cssi/SciSciGPT-SciSciNet huggingface dataset:
Computing characteristic classes of subschemes of smooth toric varieties

Abstract Let X Σ be a smooth complete toric variety defined by a fan Σ and let V = V ( I ) be a subscheme of X Σ defined by an ideal I homogeneous with respect to the grading on the total coordinate ring of X Σ . We show a new expression for the Segre class s ( V , X Σ ) in terms of the projective degrees of a rational map specified by the generators of I when each generator corresponds to a numerically effective (nef) divisor. Restricting to the case where X Σ is a smooth projective toric variety and dehomogenizing the total homogeneous coordinate ring of X Σ via a dehomogenizing ideal we also give an expression for the projective degrees of this rational map in terms of the dimension of an explicit quotient ring. Under an additional technical assumption we construct what we call a general dehomogenizing ideal and apply this construction to give effective algorithms to compute the Segre class s ( V , X Σ ) , the Chern–Schwartz–MacPherson class c S M ( V ) and the topological Euler characteristic χ ( V ) of V. These algorithms can, in particular, be used for subschemes of any product of projective spaces P n 1 × ⋯ × P n j or for subschemes of many other projective toric varieties. Running time bounds for several of the algorithms are given and the algorithms are tested on a variety of examples. In all applicable cases our algorithms to compute these characteristic classes are found to offer significantly increased performance over other known algorithms.
The politics of global public health in fragile states and ungoverned territories

The reasons for global health crises and how the world responds to them have dramatically changed over the last half century. Increasingly, natural disasters result in failure of public health and security systems leading to preventable conflict, unconventional war and unprecedented population migration. While scientific expertise exists to mitigate these failures in fragile states and ungoverned territories, inactions are mired by the lack of political will, international legal mandates, and capacity to strategically monitor multidisciplinary public health indicator failures.
Efficient Parameter Estimation for Multivariate Jump-Diffusions

This paper develops unbiased Monte Carlo estimators of the transition and marginal densities of a multivariate jump-diffusion process. The drift, volatility, jump intensity, and jump magnitude are allowed to be state-dependent and non-affine. It is not necessary to diagonalize the volatility matrix. Our density estimators facilitate the parametric estimation of multivariate jump-diffusion models based on discretely observed data. The parameter estimators we propose have the same asymptotic behavior as maximum likelihood estimators under mild conditions. Our approach is found to be highly accurate and computationally efficient in a numerical case study of practical relevance.
A Reexamination of the Mechanism of the Semiannual Oscillation in the Southern Hemisphere

The local pressure changes associated with the twice-annual contraction/intensification and expansion/weakening of the circumpolar trough of low pressure around Antarctica, termed the semiannual oscillation (SAO), was the dominant signal in the annual cycle at mid and high southern latitudes before 1979. The mechanism, as shown by Van Loon (1967), arises from diVerent response to the surface heat budget over the polar continent and the midlatitude ocean. It has subsequently been shown that in most years since 1979 the SAO has weakened considerably. Evidence is presented here from surface temperature data, 500 mb temperatures from a station pair and zonal mean 500 mb temperatures from the NCAR/NCEP reanalyses to show that a warming trend since 1979 has not been evenly distributed through the year at each latitude. Thus an anomalous change in the temperature gradient between 50°S and 65°S, with peaks in roughly May and November, has modulated the mechanism that produces the SAO, with its peaks in March and September. Consequently, the magnitude of the SAO has decreased in the more recent period.
Atomic Origins of the Self-Healing Function in Cement–Polymer Composites

Motivated by recent advances in self-healing cement and epoxy polymer composites, we present a combined ab initio molecular dynamics and sum frequency generation (SFG) vibrational spectroscopy study of a calcium–silicate–hydrate/polymer interface. On stable, low-defect surfaces, the polymer only weakly adheres through coordination and hydrogen bonding interactions and can be easily mobilized toward defected surfaces. Conversely, on fractured surfaces, the polymer strongly anchors through ionic Ca–O bonds resulting from the deprotonation of polymer hydroxyl groups. In addition, polymer S–S groups are turned away from the cement–polymer interface, allowing for the self-healing function within the polymer. The overall elasticity and healing properties of these composites stem from a flexible hydrogen bonding network that can readily adapt to surface morphology. The theoretical vibrational signals associated with the proposed cement–polymer interfacial chemistry were confirmed experimentally by SFG vibrationa...
Methylation-wide association analysis reveals AIM2, DGUOK, GNAI3, and ST14 genes as potential contributors to the Alzheimer's disease pathogenesis

Introduction: Alzheimer's disease (AD) is a progressive complex neurodegenerative disorder with devastating impact on cognitive abilities. It is among the top 10 leading causes of death in the United States with no curative medications. Exploring genetic and non-genetic contributors to AD development is, therefore, of great importance. Methods: We investigated the AD-associated epigenetic changes by combing results from publicly available genome-wide association analyses and a large-scale methylation quantitative trait loci study. Results: Probes mapped to 133 genes were associated with AD with < 2.50E-06. Of these, four genes (i.e., GNAI3, AIM2, DGUOK and ST14) provided stronger evidence of possible role in AD pathogenesis as they were also significantly associated with AD in previous expression quantitative trait loci analyses and/or mouse model studies. Discussion: Although the identified associations do not prove any definitive causal relationships with AD, they provide a list of prioritized genes for follow-up functional studies.
Wikipedia and the New Web

For most people in the Western world, Wikipedia has become the first – and often last – stop for information about pop culture, science, medicine, history, and just about anything else. Donating to the Wikimedia Foundation, the nonprofit that runs Wikipedia and its sister projects, has become mainstream. News stories about Wikipedia and its editors are no longer focusing on the oddity of a collection of geeks trying to write an encyclopedia. Instead, that people would choose to do so is not even questioned, and the content they have produced and the complex political system they engage in are scrutinized by the mainstream.
Java version 5 for introductory courses

This tutorial introduces features contained in the release of Java 2 Standard Edition (J2SE) version 5.0. It will include an overview of many of the features of interest to educators and explanations of why it is in our best interest to be proactively using this new release of the language in first-year courses.
Combined FISH and immunofluorescent staining methods to co-localize proteins and mRNA in neurons and brain tissue

Combining multicolor fluorescent in situ hybridization (FISH) and immunofluorescent staining (IFS) presents a powerful method for visualizing the spatial relationship between mRNA and proteins in different neural compartments. Although seemingly straightforward, the combination of IFS/FISH and quantitative co-localization analysis of mRNA and proteins can be difficult to perform successfully, often generating variable results. Here we describe a combined method of multicolor IFS and FISH in concert with two-dimensional (2D) and three-dimensional (3D) co-localization analysis for determining the expression of individual molecules in rat neurons and brain sections. Using this approach, we have analyzed interactions of the Huntington's disease protein huntingtin with select proteins and mRNA.
Ancestral Pueblo trails and the cultural landscape of the Pajarito Plateau, New Mexico

Although trails are widely recognized as an important element in the shaping of social and economic space, poor preservation and complex interpretations have meant that they are rarely the subject of systematic archaeological analysis. Ancestral Pueblo trails of New Mexico's Pajarito Plateau, in contrast, are both well-preserved and easily identified, providing an opportunity to study patterns of movement through the landscape during the 500 years prior to Spanish colonization. This study discusses the broader issues of analysing archaeological trails with specific reference to the Pajarito case.
Identification of breast cancer by differences in urinary iodine

2150 Introduction: Iodine is involved metabolically in normal, nursing, and neoplastic breast tissues. Our objective was to evaluate differences in urinary iodine levels in women with benign and malignant breast changes. Methods: Ninety-eight women with a median age of 47 years (range 15-87) presenting with benign or malignant breast diagnoses to the university breast center participated in this study. Women with a history of hyper/ hypothyroidism were excluded. Urine specimens were collected following informed consent. Urine was quantified by chromatography/anion exchange resin. Values are reported as micrograms (mcg) iodine or milligrams (mg) bromide per liter by ion selective electrode assay. A t-test was used to compare means. Results: Our final cohort included 20 women with cancer (DCIS =6; invasive cancer=14), 20 women who were smokers and 42 who were post menopausal. A significant difference in iodine excretion between women with cancer (105 mcg/l) versus non-cancer (141 mcg/l, p
“Noite de Almirante”: Interracial Love in Machado de Assis’s Nineteenth Century / “Noite de Almirante”: raça e relações amorosas no século XIX de Machado de Assis

Abstract: In the twenty-first century some scholars started revisiting the works of the mulatto Machado de Assis through discussions about his racial identification and posture with regard to race. As a consequence a new range of reading possibilities has been released. The racial identification of the characters, hence, their interpretations, customarily based on an ideal hegemonic white model of society, began to be revised and challenged. Having racial marks attributed to the characters as the starting point while approaching them reveals Machado’s keen eye on the tension involved in the negotiations of spaces in the not always harmonious relations developed in the extremely mixed-race nineteenth-century Brazilian society. This essay resorts to the short story “Noite de almirante,” hitherto excluded from this perspective, as a case study to demonstrate the potential of such a reading. Keywords: race; Afro-Brazilian literature; Machado de Assis. Resumo: Com o advento do seculo XXI, uma parcela dos estudiosos da obra do mulato Machado de Assis iniciou um processo de arejamento das discussoes sobre sua identificacao racial e postura diante da questao da raca. Um novo leque de possibilidades de leitura foi aberto e a identificacao racial das personagens, e por conseguinte suas interpretacoes, tao costumeiramente alicercadas num modelo de sociedade ideal e hegemonicamente branca, comeca a ser revista. Uma leitura das personagens machadianas feita a partir das marcas raciais a elas atribuidas, revela um olhar ainda mais agucado do Bruxo sobre a tensao envolvida nas negociacoes dos espacos nas nem sempre harmoniosas relacoes desenvolvidas na extremamente mestica sociedade brasileira do seculo XIX. Aqui, o conto “Noite de almirante,” ate o momento excluido dessa perspectiva, servira de caso de estudo para demonstrar o potencial de tal leitura. Palavras-chave: raca; literatura afro-brasileira; Machado de Assis.
Management of Splenic Abscess

The surgical management of splenic abscess is determined by patient factors, anatomy, and pathology. The roles of splenectomy and percutaneous drainage with respect to these factors are presented in a clinical algorithm for patients in whom splenic abscess is evident on imaging.
Structure of tendon organs in fishes of the genus Polymixia

Modified branchiostegal rays 1 through 3 support the proximal end of the paired hyoid barbels in the beardfish (Beryciformes: Polymixiidae). The polymixiid barbel is unusual in that it has an unique intrinsic muscular system. Using silver impregnation and electron microscopic techniques, unencapsulated, free nerve endings were located within the tendon of the third modified branchiostegal ray. Branchiostegal rays 1 and 2 do not have any free nerve endings associated with their tendons, however. It is suggested that the free nerve endings are proprioceptors acting as stretch-sensitive mechanoreceptors, and that branchiostegal ray 3 acts as part of a sensory apparatus for monitoring the positional state of the barbel. Branchiostegal rays 1 and 2 merely provide support for the barbel.
Stable values and variable constraints; the sources of behavioral and cultural differences

If all differences in behavior are explainable in terms of universal values pursued under variable constraints, then much ethical theorizing is pointless. A strong presumption in favor of universal values can be established by showing that differences in behavior that were previously thought to be explainable only in terms of differences in values, can in fact be explained in terms of differences in constraints. Eleven such cases are briefly discussed, including cases of differences among racial, religious and other groups in crime, culinary practices and the acceptance of innovation.
Abstract WP398: Impact of a Direct Ambulance-to-CT Stroke Protocol on Race, Sex, and Language Disparities in Stroke Treatment Times

Introduction: Prior studies have documented disparities in key acute stroke care metrics, with women and minorities more likely to have treatment delays and less likely to receive IV tPA. Objective...
Assessing the social cost and benefits of a national requirement establishing antibiotic stewardship programs to prevent Clostridioides difficile infection in US hospitals

Economic evaluations of interventions to prevent healthcare-associated infections in the United States rarely take the societal perspective and thus ignore the potential benefits of morbidity and mortality risk reductions. Using new Department of Health and Human Services guidelines for regulatory impact analysis, we developed a cost-benefit analyses of a national multifaceted, in-hospital Clostridioides difficile infection prevention program (including staffing an antibiotic stewardship program) that incorporated value of statistical life estimates to obtain economic values associated with morbidity and mortality risk reductions. We used a net present value model to assess costs and benefits associated with antibiotic stewardship programs. Model inputs included treatment costs, intervention costs, healthcare-associated Clostridioides difficile infection cases, attributable deaths, and the value of statistical life which was used to estimate the economic value of morbidity and mortality risk reductions. From 2015 to 2020, total net benefits of the intervention to the healthcare system range from $300 million to $7.6 billion when values for morbidity and mortality risk reductions are ignored. Including these values, the net social benefits of the intervention range from $21 billion to $624 billion with the annualized net benefit of $25.5 billion under our most likely outcome scenario. Incorporating the economic value of morbidity and mortality risk reductions in economic evaluations of healthcare-associated infections will significantly increase the benefits resulting from prevention.
Securing Software Ecosystem Architectures: Challenges and Opportunities

We identify the challenges and opportunities for improving the security of software ecosystems and supply chain processes. Every software ecosystem has one or more architectural models that can be visually mapped, communicated, and understood to improve supply chain process security.
Uncertainty Quantification for Ti-7Al Alloy Microstructure with an Inverse Analytical Model (AUQLin)

The present study addresses an inverse problem for observing the microstructural stochasticity given the variations in the macro-scale material properties by developing an analytical uncertainty quantification (UQ) model called AUQLin. The uncertainty in the material property is modeled with the analytical algorithm, and then the uncertainty propagation to the microstructure is solved with an inverse problem that utilizes the transformation of random variables principle. The inverse problem leads to an underdetermined linear system, and thus produces multiple solutions to the statistical features of the microstructure. The final solution is decided by solving an optimization problem which aims to minimize the difference between the computed and experimental statistical parameters of the microstructure. The final result for the computed microstructural uncertainty is found to provide a good match to the experimental microstructure information.
Technical Note: An open source solution for improving TG-263 compliance.

PURPOSE Compliance with TG-263 nomenclature standards can be challenging. We introduce an open source solution to this problem and evaluate its impact on compliance within our institution. MATERIALS/METHODS The TG-236 nomenclature standards were implemented in our clinic in two phases. In phase 1, we deployed TG-263 compliant templates for each disease site. In phase 2, we developed and deployed a script for evaluating compliance which presented errors to the user. After each phase the compliance was recorded. RESULTS Mean compliance errors prior to phase 1 was 31.8% ± 17.4%. Error rates dropped to 8.1% ± 12.2% across phase 1 and dropped further to 2.2% ± 6.9% during the automation system deployed in phase 2. CONCLUSION Both structure templates and automation scripts are very useful for increasing compliance with structure naming standards. Our software solution is made available on GitHub for other institutions to implement.
Genomic Characterization of ERBB2-Driven Biliary Cancer and a Case of Response to Ado-Trastuzumab Emtansine.

PURPOSEBiliary tract cancers (BTCs), which include intrahepatic cholangiocarcinoma (ICC), extrahepatic cholangiocarcinoma (EHC), and gallbladder cancer (GBC), have limited treatment options. We sou...
“What Will I Experience in My College STEM Courses?” An Investigation of Student Predictions about Instructional Practices in Introductory Courses

Undergraduate students in large introductory STEM courses were surveyed at the beginning of the semester about their expectations of how in-class time would be used. It was found that students, par...
Short-pulse laser irradiation of microparticle contamination on reflective optics (Conference Presentation)

This work investigates the interaction of 10-ps and 0.6-ps, 1053-nm laser pulses with ≈40 um-diam microparticles located on the surface of a multilayer dielectric mirror. Resulting morphology was examined as a function of fluence and number of pulses (1–10) for four different particle materials (one metal, one glass, and two polymers). Processes of particle ejection, particle-assisted laser-induced–damage, and damage growth are discussed, all of which occur at fluences less than half of the pristine (not contaminated) laser-induced–damage threshold of the mirror.
IL-4/IL-13 polarization of macrophages enhances Ebola virus glycoprotein-dependent infection.

Background Ebolavirus (EBOV) outbreaks, while sporadic, cause tremendous morbidity and mortality. No therapeutics or vaccines are currently licensed; however, a vaccine has shown promise in clinical trials. A critical step towards development of effective therapeutics is a better understanding of factors that govern host susceptibility to this pathogen. As macrophages are an important cell population targeted during virus replication, we explore the effect of cytokine polarization on macrophage infection. Methods/main findings We utilized a BSL2 EBOV model virus, infectious, recombinant vesicular stomatitis virus encoding EBOV glycoprotein (GP) (rVSV/EBOV GP) in place of its native glycoprotein. Macrophages polarized towards a M2-like anti-inflammatory state by combined IL-4 and IL-13 treatment were more susceptible to rVSV/EBOV GP, but not to wild-type VSV (rVSV/G), suggesting that EBOV GP-dependent entry events were enhanced by these cytokines. Examination of RNA expression of known surface receptors that bind and internalize filoviruses demonstrated that IL-4/IL-13 stimulated expression of the C-type lectin receptor DC-SIGN in human macrophages and addition of the competitive inhibitor mannan abrogated IL-4/IL-13 enhanced infection. Two murine DC-SIGN-like family members, SIGNR3 and SIGNR5, were upregulated by IL-4/IL-13 in murine macrophages, but only SIGNR3 enhanced virus infection in a mannan-inhibited manner, suggesting that murine SIGNR3 plays a similar role to human DC-SIGN. In vivo IL-4/IL-13 administration significantly increased virus-mediated mortality in a mouse model and transfer of ex vivo IL-4/IL-13-treated murine peritoneal macrophages into the peritoneal cavity of mice enhanced pathogenesis. Significance These studies highlight the ability of macrophage polarization to influence EBOV GP-dependent virus replication in vivo and ex vivo, with M2a polarization upregulating cell surface receptor expression and thereby enhancing virus replication. Our findings provide an increased understanding of the host factors in macrophages governing susceptibility to filoviruses and identify novel murine receptors mediating EBOV entry.
Cognitive function prior to systemic therapy and subsequent well-being in older breast cancer survivors: Longitudinal findings from the Thinking and Living with Cancer Study.

Objective To investigate the relationships between self-reported and objectively measured cognitive function prior to systemic therapy and subsequent well-being outcomes over 24 months in older breast cancer survivors. Methods Data were from 397 women aged 60 to 98 diagnosed with non-metastatic breast cancer in the Thinking and Living with Cancer Study recruited from 2010-2016. Cognitive function was measured at baseline (following surgery, prior to systemic therapy) using neuropsychological assessments of attention, processing speed, and executive function (APE), learning and memory (LM), and the self-reported FACT-Cog scale. Well-being was measured using the FACT-G functional, physical, social, and emotional well-being domain scales at baseline and 12 and 24 months later, scaled from 0 (low) to 100 (high). Linear mixed-effects models assessed the relationships between each of baseline APE, LM, and FACT-Cog quartiles with well-being scores over 24 months, adjusted for confounding variables. Results At baseline, older survivors in the lowest APE, LM, and FACT-Cog score quartiles experienced poorer global well-being than those in the highest quartiles. At 24 months, older survivors tended to improve in well-being, and there were no differences according to baseline APE or LM scores. At 24 months, mean global well-being was 80.3 (95% CI: 76.2-84.3) among those in the lowest vs 86.6 (95% CI: 83.1-90.1) in the highest FACT-cog quartile, a clinically meaningful difference of 6.3 points (95% CI: 1.5-11.1). Conclusions Among older breast cancer survivors, self-reported, but not objective cognitive impairments, were associated with lower global well-being over the first 2 years of survivorship.
Intraoperative margin assessment in head and neck cancer using label-free fluorescence lifetime imaging, machine learning and visualization

Accurate cancer margin assessment prior to surgical resection is a key factor influencing the long-term survival of oral and oropharyngeal cancer patients. This leads to the need for additional guidance tools for real-time delineation of cancer margins. In this work, fiber-based fluorescence lifetime Imaging (FLIm) was combined with machine learning to perform intraoperative tumor identification. The developed classifier achieved a measurement-level ROC-AUC of 0.89±0.03 on an N=62 patient dataset. A transparent overlay of classifier output was augmented onto the surgical field and updated through tissue motion correction, ensuring co-registration between tissue and spectroscopic data/classifier output was maintained during imaging..
Atypical Presentation of Fatal Disease: Painless Aortic Dissection.

Aortic dissections (ADs) are uncommon but they are highly lethal. Due to atypical signs and symptoms, diagnosis of type B AD can be easily missed or delayed. Our patient presented to the emergency center with dizziness and fall for which he was evaluated and treated for hypertension. Two weeks later, he again presented to the hospital with painless right groin swelling: computed tomography (CT) of the abdomen incidentally showed type B AD. The patient might have an AD presenting with dizziness and hypertension during previous presentation. From this case, we learn how it is challenging to diagnose painless AD especially when patient comes with atypical symptoms. In high-risk patients with unexplained dizziness and fall, a high degree of suspicion may help for early diagnosis and management.
Everything I Needed to Know: Empirical Investigations of Copyright Norms in Fandom

In 2008 I published a Note in the Vanderbilt Journal of Technology & Entertainment Law titled "Everything I Need to Know I Learned from Fandom: How Existing Social Norms Can Help Shape the Next Generation of User-Generated Content." My question of "what can we learn from fandom?" turned into a theory—that the strong social norms surrounding copyright in fandom policed behavior and therefore kept it "safe" from copyright holders. I then spent about five years conducting a series of research studies about how fan creators make decisions about what they can and cannot do in a legally gray area, how it impacts the ways they use technology and how they interact with each other, and what these things suggest for how we might design technologies and policies. Over the course of this research, I found that many of the ideas of the original law review note were completely validated, and that one was completely wrong.
Thrombotic thrombocytopenic purpura (TTP) presenting with severe neurological manifestations in a patient with well-controlled HIV-1 (P4.9-010)

Objective: N/A Background: INTRODUCTION: Here we describe a patient with well-controlled HIV presenting with the classic pentad of TTP (fever, neurological manifestations, thrombocytopenia, renal dysfunction, microangiopathic hemolytic anemia) with undetectable ADAMS13 activity and elevated levels of inhibitor autoantibodies, in the absence of other risk factors for TTP. This case highlights the challenges of diagnosing idiopathic vs secondary TTP in the setting of HIV infection. Design/Methods: N/A Results: CASE DESCRIPTION: 43 y/o woman with PMHx HIV on raltegravir and truvada (last CD4 count 647 cells/μL, viral load undetectable 5 months prior), CAD who presented with transient left sided numbness x20 minutes, followed by headache and aphasia. MRI with multiple embolic appearing strokes in the bilateral cerebral hemispheres and cerebellar vermis. Patient thrombocytopenic to 15k/μL, Hb/Hct 8.4/24.0, creatinine elevated to 1.37 mg/dL. LDH elevated at 721 U/L, with rare schistocytes noted on peripheral blood smear. Fibrinogen was normal, with undetectable haptoglobin and negative DAT. Hematology felt these laboratory values were consistent with a microangiopathic hemolytic anemia (MAHA). Overnight patient noted to have progressive aphasia, hyperreflexia and agitation, with low grade fevers to 100.9° F. ADAMS13 activity Conclusions: DISCUSSION: Thrombotic microangiopathies (TMAs) are well-recognized and documented complications of advanced HIV infection. HIV-associated secondary TTP is most commonly associated with CD4 counts Disclosure: Dr. Kimbrough has nothing to disclose. Dr. Sanmartin has nothing to disclose. Dr. Patedakis Litvinov has nothing to disclose. Dr. Navaratnam has nothing to disclose.
A Bipolar Hybrid Circuit Breaker for Low-Voltage DC Circuits

Presently available dc breakers fall into three categories, mechanical, static, and hybrid dc breakers. With the advent of dc circuits, generation, and loads, dc breakers are required for system protection. This paper proposes a new alternate method to break dc currents for low-voltage applications. The proposed mechanism utilizes two switches along with two diodes, to reverse the direction of the current flow and clear the fault. This is different than the conventional single-switch commute-and-absorb method used in mechanical or static breakers in the sense that it reverses the current direction and delivers part of the fault energy back to the source. It is shown that the proposed method can break the fault current effectively with minimal arc and significantly reduces the voltage stress across the mechanical switches.
Observations of severe in-flight environments on airplane composite structural components

The development of relatively inexpensive, highly sophisticated avionics systems makes it now possible for general aviation aircraft to fly under more severe weather conditions than formerly. Increased instrument flying increases exposure of aircraft to potentially severe thunderstorm activity such as high rain rates, hail stones, and lightning strikes. In particular, the effects of lightning on aircraft can be catastrophic. Interest in aircraft lightning protection has been stimulated by the introduction of advanced composites as an aircraft structural material. The present investigation has the objective to report experiences with three composite components which have flown in thunderstorms, taking into account three F-106B composite fin caps. The only visible lightning strike damage to a flame sprayed aluminum coated glass/epoxy fin cap was a small area of the aluminum which was burned. Visible lightning strike damage to a Kevlar/epoxy fin cap was limited to the exterior ply of aluminum coated glass fabric. In the case of a graphite/epoxy fin cap, lightning currents could be conducted.
A Variable Fidelity Model Management Framework for Multiscale Computational Design of Continuous Fiber SiC-Si3N4 Ceramic Composites

Research applications involving design tool development for multiple phase material design are at an early stage of development. The computational requirements of advanced numerical tools for simulating material behavior such as the finite element method (FEM) and the molecular dynamics method (MD) can prohibit direct integration of these tools in a design optimization procedure where multiple iterations are required. The complexity of multiphase material behavior at multiple scales restricts the development of a comprehensive meta-model that can be used to replace the multiscale analysis. One, therefore, requires a design approach that can incorporate multiple simulations (multi-physics) of varying fidelity such as FEM and MD in an iterative model management framework that can significantly reduce design cycle times. In this research a material design tool based on a variable fidelity model management framework is presented. In the variable fidelity material design tool, complex “high fidelity” FEM analyses are performed only to guide the analytic “low-fidelity” model toward the optimal material design. The tool is applied to obtain the optimal distribution of a second phase, consisting of silicon carbide (SiC) fibers, in a silicon-nitride (Si3 N4 ) matrix to obtain continuous fiber SiC-Si3 N4 ceramic composites (CFCCs) with optimal fracture toughness. Using the variable fidelity material design tool in application to one test problem, a reduction in design cycle time around 80 percent is achieved as compared to using a conventional design optimization approach that exclusively calls the high fidelity FEM.Copyright © 2007 by ASME
Evaluation of 1.2 kV, 100A SiC modules for high-frequency, high-temperature applications

Cumulative advances in substrate quality and device manufacturing yields over the past few years have paved the way for the commercial introduction of Silicon Carbide (SiC) power modules capable of supporting applications in the 10-20 kW load class and beyond. This paper investigates the suitability of one such module for high-frequency operation at elevated temperatures by leveraging a high-peak-current gate-drive circuit and careful management of parasitic-induced oscillations. Clamped-inductive load experiments have been carried out at elevated temperatures, and the results compared to published results for similar-scale prototype modules. This work demonstrates achievement of very fast slew rates and switching times; the resulting switching losses are 50-70% lower than figures reported in the literature for modules of this scale.
Household equivalence scales and the measurement of inequality: Transfers from the poor to the rich could decrease inequality

Abstract The use of equivalence scales when measuring income inequality can lead to the paradoxical result that transferring money from poor to wealthy households may reduce measured inequality. This paper explains this result and restates the Pigou–Dalton transfer axiom in a way that gets around this counterintuitive outcome.
A mass conserving modal analysis for elastohydrodynamic lubrication

A computational model which reflects both bearing elasticity and mass conservation is presented for transient elastohydrodynamic analysis. Bearing deformation is represented by a combination of elastic mode shapes coupled with a finite element film model which conserves lubricant mass everywhere. The formulation is applied to a big-end connecting-rod bearing which is lubricated through a crankpin feed-hole.
Universal Health Insurance Coverage: Progress and Issues.

Jonathan Gruber was a key architect of Massachusetts’ ambitious health reform effort, and in 2006 became an inaugural member of the Health Connector Board, the main implementing body for that effort. He delivered this lecture on October 2, 2009, and his references are to Congressional bills that were under consideration on that date. He laid out the universal coverage debate that’s gone on for a long time in the United States; described a new solution that he think they found for Massachusetts; described how the Massachusetts reform works; and how it can be extended nationally. Finally he spent time on the key issues that Congress is facing in fall 2009 trying to take this model to the national level.
Detection of Escherichia coli Antigens by a Latex Agglutination Test

A latex particle agglutination technique to detect ethylenediaminetetraacetate-solubilized extracts from Escherichia coli and whole E. coli cells is described. The sensitivity of the serological test was found to be 0.5 to 2.5 ng for the solubilized antigens and 1.5 x 10(6) to 5.7 x 10(6) cells per ml for the particulate antigens. The test was 100 to 1,000 times more sensitive than the standard bacterial agglutination test. Furthermore, it detected E. coli antigens during all phases of bacterial growth, whereas the bacterial test detected the antigens only after the mid-log phase. No significant cross-reactivity was observed between latex-anti-E. coli preparations and heterologous bacterial strains used in the experimental procedure. A buffer formula containing fatty acid-free bovine albumin prevented nonspecific aggregation of the latex particles.
Effect of temperature on rectifying Schottky barriers formed from fingerprint sweat corrosion of brass.

: Corrosive electrochemical processes of brass, including those resulting from fingerprint sweat, continue to be studied because of the widespread industrial use of brass. Here, we examine how increased temperature affects the relative abundance of fingerprint sweat corrosion products and the rectifying Schottky barrier formed between p-type copper (I) oxide corrosion and brass. X-ray photoelectron spectroscopy confirms increasing dezincification with increasing temperature. This leads to n-type zinc oxide replacing copper (I) oxide as the dominant corrosion product, which then forms a rectifying Schottky barrier with the brass, instead of copper oxide, when the temperature reaches c. 600°C. Using X-ray diffraction, resulting diodes show polycrystalline oxides embedded in amorphous oxidation products that have a lower relative abundance than the diode forming oxide. Conventional current/voltage (I/V) characteristics of these diodes show good rectifying qualities. At temperatures between c. 100 and c. 600°C, when neither oxide dominates, the semiconductor/brass contact displays an absence of rectification.
Previously Uncultured Marine Bacteria Linked to Novel Alkaloid Production

Low-nutrient media and long incubation times facilitated the cultivation of 20 taxonomically diverse Gram-negative marine bacteria within the phyla Bacteroidetes and Proteobacteria. These strains comprise as many as three new families and include members of clades that had only been observed using culture-independent techniques. Chemical studies of the type strains representing two new families within the order Cytophagales led to the isolation of nine new alkaloid secondary metabolites that can be grouped into four distinct structure classes, including azepinones, aziridines, quinolones, and pyrazinones. Several of these compounds possess antibacterial properties and appear, on structural grounds, to be produced by amino acid-based biosynthetic pathways. Our results demonstrate that relatively simple cultivation techniques can lead to the isolation of new bacterial taxa that are capable of the production of alkaloid secondary metabolites with antibacterial activities. These findings support continued investment in cultivation techniques as a method for natural product discovery.
Lower subcortical gray matter volume in both younger smokers and established smokers relative to non‐smokers

Although established adult smokers with long histories of nicotine dependence have lower neural tissue volume than non-smokers, it is not clear if lower regional brain volume is also observed in younger, less established smokers. The primary goal of this study was to investigate neural tissue volume in a large group of smokers and non-smokers, with a secondary goal of measuring the impact of age on these effects. We used voxel-based morphometry to compare regional gray matter volume in 118 individuals (59 smokers, 59 age- and gender-matched non-smokers). Younger smokers had significantly lower gray matter volume in the left thalamus and the left amygdala than their non-smoking peers (family-wise error-corrected clusters, P < 0.05). There was no correlation between smoking use variables and tissue volume among younger smokers. Established smokers had significantly lower gray matter volume than age-matched non-smokers in the insula, parahippocampal gyrus and pallidum. Medial prefrontal cortex gray matter volume was negatively correlated with pack-years of smoking among the established smokers, but not the younger smokers. These data reveal that regional tissue volume differences are not limited exclusively to established smokers. Deficits in young adults indicate that cigarette smoking may either be deleterious to the thalamus and amygdala at an earlier age than previously reported, or that pre-existing differences in these areas may predispose individuals to the development of nicotine dependence.
Mechanism of α-Glycerophosphate Regulation of Acetyl-Coenzyme A Carboxylase of Saccharomyces cerevisiae

The mechanism proposed for the activation of animal acetyl-coenzyme A (CoA) carboxylase by α-glycerophosphate, namely, the removal of inhibitory palmityl-CoA via glyceride synthesis, is not the only possible one in the yeast system because extracts exhibiting marked stimulation of acetyl-CoA carboxylase activity by α-glyerophosphate show a lack of acyl-CoA compounds.
Cognitive Bridges: The Case of High School Undercover Officers

This article explores the problem of social integration from a position of isolation. It uses the experiences of high school undercover officers to consider the problem conceptually. Officers must move from new student to peer to drug purchaser without any informant assistance and with severe time constraints. Three specific techniques are used to trigger this process: class clowning, retreatism, and troublemaking. Each is a variation on the single theme of rebellion. I argue that these techniques generate interpersonal familiarity from a distance by creating reputations that drug dealers identify with and vest legitimacy in. Reputation substitutes for introductions informants could otherwise give, establishes a pretransaction comfort zone, and lays the interpersonal groundwork officers need before they can solicit drugs. Officers' behavior is conceptualized through the notion of a cognitive bridge, a hybrid of interactionist and microstructural principles. Data are drawn from interviews with thirty undercover officers who operate from a large western U.S. municipality. Effective undercover officers must be good thespians. Through dramaturgical methods, they induce targeted offenders into believing dissembled identities are real ones. Doing this without the help of an informant can be a daunting task. Familiar to the subculture, informants vouch for officers' legitimacy and ease their way into association with offenders (Brown 1985; Williams and Guess 1981). Without informants, officers must use their own interpersonal skills to move from subcultural outcast to peer. High school undercover narcs, police officers who pose as new students seeking to buy drugs from dealers, face this microstructural dilemma.
An analysis of a method for solving singular integral equations

We establish convergence rates for a method of approximate solution of certain singular integral equations. The method considered involves an expansion of the kernel of the equation in terms of Chebyshev polynomials.
Privatizing water: governance failure and the world's urban water crisis

Privatizing water: governance failure and the world's urban water crisis, by Karen Bakker, New York, Cornell University Press, 2010, xvi + 303 pp., index, £42.95 (hardback), ISBN 9780801447235, £16...
Physiological amino acids in the brain of Schistocerca americana (Insecta), Lycosa avida (Arachnida) and Eurypanopeus depressus (Decapoda)

Abstract 1. An analysis of the physiological amino acids in the brains of Schistocerca americana (Orthoptera). Lycosa avida (Arachnida) and Eurypanopeus depressus (Decapoda) was conducted. 2. Nitrogenous waste products (ammonia and urea) together constituted 53% of the total ninhydrin-positive compounds in L. avida. 32% in S. americana and 20% in E. depressus. 3. GABA accounted for 9% of the total ninhydrin-positive compounds in the brain of L. avida, 7% in E. depressus and 3% in S. americana. 4. The most abundant amino acids were alanine and taurine in L. avida, alanine, proline and glutamic acid in S. americana, and taurine, proline, alanine and aspartic acid in E. depressus. Asparagine and glutamine appear to be present in higher concentrations in the brain of insects as compared to concentrations found in arachnids and decapods. Ornithine was not detected in the brains of any of the species studied.
Perturbation analysis of nonuniform almost-periodic Bragg reflectors

Periodic structures that vary spatially in coupling strength, period, and gain/loss are analyzed using a perturbation technique to determine their response as Bragg reflectors or filters. A formula for the response, accurate to first order in the perturbation, is given. Results obtained by evaluating the formula are presented graphically. It is also shown analytically that antisymmetric variations in coupling and/or periodicity have a negligible effect on response (to first order) when neither gain nor loss is present.
Determination of the stenotic aortic valve area in adults using Doppler echocardiography

The severity of aortic stenosis was evaluated by Doppler echocardiography in 48 adults (mean age 67 years) undergoing cardiac catheterization. Maximal Doppler systolic gradient correlated with peak to peak pressure gradient (r = 0.79, y = 0.63x + 25.2 mm Hg) and mean Doppler gradient correlated with mean pressure gradient (r = 0.77, y = 0.51x + 10.0 mm Hg) by manometry. The transvalvular pressure gradient is flow dependent, however, and associated left ventricular dysfunction was common in our patients (33%). Thus, of the 32 patients with an aortic valve area less than or equal to 1.0 cm2at catheterization, 6 (19 %) had. a peak Doppler gradient less than 50 mm Hg. To take into account the influence of volume flow, aortic valve area was calculated as stroke volume, measured simultaneously by thermodilution, divided by the Doppler systolic velocity integral in the aortic jet. Aortic valve areas calculated by this method were compared with results at catheterization in the total group (r = 0.71). Significant aortic insufficiency was present in 71 % of the population. In the subgroup without significant coexisting aortic insufficiency, closer agreement of valve area with catheterization was noted (n = 14, r = 0.91, y = 0.83x + 0.24 cm2). Transaortic stroke volume can be determined noninvasively by Doppler echocardiographic measures in the left ventricular outflow tract, just proximal to the stenotic valve. Aortic valve area can then be calculated as left ventricular outflow tract cross-sectional area times the systolic velocity integral of outflow tract flow, divided by the systolic velocity integral in the aortic jet. Using this approach, noninvasive aortic valve areas compared well with valve areas calculated at catheterization (r = 0.86, y = 0.96x + 0.19 cm2). A simple index, derived as the ratio of the systolic velocity integral in the left ventricular outflow tract to that in the aortic jet, provided better identification of patients with severe stenosis (sensitivity = 97%) than did the Doppler pressure gradient alone (sensitivity = 81%). These results show that noninvasive calculation of aortic valve area using Doppler echocardiography is feasible. The simple Doppler ratio may be useful clinically for identifying patients with severe stenosis, especially when low transaortic flow is suspected.
Multiplex PCR/LDR for detection of K- ras mutations in primary colon tumors

Point mutations in codons 12, 13, and 61 of the K-ras gene occur early in the development of colorectal cancer and are preserved throughout the course of tumor progression. These mutations can serve as biomarkers for shed or circulating tumor cells and may be useful for diagnosis of early, curable tumors and for staging of advanced cancers. We have developed a multiplex polymerase chain reaction/ligase detection reaction (PCR/LDR) method which identifies all 19 possible single-base mutations in K-ras codons 12, 13, and 61, with a sensitivity of 1 in 500 wild-type sequences. In a blinded study, 144 paraffin-embedded archival colon carcinomas were microdissected and K-ras mutations determined by both dideoxy-sequencing and multiplex PCR/LDR. Results were concordant for 134 samples. The ten discordant samples were re-evaluated using higher sensitivity uniplex PCR/LDR, and the original multiplex PCR/LDR result was confirmed in nine of these ten cases. Multiplex PCR/LDR was able to identify mutations in solid tumors or paraffin-embedded tissues containing a majority of wild-type stromal cells, with or without microdissection. The technique is well suited for large scale studies and for analysis of clinical samples containing a minority population of mutated cells.