cssi/SciSciGPT-SciSciNet huggingface dataset:
Microwave Sensing of the Ocean Surface

A review of electromagnetic (e.m.) and hydrodynamic processes pertinent to the backscatter of microwaves from water/ocean waves is presented. The understanding of e.m. scattering from the ocean has increased rapidly in the past two decades. The enhanced knowledge has allowed the probing of ocean waves with radio/microwaves, paving the way for the success of the first oceanographic satellite in 1978, SEASAT. In the future, as the calibration of microwave sensors improve, satellite measurements of the world oceans should become routine. In particular, the forthcoming 1989–1994 World Ocean Circulation Experiment (WOCE) will rely on microwave measurements from space for wind stress and geostrophic currents information.
Special Disease Management Considerations

In this chapter, we present clinical scenarios of patients with spontaneous intracerebral hemorrhage, intraventricular hemorrhage, and hemorrhages secondary to underlying brain arteriovenous malformation and dural arteriovenous fistulas. Based on current available evidence, we also discuss management for each of the above conditions.
Beyond the lateral flow assay: A review of paper-based microfluidics

Abstract The interest in and use of microfluidic paper-based analytical devices (μPADs) has grown exponentially over the last decade. Cellulose, and modified cellulose, has been used for centuries for making chemical measurements but devices made with this material traditionally suffered from either poor detection limits and/or limited ability to provide quantitative measurements. μPADs address these problems by patterning paper to create microfluidic channel networks that can direct flow to different regions of the device without the need for external pumps used in most traditional microfluidic devices. Furthermore, because the devices are made from cellulose or modified cellulose using inexpensive manufacturing methods, the devices can be inexpensive and disposable. The ability to carry out multiplexed analysis without external pumps using inexpensive, disposable devices makes μPADs ideal for point-of-care (POC) analysis. The interest in μPADs has led to a number of excellent comprehensive reviews in the field; in this review, we do not attempt to reference the entire field but instead seek to highlight major developments as well as areas that will be important for future development of this field.
Strategic Borrowing from Passive Investors: Implications for Security Lending and Price Efficiency

We examine the effects of passive investing on security lending outcomes and price efficiency for the 2007-2017 period. These findings cannot be fully explained by the standard lending supply channel. While all institutional investors contribute to lending supply, only passive ownership improves price efficiency. Additionally, increased passive ownership correlates with higher lending fees and higher short interest. We propose a complementary, demand-based strategic borrowing channel wherein short-sellers prefer to borrow from passive investors to reduce dynamic short-selling risks. Consistent with our hypotheses, increased passive ownership is associated with lower fee, recall, and information leakage risks, and longer loan duration.
Plenary: Twenty Year Retrospective on 1969 Science Paper of C. Starr, “Social Benefit vs. Technological Risk”

Those of us who believe that human welfare is significantly aided by technological progress have a clear motivation to accentuate the positive and to mitigate the negative consequences of technology. We thus share a common objective to allocate our limited societal resources effectively so as to improve public health and safety by minimizing real risks, both present and future.
Using Predictive Models to Estimate the Properties of Binders in Reclaimed Asphalt Pavement Mixes using Fine Aggregate Matrix Mix Testing

A number of predictive models, such as the Hirsch and Al-Khateeb models, have been proposed to determine the properties of asphalt binders from asphalt concrete mix testing results. Fine aggregate ...
Metabolism of benzo[a]pyrene in human bronchoalveolar H358 cells by LC-MS

1396 Benzo[a]pyrene (BP), is a representative polycyclic aromatic hydrocarbon (PAH), which can be metabolically activated by three enzyme pathways, P450-peroxidase, P4501A1/1B1, and aldo-keto reductases (AKRs). The profile of BP metabolites in human lung epithelial cells using modern methods is not well studied even though lung is a major PAH exposure site due to the inhalation of first and second hand tobacco smoke. In this study, BP-metabolites generated by P450 peroxidase (BP-1,6- and 3,6-dione), by P4501A1/1B1 (3-hydroxyl-BP, BP-7,8- and 9,10-dihydrodiols, and BP-r-7,t-8,t-9,c-10-tetrahydrotetrol), and by AKRs (BP-7,8-dione) in human bronchoalveolar H358 cells were quantified by RP-HPLC with radiometric detection and identified by LC-MS. LC/MS data were acquired using a Thermo Finnigan TSQ Quantum Ultra spectrometer with an atmospheric pressure chemical ionization source operated in the positive-ion mode and on-line chromatography was performed with a Waters Alliance 2690 HPLC system. The eluent on-line was monitored in the selected reaction monitoring mode and full-scan modes and ion-transitions compared to those obtained with authentic synthetic standards. Progress curves showed a lag-phase in the formation of 3-hydroxy-BP > BP-9,10-dihydrodiol > BP-7,8-dihydrodiol > BP-tetrol > BP-1,6-dione and BP-7,8-dione over 24 h. Northern blot analysis showed induction of P4501B1 and AKR1C1 by BP in a time-dependent manner, suggesting that BP stimulates its own metabolism by induction of these key enzymes. By contrast BP-3,6-dione was formed without a lag-phase. Pretreatment with 10 nM TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) eliminated the lag-phase but the levels of the individual metabolites were unaltered suggesting that TCDD induction alters the kinetics of metabolite formation but not metabolite levels. This study provides evidence for the formation of reactive BP metabolites from each of the pathways of PAH-activation in human lung bronchoalveolar cells (Supported by P01-CA092537 and R01-CA39505).
The Brain on Beauty: Neuroaesthetics

Semir Zeki coined the word “neuro-esthetics” (neuroaesthetics) in 1999. The first neuroaesthetic study was published in 2000 (Hansen, Brammer, & Calvert), followed by three seminal papers in 2004 (Vartanian & Goel; Kawabati & Zeki; Cela-Conde et al.). Why do we find something beautiful? Evo Psyc might be able to tell us. How do we find things beautiful? Neuroaesthetics sheds light on that. “The aesthetic triad” comprises the interaction of three neural systems to create our aesthetic experiences: the sensory-motor system, the emotion-valuation system, and the knowledge-meaning system (Chatterjee & Vartanian, Trends in Cognitive Sciences 370–375, 2014, Annals of the New York Academy of Sciences 172–194, 2016). Experiences of beauty involve the pleasure centers and reward circuits of the brain; pleasure may be a necessary, but not sufficient, condition for experiences of beauty. The medial orbitofrontal cortex (mOFC) may be involved in all or most experiences of beauty (Ishizu & Zeki, PLoS One e21852, 2011). However, caution is warranted in making such a claim. The meta-analytic review by Brown et al. (NeuroImage 250–258, 2011) indicated that the right anterior insula was the main nexus of all beauty experiences but that different kinds of beauty (taste, scent, visual, auditory) were processed in different parts of the orbitofrontal cortex (OFC). Observing moral beauty may be simultaneously arousing and calming (activating both the sympathetic and parasympathetic nervous systems).
Abstract TP143: Credibility, Expectancy and Satisfaction With Community-Based Telepractice Treatment for Aphasia

Introduction: Telepractice has been used successfully to treat acute stroke in individuals in rural communities. Less progress has been made in using this approach for the treatment of post-stroke ...
Temperature check: theory and practice for training models with softmax-cross-entropy losses

The softmax function combined with a cross-entropy loss is a principled approach to modeling probability distributions that has become ubiquitous in deep learning. The softmax function is defined by a lone hyperparameter, the temperature, that is commonly set to one or regarded as a way to tune model confidence after training; however, less is known about how the temperature impacts training dynamics or generalization performance. In this work we develop a theory of early learning for models trained with softmax-cross-entropy loss and show that the learning dynamics depend crucially on the inverse-temperature β as well as the magnitude of the logits at initialization, ||βz||2. We follow up these analytic results with a large-scale empirical study of a variety of model architectures trained on CIFAR10, ImageNet, and IMDB sentiment analysis. We find that generalization performance depends strongly on the temperature, but only weakly on the initial logit magnitude. We provide evidence that the dependence of generalization on β is not due to changes in model confidence, but is a dynamical phenomenon. It follows that the addition of β as a tunable hyperparameter is key to maximizing model performance. Although we find the optimal β to be sensitive to the architecture, our results suggest that tuning β over the range 10−2 to 101 improves performance over all architectures studied. We find that smaller β may lead to better peak performance at the cost of learning stability.
Contract Law and Social Morality

When people in a relationship disagree about their obligations to each other, they need to rely on a method of reasoning that allows the relationship to flourish while advancing each person's private projects. This book presents a method of reasoning that reflects how people reason through disagreements and how courts create doctrine by reasoning about the obligations arising from the relationship. Built on the ideal of the other-regarding person, Contract Law and Social Morality displays a method of reasoning that allows one person to integrate their personal interests with the interests of another, determining how divergent interests can be balanced against each other. Called values-balancing reasoning, this methodology makes transparent the values at stake in a disagreement, and provides a neutral and objective way to identify and evaluate the trade-offs that are required if the relationship is to be sustained or terminated justly.
Trends in the Incidence of Hepatocellular Carcinoma in Washington DC: A Single Institutional Cohort Study (1959-2013).

Abstract The African American (AA) community in Washington DC is at an elevated risk for hepatocellular carcinoma (HCC) that has a dismal prognosis. The recent rapid increase in the incidence and diagnosis of HCC and liver metastases (LM) in DC prompted us to evaluate the past six decades of this incidence and some of its underlying causes using a single institutional cohort in a hospital located in the center of the city. Electronic medical and pathology records of 454 liver cancer patients from 1959 to 2013 at Howard University Hospital (HUH) were reviewed. Demographic, clinical and pathology characteristics were examined, and statistical analysis was performed using Wilcoxon rank-sum test. Incidence of HCC rose substantially between 1959 and 2013, increasing eight-fold from 1.05 to 8.0 per 100,000 AAs. The rate of increase in the last decade was highest at 550%. Cases were disproportionately male (67.2%), and median age at diagnosis was 57 years. Towards the last decade, the most common etiology for HCC was nonalcoholic fatty liver disease (NAFLD) followed by NAFLD/HCV combination. Liver cancer was clustered in the eastern region of DC in wards 4, 5, 7, and 8. Cases of liver metastases clinically diagnosed and confirmed by biopsies increased 96.4% from 1959 to 1968 to 2009-2013. This study confirms that HCC incidence has been increasing (initially driven by HCV, and NAFLD in the latter decades) more rapidly in DC than previously believed, highlighting the impact of case definitions especially regarding NAFLD in the context of changing diagnostic approaches including the revised ICD10. The rising burden, disproportionate population distribution, and low survival rate among AAs emphasize the importance of prevention and early detection as a public health imperative.
Silver (I)-dimercaptotriazine functionalized silica: A highly selective liquid chromatography stationary phase targeting unsaturated molecules

Abstract Silver(I)-mercaptopropyl (Ag-MP) functionalized silica gel has demonstrated its effectiveness in separating various unsaturated organic compounds including unsaturated fatty acid ethyl esters (FAEEs), triglycerols (TAGs) and long-chain alkyl ketones (alkenones). While Ag-MP stationary phase displays many advantages over the conventional silver ion-impregnated silica gel (e.g., stability, high recovery, etc.), potential drawbacks of Ag-MP include relatively low retentions for unsaturated molecules, which could limit chromatographic resolutions under certain circumstances. In this study, we evaluate a new silver-thiolate stationary phase: silver(I)-dimercaptotriazine (Ag-DMT) functionalized silica gel targeting the separation of unsaturated compounds. We show Ag-DMT affords substantially higher retention factors, peak resolutions and capacities for TAGs and FAEEs than Ag-MP does. Ag-DMT also yields higher purity eicosapentaenoic acid (EPA) from fish oil FAEE mixtures than Ag-MP. In addition, Ag-DMT resolves double bond positional and cis/trans-isomers of C18:1 fatty acid methyl esters (FAMEs) as well as unsaturated methyl/ethyl alkenones with different number of double bonds. Based on van't Hoff plots, enthalpy changes during the adsorption of unsaturated FAEEs onto Ag-DMT are ~2 times higher than those on Ag-MP. Such difference may be attributed to the stronger electron-withdrawing effect of the thiol group on DMT, which results in more positively charged silver ions hence greater interactions with unsaturated molecules. The stronger interaction between double bonds and Ag-DMT is further corroborated by density-functional theory (DFT) calculations. Ag-DMT shows its high stability for repeated uses in the separation of TAGs over 319 runs, with peak resolutions decreasing by
Framing clinical and translational science: Examining the strategic social media communications of NCATS-funded CTSAs.

Introduction Many Clinical and Translational Science Awards (CTSAs) focus their energy on operational aspects of running their hub, but may not devote enough energy and resources toward branding and effective communication. However, CTSAs have an important mission when it comes to communicating effectively with their stakeholders through social media. Using framing theory as the underpinning, the purpose of this content analysis is to investigate the ways in which CTSAs use Twitter to communicate with their various stakeholders, the type of content they post, and the type of engagement their tweets garner. Methods We examined 349 tweets posted from January 2019 to January 2020 from 19 CTSA Twitter accounts (sampled from a total of 35 CTSA accounts). A thematic codebook was generated using tweets randomly chosen from the sample. Content analysis was performed on the entire tweet sample by four coders using the codebook (alpha = 0.89). Results CTSAs tweeted the most about events (29.8%), and the least about study recruitment (2.01%). Most tweets included images (59.31%) and hashtags (51.29%), but received little user engagement on the average post (average: 4.38 likes and 1.94 retweets). CTSAs tweeted most from 10 a.m. to 12 p.m. PST and received the most engagement. Most CTSAs had a dedicated person (e.g., manager, coordinator) handling their communications. Discussion Our analysis shows multiple opportunities for CTSAs to engage with stakeholders and the public, as well as standardize and improve their Twitter communications to effectively reach a broader audience.
Examining the Effects of the Nitrogen Environment on Growth and N2-Fixation of Endophytic Herbaspirillum seropedicae in Maize Seedlings by Applying 11C Radiotracing

Herbaspirillum seropedicae, as an endophyte and prolific root colonizer of numerous cereal crops, occupies an important ecological niche in agriculture because of its ability to promote plant growth and potentially improve crop yield. More importantly, there exists the untapped potential to harness its ability, as a diazotroph, to fix atmospheric N2 as an alternative nitrogen resource to synthetic fertilizers. While mechanisms for plant growth promotion remain controversial, especially in cereal crops, one irrefutable fact is these microorganisms rely heavily on plant-borne carbon as their main energy source in support of their own growth and biological functions. Biological nitrogen fixation (BNF), a microbial function that is reliant on nitrogenase enzyme activity, is extremely sensitive to the localized nitrogen environment of the microorganism. However, whether internal root colonization can serve to shield the microorganisms and de-sensitize nitrogenase activity to changes in the soil nitrogen status remains unanswered. We used RAM10, a GFP-reporting strain of H. seropedicae, and administered radioactive 11CO2 tracer to intact 3-week-old maize leaves and followed 11C-photosynthates to sites within intact roots where actively fluorescing microbial colonies assimilated the tracer. We examined the influence of administering either 1 mM or 10 mM nitrate during plant growth on microbial demands for plant-borne 11C. Nitrogenase activity was also examined under the same growth conditions using the acetylene reduction assay. We found that plant growth under low nitrate resulted in higher nitrogenase activity as well as higher microbial demands for plant-borne carbon than plant growth under high nitrate. However, carbon availability was significantly diminished under low nitrate growth due to reduced host CO2 fixation and reduced allocation of carbon resources to the roots. This response of the host caused significant inhibition of microbial growth. In summary, internal root colonization did little to shield these endophytic microorganisms from the nitrogen environment.
Spiking Neuromorphic Networks for Binary Tasks

In this paper, we focus on the hand construction of small-scale, spiking, neuromorphic networks. They are partitioned into two sets. The first set performs the binary operations AND, OR and XOR. For each of these operations, there are eight scenarios that we consider, with four types of encodings of binary values to spikes, and neurons that feature or prohibit leak. The second set of networks perform conversions of binary values from one type of encoding to another, again considering both leak or no leak. These networks are presented graphically and with spike-raster plots that illustrate their activity. We tabulate metrics of interest concerning the size, activity and speed of these networks. Our goal with this work is to enable the composition of multiple spiking neural networks, perhaps trained with other methodologies, without requiring information to leave a neuroprocessor for processing by conventional hardware.
Hearts and Hahas of the Public: Exploring How Protest Frames and Sentiment Influence Emotional Emoji Engagement with Facebook News Posts

The protest paradigm, which describes the unequitable reciprocity of the media-social movement relationship, creates a double-bind for social movements. Mainstream news media in the United States e...
Quantitative Methods in Thin-Layer Chromatography

Physical, chemical and instrumental sources of error in quantitative thin-layer chromatography using slit-scanning densitometry are identified, and where possible, practical solutions for their control are indicated. Mathematical transformations of non-linear calibration data are identified as an additional source of error that can be avoided by using nonlinear regression models. In addition, some alternative techniques to quantification by slit-scanning densitometry are considered and their future assessed. From among these, image analyzers and hyphenated techniques such as TLC-SIMS and TLC-SERS, which can provide structural information from TLC spots for identification purposes, are highlighted as being likely to become more important in the near future.
Burnout — A Study of a Psychiatric Center

(1989). Burnout — A Study of a Psychiatric Center. Loss, Grief & Care: Vol. 3, No. 1-2, pp. 83-93.
Through the Looking-Glass: Joyce’s ‘Circe’, Flaubert’s Madame Bovary and the Poetics of Vision

In the last decades of the nineteenth century reading fiction to articulate a scientific diagnosis breeds a hybrid genre of scientific diagnosis that is both literary and medical. Just as medicine turns to fiction, thus blurring the boundaries between diagnosis and literary criticism, scientific discourses bring about artistic innovations in the novel which assimilates, mimics, and catalogs the discourses of the emerging sciences. In Madame Bovary, Flaubert’s attempt to move away from the romantic tradition is paralleled with his interest in integrating contemporary medical discourses into the narrative of Emma’s story such as hysteria. Like Flaubert, James Joyce does not remain indifferent to the emerging medical discourses. Indeed, in Joyce’s Ulysses, as one enters ‘Circe’s’ theatre of perversions, one leaves the hostile corps medical of ‘Oxen in the Sun’ only to familiarize oneself with yet another kind of linguistic laboratory that is not immune to the tyranny of the medical gaze. Looking at both Flaubert and Joyce, this article reassesses the possible conversations prompted by the dynamic exchange between the scientific and the literary discourses and explores ways in which the assimilation of the sciences of the Modern novel departs from yet remodels that of the realist narrative. Establishing a conversation between Flaubert, Joyce, and Krafft-Ebing, I look at how the conversations between fiction and the sciences generate the ‘medicalization of fiction in the novel and the fictionalization of medical discourses.’ This cross-fertilization between the two disciplines, I suggest, reshapes the ways in which the novel internalizes the concept of the medical gaze in the sciences.
Volume regulation of the hippocampus.

We conclude that cellular taurine is critical for volume regulation of the hippocampus during swelling caused by oxidative stress. Both pyramidal neurons and astroglial cells accumulate taurine in slices treated to restore normal taurine contents. Since H2O2 exposure alters synaptic function via an oxidative mechanism in slices with normal or diminished slice taurine contents, we conclude the effects of taurine are not mediated by the antioxidant properties of the taurine molecule. We suggest loss of taurine from the slice exposed to oxidative stress facilitates regulation of normal cell volume via osmotic effects.
Mortality Attributable to Low Levels of Education in the United States

Background Educational disparities in U.S. adult mortality are large and have widened across birth cohorts. We consider three policy relevant scenarios and estimate the mortality attributable to: (1) individuals having less than a high school degree rather than a high school degree, (2) individuals having some college rather than a baccalaureate degree, and (3) individuals having anything less than a baccalaureate degree rather than a baccalaureate degree, using educational disparities specific to the 1925, 1935, and 1945 cohorts. Methods We use the National Health Interview Survey data (1986–2004) linked to prospective mortality through 2006 (N=1,008,949), and discrete-time survival models, to estimate education- and cohort-specific mortality rates. We use those mortality rates and data on the 2010 U.S. population from the American Community Survey, to calculate annual attributable mortality estimates. Results If adults aged 25–85 in the 2010 U.S. population experienced the educational disparities in mortality observed in the 1945 cohort, 145,243 deaths could be attributed to individuals having less than a high school degree rather than a high school degree, 110,068 deaths could be attributed to individuals having some college rather than a baccalaureate degree, and 554,525 deaths could be attributed to individuals having anything less than a baccalaureate degree rather than a baccalaureate degree. Widening educational disparities between the 1925 and 1945 cohorts result in a doubling of attributable mortality. Mortality attributable to having less than a high school degree is proportionally similar among women and men and among non-Hispanic blacks and whites, and is greater for cardiovascular disease than for cancer. Conclusions Mortality attributable to low education is comparable in magnitude to mortality attributable to individuals being current rather than former smokers. Existing research suggests that a substantial part of the association between education and mortality is causal. Thus, policies that increase education could significantly reduce adult mortality.
Building a Twig Phylogeny.

In this classroom activity, students build a phylogeny for woody plant species based on the morphology of their twigs. Using any available twigs, students can practice the process of cladistics to test evolutionary hypotheses for real organisms. They identify homologous characters, determine polarity through outgroup comparison, and construct a parsimonious tree based on synapomorphies (shared derived characters). This activity efficiently demonstrates many systematics concepts, including homology, homoplasy (convergence and reversal), polarity, synapomorphy, symplesiomorphy, autapomorphy, polytomy, and parsimony. It also engages students in inquiry, promotes student collaboration, raises awareness of plant structure, and exposes students to the diversity of common local trees.
Bevacizumab‐induced transient sixth nerve palsy in ovarian cancer: A case report

We report a case of transient sixth nerve palsy after systemic administration of bevacizumab. Two days after systemic administration of bevacizumab in conjunction with gemcitabine and carboplatin in a 67-year-old woman with recurrent primary ovarian cancer, the patient developed sixth nerve palsy. After bevacizumab was stopped, the complete left sixth nerve palsy resolved spontaneously over the course of 3 months. This is the first reported case of bevacizumab-induced cranial sixth nerve palsy in the treatment of gynecologic malignancy.
An extensive galactic search for conformer II glycine

We have conducted the most extensive galactic search reported to date for conformer II glycine, a higher energy form of the simplest amino acid. The search utilized four glycine transitions at centimeter wavelengths and 21 at millimeter wavelengths to observe 18 galactic molecular sources and one comet. No conformer II glycine lines were detected and measurements of representative sources were used to compute upper limits on total column densities. Several unidentified lines were detected and are reported here with some suggested possible identifications.
Microwave Conductivity of a Plasma in a Magnetic Field

The Boltzmann equation for electrons in a uniform isothermal plasma is solved by expressing the distribution function as a series of orthogonal polynomials in velocity space with time dependent expansion coefficients. The microwave conductivity is simply related to certain coefficients. Particular attention is devoted to the case in which the plasma is subject to a constant magnetic field and a microwave electric field. By introducing an "effective" electron temperature, convergence is attained for strong as well as weak electric fields. The formulation is particularly suited for Problems involving partially ionized gases which contain several species of ions anti neutrals. The conductivity of a completely ionized gas is calculated with and without consideration of electron-electron collisions, and the ratio ( ) of the two results is graphically illustrated as a function of microwave frequency. (auth)
Aqueous two-phase partition coefficients for Escherichia coli β-galactosidase fusions

The partition of native Escherichia coli β-galactosidase and of two different fusion proteins comprised mainly of β-galactosidase from E. coli was studied in aqueous two-phase systems composed of polyethylene glycol (PEG) and dextran. These fusions contain an amino-terminal segment from the E. coli outer membrane protein F (OmpF) and a linker peptide. Differences in the partition pattern could be observed for the three enzymes despite their similarity. Decreased polymer concentrations in the phase system increased the partition coefficient for all three β-galactosidases.
MA1: Ada for real-time and parallel processing

Level - Intermediate. This tutorial assumes basic knowledge or experience with the Ada programming language.This tutorial covers two of the major problems with parallel and real-time programming - time management and storage management. Parallel processing, whether on single-processor machines or multiple processors, has many pitfalls. We will examine these potential pitfalls, and discuss ways to avoid common problems, such as deadlocks and race conditions. We will also discuss how to write code that efficiently passes data with other parallel processes. The basics of parallel processing are covered, leading to a discussion and examples using Ada tasking. In addition, the Ada Real-Time Systems Annex is also covered.
Effects of Minimum Wages on Youth Employment: the Importance of Accounting for Spatial Correlation

The relationship between minimum wage increases and youth employment is investigated using county-level data and spatial econometric techniques. Results that account for spatial correlation indicate that a 10% increase in the effective minimum wage is associated with a 3.2% decrease in youth employment, a result that is 28% higher than the corresponding estimate that does not control for spatial correlation. Thus, estimates that do not take into account spatial correlation may significantly underestimate the negative effect of the minimum wage on teenage employment. Improperly controlling for factors that vary systematically over space can lead to incorrect inferences and misinform policy.
Single-symbol ML decoding for orthogonal and quasi-orthogonal STBC in clipped MIMO-OFDM systems using a clipping noise model with Gaussian approximation

An efficient way to reduce the peak-to-average power ratio (PAPR) in OFDM systems is clipping. After the clipping in an MIMO-OFDM system, the additive noise may not be white. In this paper, we develop fast (single-symbol) ML decoding algorithms for orthogonal space-time block codes (OSTBC) and (linearly transformed) quasi orthogonal space- time block codes (QOSTBC) in clipped MIMO-OFDM systems by using a clipping noise model with Gaussian approximation. By using the statistics of the clipping distortions, our newly developed fast ML decoding algorithms improve the performance for clipped MIMO-OFDM systems with OSTBC and QOSTBC while the decoding complexities are not increased. Simulation results are presented to illustrate the improvement.
Effect of ionic liquids in unimolecular solvolysis reactions involving carbocationic intermediates

Abstract Solvolysis studies of pivaloyl triflate were performed using ionic liquid/methanol solvent mixtures. The rearranged carbocation intermediate reacts with methanol via nucleophilic attack or elimination of a proton. Relative amounts of products were determined through 1 H NMR analysis. For most ionic liquids, increasing the ionic liquid:methanol ratio leads to increased yields of elimination product. Product ratios vary based on Kamlet–Taft solvatochromic parameters of hydrogen bond donating and accepting ability of the ionic liquid.
Evaluation of Impact Damage Resistance in Laminated Composites Using Resins with Different Crosslink Densities

It is generally recognized that fiber-reinforced laminated composites are susceptible to damage resulting from low-velocity impacts. Over recent years, many strategies have been devised to increase the fracture toughness of resin matrix materials with the aim of improving the composites overall resistance to impact damage. One popular strategy for enhancing the fracture toughness of thermosets involves increasing its molecular weight between crosslinks which, in turn, enhances the resins ductility. In this paper, we investigate the efficiency of this toughening approach with regard to resisting damage in composite laminates subjected to lowvelocity impacts. Generic damage characteristics and mechanisms are reviewed and it is shown that two different events occur during the impact process. First, the laminate experiences a local failure which resembles a Hertzian fracture process followed by subsequent delamination between the plies. Results are presented illustrating the effects that systematically increasing the molecular weight between crosslinks of the resin has on each of these mechanisms. Also, the residual compressive strength (Compression After Impact) of the laminates made with these resins is presented.
The application of error-sensitive testing strategies to debugging

Program errors can be considered from two perspectives -- cause and effect. The goal of program testing is to detect errors by discovering their effects, while the goal of debugging is to search for the associated cause. In this paper, we explore ways in which some of the results of testing research can be applied to the debugging process. In particular, computation testing and domain testing, which are two error-sensitive test data selection strategies, are described. Ways in which these selection strategies can be used as debugging aids are then discussed.
Revisiting the Hispanic mortality advantage in the United States: the role of smoking.

More than three decades of health disparities research in the United States has consistently found lower adult mortality risks among Hispanics than their non-Hispanic white counterparts, despite lower socioeconomic status among Hispanics. Explanations for the “Hispanic Paradox” include selective migration and cultural factors, though neither has received convincing support. This paper uses a large nationally representative survey of health and smoking behavior to examine whether smoking can explain life expectancy advantage of Hispanics over US-born non-Hispanics whites, with special attention to individuals of Mexican origin. It tests the selective migration hypothesis using data on smoking among Mexico-to-US migrants in Mexico and the United States. Both US-born and foreign-born Mexican-Americans exhibit a life expectancy advantage vis-a-vis whites. All other Hispanics only show a longevity advantage among the foreign-born, while those born in the United States are disadvantaged relative to whites. Smoking-attributable mortality explains the majority of the advantage for Mexican-Americans, with more than 60% of the gap deriving from lower rates of smoking among Mexican-Americans. There is no evidence of selective migration with respect to smoking; Mexicans who migrate to the US smoke at similar rates to Mexicans who remain in Mexico, with both groups smoking substantially less than non-Hispanic whites in the US. The results suggest that more research is needed to effectively explain the low burden of smoking among Mexican-Americans in the United States.
Risk factors for urinary tract infections in colorectal compared with vascular surgery: a need to review current present-on-admission policy?

Background To reduce cost, the Centers for Medicare and Medicaid Services adopted a nonpayment policy for "reasonably preventable events" including hospital acquired urinary tract infection (UTI). Type of operation a patient undergoes could be an inevitable nonmodifiable risk factor in the development of UTI. Study Design Using Participant User File for National Surgical Quality Improvement Program (NSQIP) data from 2005 to 2007, vascular and colorectal cases were identified using CPT codes and analyzed for UTI incidence and risk factors within each group. Results We identified 30,900 colorectal cases and 39,246 vascular cases with 1,289 (4.2%) colorectal and 952 (2.4%) vascular UTI cases. A multivariate analysis of the dataset revealed colorectal procedures as an independent risk factor for the development of UTI. Subset analysis revealed this significant relationship only for patients with low ( Conclusions Current policy to reward higher quality fails to differentiate between UTI that may be preventable versus one likely due to nonmodifiable risk factors. Colorectal surgery is more likely to result in higher rates of UTI in comparison with vascular surgery, which may be related to type and complexity of a procedure. Further research needs to be done to change this policy to take into account this nonmodifiable risk factor.
Useful applications of closed-loop signal shaping controllers

Input shaping is a well-established open-loop technique used for reducing the vibratory response of dynamic systems. Some researchers have investigated the stability and utility of using this technique within a feedback control loop. The main contribution of the prior investigations was to identify stable configurations of in-the-loop input shaping systems. This paper identifies three promising applications of the stable controllers. Performance comparisons are made between the in-the-loop input shaping systems and more conventional feedback control strategies. Experimental results from a 10-ton industrial bridge crane, a portable bridge crane, and a portable tower crane are used to demonstrate the utility of the closed-loop input shaping control architecture.
Approximate Screening Functions in Metals

A variational principle is used to "solve" an approximate integral equation for the screening functions of the electron gas. It is shown that the simplest possible trial function gives a solution to the equation for the dielectric constant which is exact in both the limits of small and large momentum transfers. The results are compared with other calculations. It is shown that the approximation developed recently by Kleinman is quite good in the static large-$k$ limit, but otherwise incorrect. The dielectric constant derived from the variational calculation is used to derive an expression for the ground-state energy; this expression is similar in its essential features to the interpolation schemes of Hubbard and of Nozi\`eres and Pines, even though the Hubbard approximation considerably underestimates the exchange enhancement of the vertex function at large $k$. Finally, it is suggested that similar variational principles may have other uses, as in the paramagnon problem.
Multi-Gaussian beams: a super-Gaussian alternative

ABSTRACT: The multi-Gaussian beam shape is proposed as a model for aperture functions and laser beam profiles which have anearly flat top, but whose sides decrease continuously. Beams and apertures ofthis type represent a simple, elegant, andintuitive alternative to super-Gaussian beams. The design of lasers that have these beams as its eigenmodes is discussed.Such laser resonators would have increased energy extraction from the laser amplifier.Keywords: Gaussian beams, propagation, diffraction, super-Gaussian beams, laser resonators, optical systems, high powerlasers 1. INFRODUCTION A top-hat laser beam profile is highly sought in a wide variety of applications. However, this top-hat profile, represented bya circ function, destabilizes as it propagates, leading to an undesirable ringing phenomena. This is well known from thestudy ofdiffraction ofa plane wave by a circular hole. The oft-used Gaussian-profiled beam has the advantage of retainingits smooth shape as it propagates through free space. The disadvantage ofthe Gaussian shape is that the low intensity at thesides ofthe beam does not make it a good enough approximation to the desired top-hat shape. For example, the Gaussianshape is much less efficient at extracting energy from a laser amplifier than the top-hat.A popular alternative to the Gaussian and the circ profiles is the super-Gaussian profile. However, the evaluation ofthe free space propagation ofthe field with this profile cannot be performed in a closed form, and numerical techniques arerequired. This difficulty would be alleviated ifone could write the beam profile as a sum ofGaussian beams, as thepropagation characteristics ofGaussian beams are well known. With this and acoustics applications in mind, Wen andBreazeale proposed a beam profile that consists ofa sum ofsuperimposed complex Gaussian [1]. Their proposed beamshave the following form:
Implementation of dual-energy technique for virtual monochromatic and linearly mixed CBCTs

Purpose: To implement dual-energy imaging technique for virtual monochromatic (VM) and linearly mixed (LM) cone beam CTs (CBCTs) and to demonstrate their potential applications in metal artifact reduction and contrast enhancement in image-guided radiation therapy (IGRT). Methods: A bench-top CBCT system was used to acquire 80 kVp and 150 kVp projections, with an additional 0.8 mm tin filtration. To implement the VM technique, these projections were first decomposed into acrylic and aluminum basis material projections to synthesize VM projections, which were then used to reconstruct VM CBCTs. The effect of VM CBCT on the metal artifact reduction was evaluated with an in-house titanium-BB phantom. The optimal VM energy to maximize contrast-to-noise ratio (CNR) for iodine contrast and minimize beam hardening in VM CBCT was determined using a water phantom containing two iodine concentrations. The LM technique was implemented by linearly combining the low-energy (80 kVp) and high-energy (150 kVp) CBCTs. The dose partitioning between low-energy and high-energy CBCTs was varied (20%, 40%, 60%, and 80% for low-energy) while keeping total dose approximately equal to single-energy CBCTs, measured using an ion chamber. Noise levels and CNRs for four tissue types were investigated for dual-energy LM CBCTs in comparison with single-energy CBCTs at 80, 100, 125, and 150 kVp. Results: The VM technique showed substantial reduction of metal artifacts at 100 keV with a 40% reduction in the background standard deviation compared to a 125 kVp single-energy scan of equal dose. The VM energy to maximize CNR for both iodine concentrations and minimize beam hardening in the metal-free object was 50 keV and 60 keV, respectively. The difference of average noise levels measured in the phantom background was 1.2% between dual-energy LM CBCTs and equivalent-dose single-energy CBCTs. CNR values in the LM CBCTs of any dose partitioning are better than those of 150 kVp single-energy CBCTs. The average CNR for four tissue types with 80% dose fraction at low-energy showed 9.0% and 4.1% improvement relative to 100 kVp and 125 kVp single-energy CBCTs, respectively. CNRs for low-contrast objects improved as dose partitioning was more heavily weighted toward low-energy (80 kVp) for LM CBCTs. Conclusions: Dual-energy CBCT imaging techniques were implemented to synthesize VM CBCT and LM CBCTs. VM CBCT was effective at achieving metal artifact reduction. Depending on the dose-partitioning scheme, LM CBCT demonstrated the potential to improve CNR for low contrast objects compared to single-energy CBCT acquired with equivalent dose.
Are the Institute of Medicine recommendations for gestational weight gain appropriate for adolescents

Objective To explore the use of Centers for Disease Control and Prevention body mass index percentiles for adolescents to classify adolescents for gestational weight gain recommendations. Design A descriptive study using secondary data analysis. Setting Memphis, Tennessee. Participants Three hundred forty‐seven primiparous Black adolescents, aged 12 to 19 years, who delivered full‐term infants. Main outcome measures Adult and adolescent body mass index categories, gestational weight gain patterns, and neonatal birthweight. Results Adolescents, especially smaller adolescents, were misclassified when the current Institute of Medicine adult body mass index categories were used to classify them for gestational weight gain when compared to the use of the Centers for Disease Control and Prevention body mass index percentiles for adolescents as a gestational weight gain classification schema. Mean neonatal birthweights were similar no matter which schema was used. A large proportion of adolescents gained more than is recommended by the Institute of Medicine. Conclusions The current gestational weight gain recommendations based on adult body mass index categories may not be sufficiently specific to attain the best maternal and neonatal outcomes for adolescents. Creation of gestational weight gain recommendations based on the Centers for Disease Control and Prevention body mass index percentiles would potentially assist clinicians in counseling adolescents regarding gestational weight gain.
Determination of eicosanoids, phospholipids and related compounds by thermospray liquid chromatography-mass spectometry

Abstract Thermospray mass spectrometry has proven to be a useful technique for analyzing various biological compounds including eicosanoids phospholipids. Molecular ions as well as fragment ions which reveal useful structural information are produced for underivatized eicosanoids phospholipids using filament-off or filament-on thermospray mass spectrometry, respectively. In conjunction with on-line chromatographic separation, complex mixtures of biological samples can be rapidly analyzed with great reliability. Data will be presented concerning the analysis of prostaglandins other eicosanoids molecular species of phospholipids as well as the application of these methodologies to complex biological samples.
Actin filament patterns in mouse lens epithelium: a study of the effects of aging, injury, and genetics

Using mainly fluorescence microscopy after rhodamine-phalloidin staining, the F-actin distribution in the mouse lens epithelium was studied with regard to the effects of age, genetic strain, and mechanical injury. These studies have revealed that aside from its association with the plasma membrane the structural organization of F-actin in the mouse lens epithelium in situ is characterized by two major configurations: (1) a filamentous arrangement in such patterns as stress fibers, polygonal arrays (PAs), and meshworks, and (2) a highly concentrated structure called a sequestered actin bundle (SAB). The aging study indicated that the SAB is a consistent character in C57BL/6 mice from the age of 5 wk on, but not in CF1 mice. The size and shape of the SAB change gradually with age as inferred from two-dimensional measurements. The genetic study on the SAB character using hybrids and congenic strains showed that it is inherited as a Mendelian dominant, probably multigenic mode. Finally, the injury study revealed a structural modification in cells around the wound, including flattening of cells at the edge and extension of processes into the wound space. In the rest of the epithelium, injury amplified membrane infolding and fluorescence of polygonal arrays but diminished the size and fluorescence intensity of SABs. These changes are thought to be correlated with wound repair involving cell division and migration. These studies illustrate the variability in F-actin expression in situ in lens epithelial cells that can be induced by intrinsic and extrinsic factors.