cssi/SciSciGPT-SciSciNet huggingface dataset:
p+ Emitters on n-type c-Si using rapid thermal annealing of PECVD a-Si films and aluminum metallization

We present the development and characterization of n-type mono-Si photovoltaic cells with p+ emitters formed by the rapid thermal annealing of PECVD boron-doped amorphous silicon (a-Si) films. Aluminum metallization was deposited from evaporator and sputtering tool sources. The process yielded emitters of excellent uniformity (average non-uniformity of 4.4% over 40 samples) with sheet resistance ranging from 53 Ω/□ to 249 Ω/□ inversely dependent on the thickness of p+ film annealed. A reasonably-low post-anneal series resistance of 0.602 Ω*cm2 suggests that all-aluminum metallization is sufficient for silicon photovoltaic cells of high efficiency.
A practical framework for evaluating online distance education programs

The case is presented for distance education administrators that evaluation is an essential element of successful distance education programs. A synthesis of the program evaluation and distance education research literature is used to form a framework for conducting evaluations of online programs. Evaluators should assess student performance, determine program and cost effectiveness, monitor quality to include technology and support services, evaluate course design and instruction, and ascertain teacher and student satisfaction. Strategies tailored to obtain such information are described within the context of an open-systems approach. An inventory of potential evaluation questions for input, process, output, and impact evaluations that respond to the potential needs of internal and external stakeholders are listed along with quantitative and qualitative data requirements that can be helpful in responding to these questions.
Isotope tracer investigations of natural products biosynthesis: the discovery of novel metabolic pathways

Feeding experiments using isotopically labeled precursors remain crucial elements in the study of natural product biosynthesis. Through careful isotope tracer studies, a number of previously unrecognized biosynthetic pathways have now become obvious. One of the remarkable examples is the discovery of the non-mevalonate pathway in plants, bacteria, algae, and plasmodium, whereas others include the discovery of a new shunt pathway that connects the mevalonate pathway and branched-chain fatty acids in myxobacteria and the involvement of an unusual HMG-CoA synthase-like mechanism in polyketide biosynthesis. Significant progress has also been made in the biosynthetic studies of aminocyclitol-derived natural products and other bioactive secondary metabolites. This review highlights some of the more recent discoveries of novel mechanisms and metabolic pathways involved in natural product biosynthesis based on isotope tracer experiments. Copyright © 2007 John Wiley & Sons, Ltd.
Effects of dynamic redox zonation on the potential for natural attenuation of trichloroethylene at a fire-training-impacted aquifer

Abstract Hydrogeochemical and microbiological methods were used to characterize temporal changes along a transect of an aquifer contaminated by mixed hydrocarbon and solvent wastes from fire training activities at Wurtsmith Air Force Base (Oscoda, MI). Predominant terminal electron accepting processes (TEAPs) as measured by dissolved hydrogen indicated reoxygenation along the transect between October 1995 and October 1996, possibly because of recharge, fluctuations in water table elevation, or microbial activity. Microbiological analyses using universal and archaeal probes revealed a relationship between groundwater hydrogen concentration, TEAP, and predominant bacterial phylogeny. Specifically, a raised water table level and evidence of methanogenesis corresponded to an order of magnitude increase in archaeal 16S rRNA relative to when this zone was unsaturated. Spatial microbial and geochemical dynamics did not result in measurable differences in trichloroethylene (TCE) mineralization potential in vadose, capillary fringe, and saturated zone soils during a 500-day microcosm experiment using unprocessed contaminated soil and groundwater. Aerobic systems indicated that methane, but not toluene, may serve as a cosubstrate for TCE cometabolism. Anaerobic microcosms demonstrated evidence for methanogenesis, CO2 production and hydrogen consumption, yet dechlorination activity was only observed in a microcosm with sulfate-reduction as the dominant TEAP. Mass balance calculations indicated less than 5% mineralization, regardless of redox zone or degree of saturation, at maximum rates of 0.01–0.03 μmol/g soil·d. The general lack of dechlorination activity under laboratory conditions corroborates the limited evidence for natural dechlorination at this site, despite abundant electron donor material and accumulated organic acids from microbial degradation of alkylbenzenes. Thus, the short-term temporal dynamics in redox conditions is unlikely to have measurable effects on the long-term natural remediation potential of the aquifer.
Equipotential Surfaces and Lagrangian Points in Nonsynchronous, Eccentric Binary and Planetary Systems

We investigate the existence and properties of equipotential surfaces and Lagrangian points in nonsynchronous, eccentric binary star and planetary systems under the assumption of quasi-static equilibrium. We adopt a binary potential that accounts for nonsynchronous rotation and eccentric orbits and calculate the positions of the Lagrangian points as functions of the mass ratio, the degree of asynchronism, the orbital eccentricity, and the position of the stars or planets in their relative orbit. We find that the geometry of the equipotential surfaces may facilitate nonconservative mass transfer in nonsynchronous, eccentric binary star and planetary systems, especially if the component stars or planets are rotating supersynchronously at the periastron of their relative orbit. We also calculate the volume-equivalent radius of the Roche lobe as a function of the four parameters mentioned above. Contrary to common practice, we find that replacing the radius of a circular orbit in the fitting formula of Eggleton with the instantaneous distance between the components of eccentric binary or planetary systems does not always lead to a good approximation to the volume-equivalent radius of the Roche lobe. We therefore provide generalized analytic fitting formulae for the volume-equivalent Roche lobe radius appropriate for nonsynchronous, eccentric binary star and planetary systems. These formulae are accurate to better than 1% throughout the relevant two-dimensional parameter space that covers a dynamic range of 16 and 6 orders of magnitude in the two dimensions.
As an adjunct to tooth brushing, interdental brushes (IDBs) are more effective in removing plaque as compared with brushing alone or the combination use of tooth brushing and dental floss.

Article Title and Bibliographic Information The efficacy of interdental brushes on plaque and parameters of periodontal inflammation: a systematic review. Slot DE, Dorfer CE, Van der Weijden GA. Int J Dent Hygiene 2008;6(4):253-64. Reviewer Joan I. Gluch, RDH, PhD Purpose/Question To determine the effect of interdental brushes (IDBs) as an adjunct to tooth brushing compared with tooth brushing alone or other interdental oral hygiene devices on plaque, gingival inflammation, bleeding, and pocket depth Source of Funding Information not available Type of Study/Design Systematic review with meta-analysis of data Level of Evidence Level 2: Limited-quality patient-oriented evidence Strength of Recommendation Grade Grade B: Limited-quality patient-oriented evidence
Epithelial damage in nasal polyps

Bronchial epithelial damage occurs regularly in bronchial asthma, but it is not known whether such damage occurs in the mucosa of nasal polyps. We obtained nasal polyp tissues from thirty patients and we examined these tissues for evidence of epithelial damage. Immediately after resection, polyp tissue was fixed in Karnovsky's fixative, embedded in methacrylate and stained with Giemsa pH 6 X 5. Normal nasal tissue from eight patients undergoing nasal septal reconstruction was similarly processed. As a disease control, we examined tissue from eight patients with nasal polyps associated with cystic fibrosis. Tissues were viewed by microscopy and epithelial damage was expressed as the percent of surface involved. Twenty-eight of the thirty patients with idiopathic nasal polyps (93%) showed complete loss of nasal mucosa in varying degrees (range 3-81% of surface; mean, 29%). All patients showed evidence of some epithelial damage, either complete loss or marked desquamation (range 9-99% of surface; mean 54%). In contrast, six of eight biopsies from patients undergoing septal reconstruction and five of eight nasal polyps from patients with cystic fibrosis showed little or no evidence of epithelial damage. The results indicate that nasal polyps regularly show evidence of epithelial damage similar to that seen in bronchial asthma, and this abnormality may partly explain the rhinorrhea which is prominently associated with nasal polyps.
MAGNETIC STRUCTURE STUDIES AT BROOKHAVEN NATIONAL LABORATORY

The results of some current or recently completed investigations of magnetic structure and magnetic transitio-ns in Ni/sub 5/Er, MnSn/sub 2/, MnSe/ sub 2/, and Cr/sub 2/O/sub 3/ are prese nted. (D.C.W.)
Zeeman Effects in the Chlorine Nuclear Quadrupole Resonance in Sodium Chlorate

The Zeeman splitting of ${\mathrm{Cl}}^{35}$ nuclear quadrupole resonance lines in a single crystal of sodium chlorate has been studied in a magnetic field sufficiently large to permit detailed investigation of individual Zeeman components for various orientations of the crystal in the applied magnetic field. The observed patterns are in agreement with theoretical predictions based on a Hamiltonian involving an interaction of the nuclear electric quadrupole moment with a crystalline field having axial symmetry and the interaction of the nuclear magnetic moment with the applied magnetic field. The quadrupole interaction term ${e}^{2}\mathrm{Qq}$ was found to be 58.806\ifmmode\pm\else\textpm\fi{}0.002 Mc/sec and the effective nuclear magnetic moment was found to be 0.8215\ifmmode\pm\else\textpm\fi{}0.0001 nuclear magnetons. An upper limit for the electric asymmetry parameter $\ensuremath{\eta}$ was found to be 0.0012. The intensity variations of individual Zeeman components for different orientations of the crystal relative to the magnetic field were studied. The line width of individual Zeeman components was of the order of 900 cps.
Optimizing Timing of Surgical Correction in Patients With Severe Aortic Regurgitation: Role of Symptoms

Abstract Objectives. We sought to determine the independent effect of preoperative symptoms on survival after surgical correction of aortic regurgitation (AR). Background. Aortic valve replacement for severe AR is recommended after New York Heart Association functional class III or IV symptoms develop. However, whether severe preoperative symptoms have a negative influence on postoperative survival remains controversial. Methods. Preoperative characteristics and postoperative survival in 161 patients with functional class I or II symptoms (group 1) were compared with those in 128 patients with class III or IV symptoms (group 2) undergoing surgical repair of severe isolated AR between 1980 and 1989. Results. Compared with group 1, group 2 patients were older (p Conclusions. In the setting of severe AR, preoperative functional class III or IV symptoms are independent risk factors for excess immediate and long-term postoperative mortality. The presence of class II symptoms should be a strong incentive to consider immediate surgical correction of severe AR.
The thermal structure of the dayside upper atmosphere of venus above 125 km

A one-dimensional model of the Venus thermosphere has been constructed which includes computation of the heating efficiency of solar ultraviolet radiation, heat loss by radiation to space of infrared-active species, thermal transport by molecular and eddy conduction, and viscous dissipation. By comparing model predictions with results obtained from the Pioneer Venus Orbiter spacecraft, the results indicate that energy transport parameterized by eddy heat conduction plays a dominant role in determining thermospheric temperature. It is suggested that there exists a feedback mechanism linking heating and thermospheric circulation such that eddy cooling maintains an asymptotic temperature of about 300 K for both solar-maximum and solar-minimum conditions. The variation in thermospheric temperature with solar zenith angle, atomic oxygen-mixing ratio, rate of vibrational excitation of CO2 by ground-state O atoms, and the assumed transfer of O(1D) electronic energy to CO2 vibrational energy are also studied.
Infrared Spectra of the Subluminous Type Ia Supernova SN 1999by

Near-infrared (NIR) spectra of the subluminous Type Ia supernova SN 1999by are presented that cover the time evolution from about 4 days before to 2 weeks after maximum light. Analysis of these data was accomplished through the construction of an extended set of delayed detonation (DD) models covering the entire range of normal to subluminous SNe Ia. The explosion, light curves, and time evolution of the synthetic spectra were calculated self-consistently for each model, with the only free parameters being the initial structure of the white dwarf and the description of the nuclear burning front during the explosion. From these, one model was selected for SN 1999by by matching the synthetic and observed optical light curves, principally the rapid brightness decline. DD models require a minimum amount of burning during the deflagration phase, which implies a lower limit for the 56Ni mass of about 0.1 M☉ and consequently a lower limit for the SN brightness. The models that best match the optical light curve of SN 1999by were those with a 56Ni production close to this theoretical minimum. The data are consistent with little or no interstellar reddening [E(B-V) ≤ 0.12 mag], and we derive a distance of 11 ± 2.5 Mpc for SN 1999by, in agreement with other estimates. Without any modification, the synthetic spectra from this subluminous model match reasonably well the observed IR spectra taken on 1999 May 6, 10, 16, and 24. These dates correspond roughly to -4, 0, 6, and 14 days after maximum light. Prior to maximum, the NIR spectra of SN 1999by are dominated by products of explosive carbon burning (O, Mg) and Si. Spectra taken after maximum light are dominated by products of incomplete Si burning. Unlike the behavior of normal Type Ia SNe, lines from iron-group elements begin to show up only in our last spectrum taken about 2 weeks after maximum light. The implied distribution of elements in velocity space agrees well with the DD model predictions for a subluminous SN Ia. Regardless of the explosion model, the long duration of the phases dominated by layers of explosive carbon and oxygen burning argues that SN 1999by was the explosion of a white dwarf at or near the Chandrasekhar mass. The good agreement between the observations and the models without fine-tuning a large number of free parameters suggests that DD models are a good description of at least subluminous Type Ia SNe. Pure deflagration scenarios or mergers are unlikely, and helium-triggered explosions can be ruled out. However, problems for DD models still remain, since the data seem to be at odds with recent three-dimensional models of the deflagration phase that predict significant mixing of the inner layers of the white dwarf prior to detonation. Possible solutions include the effects of rapid rotation on the propagation of nuclear flames during the explosive phase of burning or extensive burning of carbon just prior to the runaway.
It’s All in the Name: Source Cue Ambiguity and the Persuasive Appeal of Campaign Ads

As strategies for campaign political advertising become more complex, there remains much to learn about how ad characteristics shape voter reactions to political messages. Drawing from existing literature on source credibility, we expect ad sponsorship will have meaningful effects on voter reactions to political advertisements. We test this by using an original experiment, where we expose a sample of student and non-student participants to equivalent ads and vary only the paid sponsor disclaimer at the end of the message. The only thing that differs across stimuli is whether a political candidate, a known interest group, or an unknown interest group sponsors the advertisement. Following exposure to one of these ads, participants complete a posttest battery of questions measuring the persuasiveness of the message, source credibility, and message legitimacy. We find that ads sponsored by unknown interest groups are more persuasive than those sponsored by candidates or known interest groups, and persuasion is mediated by perceived credibility of the source. We conclude by discussing our findings and their implications for our understanding of contemporary campaigns.
Proteasome inhibition in small-cell lung cancer: preclinical rationale and clinical applications.

Small-cell lung cancer (SCLC) is a tobacco-related malignancy that usually presents in an extensive and therefore incurable stage. Although initially sensitive to platinum agent–based therapy, SCLC rapidly becomes refractory to chemotherapy, leading to disease recurrence and ultimately patient death. Treatment options following failure of first-line platinum agent–based therapy are limited. Small-cell lung cancer is characterized by molecular aberrancies such as overexpression of the antiapoptotic protein Bcl-2, which is regulated in part by the inhibitory IκB, a target of the ubiquitin–proteasome degradative pathway. Bortezomib is a proteasome inhibitor that can decrease Bcl-2 expression through diminished IκB degradation. Efforts to promote apoptosis in SCLC through the integration of bortezomib into therapy are under way.
Bayes' theorem and conditional nonindependence of data in medical diagnosis

Gustafson et al. (I) note that the use of Bayes’ theorem as a tool for medical diagnosis has been the subject of much promising research, but has had “. . . little real impact on the practice of medicine.” One reason for this is an independence assumption that in practice is almost never valid. When the assumption fails, appropriate application of Bayes’ theorem requires either large quantities of data to estimate parameters or complicated expert judgements about conditional probabilities (2) must be obtained. Part I of this study examines the consequences of ignoring failure of the independence assumption in a medical diagnosis problem. Part II explores a means to partially exploit conditional non-independence. The data were collected by Russell S. Bell, M.D., and John W. Loop, M.D. (3) and kindly made available by them.
Eisenstein's choreography in Ivan the Terrible

ABSTRACTThis article deals with the dance-related layer of Eisenstein's Gesamtkunstwerk-film, Ivan the Terrible (Part 1, 1944; Part 2, 1946). Narrative and visual borrowings from the famous ballet Swan Lake, whose leading star Galina Ulanova was to play Anastasia in Ivan the Terrible, are examined in the first part of this essay. Another part discusses seemingly wild, yet meaningful and thoroughly staged steps of the oprichniki's dance in Part 2 as opposed to the majestic choreography of the wedding feast shown at the film's beginning. As argued in the final part of the article, Eisenstein chose to use choreography as a specific type of narrative, which could reveal the hidden message that the pre-censored scenario was not supposed or allowed to put into words.
Probing the Role of Active Site Residues in NikD, an Unusual Amino Acid Oxidase That Catalyzes an Aromatization Reaction Important in Nikkomycin Biosynthesis

NikD catalyzes a remarkable aromatization reaction that converts piperideine 2-carboxylate (P2C) to picolinate, a key component of the nonribosomal peptide in nikkomycin antibiotics. The enzyme exhibits a FAD−Trp355 charge-transfer band at weakly alkaline pH that is abolished upon protonation of an unknown ionizable residue that exhibits a pKa of 7.3. Stopped-flow studies of the reductive half-reaction with wild-type nikD and P2C show that the enzyme oxidizes the enamine tautomer of P2C but do not distinguish among several possible paths for the initial two-electron oxidation step. Replacement of Glu101 or Asp276 with a neutral residue does not eliminate the ionizable group, although the observed pKa is 1 or 2 pH units higher, respectively, compared with that of wild-type nikD. Importantly, the mutations cause only a modest decrease (<5-fold) in the observed rate of oxidation of P2C to dihydropicolinate. The results rule out the only possible candidates for a catalytic base in the initial two-electron oxi...
Spatial localization of the Ebola virus glycoprotein mucin-like domain determined by cryo-electron tomography

The Ebola virus glycoprotein mucin-like domain (MLD) is implicated in Ebola virus cell entry and immune evasion. Using cryo-electron tomography of Ebola virus-like particles, we determined a three-dimensional structure for the full-length glycoprotein in a near-native state and compared it to that of a glycoprotein lacking the MLD. Our results, which show that the MLD is located at the apex and the sides of each glycoprotein monomer, provide a structural template for analysis of MLD function.
Evaluation of poly{‐N‐isopropylacrylamide‐co‐[3‐(methacryloylamino)propyl]trimethylammonium} as a stationary phase for capillary electrochromatography

A cationic polyacrylamide-based stationary phase was synthesized and characterized for CEC. The stationary phase was prepared by radical copolymerization of N-isopropylacrylamide (NIPAAm) and (3-(methacryloylamino)propyl)trimethylammonium chloride (MAPTA), producing a copolymer attached to 5 microm porous silica particles. Fourier transform infrared spectroscopy and thermogravimetric analysis were used to characterize the copolymer. Under capillary electrochromatographic conditions, the poly-NIPAAm-co-MAPTA stationary phase showed to be stable in a wide pH range. The amino groups in the MAPTA provided an anodic EOF for CEC separation. The electroosmotic mobility changed less than 10% when the pH of the mobile phase was changed from 2 to 12. The run-to-run RSD of analyte migration time was less than 1.5% (n = 3), and the RSD of peak area was less than 3% (n = 3). The day-to-day RSD for migration time was less than 2% (n = 3). The polar groups present in the stationary phase contributed to the selectivity of the phase providing for hydrophilic interactions. In the separation of a series of neutral and acidic compounds, the stationary phase shows a mixed-mode separation mechanism with both hydrophobicity and hydrophilicity contributing to the separation.
Effect of Human Neural Precursor Cell Transplantation on Endogenous Neurogenesis after Focal Cerebral Ischemia in the Rat

Little is known about the relationship between neuronal cell transplantation and endogenous neurogenesis after experimental stroke. We found previously that transplantation of neuronal precursors derived from BG01 human embryonic stem cells reduced infarct volume and improved behavioral outcome after distal middle cerebral artery occlusion (MCAO) in rats. In this study, transplantation was performed 14 days after distal MCAO and doublecortin (Dcx)-expressing cells in the subventricular zone (SVZ) and subgranular zone of dentate gyrus (SGZ) were counted 60 days post-transplant. Transplantation increased neurogenesis (Dcx expression) in ipsilateral SVZ, but not in contralateral SVZ or either SGZ, in both young adult (3-month-old) and aged (24-month-old) rats. These findings suggest that cell-based therapy for stroke may be associated with changes in endogenous adaptive processes, including neurogenesis.
Feature-based approach for set-up minimization of process design from product design

Abstract The current research presents a feature-based approach to minimize the number of set-ups in the machining process planning system. It analyses machining features with a set of knowledge-based rules to determine the machining process plan for a part. In this approach, features are classified according to the number of possible tool approach directions that can be used to machine them. This divides features into two classes: single tool approach direction (STAD) features and multiple tool approach direction (MTAD) features. The process planning system groups all the STAD features with the same tool approach directions into one set-up. MTAD features are integrated, if possible, into these set-ups by choosing the appropriate tool approach direction for each MTAD feature. If this is not possible, a new set-up is created. This minimizes the total number of set-ups for machining the part. Knowledge-based rules are applied to guide the search for proper ordering between machining processes and set-ups of a part. Subsequently, a machining process plan with a minimized number of set-ups is created. The process planning system that uses this approach can serve as an integral part of a feature-based product and process design system.
CONCAT: CONflict Driven Learning in ATPG for Industrial designs

In this paper, we propose a new search technique for ATPG, called CONCAT [1], which (a) is based on AND/OR reasoning, (b) integrates conflict driven learning, and (c) avoids over specification of test vectors. The technique works seamlessly (i) between Boolean and non-Boolean gates in industrial designs, (ii) across phases in latch-based designs, (iii) between justification and propagation tasks in sequential ATPG, and (iv) across faults in the fault list. Experimental results on combinational ISCAS circuits against SAT-based ATPG, show that we can reduce the test vector specification by upto 74%, with consistent improvement in performance and capacity. We integrated the CONCAT technique into Intel's existing ATPG tool, called Aztec, and obtained upto 67% speed-up and upto 14% more ATPG effectiveness on industrial designs.
Positive and negative aspects of citation indices and journal impact factors

The Hirsch citation index h is nowadays the most frequently used numerical indicator for the performance of scientists as reflected in their output and in the reaction of the scientific community reflected in citations of individual contributions. A few of the possible improvements of h are briefly reviewed. Garfield's journal impact factor (IF) characterizes the reaction of the scientific community to publications in journals, reflected in citations of all papers published in any given journal during the preceding 2 years, and normalized against all citable articles during the same period. Again, a few of the possible improvements or supplements of IF are briefly reviewed, including the journal-h index proposed by Braun, Glanzel, and Schubert. Ascribing higher weighting factors to citations of individual papers proportionally to IF is considered to be a misuse of useful numerical indices based on citations. At most, one could turn this argument on its head and one can find reasons to ascribe an inverse proportionality relative to IF for individual citations: if a paper is considered worthy to be cited even if it was published in a low-IF journal, that citation ought to be worth more than if the citation would have been from a higher-impact journal. A weight factor reflecting the prestige of the citing author(s) may also be considered.
Characteristic imaging findings in lymphoceles of the head and neck

OBJECTIVE. Lymphoceles are benign neck cysts that are important to differentiate from congenital, infectious, and malignant cystic neck masses because they require unique surgical treatment and fol...
Using a distributed mini-computer network to automate a biochemical laboratory

This research considers a distributed system constructed by networking small computers as an appropriate architecture for the automation of laboratories having an integrated function. The simplicity, inherent reliability, and flexibility of such an architecture can be realized only if the laboratory as a whole and its proposed final operational characteristics are considered from the very beginning. This desire to automate an integrated laboratory forces us to address not only the normal problems associated with instrument automation but also the goal oriented behavior of the laboratory. We have clarified these requirements by extending the accepted characterization of instrument automation and also by characterizing the levels of interaction appropriate for laboratories which must attain successive levels of integration.Because the distributed computer system is capable of supporting either integrated or independent activities and because computing power can be added incrementally as needed, the distributed system must be viewed as a design tool easily as important as those traditionally employed. We have access to the usual tools associated with software and hardware production—e.g. translators, editors, document generators—but also the facilities to utilize them simultaneously with production programs in a reliable and flexible manner.
Momentum transfer dependence of nuclear transparency from the quasielastic 12C(e,e'p) reaction.

The cross section for quasielastic ^(12)C(e,e’p) scattering has been measured at momentum transfer Q^2=1, 3, 5, and 6.8 (GeV/c)^2. The results are consistent with scattering from a single nucleon as the dominant process. The nuclear transparency is obtained and compared with theoretical calculations that incorporate color transparency effects. No significant rise of the transparency with Q^2 is observed.
Counter-intuitive results cast in an electronic warfare framework

Four sample electronic warfare (EW) problems are described in an effort to stimulate thought on various basic issues and assumptions encountered in EW and other fields. The problems are choosing a better sensor, transmitter, sequence, and search strategy. >
Detailed design and evaluation of redundant multithreading alternatives

Exponential growth in the number of on-chip transistors, coupled with reductions in voltage levels, makes each generation of microprocessors increasingly vulnerable to transient faults. In a multithreaded environment, we can detect these faults by running two copies of the same program as separate threads, feeding them identical inputs, and comparing their outputs, a technique we call Redundant Multithreading (RMT).This paper studies RMT techniques in the context of both single- and dual-processor simultaneous multithreaded (SMT) single-chip devices. Using a detailed, commercial-grade, SMT processor design we uncover subtle RMT implementation complexities, and find that RMT can be a more significant burden for single-processor devices than prior studies indicate. However, a novel application of RMT techniques in a dual-processor device, which we term chip-level redundant threading (CRT), shows higher performance than lockstepping the two cores, especially on multithreaded workloads.
Philosophy as Training for Death: Reading the Ancient Christian Martyr Acts as Spiritual Exercises

In recent years several notable studies—including those by Judith Perkins, Daniel Boyarin, and Elizabeth Castelli—have assessed the importance of martyrdom and suffering in constructions of ancient Christian identity. This essay takes as its starting point the observation by Perkins that in early Christian communities, the threat of suffering (whether real or perceived) worked to create a particular kind of self. In Perkins's view, many ancient Christians came to believe that “to be a Christian was to suffer.” Christian martyr acts, when understood as textual vehicles for the construction of culture and the articulation of Christian identities, emerge as one mechanism by which such selves were constructed. In the pages that follow I will explore how the reading and hearing of narratives about martyrdom constituted an exercise derived from Greek philosophy, adapted to inspire a largely nonliterate audience. This exercise not only trained early Christians to be ready for death and the world to come, but also worked to shape their perceptions of the Christian way of life in this world.
Legal norms and practices affecting the mentally deficient.

Preliminary report of the findings of a three-year empirical study of the operation of both civil and criminal laws, in selected jurisdictions of the United States, affecting the mentally retarded and their families.
A frequency-domain mixer model for diffusion-cooled hot-electron bolometers

A new frequency domain hot-electron bolometer (HEB) mixer model is described, which takes into account the non-uniform temperature distribution found in superconducting diffusion-cooled devices. In this model the bolometer is discretized into a finite number of segments, and the non-linear large signal response to local oscillator and DC heating is found by an iterative algorithm. A frequency-domain coupling matrix is introduced to represent small-signal modulations around the large-signal values of temperatures and heat flows inside the device. The coupling matrix and a Norton representation of the mixer DC and intermediate frequency (IF) circuit allows the mixer conversion to be calculated.
Effect of histamine on the pulmonary circulation in dogs.

Histamine was administered to dogs by the intravenous route near the right atrium in doses of 9.6 to 19 γ/Kg. body weight. It produced a severe drop in systemic blood pressure, negligible changes in heart rate and respiration, usually a fall in cardiac output and no change in left atrial or pulmonary artery wedge pressure. The pulmonary artery pressure showed an initial rise and then a fall following the drop in systemic blood pressure. Pulmonary arteriolar resistance followed the changes in cardiac output. There appeared to be no consistent evidence of pulmonary vascular constriction following the injection of histamine in the doses used in this study.
Some Theoretical Rheological Characteristics of the Mechanical Signals in Sensory Evaluation of Texture

In sensory evaluation of mechanical properties, the gauged object and the tissues in contact (i.e. the hand, mouth, etc.) form a system that can be described by an in-line array of two models, the object's and the tissue's. The hypothetical rheological properties of such combined systems were studied qualitatively using simple phenomenological models with and without failure criteria. It is demonstrated that the mechanical stimulus reaching the human sensory system can be different in both kind and magnitude from the signal produced by testing machines irrespectively of the test geometry. It is also shown how the deformation rate can affect the rheological character of the stimulus and how damage to the sensory system (particularly the teeth) can occur if the deformation rate is not controlled.
Geological evidences of recent floods

In the present-day discussion of floods, flood-protection, and soil-erosion, the impression is very commonly given that there were no serious floods in America before the brief epoch of rapid spread of population, intensive cultivation, and large-scale stock-raising which have characterized the last decades of our history. Great stress is laid upon the fact that floods have been intensified by the destruction of the vegetative cover, by too intensive cultivation, by over-grazing, and by various other causes to which our people have been a party. But, when we examine the abundant record preserved at many places in our country and extending far, far back of the brief epoch of human occupation, the evidence is quite out of accord with this opinion.
Energy calibration of a linear accelerator with photonuclear reactions

Photonuclear reactions have been used to calibrate the energy of a Sagittaire clinical electron accelerator between 10 and 30 MeV. Thresholds at 10.8 MeV for the 63Cu(γ,n)62Cureaction and 29.7 MeV for the 32S(γ,3p)29Al reaction provided two energy points. The break in the 16O(γ,n)15O activation yield curve at 17.3 MeV was determined as an intermediate point. The relationship between electron kinetic energy and current through the energy‐analyzing magnet was found to be linear within 1.0% in this energy range.
Theory of the Alternating-Gradient Synchrotron

Abstract The equations of motion of the particles in a synchrotron in which the field gradient index n=−( r B ) ∂B ∂r varies along the equilibrium orbit are examined on the basis of the linear approximation. It is shown that if n alternates rapidly between large positive and large negative values, the stability of both radial and vertical oscillations can be greatly increased compared to conventional accelerators in which n is azimuthally constant and must lie between 0 and 1. Thus aperture requirements are reduced. For practical designs, the improvement is limited by the effects of constructional errors; these lead to resonance excitation of oscillations and consequent instability if 2νx or 2νz or νx + νz is integral, where νx and νz are the frequencies of horizontal and vertical betatron oscillations, measured in units of the frequency of revolution. The mechanism of phase stability is essentially the same as in a conventional synchrotron, but the radial amplitude of synchrotron oscillations is reduced substantially. Furthermore, at a “transition energy” E1 ≈ νxMc2 the stable and unstable equilibrium phases exchange roles, necessitating a jump in the phase of the radiofrequency accelerating voltage. Calculations indicate that the manner in which this jump is performed is not very critical.
Conservative management of broken guidewire: Case reports:

Fractures of coronary guidewires during percutaneous coronary intervention within a coronary vessel lumen are a rare but serious complication. There have been several cases reported in the literature, some managed with surgical intervention, others with medical therapy. We present two prospective cases from our center. Both cases were managed successfully with medical therapy.
Radiobiological Studies Using Synchrotron-produced Ultrasoft X-rays

Ultrasoft X-rays have been extensively used to explore radiobiological mechanisms surrounding cell killing. These studies for the most part have been linked to a small number of X-ray energies. Recently, this field of study has been broadened by the availability of synchrotron-produced ultrasoft X-rays which can be produced at any desired energy. We have taken advantage of the University of Wisconsin Synchrotron to reexamine two fundamental radiobiological questions: Dose RBE vary with different ultrasoft X-ray energies? Dose the fraction of the nuclear volume exposed to equal total X-ray energy modify cell cytotoxicity? The first study focuses on the survival of Chinese hamster V79 and mouse C3H10T1/2 cells irradiated with synchrotron-produced 273 eV and 860 eV ultrasoft X-rays. These two energies, which are available by multilayer monochromatization of the synchrotron output spectrum, exhibit equal attenuation within living cells. Such an isoattenuating energy pair allows the direct examination of how biological effectiveness varies with the energy of the ultrasoft X-rays. In comparing survival results, we find similar biological effectiveness of these two energies for both the C3H10T1/2 and the V79 cells. These results are no consistent with previous findings of increasing RBE with decreasing ultrasoft X-ray energies. In addition, after correcting for mean nuclear based on measurements of cell thickness obtained with confocal microscopy, we find no significant differences in survival between the two ultrasoft X-ray energies and 250 kVp X-rays. These results suggest that RBE does not increase with decreasing energy of ultrasoft X-ray between 860 eV and 273 eV. In a second study we introduced an method which allows partial-volume irradiation of live cells using synchrotron-produced ultrasoft X-rays and micro-fabricated irradiation masks. The masks were made by X-ray lithography at the University of Wisconsin Synchrotron Radiation Center, and they consist of 1.85-micron-wide stripes of gold 1.35 microns apart plated onto thin silicon nitrate membranes. When placed adjacent to mylar on which live cells are plated, these masks allow cells to be irradiated in a striped pattern with dimensions much smaller than the cell nuclei. Using 1340 eV synchrotron-produced X-rays, we compare the survival of cells subjected to uniform irradiation and cells subjected to partial-volume irradiation. Our results show that, at equal mean dose to the nucleus (i.e. equal total energies deposited), survival is not statistically different for the two treatments over a wide range of doses. Thus, imparting equal energies to smaller intranuclear volumes does not appear to modulate cell killing.
Case-based reasoning as a methodology for accumulating human expertise for discrete system control

This paper discusses the use of case-based reasoning in the control of increasingly automated systems Case-based reasoning is proposed as a basis to support recognition-primed decision making by system operators. A conceptual architecture that uses case-based reasoning as a source of control expertise is offered to support operations planning and automatic control.
Estimating the Location and Orientation of Complex, Correlated Neural Activity using MEG

The synchronous brain activity measured via MEG (or EEG) can be interpreted as arising from a collection (possibly large) of current dipoles or sources located throughout the cortex. Estimating the number, location, and orientation of these sources remains a challenging task, one that is significantly compounded by the effects of source correlations and the presence of interference from spontaneous brain activity, sensor noise, and other artifacts. This paper derives an empirical Bayesian method for addressing each of these issues in a principled fashion. The resulting algorithm guarantees descent of a cost function uniquely designed to handle unknown orientations and arbitrary correlations. Robust interference suppression is also easily incorporated. In a restricted setting, the proposed method is shown to have theoretically zero bias estimating both the location and orientation of multi-component dipoles even in the presence of correlations, unlike a variety of existing Bayesian localization methods or common signal processing techniques such as beamforming and sLORETA. Empirical results on both simulated and real data sets verify the efficacy of this approach.
In Vitro Expression of Immunoglobulin M and G Subclasses by Murine B Lymphocytes in Response to a Polyclonal Activator from Actinomyces

A cell wall extract from the gram-positive bacterium Actinomyces viscosus contains the mitogen AVIS, a potent polyclonal B-cell activator for murine B lymphocytes. Cultures of splenocytes from heterozygous nude mice in the presence of an optimal concentration of AVIS responded by a deoxyribonucleic acid synthesis response, and proliferaction reached maximal levels after 3 to 4 days. There was no requirement for T cells in the deoxyribonucleic acid synthesis, proliferactive, immunoglobulin M (IgM), or IgG responses. Significant numbers of IgM-producing cells were present as early as day 2 of culture, whereas later in the culture periods (days 3 to 6) IgG-producing plasmablasts and plasma cell were observed. In cultures of splenocytes from nude mice stimulated with AVIS for 4 to 5 days, 20 to 25% of the recoverable cells synthesized IgM, and 10% contained only IgG2 or IgG3; 5 to 8% of the cells stained for both IgM and IgG2 or both IgM and IgG3. Fine-structure analysis of AVIS-stimulated splenocytes from heterozygous nude mice after 3 days of culture demonstrated that 20 to 25% of the cells were activated to various degrees. Of most importance, all of the activated cells had the characteristic of B lymphoblasts, plasmablasts, or plasma cells. This is the first demonstration of a polyclonal B-cell activator other than lipopolysaccharide which induces IgG3 synthesis. We suggest that AVIS may be a useful probe for the exploration of the functional activities of subpopulations of B cells.
Biological parametric mapping accounting for random regressors with regression calibration and model II regression.

article i nfo Article history: Accepted 8 May 2012 Available online 15 May 2012 Massively univariate regression and inference in the form of statistical parametric mapping have transformed the way in which multi-dimensional imaging data are studied. In functional and structural neuroimaging, the defactostandard "designmatrix"-basedgeneral linearregression model and its multi-level cousins haveenabled investigation of the biological basis of the human brain. With modern study designs, it is possible to acquire multi-modalthree-dimensionalassessmentsofthe sameindividuals—e.g.,structural,functionalandquantitative magneticresonanceimaging,alongside functionaland ligand binding mapswithpositron emission tomography. Largely, current statistical methods in the imaging community assume that the regressors are non-random. For morerealisticmulti-parametricassessment (e.g.,voxel-wise modeling),distributionalconsideration ofall obser- vations is appropriate. Herein, we discuss two unified regression and inference approaches, model II regression and regression calibration, for use in massively univariate inference with imaging data. These methods use the design matrix paradigm and account for both random and non-random imaging regressors. We characterize thesemethodsinsimulationandillustratetheiruseonanempiricaldataset.Bothmethodshavebeenmaderead- ily available as a toolbox plug-in for the SPM software.
A critical review of simulation-based medical education research: 2003-2009

Objectives This article reviews and critically evaluates historical and contemporary research on simulation-based medical education (SBME). It also presents and discusses 12 features and best practices of SBME that teachers should know in order to use medical simulation technology to maximum educational benefit. Methods This qualitative synthesis of SBME research and scholarship was carried out in two stages. Firstly, we summarised the results of three SBME research reviews covering the years 1969–2003. Secondly, we performed a selective, critical review of SBME research and scholarship published during 2003–2009. Results The historical and contemporary research synthesis is reported to inform the medical education community about 12 features and best practices of SBME: (i) feedback; (ii) deliberate practice; (iii) curriculum integration; (iv) outcome measurement; (v) simulation fidelity; (vi) skill acquisition and maintenance; (vii) mastery learning; (viii) transfer to practice; (ix) team training; (x) high-stakes testing; (xi) instructor training, and (xii) educational and professional context. Each of these is discussed in the light of available evidence. The scientific quality of contemporary SBME research is much improved compared with the historical record. Conclusions Development of and research into SBME have grown and matured over the past 40 years on substantive and methodological grounds. We believe the impact and educational utility of SBME are likely to increase in the future. More thematic programmes of research are needed. Simulation-based medical education is a complex service intervention that needs to be planned and practised with attention to organisational contexts. Medical Education 2010: 44: 50–63