cssi/SciSciGPT-SciSciNet huggingface dataset:
THE STRUCTURAL SYNTHESIS CONCEPT AND ITS POTENTIAL ROLE IN DESIGN WITH COMPOSITES

The use of composite materials in the design of structural systems offers the designer a wide range of new degrees of freedom. With this increase in the number of alternative choices available to the structural engineer comes the responsibility for providing a rational basis for seeking optimum designs. The structural synthesis concept is reviewed as a framework within which the quantifiable portion of the design process can be formulated. A concise statement of a rather general class of structural synthesis problems is recognized as a nonlinear mathematical programming problem. The essential ideas involved in sequential solution methods are illustrated by outlining a feasible directions solution method. It is pointed out that alternative formulations are possible in which the usual statement, as an inequality constrained minimization problem, is transformed into a sequence of unconstrained minimization problems. Extension of the structural synthesis approach to fiber composite structural systems is illustrated in terms of an idealized example. The example problem is a simply supported, rectangular, multi-layer, resin-matrix, fiber composite plate subject to a multiplicity of inplane load conditions. The failure modes considered include gross plate buckling, combined stress failure in a layer and delamination. The objective function is taken as cost of fiber material per unit surface area of plate. Finally, in discussing the potential role of structural synthesis in the design of composite material structural systems some problem areas are identified.
A New Converter Topology for Switched Reluctance Machines to Improve High-Speed Performance

In this paper, a new converter topology for high speed Switched Reluctance Machine drives is investigated. This new topology helps excitation current built up sufficiently and demagnetize quickly by having an auxiliary energy storage element connected directly to switches. Phase windings can be excited faster by the additional energy storage unit with high voltages. Similarly, phase current can be decreased rapidly during the recharging of this unit. Additionally, upper switches are added in the replacement of common switch to regulate the auxiliary port. These switches enable the phases to work independently. Therefore, it is easier to construct the control algorithms by using this flexibility. The SRM, converter and the control algorithm is simulated using an SRM model based on the Finite Element Analysis. The performance of the proposed topology is verified at various operating conditions using this simulation platform.
Study on Dynamic Change of In Situ Resistance During Sintering Process of YBCO Precursor Film

YBa2Cu3O7-x precursor film prepared by metal-organic deposition method was sintered and oxygenated at 800 °C and 450 °C, respectively. The dynamic in situ resistance data in the sintering process of film was recorded, and the phase composition and transformation of YBa2Cu3O7-x precursor film in treating stages were discussed. In the heating stage of 710–795 °C, the film resistance increased with temperature, which may be explained by that the grains grew larger and internal gaps formed. The tetragonal YBa2Cu3O7-x shows good conductivity at 77–270 K. When temperature ranged from 450 to 800 °C, the tetragonal YBa2Cu3O7-x became very sensitive to oxygen, and the film resistance dropped sharply once oxygen entered. The scanning electron microscope images showed that the oxygen infiltration at 800 °C was more contributing to grain fusion and connectivity. The X-ray diffraction patterns of samples with oxygen infiltration at 800 °C exhibited that the phase transformation to YBa2Cu3O7-x was more fully. The R-T curve and I-V curve were measured by the four-probe method, the transition temperature Tc are 89.8 K and 93.4 K, and the critical current densities Jc are 0.32MA/cm2 and 0.89MA/cm2 (77 K, 0 T) respectively. Tc and Jc curves illustrated that the samples had higher superconductivity, compared with those experienced oxygen infiltrations at 450 °C.
Role of Drosophila Rap/Fzr (DCdh1) in Retinal Axon Targeting and its Interactions with Loco and Liprin-alpha

The development of the wild type Drosophila compound eye involves stereotypical targeting of photoreceptor axons to the specific layers of the optic ganglion, medulla and lamina, in the third instar larvae. To test the hypothesis that ubiquitin ligases play an important role during retinal axon targeting we have examined the patterns of axon targeting in the developing eye of the retina aberrant in pattern (rap/fzr) mutants. Rap/Fzr is a homolog of mammalian Cdh1, an activator of anaphase promoting complex (APC), a multi-subunit E3 ubiquitin ligase, regulating the cell cycle progression. Previous work has shown that Rap/Fzr is required during eye development for proper cell cycle regulation, glia differentiation and pattern formation. It was also necessary for proper neuromuscular junction development and circadian rhythms. Our results show that Rap/Fzr is required for proper retinal axon targeting in the developing eye. Using ro-tau-lacZ, we show that the R2-R5 axons fail to stop in the lamina and mis-target to the medulla levels. Also, mosaic analyses experiments using FLP-FRT and GAL4-UAS techniques show that Rap/Fzr functions in a cell autonomous manner. To test for possible role of other signalling molecules and interactions with Rap/Fzr, we have examined rap/fzr axon projection phenotypes in double mutant combinations with the RGS protein, locomotion defective (loco) mutants and a scaffolding protein, Liprin-. Our studies suggest that Rap/Fzr is required for proper axon targeting during Drosophila visual system development, and the phenotype is enhanced in double mutants with either loco or Liprin-. These results are consistent with other mammalian studies reporting a role of Cdh1 in axon growth and targeting and provides further insights into neuronal functions of the ubiquitin ligase APC/CCdh1. HighlightsO_LILoss of rap/fzr in the third instar Drosophila eye disc leads to photoreceptor axon overgrowth C_LIO_LIOverexpression of rap/fzr leads to photoreceptor axon leads to axon shortening and clumping C_LIO_LILoss of LocoP452 leads to photoreceptor overgrowth C_LIO_LIDouble mutants of rap and loco or rap and Liprin- show axon enhancement of the axon targeting defects in the Drosophila third instar larvae eye imaginal discs. C_LI
Stability and changes in problem behavior during adolescence: multilevel predictors and moderators

This study predicted that community ethnic heterogeneity (controlling for community poverty), family adversity (i.e., family economic hardship and non-intact twoparent family/single parenthood), family social resources (i.e., parent-adolescent relationship, parental control, parental warmth, parental knowledge), and individual traits (i.e., racial minority status and gender) would influence adolescent problem behavior trajectories both additively and multiplicatively. In addition, the study predicted that there would be racial/ethnic and gender differences in problem behavior over time. An effective analysis of community influence on individual outcomes requires a multilevel analysis that includes community-level, family-level, and individual-level variables. This multilevel analysis used 15,170 adolescent data values from the National Longitudinal Study of Adolescent Health, Wave 1 (1995), Wave 2 (1996), Wave 3 (2001), and the 1990 U.S. Census. The findings demonstrate that there is: (a) change in adolescent problem behavior over time; (b) unique influences of family adversity, family social resources, and individual factors (i.e., race and gender) on adolescent problem behavior; (c) diminishing effects of community poverty over time; (d) diminishing effects of family social resources (i.e., family warmth and parentadolescent relationship) producing stability and equality over time during late adolescence; and (c) contextual dissipation of the influences of some family social resources (i.e., parentadolescent relationship) under high ethnic heterogeneous conditions. .
How to be Resilient? Local Philanthropy as a Collective Response to Natural Disasters

When communities are struck by natural disasters, human service organizations play an important role in supplementing governmental aids and catering to immediate humanitarian needs. Social capital is one of many factors affecting resource mobilization directed toward human service organizations as a proxy for local philanthropy. This study analyzed the effect of social capital on local philanthropy in communities affected by natural disasters and compared it to the effect of corporate philanthropy. In addition, this study examined how the relationships among social capital, corporate philanthropy, and local philanthropy were moderated by racial diversity to answer a long-standing argument regarding the effect of racial diversity on philanthropy. To this end, a panel dataset covering three given years and 3121 US counties was analyzed using GEE models. The results suggest that social capital does not always facilitate local philanthropy and its influence on local philanthropy is catalyzed by racial diversity. Also, corporate philanthropy positively influences resource mobilization toward human service organizations, more noticeably in communities affected by natural disasters.
Automatic Fully-Contextualized Recommendation Extraction from Radiology Reports.

Recommendations are a key component of radiology reports. Automatic extraction of recommendations would facilitate tasks such as recommendation tracking, quality improvement, and large-scale descriptive studies. Existing report-parsing systems are frequently limited to recommendations for follow-up imaging studies, operate at the sentence or document level rather than the individual recommendation level, and do not extract important contextualizing information. We present a neural network architecture capable of extracting fully contextualized recommendations from any type of radiology report. We identified six major “questions” necessary to capture the majority of context associated with a recommendation: recommendation, time period, reason, conditionality, strength, and negation. We developed a unified task representation by allowing questions to refer to answers to other questions. Our representation allows for a single system to perform named entity recognition (NER) and classification tasks. We annotated 2272 radiology reports from all specialties, imaging modalities, and multiple hospitals across our institution. We evaluated the performance of a long short-term memory (LSTM) architecture on the six-question task. The single-task LSTM model achieves a token-level performance of 89.2% at recommendation extraction, and token-level performances between 85 and 95% F1 on extracting modifying features. Our model extracts all types of recommendations, including follow-up imaging, tissue biopsies, and clinical correlation, and can operate in real time. It is feasible to extract complete contextualized recommendations of all types from arbitrary radiology reports. The approach is likely generalizable to other clinical entities referenced in radiology reports, such as radiologic findings or diagnoses.
Electrically Conductive and Protective Coating Reaction with LSCF Material

Ferritic stainless-steel interconnect materials are used in intermediate or high-temperature SOFCs because of their oxidation resistance, high formability, and low cost. Their corrosion resistance is due to the formation of a protective chromium oxide scale during operation. However, the protective oxide layer produces Cr-containing volatile species at SOFC operating temperatures and conditions, which can cause cathode poisoning. Spinel coatings have been developed to prevent cathode poisoning while maintaining an electrically conductive pathway through SOFC stacks. Generally, Mn-Co-O spinel has been the material of choice, but PNNL has developed an Mn-Cu-O spinel protective coating to remove the costly Co and enhance the electrical conductivity. This paper will focus on the electrically conductive coating's compatibility with LSCF in high-temperature operating environments.
Reviewing Racial Microaggressions Research: Documenting Targets' Experiences, Harmful Sequelae, and Resistance Strategies.

In this article, we review the theoretical and empirical literature on racial microaggressions from 2007 to 2020 (N = 138 articles). First, we refine racial microaggressions theory and update the d...
The Young Derrida and French Philosophy, 1945–1968: L’ambiguité du concours

In the last chapter we tracked the changes in Derrida's thought during the middle years of the 1960s, showing how it mutated from a post-existentialist reading of phenomenology into a quasi-structuralist theory. But the causes and stakes of this transformation remain unexplained. Over the next two chapters, I intend to examine this change from two perspectives: the move away from phenomenology, and the confrontation with structuralism. The latter will shed light on the political meaning of Derrida's project and provide new ways to understand the role played by antihumanism in French theory. The former is worthy of consideration, because it concerns the rise of deconstruction as a methodology, the genesis of an aspect of Derrida's work that has been central to its reception into the English-speaking world. For, while before 1964 Derrida focused his attention almost exclusively on Husserl's texts and participated in the technical realm of French phenomenological discourse, after 1964 the vast majority of his books and articles examined texts from outside of the phenomenological canon. The key to this unprecedented expansion in Derrida's professional interests lies, as I will argue, in his new teaching responsibilities. While Merleau-Ponty opened phenomenology up to the human sciences, by urging the philosopher to place himself at “school of facts,” Derrida widened his intellectual horizons by returning to the ENS, Rue d’Ulm. Scholars have been resistant to placing Derrida's thought within its institutional context, because his autobiographical statements seem to refuse such an analysis: the philosopher of the marginal, Derrida enjoyed his contested position on the fringes of academic philosophy. In a 1976 article, Derrida asserted that, it had been obvious that the work in which I was involved…– the (affirmative) deconstruction of phallogocentrism as philosophy – did not belong simply to the forms of the philosophical institution…It did not proceed according to the established norms of theoretical activity. In more than one of its traits and in strategically defined moments, it had to have recourse to a “style” unacceptable to a university reading body (the “allergic” reactions to it were not long in coming). Further, Derrida was careful to assert the “dissociation” between his published and teaching work, separating his philosophical project, which left no structure unquestioned, from his teaching role where he had to follow the norms of a jury and a canon “that in his eyes [had] been discredited.”
SHEAR MODULUS AND DAMPING IN SOILS: DESIGN EQUATIONS AND CURVES

Equations and graphs for the determination of shear modulus and damping of soils, for use in design problems involving repeated loading or vibration of soils, are presented. These equations and graphs are based on numerous laboratory tests on both remolded and undisturbed cohesive soils and on clean sands. Comparison of the measured and computed values shows good agreement. An example problem showing how these equations and curves are used is given.
Aging of membrane transport mechanisms in the central nervous system: GABA transport in rat cortical synaptosomes

Abstract A kinetic study of sodium dependent GABA transport has been made in synaptosomes from 30-month old Long-Evans rats and compared to results from 2-month old animals. Initial velocity of uptake was measured as a function of both sodium and GABA concentration, and these data were then fitted to the model which was found to give best fit for the 2-month data. An excellent fit was also obtained for the 30-month data. Thus there has been no change with age in the fundamental mechanism by which carrier, sodium, and GABA interact in the process of transport. However, quantitative changes were found to occur with age both in initial velocity of uptake and in those constants which quantitate the model. The rate equation for the model was utilized along with the best fit constants to define and calculate certain parameters which were then used to quantitatively compare the transport mechanism in young and aged animals.
Runtime constraint checking approaches for OCL, a critical comparison

There are many benefits of checking design constraints at runtime—for example, automatic detection of design drift or corrosion. However, there is no comparative analysis of different approaches although such an analysis could provide a sound basis for determining the appropriateness of one approach over the others. In this paper we conduct a comparative analysis and evaluation of different constraint checking approaches possible for the Object Constraint Language (OCL). We compare several approaches including (1) direct translation to implementation languages, (2) use of executable assertion languages, and (3) use of aspect-oriented programming languages. Our comparison includes both quantitative metrics such as runtime performance and qualitative metrics such as maintainability of constraint checking code. We found that the implementation language-based approaches perform better in terms of memory footprint and runtime overheads but the other approaches are more appealing in terms of maintainability. Keywords-pre and postconditions; runtime constraint checking; AspectJ; JML; OCL
Multibeam Sonar Performance Analysis Value and Use of Statistical Techniques

The Naval Oceanographic Office uses quantitative methods employing statistical measurements to analyze and evaluate the performance and behavior of multibeam sonar bathymetry systems. Datasets are made that determine the residual differences between a reference surface and multibeam sounding files as a function of beam angle. The resultant beam-wise analysis facilitates artifact detection, trends, overall uncertainty, dataset limitations, and system performance compliance against specifications or other special requirements. The technique used is presented with examples of its application in analyzing system performance, data processing, and survey planning in two actual case studies.
Continuous curve matching with scale-space curvature and extrema-based scale selection

We extend a symmetric parametric curve matching algorithm designed for recognition and morphometry by incorporating Gaussian smoothing and curvature scale-space. A general statement of the matching theory and the properties of the associated algorithm is given. Gaussian smoothing is used to assist in approximating the continuous solution from the discrete solution given by dynamic programming. The method is then investigated in a multi-scale framework, which has the advantage of reducing the effects of noise and occlusion. A novel scale-space derived energy functional that incorporates geometric information from many scales at once is proposed. The related issue of selecting a smoothing kernel for a given matching problem is also explored, resulting in a topologically based method of scale-selection. This application requires estimating the matching between the fine and coarse scale versions of the same curve. We provide a tool for finding this inter-scale, intra-curve correspondence, based on tracking curvature extrema through scales. These novel algorithms are demonstrated on both 2D and 3D data.
A tribute to Zakariya Razi (865 - 925 AD), an Iranian pioneer scholar.

The resurgence of Islamic Civilization in the Near East in the 7 th century AD and its expansion to Persian Empire and Westward provided opportunities of access Persian, Hellenic, and Roman writings in philosophy and medicine. Based on their observations and experiences, Islamic physician-philosophers expanded upon those writings and at times challenged them. Among these physician-philosophers admiring and challenging Galen was Zakariya Razi described as the greatest physician of Islam and Medieval Ages. A search of electronic and written materials
Comprehensive Freight Demand Data Collection Framework for Large Urban Areas

The chapter analyses characteristics and unique features of the freight system, data requirements of different modeling techniques, and the roles of various data collection procedures. The analyses produce a set of findings of relevance to the design of comprehensive freight data collection frameworks for mid-size and large urban areas. Building on these findings, the chapter identifies a modular data collection framework that would enable transportation agencies to mix and match data collection efforts depending on their needs and constraints.
Breast-Related CSF Shunt Complications: Literature Review with Illustrative Case

In this article, we discuss and classify breast-related ventriculoperitoneal (VP) cerebrospinal fluid (CSF) shunt complications, and provide a literature review. Shunt complications related to pre-existing breast implants comprise nearly half of the breast-related shunt complications reported thus far. We present a complication of shunt failure in a 61-year-old woman who had previously undergone mastectomies for breast cancer with implant reconstruction. Following shunting, she developed headaches, fever, and right-sided breast swelling and erythma consequent to breast implant rupture, distal shunt migration, and CSF pseudocyst. This case is unique in that it involved rupture of a breast implant from VP shunt insertion. For complication avoidance, neurosurgeons should be aware of the potential pitfalls in shunting patients with breast implants.
Intracameral Muramyl Dipeptide-Induced Paracellular Permeability Associated with Decreased Glutamate Transporter and g -Glutamyltranspeptidase Activities

Muramyl dipeptide (MDP) (N -acetylmuramyl- L -alanyl- D - isoglutamine) was injected intracamerally to test if MDP applied to the aqueous side of the blood-aqueous barrier would increase paracellular permeability in association with diminished uptake of glutamate. The symptoms of anterior uveitis, i.e., increase in vascular dilatation, could be detected as early as 30 min post MDP injection while aqueous protein concentration did not increase at this time suggesting an initial dissociation between the circulatory and epithelial barrier responses. However, at 45 min, the aqueous protein concentration increased 10-fold (201+/-174 to 2094+/-1835 micrograms ml-1;P<0.001) rising progressively to 20-fold above the control eye at 60 min post injection (254+/-194 vs. 5038+/-2514 micrograms ml-1;P<0.001). Epithelial cell barrier paracellular permeability increased at 45 min as evidenced by the enhanced efflux of radiolabelled L -glucose out of the aqueous (8% and 13% faster than control at 45 and 60 min post MDP injection, respectively), coinciding with the accelerated protein influx. A near 50% reduction in efflux of both radiolabelled glutamate and D -aspartate was consistent with reduced glutamate uptake by the transport system X-AG. In addition, a 24% decline in aqueous glutamate, but not aspartate, was detected in the aqueous of the MDP-treated eyes in association with a 54% decrease in iris/ciliary body gamma-glutamyltranspeptidase activity consistent with reduced de novo glutamate formation from glutamine. The aqueous of MDP injected eyes also had 6-fold and 34-fold higher prostaglandin E2and F2alphaconcentrations, respectively (P</=0.03) as well as reduced AH bicarbonate concentration. These results suggest that increased paracellular permeability is associated with diminished gamma-glutamyltranspepidase-mediated glutamate production, X-AGtransport activity, and cellular acidosis in the MDP-induced prostaglandin-mediated inflammation.
Abstract A83: Organophosphate pesticides and sex steroid hormones in NHANES III

Abstracts: Frontiers in Cancer Prevention Research 2008 A83 Background Organophosphate pesticides (OP) may perturb hormone balance, and thus may affect men’s health, e.g., prostate cancer. We evaluated whether men from the general population with higher urinary OP metabolites had higher or lower concentrations of sex steroid hormones than men with lower levels. Methods Concentrations of 3,5,6-trichloro-2-pyridinol (TCPY), a chlorpyrifos metabolite, and 4-nitrophenol (4-NP), a methyl parathion metabolite, previously were measured in spot urine for 1,338 men ages 20-59 who participated in the Third National Health and Nutrition Examination Survey (NHANES III). We measured serum concentrations of testosterone, estradiol, and sex hormone binding globulin (SHBG) for 1,637 men ≥ 12 years old who participated in the morning session of Phase I of NHANES III. 189 men participated in both sub-studies, forming the study population. Linear regression was used to estimate geometric mean hormone concentration by binary category of creatinine-corrected urinary OP concentration adjusting for age, US region, smoking, race, education, body mass index, and physical activity. We tested for trend across quartiles of TCPY and across 3 categories (< limit of detection (LOD), 2 categories ≥ LOD) of 4-NP by entering a single ordinal term in the model with values at the category medians, the coefficient for which was evaluated by the Wald test. Results Mean testosterone (95% confidence interval) was significantly higher in men with higher TCPY (≥ median: 5.55 (4.95, 6.22)) compared with lower ( 0.10). Conclusion This cross-sectional study, the first in a general population of US adult men, suggests positive associations of chlorpyrifos with testosterone, estradiol, SHBG, and inverse associations of methyl parathion with testosterone and estradiol. These findings differ somewhat from those in occupationally-exposed groups. Given that a) our findings are compatible with the hypothesis that OPs influence hormones even at low exposure, b) OPs were available to consumers and commonly used, and c) a prior study observed a higher prostate cancer risk in commercial applicators who used an OP and had a family history of prostate cancer (Am J Epidemiol 2003;157:800-14), future studies are warranted on OPs and men’s health, including prostate cancer. Funding: Maryland Cigarette Restitution Fund at Johns Hopkins Citation Information: Cancer Prev Res 2008;1(7 Suppl):A83.
Identification of c-myc as a Down-stream Target for Pituitary Tumor-transforming Gene

Pituitary tumor-transforming gene (PTTG) encodes a protein implicated in cellular transformation and transcriptional regulation. To identify downstream target genes, I established cell lines with tightly regulated inducible expression of PTTG. DNA arrays were used to analyze gene expression profiles after PTTG induction. I identified c-myc oncogene as a major PTTGtarget. Induction of PTTG resulted in increased cell proliferation through activation of c-myc. I showed that PTTG activates c-myc transcription in transfected cells. PTTG binds to c-myc promoter near the transcription initiation site in a protein complex containing the upstream stimulatory factor (USF1). I have defined the PTTG DNA-binding site and mapped PTTG DNA binding domain to a region between amino acids 61 and 118. Furthermore, I demonstrated that PTTG DNA binding is required for its transcriptional activation function. These results definitively established the role of PTTG as a transcription activator and indicate that PTTG is involved in cellular transformation and tumorigenesis through activation of c-myc oncogene.
Naturally occurring arteriosclerosis in nonhuman primates

Summary (1) Arteriosclerotic lesions are described and illustrated in the coronary arteries and in the thoracic and abdominal segments of aortas in the majority of the members of 17 families of primates (a total of 67 primates were studied). (2) The arteriosclerotic process seemed to be initiated by degeneration of the internal elastic membrane, or in the case of the thoracic aorta, of the innermost medial elastic tissue. This was associated with intimal accumulations of mucopoly-saccharide, followed by intimal proliferation of fibroblasts and smooth muscle cells, and by development of intimal connective tissue fibrils. (3) Extreme variability was observed in the amounts of lipids deposited in intimas with the same degree of thickening, from mild to severe. Pronounced intimal thickening in some cases showed little or no lipid involvement. (4) Continuing intimal lipid infiltration in some primates seemed responsible for the eventual mobilization of macrophages and deposition of cholesterol crystals in the intima — and hence eventually for the development of the mature, athero-matous plaques closely resembling those seen in the human being. (5) The pathogenesis of naturally occurring arteriosclerosis in primates differs significantly from that induced in them by feeding cholesterol. The initial degenera-tive intimal process in the naturally occurring disease appears clearly primary , and seems neither associated with nor caused by lipid deposition in the intimal layer.
Vowel insertion in Scottish Gaelic

Scottish Gaelic has been cited as providing an instance of vowel excrescence (Hall 2006). One of the defining properties of excrescent vowels is that they are phonologically inert and are not motivated by – nor do they contribute to – the syllable structure of a language. In this paper, we report on a series of experiments which tap into native speakers' intuitions of syllable structure in Scottish Gaelic. Insofar as intuitions about syllable count and syllabification reflect phonological structure, our results suggest that the relevant vowels of Scottish Gaelic are not phonologically inert, and contribute directly to native speaker intuitions involving the number of syllables and the affiliation of consonants to those syllables. However, our results also establish that the relevant vowels have an intermediate phonological status, which also distinguishes them from underlying vowels.
Exploring the lack of dialogue in computer-supported collaborative learning

Research in collaborative learning has supported the hypothesis that dialogue between peers and between peers and teachers facilitates learning by the participants in the dialogue. Examples of these dialogues show dozens of turns (individual utterances by participants) in a single learning session. In contrast, measurements of interaction from computer-supported collaborative learning environments show that on-line dialogue looks much different, with an average of approximately one posting or less per student per week. Measurements of learning in these environments do suggest learning is occurring, but presumably, not based on the same kind of dialogue described in research on face-to-face collaboration. We explore explanations for how the learning is arising in CSCL environments based on the Vicarious Learning Project (Lee, Dineen, McKendree, & Mayes, 1999; McKendree, Stenning, Mayes, Lee, & Cox, 1998), but in the course of this explanation, two additional hypotheses emerge. We believe that some of the learning in CSCL environments occurs from the observation of the dialogue, the reflection induced by the potential of submitting, and in the interaction between the face-to-face and on-line environments.
Intersubband scattering as a tool to study the symmetry properties of a parabolic quantum well

Abstract The electron mobility in parabolic quantum wells is measured as a function of carrier density at low temperatures. The curves display pronounced maxima that indicate the onset of intersubband scattering, i.e. the population of another subband. We find that the population of a given subband only depends on the total carrier density almost independent of the position of the wavefuntion within the well which can be tuned via a front and back gate electrode. This is in agreement with predictions for a perfect parabolic potential. If a potential spike is inserted in the center of the PQW we find a complicated behavior for the mobility versus carrier density maxima which reflects the changed symmetry of the potential.
Design of Totally Fault Locatable Combinational Networks

The design of combinational logic networks is considered in which equivalent or indistinguishable stuck-type faults are confined to a small region of the network. A general type of fault equivalence called S-equivalence is introduced, which defines fault equivalence with respect to an arbitrary set of modules S. A network N is called totally fault locatable with respect to module set S, denoted TFLS, if all specified faults in N are S-equivalent. Some general structural properties of TFLS networks are derived. The problem of designing TFLS networks is investigated for S = {AND, OR, NAND, NOR, NOT} denoted AON, and S = {AON, EXCLUSIVE- OR} denoted AONE. All equivalent fault classes in TFLAON and TFLAONE networks can be identified by inspection. It is shown that every function has a TFLAONE network, that is, a realization where all equivalence classes can be identified by inspection, containing at most one control point or extra input. A method for constructing a TFLAONE realization of an arbitrary function is presented using at most one control point.
SOME FACTORS INFLUENCING THE PRODUCTION OF DIMETHYLAMINE AND FORMALDEHYDE IN MINCED AND INTACT RED HAKE MUSCLE

Mincing stimulated the breakdown of trimethylamine oxide (TMAO) to dimethylamine (DMA) and formaldehyde (HCHO) in red hake muscle at both above and below freezing temperatures. Aging of red hake muscle on ice as fillets (skin on or off) prior to frozen storage resulted in a greater extent of DMA production as compared to fillets derived from fish aged in the whole or gutted form. Frozen storage temperature influenced the extent of DMA production, yet the freezing nadir had no effect on the rate of its formation during storage at -5°C. Additive studies indicated that reducing conditions in the tissue exert considerable influence on the reaction rate in frozen minced tissue. Trimethylamine (TMA), DMA, dimethylaniline and citrate were found to inhibit the reaction in frozen minced tissue.
Social Physique Anxiety in Early Adolescent Black Females1

Abstract An adapted version of the 9-item Social Physique Anxiety Scale (SPAS) was administered to Black females (N = 179) ages 11 to 14 years. Comparison between body composition (BMI) and social physique anxiety (SPA) indicated greatest SPA in overweight/obese participants. No change over age was observed. In comparison to previous data for a White sample, these Black early adolescent females evidenced somewhat lower social physique anxiety than the White females. The lower SPA supports the hypothesis that Black females are more accepting of a larger physique in early adolescence. Factor analysis supported a substantitive/non-substantitive two-factor model for the SPAS-C.
Cloning, analysis, and chromosomal localization of myoxin (MYH12), the human homologue to the mouse dilute gene.

The mouse dilute gene encodes a novel type of non-muscle myosin that structurally combines elements from both nonmuscle myosin type I and nonmuscle myosin type II. Phenotypically, mutations in the mouse dilute gene result not only in the lightening of coat color, but also in the onset of severe neurological defects shortly after birth. This may indicate that the mouse dilute gene is important in maintaining the normal neuronal function in the mouse. The authors report the isolation and sequencing of [open quotes]myoxin[close quotes] (MYH12), the human homologue of the mouse dilute gene, and its assignment to human chromosome 15. 35 refs., 6 figs.
Detection of Escherichia coli O157:H7 using immunomagnetic separation and absorbance measurement

Abstract An assay system for detection of Escherichia coli O157:H7 was developed based on immunomagnetic separation of the target pathogen from samples and absorbance measurement of p-nitrophenol at 400 nm from p-nitrophenyl phosphate hydrolysis by alkaline phosphatase (EC 3.1.3.1) on the “sandwich” structure complexes (antibodies coated onto micromagnetic beads—E. coli O157:H7-antibodies conjugated with the enzyme) formed on the microbead surface. The effects of immunoreaction time, phosphate buffer concentration, pH and temperature on the immunomagnetic separation of E. coli O157:H7 from samples were determined and the conditions used for the separation were 1-h reaction time, 1.0×10−2 M PBS, pH 8.0 and 33 °C in this system. The effects of MgCl2 concentration, Tris buffer concentration, pH and temperature on the activity of alkaline phosphatase conjugated on the immuno-“sandwich” structure complexes were investigated after immunomagnetic separation of the target pathogen and the conditions used for the enzymatic amplification were 1.0×10−4 M MgCl2, 1.0 M Tris buffer, pH 8.0, 28 °C and 30-min reaction time during the assay. The selectivity of the system was examined and no interference from the other pathogens including Salmonella typhimurium, Campylobacter jejuni and Listeria monocytogenes was observed. Its working range was from 3.2×102 to 3.2×104 CFU/ml, and the relative standard deviation was 2.5–9.9%. The total detection time was less than 2 h.
The ethics of truth-telling and the problem of risk

Risk communication poses a challenge to ordinary norms of truth-telling because it can easily mislead. Analyzing this challenge in terms of a systematic divergence between expertise and public attitudes fails to recognize how two specific features of the concept of risk play a role in managing daily affairs. First, evaluating risk always incorporates an estimate of the reliability of information. Since risk communication is an effort at providing information, audiences will naturally and appropriately incorporate their assessment of the reliability of the risk communicator into their assessment of the risk as such. Second, one conceptual and grammatical feature of the concept of risk is to categorize experience as non-routine and demanding further deliberation. That is, the whole point of calling something a risk can be to distinguish it from activities or phenomena that need no further attention. Risk communications that stress relative comparisons of measured probabilities and expected utilities can be inconsistent with both features of our concept of risk. At best they mislead; at worst they undermine our society’s capacity to cope with risk. While there are no simple answers to these two conundrums, technical experts should bear them in mind when communicating with the broader public.
The reaction between ferrous polyaminocarboxylate complexes and hydrogen peroxide: An investigation of the reaction intermediates by stopped flow spectrophotometry

The reactions of Fe(II)EDTA, Fe(II)DTPA, and Fe(II)HEDTA with hydrogen peroxide near neutral pH have been investigated. All these reactions have been assumed to proceed through an active intermediate, I1, (Formula: see text) where pac is one of the three polyaminocarboxylates mentioned above. I1, whether .OH radical or an iron complex, reacts with ethanol, formate, and other scavengers at rates relative to k2 that, with the exception of t-butanol and benzoate, are similar, but not identical, to those expected for the.OH radical. In contrast, at pH 3, in the absence of ligands the reaction of I1 with Fe2+ was inhibited by ethanol and t-butanol and the reactivity of I1 towards these two scavengers relative to ferrous ion is identical to that exhibited by the hydroxyl radical. When pac = HEDTA, the intermediate of the first reaction reacts with formate ion to form the ferrous HEDTA ligand radical complex, which is characterized by absorption maxima at 295 nm (epsilon = 2,640 M-1 cm-1) and 420 nm (epsilon = 620 M-1 cm-1). For the reaction of Fe(II)HEDTA with H2O2, the following mechanism is proposed: (Formula: see text) where k17 = 4.2 X 10(4) M-1 sec-1 and k19 = 5 +/- 0.2 sec-1.
Construction of the left coprime fractional representation for a class of nonlinear control systems

Abstract A constructive approach to the left coprime fractional representations for a class of (stable and unstable) nonlinear control systems described by certain multi-input/multi-output nonlinear ordinary differential equations is proposed. The method works for the coprimeness defined by Verma [15].
Triple-junction instability as cause for late Cenozoic extension and fragmentation of the western United States

Regional extension in the western United States began soon after 30 m.y. B.P., the time of first interaction between the Pacific and North American plates. Previous explanations for extension include lithospheric-active processes and asthenospheric-active processes; the former are favored because of coincidence of timing with lithospheric interactions, relative timing of volcanism and deformation, and coincidence with pre-existing structures. Although extension has occurred, in part, in a back-arc setting, it cannot be attributed to age of subducted crust or azimuth of subduction, because both attributes favor back-arc contraction (characteristic behavior before 40 m.y. B.P. The Mendocino triple junction has been unstable since its inception. The continental margin was relatively straight before 30 m.y. B.P., and it has become more convex westward as the triple junction has migrated northward. The continental margin and arc have been anchored to the subducting slab (Farallon-Juan de Fuca), whereas the triple junction must move parallel to the San Andreas transform. The combined result has been the northwestward and clockwise movement of coastal blocks relative to the continental interior and the eastward stepping of the San Andreas transform relative to the coast. These effects result from the unstable geometry of the Mendocino triple junction. Lack of a subducted slab (slab window) beneath the extended lithosphere enables asthenospheric rise but does not cause extension.
Spatial Vector Electrocardiography

A new method for the interpretation of conventional electrocardiographic leads is presented. It is based upon evidence that all body surface leads tend to record from the same resultant electrical forces. The various leads write different QRS and T contours in a given case, then, simply because the axis for each of the leads has a different direction in the electrical field and therefore registers different components of these electrical forces. The method has many advantages over "pattern" methods of interpretation. To illustrate its use, a study of QRS vectors is presented with special reference to the SlS2S3 pattern.
Kainate Receptors Differentially Regulate Release at Two Parallel Fiber Synapses

Presynaptic kainate receptors (KARs) facilitate or depress transmitter release at several synapses in the CNS. Here, we report that synaptically activated KARs presynaptically facilitate and depress transmission at parallel fiber synapses in the cerebellar cortex. Low-frequency stimulation of parallel fibers facilitates synapses onto both stellate cells and Purkinje cells, whereas high-frequency stimulation depresses stellate cell synapses but continues to facilitate Purkinje cell synapses. These effects are mimicked by exogenous KAR agonists and eliminated by blocking KARs. This differential frequency-dependent sensitivity of these two synapses regulates the balance of excitatory and inhibitory input to Purkinje cells and therefore their excitability.
The role of income in the formation of new cities

The richest neighborhoods in the unincorporated suburbs have a stronger incentive to form a new city to escape the redistribution that is occurring there. Wealthy families also may desire to establish a new city if this enables the provision of government services that middle income voters would not fund. With three different measures of household well being—based on educational attainment, income, and home values—we consistently found that the relatively wealthier neighborhoods were more likely to be part of a new city by the end of the decade. Population density also played a big role
161 REVERSED ALTERNATING WENCKEBACH PERIODICITY

Alternating Wenckebach periodicity (AWP) is defined as an pattern of 2:1 AV block associated with progressive lengthening of the conducted impulses with termination in a higher degree of block. We found another phenomenon in 5 children during atrial pacing which is the reverse of this pattern (RAWP) and has not been previously reported: that is, during an underlying pattern of 2:1 AV block, there is progressive shortening of the conducted impulses with termination in a lower degree of block. The mechanism can be explained by a one-level block model. It is formed by a series of self-perpetuating events: (1) The 1st beat of the RAWP is coupled to a preceding impulse with a short coupling interval (CI) and results in a long (the longest) delay. (2) With a long preceding delay the 2nd beat of the RAWP has a short (the shortest) CI falling within the effective refractory period of the AVN (ERP-AVN) and results in block. (3) Therefore the 3rd beat is actually coupled to the 1st beat with a long CI and results in a shorter delay. (4) The 4th beat also has long CI, which, if still shorter than the ERP-AVN results in a sequence of 2:1 block in which the conducted impulses showing progressive shortening. This continues until CI of the even numbered beat exceeds the ERP-AVN and, thereby, conducts.
Cytokeratin expression in the odontogenic keratocyst.

Abstract Purpose: This study attempted to identify differential cytokeratin expression in cystic jaw lesions using immunohistochemical staining. Patients and Methods: The charts from selected patients treated between 1983 and 1994 for jaw cysts were evaluated. Twenty-four paraffinized specimens were selected randomly for investigation with 5 immunohistochemical stains. The 4 diagnostic categories included ameloblastoma, dentigerous cyst, odontogenic keratocyst (OKC), and recurrent odontogenic keratocyst in patients with nevoid basal cell carcinoma (NBCC) syndrome. The 5 immunohistochemical stains included antibodies to cytokeratins 13, 17, and 18; CAM 5.2; AE 1/3; and carcinoembryonic antigen (CEA). Results: Differential staining of OKCs from patients with and without NBCC syndrome was found only with the antibody to cytokeratin 17. Furthermore, staining of OKCs in syndromic patients appeared to be stronger and more uniform than in nonsyndromic patients. Conclusions: These findings suggest that immunohistochemical staining for cytokeratin 17 may aid in the diagnosis of OKCs and may be used to further subdivide these lesions based on the presence or absence of NBCC syndrome. © American Association of Oral and Maxillofacial Surgeons
Using canonical correlation analysis to discover genetic regulatory variants.

Background Discovering genetic associations between genetic markers and gene expression levels can provide insight into gene regulation and, potentially, mechanisms of disease. Such analyses typically involve a linkage or association analysis in which expression data are used as phenotypes. This approach leads to a large number of multiple comparisons and may therefore lack power. We assess the potential of applying canonical correlation analysis to partitioned genomewide data as a method for discovering regulatory variants. Methodology/Principal Findings Simulations suggest that canonical correlation analysis has higher power than standard pairwise univariate regression to detect single nucleotide polymorphisms when the expression trait has low heritability. The increase in power is even greater under the recessive model. We demonstrate this approach using the Childhood Asthma Management Program data. Conclusions/Significance Our approach reduces multiple comparisons and may provide insight into the complex relationships between genotype and gene expression.