cssi/SciSciGPT-SciSciNet huggingface dataset:
Who Gets Started on Kickstarter? Racial Disparities in Crowdfunding Success

Crowdfunding platforms like Kickstarter are expected to "democratize" funding by increasing the availability of capital to traditionally underrepresented groups, but there is conflicting evidence about racial disparities in success rates. This paper contributes to the information systems literature on crowdfunding by examining the racial dynamics in the Kickstarter platform. In particular, we study three (sometimes conflicting) cues that allow potential backers to infer race: fundraiser photo, project photo, and textual content of project description. We create a novel data set comprised of project characteristics; the race of project and fundraiser photo subjects, determined using facial recognition software; and the full text of project descriptions. Our analysis results in three main findings. First, there are substantial differences in the textual content of project descriptions across racial groups. It is possible to predict with high accuracy the race of those associated with a Kickstarter project based only on the words in the description. Second, projects with Black fundraisers or subjects in project photos face significantly lower success rates, even when controlling for observable project characteristics and the textual content of project descriptions. Third, we address cases when the racial cues are not aligned. Race in the fundraiser photo has a greater effect on success probability than does race in the project photo; visually-identifiable race in general has a greater effect on success probability than does textually-identifiable race.The results expand information systems theory on crowdfunding, identity, and discrimination, utilize novel "big data" techniques, and yield empirical results that demonstrate bias in an important online platform. This work has important practical implications both for online platform designers and for users of said platforms.
Degradation of natural fiber in ternary blended cement composites containing metakaolin and montmorillonite

Abstract The influence of a coupled substitution of metakaolin and montmorillonite in Portland cement on degradation of natural fiber was investigated. In addition to durability of fiber-cement composites, degradation of the embedded natural fiber was directly investigated by means of tensile properties, crystallinity, chemical components and microstructure. The results indicate that the combination of these clay minerals validates their synergic effect on mitigating fiber’s deterioration by modifying hydration products and reducing alkalinity of pore solutions in cement. Correlations between cement hydration and fiber degradation demonstrate that both mineralization and alkali hydrolysis of natural fiber can be substantially mitigated through this method.
An Emerging Natural History in the Development, Mechanisms and Worldwide Prevalence of Major Mental Disorders

Conciliating recent findings from molecular genetics, evolutionary biology, and clinical observations together point to new understandings regarding the mechanism, development and the persistent worldwide prevalence of major mental disorders (MMDs), which should be considered the result of an evolutionary downside trade off. Temperamental/trait variability, by facilitating choices for individual and group responses, confers robustness flexibility and resilience crucial to success of our species. Extreme temperamental variants, originating evolutionarily from the asocial aspect of human nature, also constitute the premorbid personality of the disorders. The latter create vulnerable individuals out of whom some will develop MMDs but at much higher rate to that of the general population. Significantly, similar temperamental "lopsidedness" enables many of these vulnerable individuals, if intelligent, tenacious, and curious, to be creative and contribute to our survival while some may also develop MMDs. All have a common neural-developmental origin and share characteristics in their clinical expression and pharmacological responses also expressed as mixed syndromes or alternating ones over time. Over-pruning of synaptic neurons may be considered the trigger of such occurrences or conversely, the failure to prevent them in spite of it. The symptoms of the major mental disorders are made up of antithetical substitutes as an expression of a disturbed over-all synchronizing property of brain function for all higher faculties previously unconsidered in their modeling. The concomitant presence of psychosis is a generic common occurrence.
Retaining Critical Human Capital: Volunteer Firefighters in the Commonwealth of Pennsylvania

Effective delivery of services for the public good involves a multiplicity of organizations and actors, including those from the public, nonprofit, and private sectors. In some cases, service delivery is accomplished using programs that directly engage volunteers, including key public services like community-based and nonprofit volunteer fire departments. Volunteers in fire departments—often highly engaged volunteers with specialized training—provide vital services for a substantial portion of the United States, allowing local governments to realize considerable cost savings. Thus, issues of volunteer retention are a critical challenge for fire departments. Existing research has addressed issues of retention in a variety of settings; we argue that the challenging and particular context of fire departments is worthy of focused research. This article is an exploratory study of the predictors of voluntary firefighter retention in the Commonwealth of Pennsylvania. We use data from a web-based survey of volunteer firefighters to examine the factors that influence volunteer retention, focusing specifically on volunteer management practices and broader job-related concepts. Results indicate that volunteer training, performance management, job satisfaction, and organizational commitment influence both short- and mid-term intent to remain, indicating that management practices and programs, as well as other contextual factors that shape satisfaction and commitment, are important in retaining volunteers.
Chapter 16 – Brain death

The diagnosis of brain death should be based on a simple premise. If every possible confounder has been excluded and all possible treatments have been tried or considered, irreversible loss of brain function is clinically recognized as the absence of brainstem reflexes, verified apnea, loss of vascular tone, invariant heart rate, and, eventually, cardiac standstill. This condition cannot be reversed – not even partly – by medical or surgical intervention, and thus is final. Many countries in the world have introduced laws that acknowledge that a patient can be declared brain-dead by neurologic standards. The U.S. law differs substantially from all other brain death legislation in the world because the U.S. law does not spell out details of the neurologic examination. Evidence-based practice guidelines serve as a standard. In this chapter, I discuss the history of development of the criteria, the current clinical examination, and some of the ethical and legal issues that have emerged. Generally, the concept of brain death has been accepted by all major religions. But patients’ families may have different ideas and are mostly influenced by cultural attitudes, traditional customs, and personal beliefs. Suggestions are offered to support these families.
Historical Shadows: The Links between Sundown Towns and Contemporary Black–White Inequality:

I contribute to our understanding of black–white inequality in the United States by assessing the legacy of “sundown towns.” Sundown towns are places that restricted who could live there based on i...
Nucleotide Transport Through the Cystic Fibrosis Transmembrane Conductance Regulator

The cystic fibrosis transmembrane conductance regulator (CFTR) is a member of the superfamily of ATP-binding cassette (ABC) transporters, also known as traffic ATPases, which are implicated in the movement of various substrates. Recent studies indicate that CFTR and other closely related ABC transporters are also implicated in the movement of cellular ATP. This is the subject of current controversy. Therefore, evidence for the movement of cellular nucleotides by expression of CFTR and related molecules, as well as the potential significance of ATP-permeable channels in cell physiology, are reviewed in this study. The hypothesis is thus forwarded for the improper delivery of cellular ATP to the extracellular milieu by a dysfunctional CFTR, to be a relevant factor in the onset of cystic fibrosis.
The nature of the pituitary gonadotropins and their role in ovulation in a urodele amphibian (Ambystoma tigrinum)

Abstract Gonadotropic hormones were fractionated from pituitaries of the urodele amphibian Ambystoma tigrinum (tiger salamander) by methods previously employed to separate these hormones in other species of tetrapod vertebrates. These procedures yielded two distinct fractions that resembled the FSH and LH from other species in regard to their biological profiles in several nonmammalian bioassays and by their chromatographic behavior. The Ambystoma -FSH was free of LH activity ( Ambystoma -LH was highly potent in ovulation assays for LH; it also had a high activity in the Anolis lizard assay, but it is not clear whether this reflects high intrinsic activity or incomplete separation of FSH. In vitro studies with these and other (frog, turtle, mammalian) gonadotropins indicate that the induction of ovulation in Ambystoma , as in anurans, is highly specific for LH, independent of the source of the gonadotropins. These data support the view that two separate gonadotropins existed early in tetrapod evolution.
Introduction: At the Triple Point

This volume has an enigmatic title. The concept of “skiing at the triple point” is probably the key to this book. In many sports the properties of the playing field are relatively fixed and unchanged, and they remain so during the course of the play. That is definitely not so in skiing. A peculiar circumstance of skiing that it shares with one of its near relatives, ice skating, is that skiing can only be done on a playing field whose basic physical properties change. When we ski, small changes in temperature make huge changes in the playing surface. For skiing, the playing surface is water, which in the course of a single downhill run may exist in all its phases: as a solid (ice, in the form that we call snow); as a liquid; and even in the form of water vapor, as a gas. We shall see that, in many ways, skiing works best near 0 degrees Celsius (°C) or 32 degrees Farenheit (°F), which is roughly the temperature of the triple point of water. Thus we may say that we ski at the triple point—where the three possible states of water (solid, liquid, and vapor) coexist.
Decentralized Control Algorithm for the Hybrid Energy Storage of Shipboard Power System

This paper proposes a decentralized control algorithm for the medium-voltage direct current (MVDC) shipboard storage system to enhance the onboard survivability. The algorithm takes decisions based on local measurements, which makes it robust against cyber-attacks and able to provide a fast response. The voltage profile of the MVDC bus has sufficient information about the system status, which is utilized for managing the hybrid energy storage systems. Insertion/removal of the storage devices, such as batteries and supercapacitors, is made according to the mathematical morphology-based voltage processing and state-machine logic algorithms. To ensure proper power sharing, an adaptive droop control is used, taking into account consideration the state-of-charge of the storage units. Field-programmable gate array in the loop validation results confirms the ability of the proposed controller to maintain the MVDC bus voltage and the adequate operation of the storage entities simultaneously.
Modified lignin for composite and pellet binder applications

Lignin is a naturally occurring polymer that is present in all vascular plants. It binds together the cell walls, thus being one of the main structural components of vegetable tissue. In this project, alkali and dealkali lignins have been chemically modified in order to incorporate reactive fragments for subsequent free radical co-polymerisation with n-butyl methacrylate, styrene, or divinylbenzene (DVB). The thermal properties of regular and modified lignins were assessed and compared. The cross-linking of modified lignins with DVB yields materials with properties suitable for applications as a pellet binder, as well as a bio-based resin for the preparation of biocomposites. The chemical modification of alkali and dealkali lignin has been verified by Raman and infrared spectroscopies. The thermo-mechanical properties of the final materials prepared have been assessed by means of thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA), and are reported and discussed in this work.
Geometric phase invariance in spatiotemporal modulated elastic system

Abstract We study the topological characteristics of elastic waves in a one-dimensional mass and spring elastic superlattice that exhibits non-reciprocal elastic wave propagation due to extrinsic application of a single sinusoidal spatiotemporal modulation of its spring stiffness. We employ a computational procedure to generate the band structure, traveling modes' amplitudes and phases, and subsequently the geometric phases to characterize the global vibrational behavior of the system and its topological character. The elastic superlattice demonstrates the notion of non-conventional band structure, where hybridization gaps arise as bands appear and cross for certain wavenumber values. We estimate these hybridization points using multiple time scale perturbation theory for low modulation velocity. At the hybridization points, both the theoretical and numerical analyses display a discontinuity in the traveling modes’ amplitudes. Consequently, we find a multiple of π , sometimes zero, geometric phase value in the spatiotemporal modulated elastic system, if the unit cell has inversion symmetry as imposed by the values of the spring constant at the initial time. The temporal modulation, which creates hybridization gaps, changes the nature of the geometric phase from a closed loop geometric phase when the modulation is only spatial, to an open loop geometric phase. This open loop geometric phase is invariant to the temporal modulation.
Artificial Intelligence in Health in 2018: New Opportunities, Challenges, and Practical Implications.

Objective: To summarize significant research contributions to the field of artificial intelligence (AI) in health in 2018. Methods: Ovid MEDLINE® and Web of Science® databases were searched to identify original research articles that were published in the English language during 2018 and presented advances in the science of AI applied in health. Queries employed Medical Subject Heading (MeSH®) terms and keywords representing AI methodologies and limited results to health applications. Section editors selected 15 best paper candidates that underwent peer review by internationally renowned domain experts. Final best papers were selected by the editorial board of the 2018 International Medical Informatics Association (IMIA) Yearbook. Results: Database searches returned 1,480 unique publications. Best papers employed innovative AI techniques that incorporated domain knowledge or explored approaches to support distributed or federated learning. All top-ranked papers incorporated novel approaches to advance the science of AI in health and included rigorous evaluations of their methodologies. Conclusions: Performance of state-of-the-art AI machine learning algorithms can be enhanced by approaches that employ a multidisciplinary biomedical informatics pipeline to incorporate domain knowledge and can overcome challenges such as sparse, missing, or inconsistent data. Innovative training heuristics and encryption techniques may support distributed learning with preservation of privacy.
Princesas de cristal Ana López Recalde, Ignacio López-Goñi y Azucena Diez Editorial Almuzara. España; 2019. 168 páginas

A hard story full of suffering, about the fight against Anorexia nervosa, written by the patient, her father and the doctor who helped them
A decoder for the 3d color code with boundaries

We introduce a decoder for the 3D color code with boundaries, which is a variation of the restriction decoder introduced by Kubicka and Delfosse. Specifically, we adapt the lift procedure to efficiently find a correction on qubits adjacent to a boundary. We numerically estimate a threshold of $4\% - 8\%$ for Pauli $X$ errors and a threshold of $0.7\% - 0.8\%$ for Pauli $Z$ errors. Our work is a first step towards characterizing the performance of Bombin's recently proposed "colorful quantum computing."
The Corporate Chameleon

Who is an “officer” of a corporation? That is the straightforward, yet complex, question this Article seeks to examine and answer. Corporate law contemplates three distinct actors involved in the governance of the corporation–directors, stockholders, and officers. State corporate statutes make clear the identities of the first two actors, yet “officer” is left relatively undefined. The definitional uncertainty surrounding “officer” results in individuals moving in and out of officer status in a chameleon-like fashion. The variable nature of “officer” in corporate law is problematic because officer status carries with it distinct legal consequences. Linguistic precision is vital to the development, practice, and application of corporate law, but to achieve this there needs to be clear delineation of “officer”’s legal meaning. This is necessary for individuals to understand their legal responsibilities and authority, and lawyers and judges to communicate efficiently and effectively. If left unresolved, definitions will be determined ex post, allowing parties to opportunistically define “officer” to fit their particular argument or position. The recent rise of private ordering in corporate governance has highlighted the need for consensus and predictability with respect to delineating “officer” status. This paper proposes a prototype-centered definition of “officer” that incorporates both objective and subjective criteria. The result is a nuanced definition that accounts for the legal and traditional officer roles that are contemplated in corporate jurisprudence. The proposed definition accounts for existing statutory regimes and stabilizes the meaning of “officer” as a category of corporate actor.
Dermatological trends in emergency medicine.

Trends in emergency department (ED) visits with a primary dermatologic diagnosis are not well characterized. The goal is to determine how the number of ED visits attributable to dermatologic diseas...
Efficient Identification of Undetectable Two-Cycle Gate-Exhaustive Faults

As a superset of cell-aware faults, gate-exhaustive faults provide a target for the generation of a comprehensive test set. Considering two-cycle gate-exhaustive faults, the number of faults can be excessive, and many of the faults are undetectable. This paper considers the efficient identification of undetectable two-cycle gate-exhaustive faults. To take advantage of the large numbers of necessary assignments the faults have, the procedure described in the paper is based on the computation of input necessary assignments. The paper also notes that gates with large percentages of undetectable two-cycle gate-exhaustive faults are more important to target for test generation. Experimental results are presented for such gates in benchmark circuits.
Red cell distribution width is associated with mortality in non-anemic patients with COVID-19.

Introduction We have read with great interest the meta-analysis that examined the impact of increased red cell distribution width (RDW) and COVID-19 outcomes, conducted by Lee and colleagues, and recently published in the Journal of Medical Virology. The authors concluded that elevations in RDW were associated with adverse COVID-19 outcomes. However, the impact of elevation of RDW independent of anemia in COVID-19 remains to be clarified. Methods Patients ≥18 years who were diagnosed with COVID-19 at the Mount Sinai Health System between March 1 and April 1, 2020 and had a complete blood count (CBC) at presentation (n=2562) were selected to assess the association between RDW and mortality. Multivariable Cox proportional hazards regression models, stratified by presence of anemia, were performed to assess the independent association of RDW with mechanical ventilation and mortality. Results At univariate analysis, elevated RDW was statistically significantly associated with mechanical ventilation (p = 0.0109) and mortality (p Discussion In this study, we show that the elevated RDW association with mortality and mechanical ventilation is present exclusively in non-anemic patients. Therefore, we propose that RDW be considered by clinicians, especially in non-anemic patients, when risk-stratifying COVID-19 patients. This article is protected by copyright. All rights reserved.
Evaluation of a Multiethnic Polygenic Risk Score Model for Prostate Cancer.

Polygenic risk scores (PRS) of common genetic variants have shown promise in prostate cancer risk stratification, but their validity across populations has yet to be confirmed. We evaluated a multiethnic PRS model based on 269 germline genetic risk variants (261 were available for analysis) using an independent population of 13,628 U.S. men. The PRS was strongly associated with prostate cancer, but not with any other disease. Comparing men in the top PRS decile to those at average risk (40%-60%), the odds ratio of prostate cancer was 3.89 (95% confidence interval = 3.24 to 4.68) for men of European ancestry and 3.81 (95% confidence interval = 1.48 to 10.19) for men of African ancestry. By age 85, the cumulative incidence of prostate cancer for European American men was 7.1% in the bottom and 54.1% in the top decile. This suggests that the PRS can be used to identify a substantial proportion of men at high risk for prostate cancer.
Nonlinear Model Predictive Control of the Hydraulic Fracturing Process

Abstract Hydraulic fracturing has drawn significant attention over the past decade, as it can recover crude oil and natural gas from shale deposits previously considered inaccessible, which brings considerable economic benefits. However, hazardous operating conditions of extremely high pressure and environmental concerns require us to control this process carefully. Unfortunately, nonhomogeneous rock properties make this process difficult to control. Therefore, an accurate dynamic model and a well-designed controller are needed. In this work, we use the well-known Perkins-Kern-Nordgren (PKN) model with reformulation to solve the moving boundary problem. Next, the process is controlled by a standard Nonlinear Model Predictive Controller (NMPC) and multistage NMPC. We find that the process performance deteriorates under the influence of uncertainty with standard NMPC. When we control the process with standard NMPC, the pressure violation happens in one of the parameter mismatch cases. Nonetheless, when we apply multistage NMPC and consider the uncertainty evolution with a scenario tree, no constraint violations occur for all cases for both time-invariant and time-varying uncertainties. We also discuss the computational performance of different robust horizons for multistage NMPC. Our results demonstrate that the multistage NMPC is a promising approach to handle uncertainty caused by nonhomogeneous rock properties in the hydraulic fracturing process.
A perspective on the redox properties of tetrapyrrole macrocycles

Tetrapyrrole macrocycles serve a multitude of roles in biological systems, including oxygen transport by heme and light harvesting and charge separation by chlorophylls and bacteriochlorophylls. Synthetic tetrapyrroles are utilized in diverse applications ranging from solar-energy conversion to photomedicine. Nevertheless, students beginning tetrapyrrole research, as well as established practitioners, are often puzzled when comparing properties of related tetrapyrroles. Questions arise as to why optical spectra of two tetrapyrroles often shift in wavelength/energy in a direction opposite to that predicted by common chemical intuition based on the size of a π-electron system. Gouterman's four-orbital model provides a framework for understanding these optical properties. Similarly, it can be puzzling as to why the oxidation potentials differ significantly when comparing two related tetrapyrroles, yet the reduction potentials change very little or shift in the opposite direction. In order to understand these redox properties, it must be recognized that structural/electronic alterations affect the four frontier molecular orbitals (HOMO, LUMO, HOMO−1 and LUMO+1) unequally and in many cases the LUMO+1, and not the LUMO, may track the HOMO in energy. This perspective presents a fundamental framework concerning tetrapyrrole electronic properties that should provide a foundation for rational molecular design in tetrapyrrole science.
Growth of highly relaxed InGaN pseudo-substrates over full 2-in. wafers

A highly relaxed InGaN buffer layer was demonstrated over a full two-inch c-plane sapphire substrate by metalorganic chemical vapor deposition. The InGaN buffer layer was grown on a 100 nm GaN decomposition stop layer with a 3 nm thick high indium composition InGaN underlayer. After thermal decomposition of the underlayer at 1000 °C, a 200 nm thick In0.04Ga0.96N buffer showed 85% biaxial relaxation measured by a high resolution x-ray diffraction reciprocal space map. When used as a pseudo-substrate for the regrowth of InGaN/InGaN multi-quantum wells, the sample showed a 75 nm red-shift in room temperature photoluminescence when compared to a co-loaded GaN template reference. The longer emission wavelength is associated with higher indium incorporation in the InGaN layers from the lessening of the compositional pulling effect caused by compressive strain. Using this technique, a simple red light emitting diode was demonstrated with an active layer growth temperature of 825 °C and a peak wavelength of 622 nm at a current density of 20 A cm−2. This work represents a unique method to relax a III-nitride based layer over a full substrate.
Waterborne Polyurethanes for Corrosion Protection

Corrosion is a worldwide problem causing the loss of hundreds of thousands of dollars every year. Throughout this chapter, many topics regarding materials, procedures, synthetic routes, and mechanisms of waterborne polyurethane and their composites for corrosion protection are explored. Waterborne polyurethane-based coatings are an extremely versatile group of polymers that can be designed virtually to target any property, for example, thermal, mechanical, abrasion, and, most importantly, corrosion protection in different environments such as against air, moisture, seawater, chemicals, and UV radiation. The preparation of highly stable dispersions along with effective barrier effect for the coatings that include proper packing, high crosslink density, and strong adhesion to substrates are the key factors to develop an effective coating. In this chapter, the most relevant waterborne polyurethane-based composites mentioned in the current literature are discussed in detail to provide a full understanding of how anti-corrosive coatings work and how their properties can be further improved.
Lessons in Sustainable Development from China & Taiwan

1. Introduction 2. Theoretical Framework 3. Sustainable Development in Taiwan and China 4. Sustainable development programs and experiments 5. Directions for Future Study
The Fourth Dimension: Status Conflict in Groups

We argue that Jehn's (1995; 1997) conflict trichotomy of task, relationship and process conflict missed a fourth fundamental type of group conflict, that which occurs over relative status positions. Using mixed methods with two samples of MBA student teams, we identify and determine the impact of status conflicts in task groups. We first qualitatively identify the characteristics of status conflicts when they occur independently or with a conflict that is ostensibly over tasks, relationships or processes. We next validate a three-item survey scale that distinctly measures status conflict. Finally, we determine that including status conflict along with task and relationship conflict in analyzes of group performance and team member satisfaction both increases the explanatory power of the models and exerts a significant, negative main effect. Thus, some of the ambiguity in research on the effects of group conflict on performance may be resolved by recognizing status conflicts. In addition, emerging research on status contests will benefit from cohering around a single definition and measurement scale.
Culture Medium for Enterobacteria

A new minimal medium for enterobacteria has been developed. It supports growth of Escherichia coli and Salmonella typhimurium at rates comparable to those of any of the traditional media that have high phosphate concentrations, but each of the macronutrients (phosphate, sulfate, and nitrogen) is present at a sufficiently low level to permit isotopic labeling. Buffering capacity is provided by an organic dipolar ion, morpholinopropane sulfonate, which has a desirable pK (7.2) and no apparent inhibitory effect on growth. The medium has been developed with the objectives of (i) providing reproducibility of chemical composition, (ii) meeting the experimentally determined nutritional needs of the cell, (iii) avoiding an unnecessary excess of the major ionic species, (iv) facilitating the adjustment of the levels of individual ionic species, both for isotopic labeling and for nutritional studies, (v) supplying a complete array of micronutrients, (vi) setting a particular ion as the crop-limiting factor when the carbon and energy source is in excess, and (vii) providing maximal convenience in the manufacture and storage of the medium.
The Correlation Between Intron Length and Recombination in Drosophila: Dynamic Equilibrium Between Mutational and Selective Forces

Intron length is negatively correlated with recombination in both Drosophila melanogaster and humans. This correlation is not likely to be the result of mutational processes alone: evolutionary analysis of intron length polymorphism in D. melanogaster reveals equivalent ratios of deletion to insertion in regions of high and low recombination. The polymorphism data do reveal, however, an excess of deletions relative to insertions (i.e., a deletion bias), with an overall deletion-to-insertion events ratio of 1.35. We propose two types of selection favoring longer intron lengths. First, the natural mutational bias toward deletion must be opposed by strong selection in very short introns to maintain the minimum intron length needed for the intron splicing reaction. Second, selection will favor insertions in introns that increase recombination between mutations under the influence of selection in adjacent exons. Mutations that increase recombination, even slightly, will be selectively favored because they reduce interference among selected mutations. Interference selection acting on intron length mutations must be very weak, as indicated by frequency spectrum analysis of Drosophila intron length polymorphism, making the equilibrium for intron length sensitive to changes in the recombinational environment and population size. One consequence of this sensitivity is that the advantage of longer introns is expected to decrease inversely with the rate of recombination, thus leading to a negative correlation between intron length and recombination rate. Also in accord with this model, intron length differs between closely related Drosophila species, with the longest variant present more often in D. melanogaster than in D. simulans. We suggest that the study of the proposed dynamic model, taking into account interference among selected sites, might shed light on many aspects of the comparative biology of genome sizes including the C value paradox.
Dry melting of high albite

The properties of albitic melts are central to thermodynamic models for synthetic and natural granitic liquids. We have analyzed published phase-equilibrium and thermodynamic data for the dry fusion of high albite to develop a more accurate equation for the Gibbs free energy of this reaction to 30 kbar and 1400 degrees C. Strict criteria for reaction reversal were used to evaluate the phase-equilibrium data, and the thermodynamic properties of solid and liquid albite were evaluated using the published uncertainties in the original measurements. Results suggest that neither available phase-equilibrium experiments nor thermodynamic data tightly constrain the location of the reaction. Experimental solidus temperatures at 1 atm range from 1100 to 1120 degrees C. High-pressure experiments were not reversed completely and may have been affected by several sources of error, but the apparent inconsistencies among the results of the various experimentalists are eliminated when only half-reversal data are considered. Uncertainties in thermodynamic data yield large variations in permissible reaction slopes. Disparities between experimental and calculated melting curves are, therefore, largely attributable to these difficulties, and there is no fundamental disagreement between the available phase-equilibrium and thermodynamic data for the dry melting of albite. Consequently, complex speciation models for albitic melts, based on the assumption that these discrepancies represent a real characteristic of the system, are unjustified at this time.
100 GHz traveling‐wave electro‐optic phase modulator

Dramatic bandwidth enhancement has been achieved in a GaAs traveling‐wave electro‐optic phase modulator by the addition of a GaAs superstrate to suppress both velocity mismatch and electrical dispersion.
MARITAL DISSOLUTION, REMARRIAGE, AND CHILDBEARING

Earlier models of fertility hypothesize that marital dissolution and remarriage influence subsequent childbearing. This issue is examined by comparing the fertility of those in disrupted marriages with that of those in stable marriages. The results indicate that, by transferring women into a nonmarried status, marital dissolution decreases childbearing. The data also suggest that discord reduces fertility even before separation occurs--separated women had reduced fertility during the two years just before separation. It was found that marital dissolution without remarriage operates to truncate childbearing, thus decreasing family size. Dissolution followed by remarriage, however, lengthens the childbearing span of whites and has no inflences on average family size; remarrying white women are able to make up for the childbearing lost between marriages. For nonwhites, we found that dissolution and remarriage increase the average time to childbirth, but, even more importantly, these events greatly decrease the number of children born.
Optic nerve avulsion from a golfing injury.

Abstract PURPOSE: To describe a patient with optic nerve avulsion after being struck in the eye with a golf club. METHODS: A 10-year-old male was hit in the left eye by a golf club. The patient underwent full ophthalmoscopic evaluation and neuroimaging. RESULTS: The patient had no light perception in the left eye when first seen. Avulsion of the optic nerve with vitreous hemorrhage was apparent on examination. Computed tomographic imaging of the brain and orbits revealed no abnormalities. CONCLUSIONS: Optic nerve avulsion from golf-related injury is more likely to occur when the impact site is between the globe and the orbital rim. Rupture of the globe is more likely to occur with direct impact to it.
CONGENITAL VIRILIZING ADRENAL HYPERPLASIA IN IDENTICAL TWINS

ABSTRACT Congenital virilizing adrenal hyperplasia in identical female twins 7½ years of age is reported. The diagnosis was based on hypertrophy of the clitoris at birth, progressive virilization and accelerated growth, elevated urinary 17-ketosteroids and pregnanetriol, female sex chromatin pattern and amelioration with corticosteroid therapy. There is only 1 other authenticated example in the medical literature. This is not unexpected, since the anticipated incidenceis probably less than 1 per 23 million births. Therapeutic trials with intramuscular injections of a long-acting hydrocortisone preparation, oral prednisone, fluorohydrocortisone and methylprednisolone did not consistently suppress adrenal androgen production but (except for methylprednisolone) did induce Cushingoid phenomena. Cortisone (25 mg.) or prednisone (8 mg.) given intramuscularly every other day successfully suppressed adrenal hyperfunction without causing untoward side-effects.
New Strategies in Finnish Independent Television Production

AbstractThis article investigates independent television production and business strategies used by small and fairly new companies in that industry. It reintroduces Mintzberg’s concept of emerging strategies and emphasizes the role of network, both as a theoretical approach and as an important real-life strategy for small companies. In empirical terms, we identify five general strategies applied by independent companies: (1) Quality, (2) Specialization, (3) Broad market scope, (4) Beyond broadcast, and (5) Networking. Our categorization is based on personal interviews with 26 independent television production companies in Finland. Our main findings show that an increasing part of the business activities are designed for other purposes than traditional broadcasting. However, many companies manage to keep one foot in traditional television and the other in the emerging niches of television and new media hybrids. The global crisis of public service television will make independent companies even more incline...
Isotopic fractionation during ion filtration; I, Theory

Abstract Fractionation of the isotopes of H, O, and Cl during flow of aqueous solutions through semipermeable clay discs has been observed in the laboratory. The observed isotopic abundance trends of these elements in deep sedimentary basins have been attributed to similar phenomena. However, the mechanism responsible for such isotopic fractionation has not been identified. We propose that the fractionation of O and H isotopes in the water molecule results from increased activity of the heavy isotopic species in the membrane solution because high cation concentrations in the membrane pore fluid increase hydrationsphere fractionation effects. The heavy isotopic species thus diffuse away from the membrane and therefore are concentrated behind it. Predictions based on this theory satisfactorily model both laboratory and field observations. We propose that the fractionation of chlorine isotopes is a result of differences in the ionic mobility of 35Cl− and 37Cl−. Negative charges on the membrane repel the isotopic species at slightly different velocities against the uniform advective motion of the bulk water and thus the more mobile 35Cl− is enriched behind the membrane. Predictions calculated from this theory compare well with laboratory and field data.
Singularity of Contact-Edge Stress in Laminated Composites Under Uniform Extension

The unusually large and possibly infinite stress at the contact-edge is one of the factors responsible for delamination when the composite is subjected to ex ternal loading. Since more composites are now used in space vehicles, it is im portant to analyze the nature of the stress singularities at the contact-edge so that special attention can be paid to the design of mechanical fastenings and joints. In this paper we study the stress singularities at the contact-edge of an in terface between two adjacent layers in a laminated composite. Each layer of the composite is assumed to be of the same orthotropic material with one of the principal axes being the fiber direction. However, the angle θ which is the fiber orientation, varies from layer to layer. The composite is subjected to uniform extension in the plane of the layers. It is shown that a singularity of the type krδ (δ<0) may exist, but that it depends on the stacking sequence of the layers and the complete boundary conditions.
Optimal Campaign in the Smoking Dynamics

We present the optimal campaigns in the smoking dynamics. Assuming that the giving up smoking model is described by the simplified PLSQ (potential-light-smoker-quit smoker) model, we consider two possible control variables in the form of education and treatment campaigns oriented to decrease the attitude towards smoking. In order to do this we minimize the number of light (occasional) and persistent smokers and maximize the number of quit smokers in a community. We first show the existence of an optimal control for the control problem and then derive the optimality system by using the Pontryagin maximum principle. Finally numerical results of real epidemic are presented to show the applicability and efficiency of this approach.
Using and Selecting Graphic Techniques to Acquire Structural Knowledge

Structural knowledge, the knowledge of relationships between concepts in a content area, is essential for comprehension and problem solving. Learning structural knowledge can be facilitated through learner-generated two-dimensional diagrams of conceptual relationships. These diagrams include networks, concept maps, pattern notes, semantic maps and graphic organizers. In this paper, we describe the characteristics of graphic techniques and the cognitive processes that learners use to construct the diagrams. We then propose a model that can be used to choose between different graphic techniques based upon the cognitive processes elicited by the techniques and the learning outcomes derived from their use.
Hypothalamic-pituitary-adrenocortical axis activity and immune function after oral exposure to benzene and toluene

Benzene and toluene, commonly used solvents, possess neurotoxic and immunotoxic effects. Male CD-1 mice were continuously fed drinking water containing 0, 31, 166 and 790 mg/l benzene and 0, 17, 80 and 405 mg/l toluene, respectively. The concentrations of hypothalamic norepinephrine (NE) and its metabolite vanillylmandelic acid (VMA), circulating corticosterone and adrenocorticotropic hormone (ACTH), and lymphocyte-derived interleukin-2 (IL-2) activity were evaluated after 28 days of exposure to each solvent. Serum corticosterone was also measured at pretreatment, 2, 7, and 14 days of exposure. The concentrations of NE, VMA, ACTH and corticosterone were increased following exposure to these solvents. Benzene increased corticosterone levels in mice after 7 days (166 and 790 mg/l) and at 28 days (790 mg/l). Toluene elevated corticosterone levels at 14 and 28 days at the 405 mg/l exposure. IL-2 production by mouse T-lymphocytes was suppressed in the two higher benzene-treated groups, while toluene decreased IL-2 synthesis at the highest level only. Both benzene and toluene exposures stimulated hypothalamic-pituitary-adrenocortical (HPA) activity. Elevated corticosterone has been reported to inhibit IL-2 production and impair immunocompetence. Organic solvents may have, at least partially, an additive adverse effect on immune function via activated HPA status.
Data-Driven Learning of Q-Matrix

The recent surge of interests in cognitive assessment has led to developments of novel statistical models for diagnostic classification. Central to many such models is the well-known Q-matrix, which specifies the item–attribute relationships. This article proposes a data-driven approach to identification of the Q-matrix and estimation of related model parameters. A key ingredient is a flexible T-matrix that relates the Q-matrix to response patterns. The flexibility of the T-matrix allows the construction of a natural criterion function as well as a computationally amenable algorithm. Simulations results are presented to demonstrate usefulness and applicability of the proposed method. Extension to handling of the Q-matrix with partial information is presented. The proposed method also provides a platform on which important statistical issues, such as hypothesis testing and model selection, may be formally addressed.
“Clean up your plate”: Effects of child feeding practices on the conditioning of meal size

Abstract To obtain information on the development of the learned control of food intake, preschool children (N = 22) participated in conditioning and extinction trials to determine whether meal size could be conditioned. Each trial consisted of a two-part snack in which consumption of a fixed amount of a distinctively flavored high (145 kcal) or low (60 kcal) caloric density preload was followed by ad lib consumption of snacks. Following the pairs of conditioning trials, extinction test trials were given in which the flavors previously paired with either high or low caloric density were presented in intermediate, isocaloric preloads. Conditioning occurred in one of two child feeding contexts: one that focused children on internal cues of hunger and satiety, or one that focused the children on external cues, including the amount of food remaining on the plate. The external group also could receive rewards for eating. Only the children in the internal context showed evidence of responsiveness to caloric density cues and associative conditioning, eating more ad lib following the low-density preload than following the high density preload during conditioning, and eating more during extinction following the flavor previously paired with low caloric density. Children in the external context showed no evidence of responsiveness to caloric density cues, but increased in ad lib consumption across the conditioning trials.
Non-induced isomorphisms of matrix rings

We give examples of distinct integersi, j, and ringsT for which the matrix ringsM i (T) andM j (T) are isomorphic as rings, but for which the free modules T T (i) and T T (i) are non-isomorphic asT-modules.
On the class of limit reliability functions of homogeneous series-k-out-of-n systems

The problem of finding possible limit reliability functions of basic systems is well known. For instance Gnedenko [Ann. Math. 44 (1943) 432-453] has found a class of possible limit reliability functions for series and parallel systems. Smirnov [Trudy Matem. Inst. im. V.A. Stelkova, 1949] has solved the problem for ''k-out-of-n'' systems. In this paper these two areas are brought together and a class of limit reliability functions of homogeneous series-''k-out-of-n'' systems is presented. Moreover some applications are given as well.
Services for students with learning disabilities in U.S. and Canadian medical schools.

Between September 1, 1990, and March 31, 1991, 103 of the 142 medical schools in the United States and Canada responded to a questionnaire regarding their services and programs for learning-disabled medical students. Ninety-three schools accepted such students (and ten did not), but only two-thirds had support programs and half lacked the capacity to diagnose learning disability disorders. Twenty-five did not know they could administer licensing examinations in a nonstandard manner, and 19 had no senior administrator or faculty member coordinating learning disability services. The author concludes that these results suggest that medical schools are poorly informed about and unprepared to help learning-disabled students.