cssi/SciSciGPT-SciSciNet huggingface dataset:
Transient simulation of electron emission from quantum-wire structures.

We model a GaAs quasi-one-dimensional quantum wire in an applied longitudinal field and focus on mechanisms of electron emission leading to real-space transfer from the wire. The Monte Carlo simulation assumes an initial electron distribution in the wire and calculates the time required for electrons to undergo nonequivalent intervalley scattering to three-dimensional states. The model includes multiple subbands, polar optic and acoustic phonons, intervalley scattering, and band-structure nonparabolicity. Results have been obtained for different confinement conditions as well as different temperatures. We find that the required time is a very strong function of the longitudinal field and ranges from 4 ns down to 1 ps for fields in the range of 100 V/cm to 8 kV/cm. The corresponding distances in the wire vary from 130 \ensuremath{\mu}m down to the submicrometer range.
Trends in coronary revascularization 1989 to 1997: the Bypass Angioplasty Revascularization Investigation (BARI) survey of procedures.

Abstract Use of catheter-based and surgical coronary revascularization has steadily increased in North America. Introduction of catheter-based “new devices,” including intracoronary stents, has expanded the range of patients who can be treated with percutaneous approaches. We sought to address trends in the practice of catheter-based and surgical coronary revascularization during 1989 to 1997. The 17 North American institutions participating in the NHLBI Bypass Angioplasty Revascularization Investigation (BARI) periodically completed a 5-working day survey of all surgical and catheter-based coronary revascularizations. Data collected included patient demographics, vessel disease, prior interventions, and use of new devices or minimally invasive surgical techniques. The proportion of all procedures that were catheter based (vs surgical) increased from 52.1% in 1989/1990 to 62.0% in 1997 (p
Measurements and modeling of high-temperature, high-pressure density for binary mixtures of propane with n -decane and propane with n -eicosane

Abstract Binary mixture density data are reported for propane (C3) with n-decane (C10) and with n-eicosane (C20) at T = (320 to 525) K and pressures to 265 MPa. The (C3 + C10) mixture density data are in good agreement with available literature data to 70 MPa, which is the maximum reported literature pressure. There are no available binary mixture density data to compare to the (C3 + C20) mixture density data reported in the present study. The mixture density data are correlated with the Tait equation to facilitate interpolation of the data at different experimental conditions. Equations of state that are suitable for reservoir simulations are used to model the reported data. These models include the Peng–Robinson equation of state (PREoS), a volume-translated PREoS fit to high temperature, high pressure (HTHP) pure component density data, the PC-SAFT EoS, and modifications of the PC-SAFT EoS developed for better representation of HTHP data. The models give superior density predictions for (C3 + C10) mixtures compared to (C3 + C20) mixtures.
Application of active microwave thermography to inspection of carbon fiber reinforced composites

Inspection of carbon fiber reinforced polymer (CFRP) composites is very important in the aeronautical and transportation industries. Many nondestructive testing (NDT) techniques have been applied for health monitoring including ultrasound, thermography, etc. Although thermography has been widely used for this purpose, it often requires powerful heat lamps which may increase the risk of (thermal) damage to the structure under test. Thus, hybrid NDT methods have also been developed. Recently, the integration of microwave heating and thermography, herein referred to as Active Microwave Thermography (AMT), has also been considered as a potential health monitoring tool for infrastructure. This hybrid method uses microwave energy to heat a structure of interest, and subsequently the thermal surface profile is measured using a thermal camera. This paper investigates the potential of AMT for inspection of CFRP-rehabilitated airframes. Preliminary simulations and measurements indicate that AMT has the potential to detect disbonds under carbon fiber patches bonded to aluminum.
Liver coenzyme A levels in the vitamin B6-deficient rat.

Abstract Liver CoA concentration in the rat was decreased 50% by vitamin B6 deficiency and 66% by pantothenic acid deficiency. The decrease caused by vitamin B6 deficiency was independent of food intake and was not remedied by cystine supplementation of a 20% casein diet.
P‐116: A Multi‐Line Driving Scheme for R2R PM Ch‐LCD

A multi-line driving scheme simultaneously addressing two or more lines on cholesteric LCD (Ch-LCD) was proposed for faster addressing rate with low power consumption. The performance of the proposed driving scheme was experimentally evaluated on R2R PM Ch-LCD and satisfactory results of fast update and fine image quality were achieved.
Adaptive phase-array calibration using MIMO radar clutter

The goal of this paper is to develop methods for determining the calibrated array weights for uniform linear transmit and receive radar arrays necessary to achieve desired uniform sidelobe performance. The ability of current radar systems to suppress sidelobe clutter and interference is seriously limited by miscalibration of antenna array gain and phase due to non-ideal antenna and near-field scattering characteristics, both at the receive and transmit phased-arrays. At best, current calibration methods perform only receive array calibration using a limited number of discrete sources. The objective of this paper is to perform joint transmit and receive array calibration using ground backscatter returns from MIMO radar illumination.
Demonstration of low voltage and functionally complete logic operations using body-biased complementary and ultra-thin ALN piezoelectric mechanical switches

This paper reports, for the first time, on the demonstration of low voltage and functionally complete logic elements (NAND and NOR) implemented by using body-biased complementary and ultra-thin (250 nm thick) Aluminum Nitride (AlN) based piezoelectric mechanical switches. This work presents, firstly, the importance of scaling AlN films for the demonstration of ultra-thin AlN switches and, secondly, the implementation of a new actuation scheme based on body biasing to lower the switch threshold voltage. Four of these ultra-thin switches were connected together to synthesize functionally complete MEMS logic gates (NAND and NOR) with a ± 2V swing and a body-bias voltage ≪ 8 V.
Women's Film and Female Experience, 1940-1950

Women's Film and Female Experience takes a fresh look at a wide range of popular women's films in order to discover what American female consciousness in the 1940s was really about. The author traces the evolution and development of the Hollywood women's film, and describes the social history of American women in the 1940s. She then analyzes dominant narrative patterns within popular women's films of the decade: the maternal drama, the career woman comedy, and the films of suspicion and distrust.
The Ubiquity Paradox: Further Thinking on the Concept of User Centeredness

Where do words go to live when they become meaningless? —Anonymous Men of the world who value the Way all turn to books. But books are nothing more than words. Words have value; what is of value in words is meaning. —Zhuangzi (as quoted in Mao) For questioning is the piety of thought. —Heidegger in The Question ConcerningTechnology and Other Essays This essay argues that user centeredness has become ubiquitous and is in danger of being rendered meaningless. To address this problem, a meditative essay theorizes user centeredness by examining a base term—use—as defined through the ancient concepts of techne and the four causes of making. It concludes that user-centered design should employ the causes in order to avoid inversions during the development of all things technological.
Contributions to the second virial coefficient from the anisotropic interaction potential for molecules of arbitrary symmetry

Abstract A general expression is derived for the second virial coefficient of a gas of molecules of arbitrary symmetry under the assumption that the anisotropic part of the interaction potential is weak. The integral involved in the expression is evaluated in closed form for a Lennard-Jones (6–12) plus long-range anisotropic potential.
Personality and Attempted Suicide in Depressed Adults 50 Years of Age and Older: A Facet Level Analysis

We examined the contribution of personality traits to attempted suicide, the number of suicidal attempts, and suicidal ideation in a sample of depressed inpatients. Personality was assessed via the Revised NEO Personality Inventory (NEO-PI-R). Bivariate analyses showed that suicide attempters were more self-conscious, self-effacing, impulsive, and vulnerable to stress, and less warm, gregarious, and inclined to experience positive emotions. Multivariate regression analyses controlling for age, gender, severity of depression, and psychiatric comorbidity showed that patients with a lifetime history of attempted suicide were less inclined to experience positive emotions and be more self-effacing. Patients with more severe suicidal ideation were less warm and more self-effacing. Results indicated that specific personality traits confer risk for suicidal behaviors in middle age and older adults. Interventions tailored to specific personality profiles in this high-risk group should be developed, and their efficacy examined.
The cinema of Alexander Sokurov: figures of paradox

Alexander Sokurov, among the most celebrated masters of Russian cinema, was born in 1951 in Podorvikha (near Irkutsk), a town flooded into oblivion by a Soviet irrigation plan. As a child, the futu...
CRHSP-28 Regulates Ca2+-stimulated Secretion in Permeabilized Acinar Cells

Abstract CRHSP-28 is a Ca2+-regulated heat-stable phosphoprotein, abundant in the apical cytoplasm of epithelial cells that are specialized in exocrine protein secretion. To define a functional role for the protein in pancreatic secretion, recombinant CRHSP-28 (rCRHSP-28) was introduced into streptolysin-O-permeabilized acinar cells, and amylase secretion in response to elevated Ca2+ was determined. Secretion was enhanced markedly by rCRHSP-28 over a time course that closely corresponded with the loss of the native protein from the intracellular compartment. No effects of rCRHSP-28 were detected until ∼50% of the native protein was lost from the cytosol. Secretion was enhanced by rCRHSP-28 over a physiological range of Ca2+concentrations with 2–3-fold increases in amylase release occurring in response to low micromolar levels of free Ca2+. Further, rCRHSP-28 augmented secretion in a concentration-dependent manner with minimal and maximal effects occurring at 1 and 25 μg/ml, respectively. Covalent cross-linking experiments demonstrated that native CRHSP-28 was present in a 60-kDa complex in cytosolic fractions and in a high molecular mass complex in particulate fractions, consistent with the slow leak rate of the protein from streptolysin-O-permeabilized cells. Probing acinar lysates with rCRHSP-28 in a gel-overlay assay identified two CRHSP-28-binding proteins of 35 (pp35) and 70 kDa (pp70). Interestingly, preparation of lysates in the presence of 1 mm Ca2+ resulted in a marked redistribution of both proteins from a cytosolic to a Triton X-100-insoluble fraction, suggesting a Ca2+-sensitive interaction of these proteins with the acinar cell cytoskeleton. In agreement with our previous study immunohistochemically localizing CRHSP-28 around secretory granules in acinar cells, gel-overlay analysis revealed pp70 copurified with acinar cell secretory granule membranes. These findings demonstrate an important cell physiological function for CRHSP-28 in the Ca2+-regulated secretory pathway of acinar cells.
Sodium-dependent proline and glutamate uptake by hippocampal synaptosomes during postnatal development

Abstract Na+-dependent uptake of proline and glutamate by hippocampal synaptosomes was studied during postnatal development. At all ages from 9 days to adulthood, hippocampal synaptosomes transported proline by both a high-affinity and a low-affinity process, whereas glutamate was always transported predominantly by a high-affinity process. During the period of rapid synaptogenesis, the KT for high-affinity proline transport overshot the adult value, whereas the KT for glutamate transport increased steadily toward the adult value. The ratio of KT values for proline and glutamate was 2–3 times the adult value between 12 and 24 days of age. Although high-affinity transporters for proline and glutamate are expressed by nearly the same hippocampal pathways, they are differentially regulated during postnatal development.
Analysis of a multi-period pricing problem

Abstract We consider the pricing decision of a firm over a planning horizon ( T ) in a market with a finite potential population ( M ). New consumers enter the market every period according to a diffusion process. Consumers differ in their willingness to pay and form expectations about future prices. The credible prices in this system have to be recursively (over time) profit maximizing prices or subgame perfect equilibrium prices . The problem of determining the perfect equilibrium prices is equivalent to the problem of determining a price path in a network of consumer states that satisfies a set of subgame properties. The problem of determining the exact subgame perfect prices involves a state space that expands exponentially in the planning horizon ( T ). We present an aggregation procedure that generates approximate price paths that satisfy the subgame properties in an aggregated state space. We provide computational results for the constant rate of entry and diffusion of customers to the system that justify our claim that the procedures are fast and provide good approximations to the actual subgame perfect prices in the system.
A Transactional Model of Parental Involvement and Children's Achievement from Early Childhood through Adolescence

SYNOPSIS Objective. In a longitudinal study, researchers examined the transactional relations between two types of parental home involvement, academic instruction and academic socialization, and children's reading achievement from early childhood through adolescence. Academic instruction involves one-on-one interactions between parent and child that target the development of specific academic skills, and academic socialization involves parents' promotion of academic values, beliefs, and expectations. Design. The sample was based on an ongoing long-term longitudinal study, and included 122 children (approximately equal in gender) and their families. This study included data collected from ages 3 to 17 years, employing a variety of direct and indirect assessments Results. Findings showed that the two types of parental home involvement are distinct, related, and highly stable from early childhood through adolescence, and both types of parental home involvement show transactional relations with children's rea...
The Effect of Incremental Changes in Phonotactic Probability and Neighborhood Density on Word Learning by Preschool Children

Purpose Phonotactic probability or neighborhood density has predominately been defined through the use of gross distinctions (i.e., low vs. high). In the current studies, the authors examined the i...
Quantification of Allosteric Influence of Escherichia coli Phosphofructokinase by Frequency Domain Fluorescence

The allosteric properties of the wild-type Escherichia coli phosphofructokinase were compared to the E187A mutant by using frequency-domain techniques. Tryptophan-shifted mutants comprising of double (W311Y/Y55W and W/311F/F188W) and triple (W311Y/Y55W/E187A and W311F/F188W/E187A) amino acid residue changes, which allowed for better fluorescence probing at targeted sites, were also compared to the wild-type and E187A. The additive nature of multiple mutations allowed one to partition the net effect of modifying residue 187. In general, the mutant enzymes displayed greater heterogeneity in sub-state population than did the wild-type enzyme. The semi-cone angle model was used to quantify the extent of depolarization of the fluorophore. Use of the model presupposes that the extent of depolarization directly correlates with the degree of flexibility of the fluorophore. A relationship has been established between the values determined from the semi-cone angle calculations and the thermodynamic components responsible for the allosteric linkage between the regulatory and substrate binding. Coupling interactions giving rise to positive entropy components are manifested by increasing flexibility of the ternary complexes rather than the binary complexes.
A Massively Parallel Reservoir Simulator for Large Scale Reservoir Simulation

A Massively Parallel reservoir simulator (POWERS) has been developed and fully integrated with Suadi Aramco's pre and post processing graphical environment. The simulator has been validated against published results and other industrial simulators. Three different giant oil field studies using million grid blocks were carried out by using the new simulator. Benchmark runs indicated near linear performance improvement with linearly increasing number of processors. With the current capabilities mega cell construction, preprocessing and post processing is quite fast. History match runs involving over million grid block and 30-50 years of history is obtained in less than one hour on a low cost parallel computer.
Ducks and Green – An Introduction to the Ideas of Hypothesis Testing

Testing statistical hypotheses introduces new vocabulary, concepts and a way of thinking that some students might initially find difficult. We provide a simple case that can be used in class as a gentle introduction to the ideas and procedures of hypothesis testing.
Incorporating detection tasks into the assessment of CT image quality

The purpose of this study was to compare traditional and task dependent assessments of CT image quality. Chest CT examinations were obtained with a standard protocol for subjects participating in a lung cancer-screening project. Images were selected for patients whose weight ranged from 45 kg to 159 kg. Six ABR certified radiologists subjectively ranked these images using a traditional six-point ranking scheme that ranged from 1 (inadequate) to 6 (excellent). Three subtle diagnostic tasks were identified: (1) a lung section containing a sub-centimeter nodule of ground-glass opacity in an upper lung (2) a mediastinal section with a lymph node of soft tissue density in the mediastinum; (3) a liver section with a rounded low attenuation lesion in the liver periphery. Each observer was asked to estimate the probability of detecting each type of lesion in the appropriate CT section using a six-point scale ranging from 1 ( 90%). Traditional and task dependent measures of image quality were plotted as a function of patient weight. For the lung section, task dependent evaluations were very similar to those obtained using the traditional scoring scheme, but with larger inter-observer differences. Task dependent evaluations for the mediastinal section showed no obvious trend with subject weight, whereas there the traditional score decreased from ~4.9 for smaller subjects to ~3.3 for the larger subjects. Task dependent evaluations for the liver section showed a decreasing trend from ~4.1 for the smaller subjects to ~1.9 for the larger subjects, whereas the traditional evaluation had a markedly narrower range of scores. A task-dependent method of assessing CT image quality can be implemented with relative ease, and is likely to be more meaningful in the clinical setting.
Gender role abnormalities in boys: an analysis of clinical ratings.

In response to the need for more systematic descriptions of clinical impressions of effeminate boys, particularly at this time of changing social sex-role stereo types, extensive clinical ratings were made on a series of 29 boys, aged 5–13, and their families who had been referred to a project dealing with gender disturbance. Principal component analysis of these ratings indicated 4 orthogonal factors: Factor I, specific effeminate behaviors; Factor II, normalcy of family environment and childhood adjustment; Factor III, family overprotectiveness and associated fearfulness in the child; and Factor IV, social unresponsiveness and aversiveness in the children. Independently of the data analysis, subgroups were formed and t tests between the groups were computed for factor scores. Children judged as noneffeminate or midly effeminate were less effeminate (p<.001), came from more stereo typically normal families (p<.05), and tended to be less overprotected (p<.10) than highly effeminate children. Effeminate children between ages 5 and 7 tended to be more effeminate (p<. 10) and less overprotected (p< 10) than effeminate children between ages 8 and 10. These results are discussed in terms of their implications for clinical assessment of extreme effeminacy, their relationship to previous findings, and their contribution to understanding the meaning of clinical referral for problems of effeminacy.
The HIV-1 HLA-A2-SLYNTVATL Is a Help-Independent CTL Epitope

The CTL response to the HLA-A*0201-restricted, HIV-1 p17 Gag77–85 epitope (SLYNTVATL; SL9) has been extensively studied in patients. Although this reactivity is exceptionally prominent in chronically infected patients and inversely correlated to viral load, SL9-specific CTLs (SL9-CTLs) are rarely detected in acute infection. To explore the cellular basis for this unusual manifestation, SL9-CTLs primed ex vivo from naive circulating CD8+ T cells of healthy, seronegative donors were generated and characterized. SL9 appeared to differ from other well-studied A*0201-restricted epitopes in several significant respects. In contrast to published reports for influenza and melanoma peptides and the HIV gag IV9 epitope studied here in parallel, SL9-CTLs were primed by immature but not mature autologous dendritic cells. Highly activated SL9-CTLs produce sufficient autocrine mediators to sustain clonal expansion and CTL differentiation for months without CD4+ T cells or exogenous IL-2. Moreover, SL9-CTLs were sensitive to paracrine IL-2-induced apoptosis. IL-2 independence and sensitivity to paracrine IL-2 were also characteristic of SL9-CTLs immunized by dendritic cells transduced by a nonreplicating lentiviral vector encoding full-length Gag. In vitro-primed SL9-CTLs resembled those derived from patients in degeneracy of recognition and functional avidities for both SL9 and its natural mutations. Together, these data show that SL9 is a highly immunogenic, help-independent HIV epitope. The scarcity of SL9-CTLs in acute infection may result from cytokine-induced apoptosis with the intense activation of the innate immunity. In contrast, SL9-CTLs that constitutively produce autocrine help would predominate during CD4-diminished chronic infection.
Regulation of dihydropyridine receptor gene expression in mouse skeletal muscles by stretch and disuse

This study examined dihydropyridine receptor (DHPR) gene expression in mouse skeletal muscles during physiological adaptations to disuse. Disuse was produced by three in vivo models—denervation, te...
NEW RESULTS FROM THE BATES LARGE ACCEPTANCE SPECTROMETER TOROID (BLAST)

An experiment using the novel technique of scattering a longitudinally polarized electron beam from polarized internal hydrogen/deuterium gas targets was carried out in the South Hall Ring at the MIT-Bates Accelerator Center. The scattered particles were detected by the Bates Large Acceptance Spectrometer Toroid (BLAST) detector. The proton electric to magnetic form factor ratio, at Q2 = 0.1 - 0.65 (GeV/c)2 has been determined from the experiment by measuring the spin-dependent ep elastic scattering asymmetry in the two symmetric sectors of the BLAST simultaneously for the first time. The neutron electric form factor in the same Q2 range has been extracted by measuring the spin-dependent asymmetry from the process with a vector polarized deuterium target. These results on the nucleon form factors from the BLAST experiment are presented.
Components of reproductive isolation between the monkeyflowers Mimulus lewisii and M. cardinalis (Phrymaceae)

Evolutionists have long recognized the role of reproductive isolation in speciation, but the relative contributions of different reproductive barriers are poorly understood. We examined the nature of isolation between Mimulus lewisii and M. cardinalis, sister species of monkeyflowers. Studied reproductive barriers include: ecogeographic isolation; pollinator isolation (pollinator fidelity in a natural mixed population); pollen competition (seed set and hybrid production from experimental interspecific, intraspecific, and mixed pollinations in the greenhouse); and relative hybrid fitness (germination, survivorship, percent flowering, biomass, pollen viability, and seed mass in the greenhouse). Additionally, the rate of hybridization in nature was estimated from seed collections in a sympatric population. We found substantial reproductive barriers at multiple stages in the life history of M. lewisii and M. cardinalis. Using range maps constructed from herbarium collections, we estimated that the different ecogeographic distributions of the species result in 58.7% reproductive isolation. Mimulus lewisii and M. cardinalis are visited by different pollinators, and in a region of sympatry 97.6% of pollinator foraging bouts were specific to one species or the other. In the greenhouse, interspecific pollinations generated nearly 50% fewer seeds than intraspecific controls. Mixed pollinations of M. cardinalis flowers yielded >75% parentals even when only one-quarter of the pollen treatment consisted of M. cardinalis pollen. In contrast, both species had similar siring success on M. lewisii flowers. The observed 99.915% occurrence of parental M. lewisii and M. cardinalis in seeds collected from a sympatric population is nearly identical to that expected, based upon our field observations of pollinator behavior and our laboratory experiments of pollen competition. F1 hybrids exhibited reduced germination rates, high survivorship and reproduction, and low pollen and ovule fertility. In aggregate, the studied reproductive barriers prevent, on average, 99.87% of gene flow, with most reproductive isolation occurring prior to hybrid formation. Our results suggest that ecological factors resulting from adaptive divergence are the primary isolating barriers in this system. Additional studies of taxa at varying degrees of evolutionary divergence are needed to identify the relative importance of pre- and postzygotic isolating mechanisms in speciation.
Power of a simplified multivariate test for genetic linkage

In this paper we compare the power of the multivariate Haseman-Elston (MHE) test proposed earlier by Amos et al. (1990) and a computationally rapid new version of the multivariate Haseman-Elston test (NMHE) (Elston et al. 2000). We show that the power of NMHE was, for different simulation setups, identical or higher than that of MHE. In the bivariate case, the power of the NMHE method was somewhat less than that of the computationally intensive maximum likelihood variance components method (Amos et al. 2001). We present comparisons of the empirical distributions of the NMHE test to its limiting distributions for a range of numbers of traits. The distribution of the NMHE test appeared to conform satisfactorily to its limiting asymptotic distribution in large samples. Otherwise, empirical critical values for NMHE are somewhat higher than predicted, i.e. the test proposed by Elston et al. (2000) is non-conservative. The use of empirical critical values is therefore recommended for limited sample sizes (less than several hundred families). We also present the results of a linkage analysis performed by the NMHE method on a set of 4 body size-related traits. The method identified meaningful combinations of traits that showed significant linkage on chromosome 2 and suggestive linkage to regions on chromosomes 16 and 17.
A latent-trait based reliability estimate and upper bound

An estimate and an upper-bound estimate for the reliability of a test composed of binary items is derived from the multidimensional latent trait theory proposed by Bock and Aitkin (1981). The estimate derived here is similar to internal consistency estimates (such as coefficient alpha) in that it is a function of the correlations among test items; however, it is not a lowerbound estimate as are all other similar methods.
The splanchnic clearance rate of progesterone in patients with cardiac disease.

The splanchnic extraction of progesterone has been examined in men and women with cardiac disease of varied severity. Hepatic venous blood was sampled at the time of cardiac catheterization during the continuous infusion of 3H-progesterone and 131I-Rose Bengal. Splanchnic plasma flow in 16 subjects was 1117 ± 115 (se) 1/day; the plasma metabolic clearance rate (MCR) of progesterone was 1800 ± 142 (se) 1/day; the splanchnic extraction was 64.5 ± 3.1 (se) % and the splanchnic clearance of progesterone was calculated to be 704 ± 78.1 (se) 1/day. The splanchnic clearance of progesterone is therefore 41.5 ± 4.24 (se) % of the overall MCR and extrasplanchnic clearance is a major portion of the MCR of progesterone.
A Note on Nonautonomous Systems of Second-Order Differential Equations

The main objective of this paper is twofold. We first revisit the concept of doubly weighted pseudo-almost automorphy and discuss some additional properties of these functions. Next, we make extensive use of dichotomy tools to study and obtain the existence of doubly weighted pseudo-almost automorphic solutions to some nonautonomous second-order systems of differential equations. As an illustration, we will consider a nonresonance case for some scalar second-order systems of second-order differential equations.
Relative effectiveness of different first-year engineering seminars

The importance of first-year small group seminars in student retention has been well-documented by many researchers. The offerings of Purdue's Department of Freshman Engineering have varied over the years, with instructors continually striving to improve the format and content of the first-year seminar courses. A recent change to one of these seminars has prompted a preliminary evaluation of seminar effectiveness. Three seminars were investigated: ENGR 104, ENGR 103, and ENGR 100. ENGR 104, Introduction to Engineering and Purdue, is led by peer mentors and provides "survival skills" and insight into being an engineering student from the perspective of upper-division engineering students. ENGR 103, Introduction to Careers in Engineering, covers current engineering issues and/or research topics in addition to college "survival skills". ENGR 100, Freshman Engineering Lectures, is a large seminar introduction to the engineering disciplines that is required for all first-year engineering students. It can be taken alone or imbedded in ENGR 103 and ENGR 104. Engineering faculty leads both ENGR 103 and ENGR 100 from Purdue's schools of engineering. The primary objective of this research is to evaluate the ways the different seminar types (instructor-led versus student-led and small-group versus large lecture) may affect such outcomes as student satisfaction, confidence in major choice, academic performance, and retention in engineering. In this paper, differences in student retention, interest in and understanding of engineering disciplines and careers, and satisfaction with the seminar offering taken among students in the three different seminars is evaluated. Furthermore, the extent to which students are sure about their choice of major, to which the seminar contributed to this decision, and to which the seminar aided their academic and personal transition to college is discussed.
Phytoplankton seasonality in the central North Pacific: The endless summer reconsidered

Seventeen years of phytoplankton data from the eastern basin of the central North Pacific near 28”N, 155”W indicate that winter mixing is often deep enough to mix species from the deep phytoplankton association to the surface and that this mixing stimulates growth of these species. The frequency of deep winter mixing may be sufficient to have allowed the deep-living species to evolve a strategy of enhanced growth during a short winter, enabling them to survive a prolonged summer of restricted growth. In contrast, winter mixing may be unfavorable for the shallow flora, most species of which declined in abundance during winter. These seasonal cycles of shallow and deep-living species are independent. Hence, studies which consider only phytoplankton integrated through the euphotic zone may fail to detect pattern. In epipelagic environments of higher latitudes, the annual cycles of light, temperature, and wind are critical forcing parameters for planktonic communities. During winter, the cooling of surface waters and increased winddriven mixing bring new nutrients into the euphotic zone. After the onset of summer stratification, when phytoplankton are retained in the illuminated surface waters, these new nutrients support rapid production, often accompanied by rapid accumulation of phytoplankton biomass. This spring bloom influences not only productivity and standing stock of the ecosystem but also species composition and diversity. Seasonality is progressively damped at lower latitudes (Blackburn 198 1). The most extensive data from the central ocean basins are from the Sargasso Sea, especially from sites near Bermuda. Here, the winter mixed layer (isothermal layer) reaches an average depth of 140 m in February-March (Deuser 1987). However, there is considerable interannual variability (Jenkins and Goldman 1985), and Acknowledgments Through the years, many people have participated in the central Pacific study and have contributed directly or indirectly to this paper. Early studies with Richard Eppley and John McGowan gave rise to precursors of the model presented here, even as those observations led us to discount scasonality as an important factor. In the beginning, Arnold Mantyla postulated a seasonal cycle in the central Pacific based upon his knowledge of events in the outer
Detecting recurrent phase behavior under real-system variability

As computer systems become ever more complex and power hungry, research on dynamic on-the-fly system management and adaptations receives increasing attention. Such research relies on recognizing and responding to patterns or phases in application execution, which has therefore become an important and widely-studied research area. While application phase analysis has received significant attention, much of this attention thus far has focused on simulation-based studies. In these cycle-level simulations without indeterministic operating system intervention, applications display behavior that is repeatable from phase to phase and from run to run. A natural question, therefore, concerns how these phases appear in real system runs, where interrupts and time variability can influence the timing and behavior of the program. Our paper examines the phase behavior of applications running on real systems. The key goals of our work are to reliably discern and recover phase behavior in the face of application variability stemming from real system effects and time sampling. We propose a set of new, "transition-based" phase detection techniques. Our techniques can detect repeatable workload phase information from time-varying, real system measurements with less than 5% false alarm probabilities. In comparison to previous value-based detection methods, our transition-based techniques achieve on average 6x higher recurrent phase detection efficiency under real system variability.
Membrane-cytoskeleton adhesion and detachment from cells with "excess" area

The phospholipid membrane that encloses the living eucaryotic cell adheres to the underlying, actin-rich cytoskeleton of the cell. To study the adhesion of membrane to cytoskeleton one physically detaches the phospholipid membrane from the cytoskeleton by forming long, thin, membrane cylinders called "tethers." One measures the force on both the stationary and moving tether and then relates this force to the underlying adhesive, elastic and tensile properties of the membrane and cytoskeleton. Of current interest is the formation of tethers from cells with an excess of membrane area; i.e., with a readily available membrane reservoir contained in membrane folds and projections, collectively called microvilli.
Learning and development in neural networks: the importance of starting small

It is a striking fact that in humans the greatest learnmg occurs precisely at that point in time - childhood - when the most dramatic maturational changes also occur. This report describes possible synergistic interactions between maturational change and the ability to learn a complex domain (language), as investigated in connectionist networks. The networks are trained to process complex sentences involving relative clauses, number agreement, and several types of verb argument structure. Training fails in the case of networks which are fully formed and ‘adultlike’ in their capacity. Training succeeds only when networks begin with limited working memory and gradually ‘mature’ to the adult state. This result suggests that rather than being a limitation, developmental restrictions on resources may constitute a necessary prerequisite for mastering certain complex domains. Specifically, successful learning may depend on starting small.
Individual Odors in Djungarian Hamsters (Phodopus campbelli)

The sources of scent in Djungarian hamsters (Phodopus campbelli) that may be individually discriminated were investigated using an habituation paradigm. Male Djungarian hamsters were exposed to five presentations of a particular scent from one individual, and then to the same scent from a novel individual. Increased investigation of the scent from the novel individual indicated discrimination of scents from different individuals. Male hamsters distinguished individual differences in scents of other males from the midventral gland, urine, feces, mouth, and the corner of the mouth, which includes the sacculi; they did not discriminate among odors of different individuals when the scents were from the genital region, hindfeet, fur from behind ears or fur from the back. The results indicate that Djungarian hamsters have a repertoire of individually distinctive scents that are located in specific places on the body; these scents are not actively distributed to, nor passively picked up on, other parts of the body. The fact that scents from some areas do not contain individually distinctive information suggests that some sources may be specialized for producing individually distinctive scents.
Faster circle packing with application to nonobtuse triangulation

We show how to pack a non-simple polygon with O(n) tangent circles, so that the union of the polygon boundary components and circles is connected, in total time O(n log n). This improves a previous O(n log2 n) bound. By combining this with methods of Bern, Mitchell, and Ruppert we can extend this to a circle packing in which each portion of the polygon outside the circles is adjacent to at most four circles or boundary edges, and as a consequence we can triangulate the polygon with right and acute triangles, using O(n) Steiner points, again in the same O(n log n) time bound.
Pleasure and Illusion in Plato

Plato links pleasure with illusion, and this link explains his rejection of the view that all desires are rational desires for the good. The Protagoras and Gorgias show connections between pleasure and illusion; the Republic develops these into a psychological theory. One part of the soul is not only prone to illusions, but also incapable of the kind of reasoning that can dispel them. Pleasure appears good; therefore this part of the soul (the appetitive part) desires pleasures qua good but ignores reasoning about what is really good. Hence the new moral psychology of the Republic, not all desires are rational, and thus virtue depends on bringing one's non-rational desires under the control of reason.
Narrow QRS complex tachycardia: What is the mechanism?

A 30 year old female with history of atrio-ventricular nodal reentrant tachycardia (AVNRT) who underwent slow pathway modification at age of 12 years presented with recurrent palpitations and presyncope for one year. She was found to have recurrent supraventricular tachycardia sensitive to adenosine and was referred for electrophysiology study and catheter ablation. Baseline electrocardiogram showed sinus rhythm, RBBB, with no evidence of preexcitation. Electrophysiology study showed an AH 73ms, HV 48 ms, and RR 876 ms. Atrial extra-stimulus pacing showed no evidence of dual AV node physiology. Ventricular extra-stimulus pacing showed midline decremental conduction, figure 1A, and no change in the retrograde atrial activation sequence. Supraventricular tachycardia was consistently induced with single atrial extra-stimuli without an AH jump. Ventricular extra-stimuli never induced tachycardia. At baseline, the tachycardia had a cycle length of 450 ms, which decreased to 320–330 ms on isoproterenol, and occasionally, showed cycle length variability, figure 1B. Tachycardia always terminated with ventricular activation and the response to adenosine showed no retrograde VA conduction. Ventricular overdrive pacing at a cycle length of 310 ms when tachycardia had a CL of 330 ms is shown in figure 2A, and the response to atrial pacing at a cycle length of 310 ms, when tachycardia cycle length was otherwise stable at 320 ms, is shown in figure 2B. Entrainment from the ventricle repeatedly terminated tachycardia. Ventricular overdrive pacing at a CL much faster than the tachycardia lead to VA dissociation. Single His bundle refractory ventricular extra-stimuli reproducibly showed the response in figure 3 and on one occasion, terminated tachycardia. What is the mechanism of tachycardia? Figure 1 Panel A shows the response to ventricular extra-stimuli at 400/230 ms prior to ventricular effective refractory period. Panel B shows occasional oscillation in cycle lengths noted during tachycardia. HRA = high right atrium, His p = His bundle proximal, ... Figure 2 Panel A shows the response to ventricular over drive pacing at cycle length of 310 ms during tachycardia (tachycardia CL was 330 ms on isoproterenol). The arrow points to the first captured ventricular beat that leads to a change in the atrial activation ... Figure 3 The response to a His bundle refractory ventricular extra-stimulus at a time of stable tachycardia cycle length of 450 ms is shown. HRA = high right atrium, His p = His bundle proximal, His m = His bundle mid, His d = His bundle distal, CS = coronary ...
Limited Wegener's granulomatosis presenting as lung nodules in a patient with rheumatoid arthritis: a case report

Background Rheumatoid arthritis has varied pleuroparenchymal manifestations. Wegener's granulomatosis can develop in an established case of rheumatoid arthritis and this association although previously reported is very rare.
HOW DISCRETE ARE OAK SPECIES? INSIGHTS FROM A HYBRID ZONE BETWEEN QUERCUS GRISEA AND QUERCUS GAMBELII

The white oaks Quercus gambelii and Q. grisea overlap in distribution in New Mexico and Arizona. Within the region of overlap, there are numerous instances of contact between the two taxa. In some areas of contact morphologically, intermediate trees are common, whereas in others, morphologically intermediate trees are rare or absent. We describe a set of RAPD markers that distinguish between the two species and use these markers to examine patterns of gene exchange in an area of contact in the San Mateo Mountains of New Mexico. The markers are highly coincident with morphology and confirm that hybridization between the two species takes place. Despite the occurrence of hybrids, both species remain distinct, even in areas of sympatry, and marker exchange appears to be limited.
Patterns of electrolyte excretion in edema loss without the use of diuretics.

Sodium, potassium, chloride, and water losses were studied in patients while they lost all of their edema. The fluid which was excreted was hypotonic to body fluids, but did not change the osmotic concentration of the fluid that remained. Since the fluid excreted did not have the same composition as the edema fluid in the body, the interpretation of the results is that there is an internal redistribution and osmotic inactivation of a portion of the ions of the edema fluid of the body, and that the kidney is not the sole mechanism involved in the formation or loss of edema. Relating sodium loss to weight loss revealed two patterns; one group lost approximately 100 mEq. of sodium per kilogram of weight loss, and the other group lost less than 50 mEq. of sodium per kilogram. There is an indication that this difference is related to liver function.
Ocean backscatter distribution functions at mid incidence

A new model for the ocean backscatter distribution function at mid incidence is examined and found to be in excellent agreement with scatterometer data obtained during the SAXON FPN experiment. >
Therapy in the Great “Outdoors”:

Wilderness Therapy for Women: The Power of Adventure, Ellen Cole, Eve Erdman, and Esther D. Rothblum (Eds.). Binghamton, NY: Harrington Park Press, 1994. 262 pp., $12.95 (paper), ISBN: 1-56024-682-0.
Union Bound Analysis of Bit Interleaved Coded Orthogonal Modulation with Differential Precoding

A union bound on the performance of bit inter-leaved coded orthogonal modulation (BICOM) is presented. The bound is derived by representing the system as an equivalent serially concatenated convolutional code (SCCC). Differential precoding prior to orthogonal modulation is shown to provide an interleaver gain, and termination of the differential precoder with a tail bit is taken into account in the bound. The bounds are evaluated for both coherent and noncoherent detection in AWGN and fully interleaved Rayleigh fading and shown to be tight by comparison against simulation results.
Investigation on the Oxidation and Reduction of Titanium in Molten Salt with the Soluble TiC Anode

To reveal the oxidation process of titanium from TiC anode and the reduction mechanism of titanium ions in molten NaCl-KCl, the polarization curve of TiC anode in molten NaCl-KCl and cyclic voltammograms of the molten salt after polarization were studied. Investigation on the polarization curve shows that titanium can be oxidized and dissociated from the TiC anode at very low potential. The cyclic voltammograms demonstrated that the reduction reaction of titanium ions in the molten salt is a one-step process. By potentiostatic electrolysis, dendritic titanium is obtained on the steel plate. The work promotes the understanding on the process of electrochemical oxidization/dissociation of titanium from TiC anode and the reduction mechanism of titanium ions in molten salt.
A History of Instructional Design and Its Impact on Educational Psychology

The term instructional design has only come into use in education in the past decade. It refers to the process of systematically applying instructional theory and empirical findings to the planning of instruction. It is applied educational psychology in the best sense of the term. There is a clear focus on an instructional goal that represents what the learner will be able to do when the instruction is completed, the present skills of the learner, and how instruction will take place.