cssi/SciSciGPT-SciSciNet huggingface dataset:
Exploring Automatic Short Answer Grading as a Tool to Assist in Human Rating

This project proposes using BERT (Bidirectional Encoder Representations from Transformers) as a tool to assist educators with automated short answer grading (ASAG) as opposed to replacing human judgement in high-stakes scenarios. Many educators are hesitant to give authority to an automated system, especially in assessment tasks such as grading constructed response items. However, evaluating free-response text can be time and labor costly for one rater, let alone multiple raters. In addition, some degree of inconsistency exists within and between raters for assessing a given task. Recent advances in Natural Language Processing have resulted in subsequent improvements for technologies that rely on artificial intelligence and human language. New, state-of-the-art models such as BERT, an open source, pre-trained language model, have decreased the amount of training data needed for specific tasks and in turn, have reduced the amount of human annotation necessary for producing a high-quality classification model. After training BERT on expert ratings of constructed responses, we use subsequent automated grading to calculate Cohen’s Kappa as a measure of inter-rater reliability between the automated system and the human rater. For practical application, when the inter-rater reliability metric is unsatisfactory, we suggest that the human rater(s) use the automated model to call attention to ratings where a second opinion might be needed to confirm the rater’s correctness and consistency of judgement.
Language transfer theory and its policy implications: exploring interdependence between Luganda, Runyankole-Rukiga, and English in Uganda

The aim of the current study is to expand our understanding of cross-linguistic transfer (CLT) to new languages and settings under-represented in the research literature. Empirical evidence of CLT ...
Detecting Gestures Through a Gesture-Based Interface to Teach Introductory Programming Concepts

The goal of this research is to find an algorithm that is capable of recognizing gestures drawn in a visual and gesture-driven interface used to teach introductory programming concepts. Our system combines components from Google’s Blockly, a visual programming language with a drag-and-drop puzzle piece interface, and Microsoft’s Xbox Kinect which is used to perform skeletal tracking. We focus on two supervised machine learning clustering algorithms, centroid matching and medoid matching, to detect gestures.
Current Ultrasound Technologies and Instrumentation in the Assessment and Monitoring of COVID-19 Positive Patients

Since the emergence of the COVID-19 pandemic in December of 2019, clinicians and scientists all over the world have faced overwhelming new challenges that not only threaten their own communities and countries but also the world at large. These challenges have been enormous and debilitating, as the infrastructure of many countries, including developing ones, had little or no resources to deal with the crisis. Even in developed countries, such as Italy, health systems have been so inundated by cases that health care facilities became oversaturated and could not accommodate the unexpected influx of patients to be tested. Initially, resources were focused on testing to identify those who were infected. When it became clear that the virus mainly attacks the lungs by causing parenchymal changes in the form of multifocal pneumonia of different levels of severity, imaging became paramount in the assessment of disease severity, progression, and even response to treatment. As a result, there was a need to establish protocols for imaging of the lungs in these patients. In North America, the focus was on chest X-ray and computed tomography (CT) as these are widely available and accessible at most health facilities. However, in Europe and China, this was not the case, and a cost-effective and relatively fast imaging modality was needed to scan a large number of sick patients promptly. Hence, ultrasound (US) found its way into the hands of Chinese and European physicians and has since become an important imaging modality in those locations. US is a highly versatile, portable, and inexpensive imaging modality that has application across a broad spectrum of conditions and, in this way, is ideally suited to assess the lungs of COVID-19 patients in the intensive care unit (ICU). This bedside test can be done with little to no movement of the patients from the unit that keeps them in their isolated rooms, thereby limiting further exposure to other health personnel. This article presents a basic introduction to COVID-19 and the use of the US for lung imaging. It further provides a high-level overview of the existing US technologies that are driving development in current and potential future US imaging systems for lung, with a specific emphasis on portable and 3-D systems.
Association of sedentary time with blood pressure in women of reproductive age.

Abstract While the beneficial impact of moderate-vigorous physical activity (MVPA) on blood pressure is well-understood, the relationship between sedentary time (ST) and blood pressure is less clear. We aimed to evaluate the associations between ST and BP in reproductive-age women. This cross-sectional analysis consisted of 431 women enrolled in the Placenta as a Window to Maternal Microvascular Disease Risk study at Magee-Womens Hospital. Blood pressure and self-reported physical activity and ST were collected 8–10 years after delivery at study enrollment. Logistic and linear regression models examined associations between ST and blood pressure and adjusted for MVPA. Women with the highest amount of ST were less likely to be normotensive and more likely to have elevated blood pressure and Stage II hypertension (p = 0.02). Each additional hour of ST was associated with an increased risk of Stage II hypertension (OR 1.12 [1.01–1.24]) and higher systolic blood pressure (0.45 mmHg [0.08–0.82]), diastolic blood pressure (0.29 mmHg [0.02–0.56]), and mean arterial pressure (0.34 mmHg [0.05–0.63]), after adjustment for covariates. This relationship was more apparent in women who participated in less MVPA (bottom 50th percentile) versus more MVPA (top 50th percentile). ST is associated with higher blood pressure, particularly in women who engage in less aerobic activity, and could serve as an important intervention target for reducing blood pressure and hypertension during the reproductive years.
Differential abilities to engage inaccessible chromatin diversify vertebrate HOX binding patterns.

While Hox genes encode for conserved transcription factors (TFs), they are further divided into anterior, central, and posterior groups based on their DNA-binding domain similarity. The posterior Hox group expanded in the deuterostome clade and patterns caudal and distal structures. We aim to address how similar HOX TFs diverge to induce different positional identities. We studied HOX TF DNA-binding and regulatory activity during an in vitro motor neuron differentiation system that recapitulates embryonic development. We find diversity in the genomic binding profiles of different HOX TFs, even among the posterior group paralogs that share similar DNA binding domains. These differences in genomic binding are explained by differing abilities to bind to previously inaccessible sites. For example, the posterior group HOXC9 has a greater ability to bind occluded sites than the posterior HOXC10, producing different binding patterns and driving differential gene expression programs. From these results, we propose that the differential abilities of posterior HOX TFs to bind to previously inaccessible chromatin drive patterning diversification.
Integrity of clinical information in radiology reports documenting pulmonary nodules

OBJECTIVE Quantify the integrity, measured as completeness and concordance with a thoracic radiologist, of documenting pulmonary nodule characteristics in CT reports and assess impact on making follow-up recommendations. MATERIALS AND METHODS This Institutional Review Board-approved, retrospective cohort study was performed at an academic medical center. Natural language processing was performed on radiology reports of CT scans of chest, abdomen, or spine completed in 2016 to assess presence of pulmonary nodules, excluding patients with lung cancer, of which 300 reports were randomly sampled to form the study cohort. Documentation of nodule characteristics were manually extracted from reports by 2 authors with 20% overlap. CT images corresponding to 60 randomly selected reports were further reviewed by a thoracic radiologist to record nodule characteristics. Documentation completeness for all characteristics were reported in percentage and compared using χ2 analysis. Concordance with a thoracic radiologist was reported as percentage agreement; impact on making follow-up recommendations was assessed using kappa. RESULTS Documentation completeness for pulmonary nodule characteristics differed across variables (range = 2%-90%, P < .001). Concordance with a thoracic radiologist was 75% for documenting nodule laterality and 29% for size. Follow-up recommendations were in agreement in 67% and 49% of reports when there was lack of completeness and concordance in documenting nodule size, respectively. DISCUSSION Essential pulmonary nodule characteristics were under-reported, potentially impacting recommendations for pulmonary nodule follow-up. CONCLUSION Lack of documentation of pulmonary nodule characteristics in radiology reports is common, with potential for compromising patient care and clinical decision support tools.
Asymptotic Green's Functions for Source and Field Points on a Faceted Convex Surface

The uniform geometrical theory of diffraction (UTD) solution for mutual coupling is applied to a faceted conducting convex surface to predict the asymptotic Green's functions for electric and magnetic fields at a field point due to infinitesimal electric and magnetic currents at a source point, both points being on the surface. A quadratic surface mapping is used to introduce surface curvature to triangular facets. A previously developed geodesic ray tracing algorithm is applied to identify geodesic ray paths between source and field points on a faceted convex surface. The geometrical parameters extracted from the surface are used to apply the UTD solution to predict the asymptotic Green's functions. The results of the application of UTD to a faceted convex surface is validated with those of the analytical UTD solution for a circular cylinder and a sphere. This approach is applicable to arbitrary faceted convex surfaces.
Modulation of the IGF1R-MTOR pathway attenuates motor neuron toxicity of human ALS SOD1G93A astrocytes.

ALS (amyotrophic lateral sclerosis), the most common motor neuron disease, causes muscle denervation and rapidly fatal paralysis. While motor neurons are the most affected cells in ALS, studies on the pathophysiology of the disease have highlighted the importance of non-cell autonomous mechanisms, which implicate astrocytes and other glial cells. In ALS, subsets of reactive astrocytes lose their physiological functions and become toxic for motor neurons, thereby contributing to disease pathogenesis. Evidence of astrocyte contribution to disease pathogenesis are well established in cellular and animal models of familial ALS linked to mutant SOD1, where astrocytes promote motor neuron cell death. The mechanism underlying astrocytes reactivity in conditions of CNS injury have been shown to involve the MTOR pathway. However, the role of this conserved metabolic signaling pathway, and the potential therapeutic effects of its modulation, have not been investigated in ALS astrocytes. Here, we show elevated activation of the MTOR pathway in human-derived astrocytes harboring mutant SOD1, which results in inhibition of macroautophagy/autophagy, increased cell proliferation, and enhanced astrocyte reactivity. We demonstrate that MTOR pathway activation in mutant SOD1 astrocytes is due to post-transcriptional upregulation of the IGF1R (insulin like growth factor 1 receptor), an upstream positive modulator of the MTOR pathway. Importantly, inhibition of the IGF1R-MTOR pathway decreases cell proliferation and reactivity of mutant SOD1 astrocytes, and attenuates their toxicity to motor neurons. These results suggest that modulation of astrocytic IGF1R-MTOR pathway could be a viable therapeutic strategy in SOD1 ALS and potentially other neurological diseases.
Spontaneous pneumomediastinum: A rare complication of COVID-19 pneumonia

A novel coronavirus was identified at the end of December 2019 as the cause of a cluster of pneumonia cases in Wuhan, China. The virus that causes Coronavirus diseases-19 ( COVID-19) is designated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The clinical manifestations of COVID -19 and complications are evolving. Cardiac, renal, neurologic complication and coagulopathy has been reported in the literature. Here we present a case of spontaneous pneumomediastinum who tested positive for COVID -19 . A 45 years old female who was admitted after a reverse transcriptase-polymerase chain reaction (RT-PCR) test-confirmed COVID-19. She was experiencing worsening dyspnea. Initial laboratory investigation showed white blood cells of 7.49 [differential: 80.5% neutrophils and 13.6% lymphocytes]. Procalcitonin was 0.12, lactate dehydrogenase was 701, ferritin was 586, fibrinogen was more than 600, D-dimer was 0.56, CRP was 9.9. Arterial blood gas showed pH 7.44, PCO2 54 mmHg, and PO2 85.7 mmHg on 85% FiO2 heated high flow nasal cannula oxygen. A chest x-ray showed bilateral interstitial and alveolar opacities. A diagnosis of acute respiratory distress syndrome (ARDS) was made. Despite maximum high flow oxygen patient continues to desaturate and the patient was started on BiPAP with 100% FiO2 with the improvement of hypoxia. The patient continued on Covid specific therapy including dexamethasone. The patient remained BiPAP dependent with intermittent heated high flow nasal cannula with positive pressure support. On the 15-day of hospitalization, the patient noted to have worsening hypoxia, emergent computed tomography angiogram(CTA) of the chest was done which revealed extensive pneumomediastinum. Esophagogram was obtained and esophageal rupture was ruled out. The patient was treated conservatively and monitored for any further complications. On day 43 patient was discharged on 2liter nasal cannula oxygen. Spontaneous pneumomediastinum (SPM) is a rare clinical entity. SPM occurs when the air leak through the small alveolar ruptures into the surrounding bronchovascular sheath. SPM also could result from air leaks from the esophageal or endobronchial rupture. The exact mechanism is unknown but the proposed mechanism is likely via the differential pressure gradient that develops between the Alveoli and lung interstitium. Barotrauma from mechanical ventilation accounts for one-third of the cases of pneumomediastinum. In our case patient was not on mechanical ventilation and esophageal rupture was ruled out by esophagogram, so we believe it is a spontaneous pneumomediastinum. We believe prolonged positive pressure ventilation could lead to rupture of the alveoli in COVID-19 pneumonia, leading to spontaneous pneumomediastinum.
Worms get the munchies: the endocannabinoid AEA induces hedonic amplification in C. elegans by modulating the activity of the AWC chemosensory neuron.

Abstract The mammalian endocannabinoid system, comprised of the endocannabinoids AEA (N-arachidonoyl-ethanolamine) and 2-AG (2-Arachidonoylglycerol), their receptors, CB1 and CB2, and their metabolic enzymes, is believed to integrate internal energy state and external food cues to modulate feeding. For example, cannabinoids can increase preference for more palatable, calorically dense food: a response called hedonic amplification, colloquially known as “the munchies.” In mammals, cannabinoids can increase sensitivity to odors and sweet tastes, which may underlie amplification. We use C. elegans, an omnivorous bacterivore, as a model in which to investigate the neurophysiology of hedonic amplification. We found that exposure to AEA increases the worms’ preference for strongly preferred (more palatable) bacteria over weakly preferred (less palatable) bacteria, mimicking hedonic amplification in mammals. Furthermore, AEA acts bidirectionally, increasing consumption of strongly preferred bacteria while decreasing consumption of weakly preferred bacteria. We also found that deletion of the putative CB1 homolog, npr-19, eliminates hedonic amplification, which can be rescued by expression of wild type npr-19 or human CB1, establishing a humanized worm for cannabinoid signaling studies. Deletion of the olfactory neuron AWC, which directs chemotaxis to food, abolishes hedonic amplification. Consistent with this finding, calcium imaging revealed that AEA bidirectionally modulates AWC activity, increasing its responses to strongly preferred food and decreasing its response for weakly preferred food. In a GFP expression analysis, we found that npr-19 is expressed in approximately 21 neuron classes but, surprisingly, not in AWC. Although AEA’s effect could be mediated by NPR-19-expressing neurons presynaptic to AWC, nearly complete elimination of fast synaptic transmission, via the mutation unc-13(e51), had no effect on modulation. Instead, it appears that AEA modulates AWC by activating one or more npr-19-expressing neurons that release a diffusible neuromodulator to which AWC is sensitive.
Strings and Cables

In the previous chapters, controllers were designed for mechanical systems that are modeled by nonlinear ODEs. For the remainder of this book, we will focus our attention on the development of control algorithms for mechanical systems that are assumed to be modeled by PDEs.
Some Principles Underlying the Cognitive Approach to Instructional Design

I n the generation since the birth of the instructional design field, our understanding of the basic psychological mechanisms of memory, perception, learning, and problem solving has seen a great deal of development. Corresponding progress in our understanding of the psychology of instruction (or, if you prefer, designof learning environments) has led to important newdefinitionsof principles of instructional design. For those familiar with the behavioral approach, this chapterwill reviewwhat you already know and show how the cognitive approach differs. For those who have never had a formal study of the assumptions underlying the behavioral approach, this chapter will provide you with a theoretical understanding of the approach you probably have been using to date. Important additional principles are included in the chapters in Part Three. However, a full discussion of the psychology of learning and instruction is beyond the scope of this chapter and of this handbook. If you are interested in pursuing the subject matter further, references to sources from which this chapter is drawn are provided. We do not mean to imply a disjunctive contrast between the behavioral and the cognitive approach, nor do we mean to imply that behavioral principles are obsolete—only that the cognitive approach often adds prescriptive utility to
Brief, repeated exposure to substrates down‐regulates dopamine transporter function in Xenopus oocytes in vitro and rat dorsal striatum in vivo

In heterologous expression systems, dopamine transporter (DAT) cell-surface localization is reduced after relatively prolonged exposure to d-amphetamine (AMPH) or dopamine (DA), suggesting a role for substrate-mediated regulation of transporter function. Here, we investigated whether brief, repeated periods of substrate exposure modulated transporter function, first, in an in vitro model system and, second, in intact rat brain. In human DAT-expressing Xenopus laevis oocytes, repeated exposure to low micromolar concentrations of DA, AMPH or tyramine markedly reduced transport-mediated currents. This functional down-regulation was attenuated by inclusion of a protein kinase C (PKC) inhibitor and probably reflects DAT redistribution, as cell-surface [3H]WIN 35 428 binding was significantly lower following DA exposure. High-speed chronoamperometry was used to measure clearance of exogenously applied DA in dorsal striatum (STR) and nucleus accumbens (NAc) of anesthetized rats. In STR, frequent (every 2 min) applications of DA altered DA clearance parameters in a manner consistent with profound down-regulation of DAT function. Similar changes were not observed in NAc or after repeated vehicle (ascorbic acid) application. Together, our results suggest that brief, repeated periods of substrate exposure lead to rapid down-regulation of DAT activity and that this type of regulation can occur in vivo in STR, but not NAc.
A Case Study of Maternal Response to the Implied Antepartum Diagnosis of Inevitable Labor Dystocia

Two pregnant women, one obese and one of extremely small stature, received antepartum recommendations from their health care providers to schedule cesarean births. In response, both women sought providers who would support their desire to attempt vaginal birth. The women's perspectives on their birth experiences along with the pertinent medical record data from their pregnancies and births provide a reminder about the inherent normalcy of birth amid the current culture of interventive obstetrical practices.
Mollified zone diagrams and their computation

The notion of the zone diagram of a finite set of points in the Euclidean plane is an interesting and rich variation of the classical Voronoi diagram, introduced by Asano, Matousek, and Tokuyama [1]. In this paper, we define mollified versions of zone diagram named territory diagram and maximal territory diagram. A zone diagram is a particular maximal territory diagram satisfying a sharp dominance property. The proof of existence of maximal territory diagrams depends on less restrictive initial conditions and is established via Zorn's lemma in contrast to the use of fixed-point theory in proving the existence of the zone diagram. Our proof of existence relies on a characterization which allows embedding any territory diagram into a maximal one. Our analysis of the structure of maximal territory diagrams is based on the introduction of a pair of dual concepts we call safe zone and forbidden zone. These in turn give rise to computational algorithms for the approximation of maximal territory diagrams. Maximal territory diagrams offer their own interesting theoretical and computational challenges, as well as insights into the structure of zone diagrams. This paper extends and updates previous work presented in [4].
Using value queries in combinatorial auctions

Combinatorial auctions, where bidders can bid on bundles of items, are known to be desirable auction mechanisms for selling items that are complementary and/or substitutable. However, there are 2k --1 bundles, and each agent may need to bid on all of them to fully express its preferences. We address this by showing how them auctioneer can recommend to the agents incrementally which bundles to bid on so that they need to only place a small fraction of all possible bids. These algorithms impose a great computational burden on the auctioneer; we show how to speed them up dramatically. We also present an optimal elicitor, which is intractable but may be the basis for future algorithms. Finally, we introduce the notion of a universal revelation reducer, demonstrate a randomized one, and prove that no deterministic one exists.The full paper is available in draft form at http://www.cs.cmu.edu/ sandholm/using_value_queries.pdf.
Investigation of Variation and Uncertainty in Six-Sigma

Six Sigma is a widely used moniker to represent a set of design and manufacturing techniques, the aggregate of which should effectively improve quality and lower cost. Six Sigma implies that six standard deviations of performance should be maintained between the performance mean and the closest specification limit. When multiple performance attributes must be satisfied, aggregation techniques may be applied for evaluation and optimization. This paper evaluates two common aggregation techniques, the multi-process capability index and the process desirability index, and investigates their appropriateness relative to variation and uncertainty. These methods are applied to a data set for DVD manufacturing generated according to a Central Composite Design for 6 processing variables and 8 quality attributes. The results indicate that both indices may lead to erroneous design and manufacturing decisions with poor estimation of quality and cost.Copyright © 2002 by ASME
Benjamin's Angel of History and the Work of Mourning in Ethical Remembrance: Understanding the Effect of W.G. Sebald's Novels in the Classroom

The paper develops a conceptual framework for understanding the work of ethical remembrance in the classroom. Using David Hansen’s recent example of using Sebald’s novels in his classroom to do the work or remembrance, the paper argues that the effect of Sebald’s novels is best understood using Walter Benjamin’s figure of the angel of history. That figure indicates a view of history that goes beyond the progression of everyday time, to one called remembrance. The paper suggests that the work of mourning effects such remembrance, but simultaneously points to hope through the emergence of weak messianic power.
Unified Theory of Stimulated Raman Scattering and Two-Plasmon Decay in Inhomogeneous Plasmas: High Frequency Hybrid Instability.

The theories of stimulated Raman scattering (SRS) and two-plasmon decay (2{omega}{sub {ital pe}}) in inhomogeneous plasmas have been unified by adopting a powerful new variational approach. We call this technique the minimum pump strength principle (MPSP), and the unified process, the high frequency hybrid instability (HFHI). The growth rate and frequency shift of the most unstable mode of HFHI are shown to match smoothly onto the two known limiting cases: 2{omega}{sub {ital pe}} at large {ital k}, and SRS backscattering as {ital k} goes to zero. The effectiveness of this method has allowed the generalization of the density inhomogeneity treated from a constant gradient to any positive-integer power law. Potential experimental signatures of HFHI modes are described. {copyright} {ital 1995} {ital The} {ital American} {ital Physical} {ital Society}.
Hemorrhagic myocardial infarction associated with aortocoronary bypass revascularization

Experimentally, hemorrhage and extension of myocardial infarction occur commonly when there is reperfusion after coronary artery occlusion. To investigate this hazard in a clinical setting, we compared the histopathologic picture of myocardial infarction in 44 patients who had undergone aortocoronary bypass: 14 (Group I) had myocardial infarction that predated aortocoronary bypass by 1 to 7 days; 13 (Group II) had infarction 1 to 14 days after the surgery; and 17 (Group III) had infarction 15 to 90 days postoperatively. All 44 patients had two or more coronary arteries with luminal narrowing of more than 75 per cent and patent vein grafts to arteries supplying areas of infarction. Hemorrhagic infarcts were present in 57 per cent of patients (eight of 14) in group I and 38 per cent of patients (five of 13) in Group II, contrasting with 6 per cent of patients (one of 17) in Group III (P < 0.005 and P < 0.05, respectively). In hemorrhagic infarcts, the extravasated blood formed irregular intramural dissecting tracts beyond the area of infarction, and foci of myocardial necrosis were present in the border zones. Infarcts affected more than 50 per cent of the left ventricular muscle in 64 per cent of cases of hemorrhagic infarction and in 13 per cent of cases of nonhemorrhagic infarction (P < 0.05). The prevalence of hemorrhagic infarction after revascularization may account for the high mortality of evolving and perioperative myocardial infarction associated with aortocoronary bypass, and this finding militates against wholesale immediate revascularization in patients who have uncomplicated myocardial infarction.
The old left revisited: Machine technology as “social myth”

Recent perspectives on social movements have focused on the importance of organization, who participates, and the process by which they develop their social base. This paper uses the Old Left as an example of how symbols can serve as a mobilizing force for a social movement. The paper attempts to analyze the use of symbols in the Old Left by grafting Leo Marx's apolitical formulation of cultural antimonies (the machine and the garden) on George Sorel's political conceptualization of “social myths.” The paper examines how the machine operated as a “social myth” for the Old Left. The paper traces how the Old Left used the machine and machine power to dramatize the irresistible dynamism of a new industrial order.
Yersinia pestis Activates Both IL-1β and IL-1 Receptor Antagonist to Modulate Lung Inflammation during Pneumonic Plague

Pneumonic plague is the most rapid and lethal form of Yersinia pestis infection. Increasing evidence suggests that Y. pestis employs multiple levels of innate immune evasion and/or suppression to produce an early “pre-inflammatory” phase of pulmonary infection, after which the disease is highly inflammatory in the lung and 100% fatal. In this study, we show that IL-1β/IL-18 cytokine activation occurs early after bacteria enter the lung, and this activation eventually contributes to pulmonary inflammation and pathology during the later stages of infection. However, the inflammatory effects of IL-1β/IL-1-receptor ligation are not observed during this first stage of pneumonic plague. We show that Y. pestis also activates the induction of IL-1 receptor antagonist (IL-1RA), and this activation likely contributes to the ability of Y. pestis to establish the initial pre-inflammatory phase of disease.
The Measurement of Acceleration With a Vacuum Tube

Acceleration can be measured with a vacuum tube conisisting of a fixed cathode and two plates, one on each side of the cathode. The plates arc mounted elastically to deflect in response to acceleration normal to their plane. Displacement of a plate alters the electron current delivered from the cathode to that plate. A tube of this type is described which has a natural frequency of about 800 cycles per second, a flat response for sinusoidal accelerations up to 200 cycles per second, and a linear range of 150g. The output at accelerations of 10g is sufficient to drive a high frequency recording galvanometer directly, without the complications of an amplifier. The pricipal disadvantages of the tube are an unpredictable ``zero drift'' and a ``zero shift,'' following impacts of very short duration.
Peroxisome proliferator activated receptor-γ (PPARγ) represses thyroid hormone signaling in growth plate chondrocytes

Peroxisome proliferator activated receptors (PPARs) are DNA-binding nuclear hormone receptors that are upregulated in response to high fat diets. PPARs are structurally related to the type II nuclear receptors, including the thyroid hormone receptors (TRs). To investigate if PPARs modulate TR-mediated terminal differentiation of growth plate chondrocytes, primary cultures of epiphyseal chondrocytes transiently transfected with TRalpha and PPARgamma expression vectors were treated with the PPAR ligands ciglitazone or troglitazone. Forced overexpression of PPARgamma decreased TRalpha1-mediated transcriptional activity and suppressed T3-induced increases in alkaline phosphatase activity and type X collagen expression. Similar effects were observed when the cells were treated with the PPARgamma activator ciglitazone or troglitazone. Overexpression of retinoid X receptor-alpha (RXRalpha) partially restored not only the inhibition of transcriptional activation by PPARgamma but also T3-induced hypertrophic differentiation. These data demonstrate that activation of PPARgamma signaling by either addition of PPARgamma ligands or overexpression of PPARgamma in growth plate chondrocytes inhibits TR-mediated gene transcription and inhibits the biological effects of thyroid hormone on terminal differentiation. The molecular mechanism involved in this inhibition appears to be competition between PPARgamma and TRalpha for limiting amounts of the heterodimeric partner RXR.
Evaporation-enhanced impedance sensing for highly-sensitive differentiation of dsDNA from ssDNA

In this paper, we adopt a radically different approach to beat the diffusion limit through time-dependent evaporation of microliter-sized droplets (containing DNA molecules) pinned onto an array of electroplated nickel electrodes, and thereby achieve highly sensitive, statistically-robust, label-free, non-faradaic impedance-based differentiation of ssDNA vs. dsDNA at femtomolar (~fM) concentration. The proposed approach is ideally suited for integration in a portable, array format, and could be used in real-time point-of-care applications for which highly sensitive, yet selective detection of DNA hybridization is desired.
Serum and Tissue Homocysteine Analysis by HPLC

Abstract A simplified HPLC method for analysis of homocysteine based on a two step procedure is described. In the first step, a simultaneous reduction, and derivatization of this amino acid in the presence of serum proteins takes place. In the second step proteins are removed by acid precipitation followed by an HPLC with fluorescence detection. The method is rapid and utilizes small volumes of serum. Both serum and tissues were analyzed by this method. The reference range for serum is 4–16 μmol/L, n=34. Patients with renal failure are shown to have elevated mean serum levels (18.5 μmol/L, n=20) compared to normal individuals (10.1 μmol/L, n=34).
Anisotropy Of The Lateral Scattering Of Linearly Polarized Light

This study demonstrates how lateral scattering is affected by particle distribution and by optical depth, in the direction of the incident linearly polarized light. Previous publications have linked only scattering particle size to lateral scattering anisotropy. This presentation indicates that the anisotropy apparently disappears for optical depths of approximately 10 and greater if the scattering is produced by uniformly sized particles. In addition, for at least one particle distribution (latex paint in water), this anisotropy does not appear regardless of the optical depth.
Combined lectin-affinity and metal-interaction chromatography for the separation of glycophorins by high-performance liquid chromatography

Human erythrocyte sialoglycoproteins, or glycophorins, were chromatographed by lectin-affinity and metal-interaction chromatography on high-performance liquid chromatographic columns. Glycophorins A, B and C were separated from other proteins and from glycophorin E by using a column containing wheat germ agglutinin, immobilized on a microparticulate silica support. The glycophorins were adsorbed on the lectin column from a mobile phase containing 0.25 M sodium chloride and recovered by stepwise desorption with 0.2 M N-acetylglucosamine solution. Glycophorins A, B and C were separated into the individual components on a silica-bound iminodiacetic acid stationary phase in the copper(II) chelate form. The separation of the glycophorins by metal-interaction chromatography was accomplished by decreasing salt gradient elution. Retention times and resolution of the individual glycophorins were sensitive to the initial sodium chloride concentration and the pH of the eluent. Addition of methanol to the eluent increased the resolution. The effects of linear, decreasing gradients of pH and methanol in 25 mM phosphate buffer on the resolution of glycophorins were also investigated. In both types of chromatography the mobile phases contained 0.05% (w/v) sodium dodecyl sulfate. With octylglycoside or CHAPS in the eluent glycophorins A and C could not be eluted. Sodium dodecyl sulfate polyacrylamide gel electrophoresis was used to analyze all the chromatographic results.
Chronic postnatal hypoxia increases the numbers of cortical neurons

Premature infants have been shown to undergo prolonged periods of sublethal hypoxia. There is considerable evidence to link these hypoxic events with neurodevelopmental disorders. As an animal model for this clinical problem, rats were raised from the third day of life in a chamber where the O2 level was 9.5%. After 30 days of hypoxia the rats were sacrificed and their brains processed for determination of the number of cortical neurons. This work was performed to test the hypothesis that chronic hypoxia would result in increased cortical cell death. The hypoxic rats had lower body and brain weights as well as decreased cortical volumes. However, hypoxic rats had increased neuronal density and significantly more cortical neurons than controls (P < 0.05). The results of this study suggest that chronic sublethal hypoxia may lead to reduction in the amount of programmed cell death in the developing neocortex.
Differential effects on phrenic output of two dopamine agonists, apomorphine and bromocriptine

Abstract Effects of dopamine agonists upon phrenic output were studied in decerebrate, vagotomized, paralyzed, carotid-body denervated dogs. Intravenous administration of dopamine was without effect in these dogs. Apomorphine (APO) increased phrenic minute activity while bromocriptine (BRO) decreased phrenic minute activity following intravenous injection at doses of 100 μg/kg for each drug. BRO-induced decreases in phrenic minute activity were associated with decreases in phrenic amplitude; burst frequency remained unchanged. Conversely, APO-induced increases in phrenic minute activity resulted from significant increases in both frequency and amplitude. Both APO and BRO significantly prolonged inspiratory duration and shortened expiratory duration. Responses to APO and BRO were abolished with haloperidol. These results confirm previous evidence for the existence of dopaminergic receptors within the central nervous system, which are inaccessible to exogenous dopamine, and which can alter timing as well as amplitude characteristics of the integrated phrenic neurogram. Both excitation and inhibition of phrenic activity following administration of APO and BRO are mediated by mechanisms within or below the caudal brainstem.
A Study of the Mechanical Behavior of Polyimides

The mechanical properties of four different polyimide samples are measured. H-film, poly(N,N'-( p,p'-oxydiphenylene)pyromellitimide), shows no softening phenomena below 500°C. The three other polyimides exhibit a definite softening at elevated temperatures. All of the samples investigated show evidence of chemical reaction and eventual deRrada tion taking place above 400°C.While x-ray techniques show H-film to be slightly crystalline, the other polyimides display typical amorphous scattering patterns.Annealing raises the softening temperature and induces crystallinity in one of the samples.Factors such as the purity of starting materials and the complete conversion to polyimide linkage must be considered when comparing the mechanical properties of these various polyimides.
Evaluating the effect of ambient particulate pollution on DNA methylation in Alaskan sled dogs: Potential applications for a sentinel model of human health

Abstract Background Exposure to ambient particulate matter (PM) is known to be associated with increased morbidity and mortality in human populations. During the winter months in Fairbanks, Alaska, severe temperature inversions lead to elevated concentrations of ambient PM smaller than 2.5 μm (PM 2.5 ). Sled dogs represent an easily accessible environmentally exposed population that may yield findings informative for human health risk assessment. Objectives In this pilot study, we evaluated whether ambient PM was associated with markers of global methylation in sled dogs. Methods Kennels were strategically recruited to provide a wide PM 2.5 exposure gradient for the Fairbanks area. Continuous monitoring of ambient PM 2.5 was conducted at each kennel during the winter of 2012/13 using a DustTrak 8530. Dogs received a physical examination and assessment of standard hematology and clinical chemistries. Global methylation was determined using the LUminometric Methylation Assay (LUMA) and 5-Methycytosine (5-mC) quantification. Results Three sled dog kennels (n ~ 30 dogs/kennel) were evaluated and sampled. The average PM 2.5 concentrations measured for kennels A, B, and C were 90 μg/m 3 , 48 μg/m 3 , 16 μg/m 3 (p Conclusions In this study we evaluated global methylation using LUMA and 5-mC and found no differences between kennels, though exposure to ambient PM 2.5 was significantly different between kennels. As more information becomes available regarding immunologically-related canine genes and functionally active promoter subunits, the utility of this surrogate could increase.
The mesh superceded

Two dimensional interconnection schemes have some inherent advantages because of their linear area and constant wire-lengths. The nearest-neighbor mesh is such a topology that has enjoyed a widespread acceptance. We investigate a family of bus-based topologies called the doble-lattice-meshes, and propose a variation to improve their properties. We show that the bus-based topologies perform better than the mesh for a variety of communicaion structures. In particular, when global communication is needed, they provide larger effective bandwidth, and when localized communication is permissible, they provide largest neighborhoods for a given communication capacity.
In vitro activity of DNA gyrase inhibitors, singly and in combination, against Mycobacterium avium complex.

Abstract The in vitro activities of the DNA gyrase inhibitors ciprofloxacin, coumermycin, and novobiocin against 31 clinical isolates of Mycobacterium avium complex were studied using a microdilution technique. Minimal inhibitory concentrations (MICs) were determined in 4 days using Middlebrook 7H9 broth, and minimal bactericidal concentrations (MBCs) were determined by subculturing to Middlebrook 7H10 agar. MICs were: ciprofloxacin, 0.5–>16 (mean, 4.1) μg/ml; novobiocin, 4–>128 (mean, 54.7) μg/ml; and coumermycin, 2–>16 (mean, 17.5) μg/ml. MBCs were usually more than two dilution steps higher than MICs. Checkerboard studies failed to reveal synergistic or antagonistic inhibitory activity of DNA gyrase-A and DNA gyrase-B inhibitors in vitro.
Concept Evaluation of Intersection Decision Support (IDS) System Interfaces to Support Drivers' Gap Acceptance Decisions at Rural Stop-Controlled Intersections

Abstract Rural stop-controlled intersections pose a crash risk for drivers turning or crossing the intersection from the minor road. In particular, elderly drivers are at the highest risk of a collision in this situation. Errors made during gap detection, perception and acceptance are the main factors that influence crashes at this type of intersection. This study investigated young (20–40 years) and old (55–75 years) drivers’ gap acceptance performance in simulated day and night driving conditions in a Baseline condition (STOP sign only) and four intersection decision support (IDS) conditions. The four IDS conditions were initial infrastructure-based design concepts that provided varying levels of dynamic information about traffic conditions on the major road to crossing minor-road drivers. Signs that provided detailed gap information (i.e., time-to-arrival values, warning levels for gaps) as well as advisory information about unsafe conditions resulted in the best performance among old and young drivers in comparison to signs that did not provide specific gap-related information (i.e., detected vehicles approaching, but not size of gap or safety of gap). Comprehension, acceptance and usability ratings of the IDS signs were also highest for signs providing detailed gap and advisory information on the same sign. Recommendations for further design and development of the IDS system interface based on driver performance and acceptance of the technology is discussed.
Lower bounds for heights in cyclotomic extensions

Abstract We show that the height of a nonzero algebraic number α that lies in an abelian extension of the rationals and is not a root of unity must satisfy h ( α ) > 0.155097 .
LONG-TERM TRENDS IN MIGRATORY BEHAVIOR IN A DEVELOPING COUNTRY: THE CASE OF MEXICO

Comparable lifetime migration relationships are estimated for Mexico for 1950, 1960, and 1970. Moreover, migration flows from each state to every other state are separately examined for each year. A number of significant changes over time are evident in the responsiveness of Mexican internal migrants to various socioeconomic stimuli, and appreciable differences are also evident across space. Moreover, a threshold is observed such that up to about 340 miles higher origin earnings deter migration, but beyond this distance higher earnings actually encourage migration.
Two-Layer Tidal Circulation in a Frictional, Rotating Basin

The three-dimensional tidal circulation in an elongated basin of arbitrary depth is described with a coupled barotropic and baroclinic two-layer model on the f plane. As long as friction is not dominant, near-standing waves are present on the interface as well as on the surface. The surface pattern is principally determined by the product of the tidal barotropic wavenumber by the basin length. The interface deformation is determined by a baroclinic equivalent, usually a much larger number. As a result, the shape of the interface is characterized by horizontally smaller features than the surface. If the product of the tidal baroclinic wavenumber by the basin width is greater than one, both lateral and axial modes can be excited at the interface. If these modes are near resonant, large internal tides can be forced directly by the co-oscillating surface tide at the basin entrance. The amplitude and phase of the baroclinic component are sensitive functions of the density anomaly and the interface depth. As a result, the phase and amplitude of the interface vary by large amounts with comparatively small changes in those parameters. The model behavior is qualitatively consistent with observations in fjords and straits.
The Infrared Radiance of the Earth Between 5 and 20 Microns

A knowledge of both the average infrared radiance of the earth and the variations from this average is required for the design of earth viewing satellite born infrared sensors. For any sensor attempting to view an object while the earth is in its field of view, the radiance of the earth, including its atmosphere, presents a significant background. This background may seriously interfere with the sensing of the object. We present here an analysis of infrared earth radiance data obtained by the NIMBUS III satellite.
Analog synthesis from behavioral descriptions

An automated synthesis system is described for the design of high-level analog circuits and systems. A circuit is specified by its dynamic behavior-described using a class of time-differential equations or state-space equations. The desired performance requirements and the imposed constraints are specified. A synthesis procedure is described to perform structural synthesis of a circuit in terms of analog functions which result in dynamic behavior equivalent to the specified equations. The design system then proceeds in a hierarchical top-down fashion to develop the circuits and the layouts for the individual functional blocks in order to achieve the desired performance. This culminates in an integrated circuit layout whose behavior and performance correspond to input specifications. >
The Tradeoff Between Compensation and Incentives in Executive Stock Options

Because stock options have a dual role as both compensation and incentives, a portion of option value represents compensation and a portion represents incentives. We develop a model that measures the tradeoff between the compensation and incentive values of options. Empirical estimates over a 14-year period show that the median option contains $1.08 of incentives for every $1.00 of compensation and that option compensation is around 30% of total compensation. We also find that firms that use options more as a compensation device use fewer options and reduce other cash payments suggesting a resourceful and not abusive use of options.