 days to 3 days. The average time to release an anesthetic record to the billing service decreased from 3.0 0.1 days to 1.1 0.2 days. More than 90% of staff found the system to be helpful and easier to use than the previous manual process for error detection and notification. Conclusion: This system allowed the authors to reduce the median time to correct documentation errors and the number of anesthetic records that were never billed by at least an order of magnitude. The authors estimate that these improvements increased their department’s revenue by approximately $400,000 per year. TO obtain reimbursement for anesthesia services in the United States, clear and complete billing documentation is required. This documentation includes specific time and event elements relating to the preanesthetic evaluation, intraanesthetic management, and postanesthetic care. The absence of even a single element or the presence of a wrong element can lead to the rejection of a claim for services rendered. Therefore, it is important that anesthesia practices identify and correct such documentation errors on anesthesia records to maximize revenues. Beyond its primary importance for revenue generation, billing documentation can also provide valuable evidence of proper medical care. 1 Achieving the goal of clear and complete documentation in every anesthetic record is a challenge, particularly in settings where anesthesiologists simultaneously direct the care of multiple patients and their primary focus of attention is on patient care and teaching. The advent of computerized anesthesia information management systems (AIMS) provides opportunities to develop novel tools and solutions to persistent problems in anesthesia practice, especially those related to consistent task execution and completion. Recently, it has been demonstrated that computerized automatic process monitoring and automatic alerts yield clinically important improvements in outcomes when applied to medical orders. 2,3 This suggests that other aspects of the care process, including seemingly mundane tasks such as billing documentation, would benefit from this approach. In the beginning of 2003, our department transitioned from recording intraoperative patient data using pen and paper to using an AIMS (Saturn; Draeger, Telford, PA) for documentation. The primary purpose of this transition was to facilitate correct data capture, 4 to minimize recording errors, 5 and to reduce the cost and time associated with generating bills by simplifying the billing process. However, after the transition to this system, it was apparent that a significant number of our records could not be submitted for payment even months after the date of service because they contained deficiencies and errors related to documentation that precluded billing. We hypothesized that we could reduce documentation errors, improve billing performance, and capture lost revenue by developing software and instituting a computerized system that would automatically search electronic anesthetic records for documentation errors and alert anesthesia personnel in near real time. This report describes this system, its implementation, and its impact on our documentation and billing performance.

Primary fallopian tube carcinoma is a rare tumor. The aim of this study was to evaluate clinical characteristics and management of fallopian tube malignancies at a large tertiary care cancer institute.A retrospective review of the Tumor Registry was conducted to identify all primary fallopian tube carcinomas between 1980 and 2001. Medical charts were retrospectively reviewed. Primary endpoints were overall survival and disease recurrence.Thirty-five patients had histology consistent with fallopian tube carcinoma. The median age at diagnosis was 56 years. The most common signs or symptoms were abnormal vaginal bleeding (29%) and abdominal/pelvic mass (26%). The most common histology was adenocarcinoma in 16 (46%) patients. Five patients (14%) were Stage I, seven patients (20%) Stage II, 17 patients (49%) Stage III and six patients (17%) Stage IV. Thirty-two (91%) patients received adjuvant chemotherapy and 77% received platinum-based chemotherapy. Twenty-seven (77%) patients underwent second-look surgery, of which 17 patients (63%) were positive for disease. The 5-year survival rate was 64% for Stage I, 42% for Stage II, 32% for Stage III, and 17% for Stage IV.Fallopian tube malignancies are rare and carry a poor prognosis. More extensive research needs to be performed to have definitive etiologic, diagnostic and treatment guidelines.

D.S. Akerib, M.S. Armel-Funkhouser, M.J. Attisha, L. Baudis, D.A. Bauer, P.L. Brink, R. Bunker, B. Cabrera, D.O. Caldwell, C.L. Chang, M.B. Crisler, P. Cushman, R. Dixon, M.R. Dragowsky, D.D. Driscoll, L. Duong, R. Ferril, J. Filippini, R.J. Gaitskell, D. Holmgren, M.E. Huber, S. Kamat, A. Lu, R. Mahapatra, V. Mandic, P. Meunier, N. Mirabolfathi, H. Nelson, R. Nelson, R.W. Ogburn, T.A. Perera, E. Ramberg, W. Rau, A. Reisetter, R.R. Ross, T. Saab, B. Sadoulet, J. Sander, C. Savage, R.W. Schnee, D.N. Seitz, B. Serfass, A.J. Sirois, K.M. Sundqvist, J-P.F. Thompson, G. Wang, S. Yellin, and B.A. Young

We report new results from the Cryogenic Dark Matter Search (CDMS II) at the Soudan Underground Laboratory. Two towers, each consisting of six detectors, were operated for 74.5 live days, giving spectrum-weighted exposures of 34 kg-d for germanium and 12 kg-d for silicon targets after cuts, averaged over recoil energies 10-100 keV for a WIMP mass of 60GeV/c{sup 2}. A blind analysis was conducted, incorporating improved techniques for rejecting surface events. No WIMP signal exceeding expected backgrounds was observed. When combined with our previous results from Soudan, the 90% C.L. upper limit on the spin-independent WIMP-nucleon cross section is 1.6 x 10{sup -43} cm{sup 2} from Ge, and 3 x 10{sup -42} cm{sup 2} from Si, for a WIMP mass of 60GeV/c{sup 2}. The combined limit from Ge (Si) is a factor of 2.5 (10) lower than our previous results, and constrains predictions of supersymmetric models.

The CDMS‐II collaboration’s Cold Dark Matter search presently sets the most competitive exclusion limit in the world for the direct detection of the hypothesized Weakly Interacting Massive Particles (WIMPs) that constitute the cold dark matter of the Universe. Our experiment utilizes Ge (and Si) crystals as the target detectors, each with a mass of 250 g (100 g) and cooled to 30 mK. To eliminate natural radioactive sources as background the experiment is conducted in a well‐shielded environment in the Soudan Mine, Minnesota, and has been operating for the last two years. To aid in the identification of a possible WIMP‐candidate event, the detectors are designed to measure both the ionization and athermal phonon signals produced by each candidate event. The athermal phonon signal is measured using superconducting aluminum films on the crystal surface connected to tungsten transition edge sensors. The latest WIMP‐search results from Soudan will be presented, along with projections for the future.

The Cryogenic Dark Matter Search (CDMS) is an experiment to detect weakly interacting massive particles (WIMPs) based on their interactions with Ge and Si nuclei. We report the results of an analysis of data from the first two runs of CDMS at the Soudan Underground Laboratory in terms of spin-dependent WIMP-nucleon interactions on 73Ge and 29Si. These data exclude new regions of spin-dependent WIMP-nucleon interaction parameter space, including regions relevant to spin-dependent interpretations of the annual modulation signal reported by the DAMA/NaI experiment., Comment: 5 pages, 4 figures; replacement to match published version

Markarian 421 (Mrk 421) was the first blazar detected at gamma-ray energies above 300 GeV, and it remains one of only twelve TeV blazars detected to date. TeV gamma-ray measurements of its flaring activity and spectral variability have placed constraints on models of the high-energy emission from blazars. However, observations between 50 and 300 GeV are rare, and the high-energy peak of the spectral energy distribution (SED), predicted to be in this range, has never been directly detected. We present a detection of Mrk 421 above 100 GeV as made by the Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE) during a multiwavelength campaign in early 2004. STACEE is a ground-based atmospheric Cherenkov telescope using the wavefront sampling technique to detect gamma rays at lower energies than achieved by most imaging Cherenkov telescopes. We also outline a method for reconstructing gamma-ray energies using a solar heliostat telescope. This technique was applied to the 2004 data, and we present the differential energy spectrum of Mrk 421 above 130 GeV. Assuming a differential photon flux dN/dE proportional to E^-a, we measure a spectral index a = 2.1 +/- 0.2 (statistical) +0.2/-0.1 (systematic). Finally, we discuss the STACEE spectrum in the context of the multiwavelength results from the same epoch., Comment: 16 pages, 4 figures, submitted to ApJ

The Cryogenic Dark Matter Search (CDMS-II) employs low-temperature Ge and Si detectors to seek Weakly Interacting Massive Particles (WIMPs) via their elastic scattering interactions with nuclei. Simultaneous measurements of both ionization and phonon energy provide discrimination against interactions of background particles. For recoil energies above 10 keV, events due to background photons are rejected with >99.99% efficiency. Electromagnetic events very near the detector surface can mimic nuclear recoils because of reduced charge collection, but these surface events are rejected with >96% efficiency by using additional information from the phonon pulse shape. Efficient use of active and passive shielding, combined with the the 2090 m.w.e. overburden at the experimental site in the Soudan mine, makes the background from neutrons negligible for this first exposure. All cuts are determined in a blind manner from in situ calibrations with external radioactive sources without any prior knowledge of the event distribution in the signal region. Resulting efficiencies are known to ~10%. A single event with a recoil of 64 keV passes all of the cuts and is consistent with the expected misidentification rate of surface-electron recoils. Under the assumptions for a standard dark matter halo, these data exclude previously unexplored parameter space for both spin-independent and spin-dependent WIMP-nucleon elastic scattering. The resulting limit on the spin-independent WIMP-nucleon elastic-scattering cross-section has a minimum of 4x10^-43 cm^2 at a WIMP mass of 60 GeV/c^2. The minimum of the limit for the spin-dependent WIMP-neutron elastic-scattering cross-section is 2x10^-37 cm^2 at a WIMP mass of 50 GeV/c^2., 37 pages, 42 figures

Antidot lattices with top and back gate tunability allow the electronic transport properties of a sample to be studied at a constant electron density while the two-dimensional electron system is shifted in the z direction. The antidot potential is found to remain essentially unaltered in our sample during a constant density sweep, while other parameters such as the background mobility or wave function symmetry in the z direction vary. The impact of these changes on the classical commensurability peaks, the Aharonov-Bohm-type oscillations, and on a weak-localization-type feature around B=0 T are investigated. In addition, a peak splitting appears in oscillations superimposed on the main commensurability peak at high electron densities.

The Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE) is a ground‐based atmospheric Cherenkov telescope for the detection of very high energy gamma rays from Galactic and extra‐galactic sources. By utilizing the large collection area provided by the solar mirrors of the National Solar Thermal Test Facility in Albuquerque, New Mexico, STACEE achieves a low energy threshold, around 100 GeV, for the detection of gamma rays. We briefly describe the STACEE detector and detail recent observations of Active Galactic Nuclei.

A double dot system with integrated charge readout is fabricated by combining direct oxidation of the GaAs surface of a Ga[Al]As‐heterostructure with the local oxidation of a thin titanium film evaporated on top. The charge stability diagram is measured in direct transport through the dots as well as in the detector signal.

The number of adults using the Internet to find and read news online is on the rise. One national study by the Pew Research Center reported that weekly use of online news tripled from 11 million to 36 million people in the United States between 1996 and 1998, which the center called “astonishing” (Pew Research Center for People & the Press, 1998). Other studies have shown similar growth in use of the Internet, the World Wide Web, and other online information resources (see, e.g., Jupiter Media Metrix, 2001; Nielsen Media Research, 1999).

In 1948, the Port of Newport sank two flat-bottom concrete ships in Yaquina Bay, Oregon, to serve as wharves for cargo handling. Prior to sinking the ships, a minimum amount of subgrade preparation was performed by excavating relatively flat benches into the Recent alluvial sand and underlying marine sedimentary rocks. The ships were then floated into place parallel to the by shore and sunk by blasting holes in their sides and bottoms. The ship hulls and the area between the hulls and the shore were subsequently backfilled and dredged with sand. The holes in the hulls and bottom of the ships remained open, which allowed the flow of water into and out of the hulls with the fluctuating tides. Port of Newport records indicate that over the past 30 years, the westernmost hull has moved episodically about 3 feet southward toward the bay, resulting in settlement of the dredged sand backfill, damage to the laydown area pavements, structural damage to the hull, and considerable maintenance expenditures. The easternmost hull has reportedly been stable. In 2000, a geotechnical investigation was undertaken to identify the conditions causing movement of the hull and to determine whether the movement was occurring at the subgrade-ship interface or whether there was a deep-seated failure occurring in the marine sedimentary rock and the results are presented in this paper.

SSGPO has developed a novel dual octave hyperspectral imaging spectrometer. To address the critical parameters of weight, volume and power consumption the system concept combines ultralightweight Sic optics and structures for front-end telescope and spectrometer, emerging dual-band FPA technology and micro dewar I electronics to form the sensor engine and a novel spectrometer ,design form which utilizes the first and second diffractive orders from a flat blazed grating. An all aluminum ground demonstration spectrometer was designed, fabricated and tested. This cost effective hardware solution consisted of a 4-mirror spectrometer design form with a replicated flat blazed grating, B2.35 at the slit and f/4 at the image plane. The optical design provided hyperspectral imagery in two spectral bands simultaneously, 3.5 to 6 microns (mid-wave infrared) and 7 to 12 microns (long-wave infrared) for a focal plane array format of 320 spectral bands and 240 spatial bands. The delivered hardware provided U10 RMS wavefront error at 3 microns. The dual octave spectrometer provides a significant improvement in the weight, volume, and power requirements for hyperspectral imaging spectrometers. This development will enable next generation surveillance and reconnaissance optical instruments for space and air based platforms.

The Cryogenic Dark Matter Search (CDMS) uses cryogenically-cooled detectors made of germanium and silicon in an attempt to detect dark matter in the form of Weakly-Interacting Massive Particles (WIMPs). The expected interaction rate of these particles is on the order of 1/kg/day, far below the 200/kg/day expected rate of background interactions after passive shielding and an active cosmic ray muon veto. Our detectors are instrumented to make a simultaneous measurement of both the ionization energy and thermal energy deposited by the interaction of a particle with the crystal substrate. A comparison of these two quantities allows for the rejection of a background of electromagnetically-interacting particles at a level of better than 99.9%. The dominant remaining background at a depth of {approx} 11 m below the surface comes from fast neutrons produced by cosmic ray muons interacting in the rock surrounding the experiment. Contamination of our detectors by a beta emitter can add an unknown source of unrejected background. In the energy range of interest for a WIMP study, electrons will have a short penetration depth and preferentially interact near the surface. Some of the ionization signal can be lost to the charge contacts there and a decreased ionization signal relativemore » to the thermal signal will cause a background event which interacts at the surface to be misidentified as a signal event. We can use information about the shape of the thermal signal pulse to discriminate against these surface events. Using a subset of our calibration set which contains a large fraction of electron events, we can characterize the expected behavior of surface events and construct a cut to remove them from our candidate signal events. This thesis describes the development of the 6 detectors (4 x 250 g Ge and 2 x 100 g Si) used in the 2001-2002 CDMS data run at the Stanford Underground Facility with a total of 119 livedays of data. The preliminary results presented are based on the first use of a beta-eliminating cut based on a maximum-likelihood characterization described above.« less

Three terminal tunnelling experiments on quantum dots in the Coulomb blockade regime allow a quantitative determination of the coupling strength of individual quantum states to the leads. Exploiting this insight we have observed independent fluctuations of the coupling strengths as a function of electron number and magnetic field due to changes in the shape of the wave function in the dot. Such a detailed understanding and control of the dot-lead coupling can be extended to more complex systems such as coupled dots, and is essential for building functional quantum electronic systems., Comment: 7 pages, 4 figures

An excitonic blue-shift is observed when a GaAs/AlGaAs superlattice is irradiated with a strong THz field. This observation is compared with a microscopic calculation, and is consistent with the onset of dynamical localization

We report the first results from a search for weakly interacting massive particles (WIMPs) in the Cryogenic Dark Matter Search (CDMS) experiment at the Soudan Underground Laboratory. Four Ge and two Si detectors were operated for 52.6 live days, providing 19.4 kg-d of Ge net exposure after cuts for recoil energies between 10--100 keV. A blind analysis was performed using only calibration data to define the energy threshold and selection criteria for nuclear-recoil candidates. Using the standard dark-matter halo and nuclear-physics WIMP model, these data set the world's lowest exclusion limits on the coherent WIMP-nucleon scalar cross-section for all WIMP masses above 15 GeV, ruling out a significant range of neutralino supersymmetric models. The minimum of this limit curve at the 90% C.L. is 4 x 10^{-43} cm^2 at a WIMP mass of 60 GeV., Comment: 4 pages, 5 figures, submitted to Phys. Rev. Lett; minor clarifications in response to referee's comments

Using improved Ge and Si detectors, better neutron shielding, and increased counting time, the Cryogenic Dark Matter Search (CDMS) experiment has obtained stricter limits on the cross section of weakly interacting massive particles (WIMPs) elastically scattering from nuclei. Increased discrimination against electromagnetic backgrounds and reduction of neutron flux confirm WIMP-candidate events previously detected by CDMS were consistent with neutrons and give limits on spin-independent WIMP interactions which are >2X lower than previous CDMS results for high WIMP mass, and which exclude new parameter space for WIMPs with mass between 8-20 GeV/c^2., 4 pages, 4 figures

An air-core, synchronous motor with a high temperature superconducting field winding has been successfully constructed and tested. The motor features a salient-pole superconducting field winding that operates at a nominal temperature of 30 K. A closed-loop (reverse Brayton cycle) cryogenic refrigeration system is used for initial cooldown and normal operation. Designed for 1,000 hp, this motor was demonstrated at 1,600 hp during operation at its rated speed of 1,800 RPM. This work summarizes the design objectives and requirements, technical challenges, data acquisition techniques and testing results.

Background Rolling circle amplification of ligated probes is a simple and sensitive means for genotyping directly from genomic DNA. SNPs and mutations are interrogated with open circle probes (OCP) that can be circularized by DNA ligase when the probe matches the genotype. An amplified detection signal is generated by exponential rolling circle amplification (ERCA) of the circularized probe. The low cost and scalability of ligation/ERCA genotyping makes it ideally suited for automated, high throughput methods. Results A retrospective study using human genomic DNA samples of known genotype was performed for four different clinically relevant mutations: Factor V Leiden, Factor II prothrombin, and two hemochromatosis mutations, C282Y and H63D. Greater than 99% accuracy was obtained genotyping genomic DNA samples from hundreds of different individuals. The combined process of ligation/ERCA was performed in a single tube and produced fluorescent signal directly from genomic DNA in less than an hour. In each assay, the probes for both normal and mutant alleles were combined in a single reaction. Multiple ERCA primers combined with a quenched-peptide nucleic acid (Q-PNA) fluorescent detection system greatly accellerated the appearance of signal. Probes designed with hairpin structures reduced misamplification. Genotyping accuracy was identical from either purified genomic DNA or genomic DNA generated using whole genome amplification (WGA). Fluorescent signal output was measured in real time and as an end point. Conclusions Combining the optimal elements for ligation/ERCA genotyping has resulted in a highly accurate single tube assay for genotyping directly from genomic DNA samples. Accuracy exceeded 99 % for four probe sets targeting clinically relevant mutations. No genotypes were called incorrectly using either genomic DNA or whole genome amplified sample.

T. SAAB, P.L. BRINK, L. BAUDIS, B. CABRERA, J.P. CASTLE, ANDC. CHANGDepartment of Physics, Stanford University, Stanford, CA 94350, USAR. J. GAITSKELL AND J.P. THOMSONDepartment of Physics, Brown University, Providence, RI 02912, USAD.S. AKERIB, D. DRISCOLL, S. KAMAT, T.A. PERERA, R.W. SCHNEEAND G. WANGDepartment of Physics, Case Western Reserve University, Cleveland, OH44106, USAM. B. CRISLER, R. DIXON AND D. HOLMGRENFermi National Accelerator Laboratory, Batavia, IL 60510, USAJ.H. EMES, R.R. ROSS, A. SMITH AND G.W. SMITHLawrence Berkeley National Laboratory, Berkeley, CA 94720, USAJ.M. MARTINISNational Institute of Standards and Technology, Boulder, CO 80303, USAT. SHUTTDepartment of Physics, Princeton University, Princeton, NJ 08544, USAB.A. YOUNGDepartment of Physics, Santa Clara University, Santa Clara, CA 95053, USAM.S. ARMEL, V. MANDIC, P. MEUNIER, W. RAU, B. SADOULET ANDD.N. SEITZDepartment of Physics, University of California, Berkeley, Berkeley, CA 94720

There are a large number of major military modernization initiatives in place to employ a digitized, network-centric, information-dominant fighting force in the next century. The evolution of both military and commercial information systems from platform-centric to network-centric architectures necessitates the creation of cross-platform environments for development and deployment of network-centric applications using open and industry accepted standards seamlessly across a wide range of connectivity infrastructures. To respond to this need, we have designed and established a state-of-the-art environment and associated testbeds for research, design, development, prototyping, demonstration, integration, and deployment of economical and robust dual-use military and commercial system solutions in the areas of networking and network-centric information technologies. The technical infrastructure of this environment and its various laboratories and testbeds are based on open and industry accepted standards, utilizing commercial-off-the-shelf (COTS) hardware and software components, and are consistent with the Joint Technical Architecture (JTA) and Defense Information Infrastructure (DII) architecture. The enabling technologies and applications currently being researched and investigated in this environment include such domains as advanced networking, wireless connectivity, mobile and nomadic computing, real-time multimedia communications, information security, network-centric computing, Internet technologies and electronic commerce. We describe the underlying architecture, the embedded technologies, and the capabilities of this environment.

We present an investigation of the dynamics of the inter-Landau-level (LL) excitations of a two-dimensional electron gas (2DEG) in large magnetic fields using coherent time-resolved nonlinear spectroscopy. The results are compared directly with measurements on undoped quantum wells. We observe time-dependent Coulomb coupling between the LL's induced by the 2DEG that induces a large transfer of oscillator strength to the lowest LL. The time dependence of the nonlinear response reveals non-Markovian and memory effects of the photoexcited system that cannot be understood in terms of the random phase approximation. We introduce a theoretical approach that treats the interactions of the magnetoexcitons with the 2DEG excitations and qualitatively accounts for the most salient experimental results in terms of shake-up of the 2DEG.

Following a successful demonstration of a 200 hp synchronous motor with a high-temperature superconducting (HTS) field winding, the effort continues on the development of a 1000 hp HTS motor. Under a contract with the Department of Energy, a vertically integrated team was formed for the development of large-stale industrial motors. The 1000 hp HTS motor has been strategically designed for operation from an adjustable-speed drive (ASD) using the same topology as the previously demonstrated 200 hp HTS motor (air-core AC synchronous motor with HTS field winding). It possesses all the essential features that can be scaled up to a pre-commercial prototype rated at 5000 hp. Successful demonstration of this motor will bring the HTS motor technology to a critical point where HTS motors will be comparable in size and efficiency to conventional high efficiency motors. Completion of the 1000 hp HTS motor will be followed by the development of a precommercial unit (5000 hp) to demonstrate the full benefits of HTS motors by saving half the losses of conventional motors in a package with half the volume. This paper reviews the overall design characteristics of a 1000 hp HTS motor and summarizes the development status of the motor system including its cryogenic refrigeration system.

The Cryogenic Dark Matter Search (CDMS) uses Ge and Si detectors to search for Weakly Interacting Massive Particles (WIMPs) via their elastic-scattering interaction with atomic nuclei. The present results from CDMS give limits on the spin-independent WIMP-nucleon elastic-scattering cross section that exclude previously unexplored parameter space above 10 GeV/c2. The second phase of the CDMS experiment, scheduled to start in January 2002, is expected to improve on the present sensitivity by more than two orders of magnitude.

The Ge and Si detectors developed by the Cryogenic Dark Matter Search (CDMS) II experiment rely on the simultaneous detection of athermal phonons and ionization produced by interactions in the crystal. The athermal phonons provide both the total energy deposited in an interaction and the information about the position of the interaction. We describe extracting this information from the pulse shapes in the four phonon sensors. We present the result of measurements made on a Si detector from the first CDMS II production batch. We also investigate ways of using the event position information to extract further information about the phonon signal.

The most recent CDMS data run (Run 20) was the first run in which multiple ZIP detectors were deployed. Three Si (0.100 kg each) and 3 Ge (0.250 kg each) ZIPs were run with the goals of fully testing such a configuration as well as measuring the γ, β, and n rates simultaneously with Ge and Si detectors. Calibration with γ and n sources established the bulk electron recoil leakage into the neutron band to be less than 0.2%. Low background data taken during the summer of 2000 produced a simultaneous measurement of the muon coincident neutron background with Si and Ge detectors.

The Cryogenic Dark Matter Search (CDMS) employs detectors which are capable of simultaneously measuring the ionization and phonon energies deposited by a particle collision. These detectors are 1-cm-thick, 7-cm-diameter crystals of either germanium or silicon with a thin film of aluminum and tungsten patterned on the surface. This presentation discusses the testing regimen that a typical CDMS detector undergoes before it gets approval for final installation at the CDMS II deep side in Soudan, MN which should be coming online within a year. Now that our technology is relatively stable, the main focus of our test facilities is to provide quality control for the mass production of our detectors. First, the critical temperatures of the tungsten and other basic quantities are measured in preparation for iron implantation, which will bring the Tc down to the desired range (70 mK). The same basic measurements are taken again after implantation to assure that the correct Tc was achieved. Finally, a detailed map o...