cssi/SciSciGPT-SciSciNet huggingface dataset:
Moduli Spaces of Sheaves on Surfaces: Hecke Correspondences and Representation Theory

In modern terms, enumerative geometry is the study of moduli spaces: instead of counting various geometric objects, one describes the set of such objects, which if lucky enough to enjoy good geometric properties is called a moduli space. For example, the moduli space of linear subspaces of \({\mathbb {A}}^n\) is the Grassmannian variety, which is a classical object in representation theory. Its cohomology and intersection theory (as well as those of its more complicated cousins, the flag varieties) have long been studied in connection with the Lie algebras \(\mathfrak {sl}_n\).
Choice sets for spatial discrete choice models in data rich environments

Abstract Failure to properly specify an agent's choice set in discrete choice models will generate biased parameter estimates resulting in inaccurate behavioral predictions as well as biased estimates of policy relevant metrics. We propose a method of constructing choice sets by sampling from specific points in space to model agent behavior when choice alternatives are unknown to the researcher, potentially infinite, and differ according to spatial and temporal factors. Using Monte Carlo analysis we compare the performance of this point-based sampling method to the commonly used approach of spatially aggregating choice alternatives. We then apply these alternative approaches to modelling location choice in the Pacific groundfish trawl fishery which has a complex spatial choice structure. Both the Monte Carlo and application results provide considerable support for the efficacy of the point-based approaches.
STEAM Maker Education: Conceal/Reveal of Personal, Artistic and Computational Dimensions in High School Student Projects

Much of maker education’s expansion has focused on STEM (science, technology, engineering, mathematics) learning, leaving out equally promising opportunities for integrating arts learning. In this paper we share findings from a project in which high school students created electronic-textiles-based art representing features of a community important to them as a part of an elective high school computer science class. We addressed the following research questions: 1) What kinds of personal and community meanings did students convey through their maker projects? 2) How did students engage with artistic dimensions in their projects? 3) How did coding interactive features support students’ artwork? Drawing on daily observations, pre/post interviews, and documentation of students’ artifacts (photographs of in-process designs, design notebooks, and artist statements), we developed four case studies of students as they made art representing their communities using electronic-textiles as their primary medium. Our findings reveal how making became a means of personal, artistic expression with quite literal layering of coded meanings, and how maker activities can integrate art. In the discussion we consider the opportunities for authentic artistic expression in maker education by distinguishing the difference between craft and art in a maker education context. We consider the ways in which these ideas have implications for equity, pedagogy, and future research.
Portrait of the Mathematician as a New Mother

Devin at three weeks taught me:there is more than one face.And given two objects,they probably don’t touch.Devin at three months taught me:the room is not symmetric.And six months, Devinwe are all ...
Molecular origins of APOBEC-associated mutations in cancer

The APOBEC family of cytidine deaminases has been proposed to represent a major enzymatic source of mutations in cancer. Here, we summarize available evidence that links APOBEC deaminases to cancer mutagenesis. We also highlight newly identified human cell models of APOBEC mutagenesis, including cancer cell lines with suspected endogenous APOBEC activity and a cell system of telomere crisis-associated mutations. Finally, we draw on recent data to propose potential causes of APOBEC misregulation in cancer, including the instigating factors, the relevant mutator(s), and the mechanisms underlying generation of the genome-dispersed and clustered APOBEC-induced mutations.
Symptomatic cervical spinal stenosis in spastic cerebral palsy.

AIM To describe the prevalence of symptomatic cervical spinal stenosis (CSS) in spastic cerebral palsy (CP) and associated characteristics. METHOD This cross-sectional study of adults (>18y) with CP (2006-2016) at a single institution compared the patient characteristics (demographics, comorbidities, surgical history, medications, Gross Motor Function Classification System [GMFCS] level, and CP type) of patients with and without CSS. RESULTS Of 424 patients (mean age 33y 4mo, SD 13y 6mo, range 18-78y; 225 females, 199 males), 32 patients (7.5%) had symptomatic CSS. GMFCS levels in the study cohort were distributed as follows: level I, 25%; level II, 25%; level III, 22%; level IV, 19%; level V, 9%. Twenty-five out of 32 (78.1%) patients had spastic CP, two (6.3%) had dystonic CP, and one (3.1%) had mixed characteristics. Individuals with CSS were older (mean age 54y 6mo, SD 10y 5mo vs mean age 31y 7mo, SD 12y 1mo, p<0.05) and had a higher body mass index (26.1, SD 4.8 vs 23.4, SD 6.2, p<0.05) than those without CSS. Presentations included upper-extremity symptoms (73%), ambulation decline (70%), neck pain (53%), and incontinence (30%). Common stenosis levels were C5-C6 (59%), C4-C5 (56%), and C6-C7 (53%). INTERPRETATION Symptomatic CSS was identified in 7.5% of this adult cohort during the 2006 to 2016 period. Diagnosis in CP is difficult due to impaired communication and pre-existing gait abnormalities and spasticity. Given the high prevalence of symptomatic CSS in adults, we propose developing screening guidelines. Physicians must maintain a high level of suspicion for CSS if patients present with changes in gait or spasticity.
Gender-Affirming Hormone Therapy and Bone Health: Do Different Regimens Influence Outcomes in Transgender Adults? A Narrative Review and Call for Future Studies.

Background Gender-affirming hormone therapy (GAHT) influences bone health in transgender individuals. Several hormone preparations and administration routes are available for GAHT, but no studies have compared clinical and laboratory bone health measures across different GAHT regimens. Content We searched PubMed (MEDLINE), Embase, and Google Scholar for studies measuring bone turnover markers and bone mineral density before and during GAHT in transgender adults. We summarized bone health data by hormone type and administration route (estrogen or testosterone; oral, transdermal/percutaneous, intramuscular). Among trans women, we also examined outcomes among regimens containing different adjunctive agents (antiandrogens or gonadotropin-releasing hormone analogs). Summary Most hormone preparations maintained or increased areal bone mineral density among trans adults taking GAHT for at least 12 months from baseline. Different bone turnover markers were measured across studies, and we were unable to compare or comment on the direct influence of selected hormone preparations on these clinical laboratory measures. Larger and uniformed studies are needed to measure volumetric bone mineral density and biomarkers of bone metabolism in trans adults taking standardized GAHT regimens.
Embodied Liberation in Participatory Theory and Buddhist Modernism Vajrayāna

This article explores body constructs along the descending, ascending, and extending body-soteriological pathways, as well as it lays the foundation to identify their potential for transbody and transpersonal transformation. Insights are provided on the nexus of pluralistic body constructs using Jorge Ferrer’s participatory theory juxtaposed with Buddhist Modernism focused on Vajrayāna Indo-Tibetan Buddhism. An exuberant richness of physical and metaphysical bodies has been recognized in both Vajrayāna Buddhism and participatory theory. In Vajrayāna, the body is central to liberation and viewed as the culmination of immanence, transcendence, and expansion. In participatory theory, the body is viewed as equal to vital, heart, mind, and consciousness as part of an integrated larger whole. Embodiment, disembodiment, and body awareness are critically discussed, and special attention is given to the implications of these two contrasting views and the potential of practices from both approaches to ameliorate disembodiment and foster transbody and transpersonal transformation.
A Hermite Method with a Discontinuity Sensor for Hamilton-Jacobi Equations.

We present a Hermite interpolation based partial differential equation solver for Hamilton-Jacobi equations. Many Hamilton-Jacobi equations have a nonlinear dependency on the gradient of the solution, which gives rise to discontinuities in the gradient of the solution, resulting in kinks in the solution itself. We built our solver with two goals in mind: 1) high order accuracy in smooth regions and 2) sharp resolution of kinks. To achieve this, we use Hermite interpolation with a smoothness sensor. The degrees-of-freedom of Hermite methods are tensor-product Taylor polynomials of degree $m$ in each coordinate direction. The method uses $(m+1)^d$ degrees of freedom per node in $d$-dimensions and achieves an order of accuracy $(2m+1)$ when the solution is smooth. To obtain sharp resolution of kinks, we sense the smoothness of the solution on each cell at each timestep. If the solution is smooth, we march the interpolant forward in time with no modifications. When our method encounters a cell over which the solution is not smooth, it introduces artificial viscosity locally while proceeding normally in smooth regions. We show through numerical experiments that the solver sharply captures kinks once the solution losses continuity in the derivative while achieving $2m+1$ order accuracy in smooth regions.
Barring Married Same-Sex Couples from Joint Adoption: Comparative Perspectives and the Case of Taiwan

English abstract: Taiwan is the first country in Asia to legalize same-sex marriage, but it forbids married same-sex couples from jointly adopting children. This article examines this restriction through the lens of comparative law, which brings into focus two main insights. First, we see that, out of all countries that have legalized same-sex marriage, Taiwan is one of only two that bar married same-sex couples from joint adoption. As this article will explain, the fact that Taiwan’s policy is so anomalous should spur skepticism of the policy’s appropriateness. Second, judicial opinions from around the world contain persuasive reasoning that further calls into question Taiwan’s treatment of married same-sex couples. This article explains that these findings, taken together, cast enormous doubt on the constitutionality of Taiwan’s exclusionary adoption policy. Chinese abstract: 臺灣雖然是亞洲第一個承認同性婚姻的國家，但其禁止同性婚姻配偶共同收養小孩。本文從比較法的觀點檢視前開限制，得出以下兩個觀察：首先，在所有承認同性婚姻的國家之中，臺灣是限制共同收養中僅有的兩個國家。本文認為此反常的事實將造成此政策是否合適的質疑。再者，全球關於同性婚姻的司法論證，皆進一步質疑前開限制的正當性。前開兩個觀察皆顯示了臺灣對於共同收養的限制有違憲的疑慮。
Development of an Integrated Linkage Map

Linkage maps have become widespread and essential genetic tools for crop improvement and other biological studies. Indeed, assembling a linkage map is now possible, even for species, cultivated or wild, that do not have a long and intensive history of genetic research. Previously, linkage maps existed only for a few experimental organisms, such as Drosophila, maize (Zea mays L.), and tomato (Lycopersicon esculentum L.). This change is due to the development of molecular marker technologies that have led to a large increase in the number of polymorphic loci within any given segregating population. Before the advent of molecular markers, phenotypic markers were generally used. Accumulating enough of these markers in the same population was time-consuming and difficult (because of the often-deleterious nature of these markers or epistatic interactions). Alternatively, results from different segregating populations had to be combined leading to uncertainties as to allelism and actual map location.
Biodegradable nano-films for capture and non-invasive release of circulating tumor cells

Selective isolation and purification of circulating tumor cells (CTCs) from whole blood is an important capability for both clinical medicine and biological research. Current techniques to perform this task place the isolated cells under excessive stresses that reduce cell viability, and potentially induce phenotype change, therefore losing valuable information about the isolated cells. We present a biodegradable nano-film coating on the surface of a microfluidic chip, which can be used to effectively capture as well as non-invasively release cancer cell lines such as PC-3, LNCaP, DU 145, H1650 and H1975. We have applied layer-by-layer (LbL) assembly to create a library of ultrathin coatings using a broad range of materials through complementary interactions. By developing an LbL nano-film coating with an affinity-based cell-capture surface that is capable of selectively isolating cancer cells from whole blood, and that can be rapidly degraded on command, we are able to gently isolate cancer cells and recover them without compromising cell viability or proliferative potential. Our approach has the capability to overcome practical hurdles and provide viable cancer cells for downstream analyses, such as live cell imaging, single cell genomics, and in vitro cell culture of recovered cells. Furthermore, CTCs from cancer patients were also captured, identified, and successfully released using the LbL-modified microchips.
The Opera of Medicine

The narrative The Opera of Medicine examines the mysterious relational aspects of the physician–patient connection. This mystery seems to arise out of some random and not-so-random happenstances, all of which reflect at some basic level the wholeness implicit in not only the patient but also the physician. This wholeness includes their histories, passions, splendors, and sufferings. Sister Josepha and her closest friend Norma meet Dr. Krasner in a setting designed to cultivate attention and awareness to the present moment. Within those early moments, and from that point forward, the past, present, and future of the doctor and the patients are interwoven, and the possibility for mutual healing arises naturally out of that fabric. The reader may wonder at moments who is healing whom? In the end, healing becomes a relational process, whose foundation is love.
CD94/NKG2A expression is associated with proliferative potential of CD8 T cells during persistent polyoma virus infection

Memory CD8 T cells comprise a critical component of durable immunity because of their capacity to rapidly proliferate and exert effector activity upon Ag rechallenge. During persistent viral infection, memory CD8 T cells repetitively encounter viral Ag and must maintain a delicate balance between limiting viral replication and minimizing immunopathology. In mice infected by polyoma virus, a natural mouse pathogen that establishes long-term persistent infection, the majority of persistence-phase antiviral CD8 T cells express the inhibitory NK cell receptor CD94/NKG2A. In this study, we asked whether CD94/NKG2A expression is associated with Ag-specific recall of polyoma virus-specific CD8 T cells. During the persistent phase of infection, polyoma virus-specific CD8 T cells that express CD94/NKG2A were found to preferentially proliferate; this proliferation was dependent on cognate Ag both in vitro and in vivo. In addition, CD94/NKG2A(+) polyoma-specific CD8 T cells have a markedly enhanced capacity to produce IL-2 upon ex vivo Ag stimulation compared with CD94/NKG2A(-) polyoma-specific CD8 T cells. Importantly, CD94/NKG2A(+) anti-polyoma virus CD8 T cells appear to be essential for Ag-specific recall responses in mice persistently infected by polyoma virus. Because of its higher proliferative potential and capacity to produce IL-2, we propose that the CD94/NKG2A(+) subpopulation represents a less differentiated state than the CD94/NKG2A(-) subpopulation. Identification of proliferation-competent subpopulations of memory CD8 T cells should prove valuable in designing therapeutic vaccination strategies for persistent viral infections.
White Dwarfs in Close Binaries in the Extreme Ultraviolet Explorer All-Sky Survey

We examine the orbital and physical properties of the EUVE sample of white dwarfs found in binary systems with short orbital periods (∼ 1d). These systems, consisting of a hot white dwarf and a main sequence star, are recent survivors of a common envelope phase responsible for dramatic momentum losses and orbital shrinkage. The white dwarfs in close binaries also constitute a surprisingly large fraction of the total sample of white dwarfs discovered in the EUVE all-sky survey. Most secondary stars are M-dwarfs, with an average mass of > 0.5 M⊙, and comparisons with some simulated samples of close binaries suggest that many more systems with very low mass secondary stars (< 0.3 M⊙) remain to be discovered.
Specific heat of 4He confined to 9869 Å planar geometry

Abstract We report new data for 4 He confined between two silicon wafers spaced 9869 A apart. This spacing complements a series of previous measurements which now span a factor of 20 between the smallest and largest confinements. These new data allow us to further check scaling predictions. We find, as reported with previous data, that the present data scale well except near the heat capacity maximum, and below into the superfluid region.
Bootstrapping training-data representations for inductive learning: a case study in molecular biology

This paper describes a "bootstrapping" approach to the engineering of appropriate training-data representations for inductive learning. The central idea is to begin with an initial set of human-created features and then generate additional features that have syntactic forms that are similar to the human-engineered features. More specifically, we describe a two-stage process for the engineering of good representations for learning: first, generating by hand (usually in consultation with domain experts) an initial set of features that seem to help learning, and second, "bootstrapping" off of these features by developing and applying operators that generate new features that look syntactically like the expert-based features. Our experiments in the domain of DNA sequence identification show that an initial successful human-engineered representation for data can be expanded in this fashion to yield dramatically improved results for learning.
Deficiency Mapping of Quantitative Trait Loci Affecting Longevity in Drosophila melanogaster

In a previous study, sex-specific quantitative trait loci (QTL) affecting adult longevity were mapped by linkage to polymorphic roo transposable element markers, in a population of recombinant inbred lines derived from the Oregon and 2b strains of Drosophila melanogaster. Two life span QTL were each located on chromosomes 2 and 3, within sections 33E-46C and 65D-85F on the cytological map, respectively. We used quantitative deficiency complementation mapping to further resolve the locations of life span QTL within these regions. The Oregon and 2b strains were each crossed to 47 deficiencies spanning cytological regions 32F-44E and 64C-76B, and quantitative failure of the QTL alleles to complement the deficiencies was assessed. We initially detected a minimum of five and four QTL in the chromosome 2 and 3 regions, respectively, illustrating that multiple linked factors contribute to each QTL detected by recombination mapping. The QTL locations inferred from deficiency mapping did not generally correspond to those of candidate genes affecting oxidative and thermal stress or glucose metabolism. The chromosome 2 QTL in the 35B-E region was further resolved to a minimum of three tightly linked QTL, containing six genetically defined loci, 24 genes, and predicted genes that are positional candidates corresponding to life span QTL. This region was also associated with quantitative variation in life span in a sample of 10 genotypes collected from nature. Quantitative deficiency complementation is an efficient method for fine-scale QTL mapping in Drosophila and can be further improved by controlling the background genotype of the strains to be tested.
Optically Assisted High-Speed, High Resolution Analog-to-Digital Conversion

An approach that modifies an analog fiber optic link with a recirculating optical loop as a means to realize a high-speed, high-resolution Analog-to-Digital Converted (ADC) is presented. The loops stores a time-limited microwave signal so that it may be digitized by using a slower, conventional electronic ADC. Detailed analytical analysis of the dynamic range and noise figure shows that under appropriate conditions the microwave signal degradation is sufficiently small so as to allow the digitization of a multi-gigahertz signal with a resolution greater than 10 effective bits. Experimental data is presented which shows that a periodic extension of the input signal can be sustained for well over one hundred periods that in turn suggests an electronic ADC speed-up factor of over 100. The data also shows that polarization effects must be carefully managed to inhibit the loops tendency to lase even though the loop itself contains no frequency-selective elements.
Race and Ethnic Variations in the Education-Control-Distress Model

Objective Research shows that education favors mental health, in part, because it helps to develop a greater sense of control. To this point, however, it is unclear whether this process varies according to race and ethnicity. Methods Building on previous research, we use data collected from a large probability sample of Texas adults to test the extent to which the education-control-distress (E-C-D) model varies across three race and ethnic groups, including whites, blacks, and Mexican Americans. Results The results of our simple mediation analyses validate the E-C-D model for each race/ethnic group. Our moderated mediation analyses suggest that the indirect effect of education on psychological distress through the sense of control is comparable across race/ethnic groups. Conclusion The mediating influence of the sense of control does not appear to vary according to the three race/ethnic groups included in the study.
The results of radiotherapy for orbital pseudotumor.

Between January 1982 and March 1987, 23 patients (26 orbits) were treated for orbital pseudotumor with radiation therapy at the Department of Radiation Oncology, Hospital of the University of Pennsylvania. The patients were referred for clinical relapse after steroid taper in 70%, no response to steroids in 17%, and no steroid treatment (refused or contraindicated) in 13%. Presenting symptoms/signs included soft tissue swelling in 92% of orbits, pain in 92%, proptosis in 85%, and extraocular muscle dysfunction or ptosis in 69%. Decreased visual acuity was seen in only 19% of orbits. Biopsy was performed in nine patients. Treatment consisted of 2000 cGy in 2 weeks in 10 fractions for all patients. Median follow-up was 41 months, with a mean of 53 months, and a range of 21-92 months. Complete response was documented in 87% of orbits with soft tissue swelling, 82% with proptosis, 78% with extraocular muscle dysfunction, and 75% with pain. Of the five patients with visual acuity defects, three experienced complete recovery. There was no difference in complete response in patients biopsied versus those not biopsied. Overall, 17 orbits have remained in complete orbital response with no further steroid requirement (66%). Three orbits suffered local relapse at some point following radiation therapy and were retreated with steroids. These three orbits had durable local control off steroids at last follow-up (11%). Therefore, 77% of orbits attained durable local control and were steroid independent with radiation therapy alone or radiation therapy followed by steroids for relapse. Only one patient developed systemic lymphoma with follow-up. No pretreatment clinical factor reached statistical significance with respect to prognosis following radiation therapy at the less than or equal to .05 level. There were no significant acute or chronic side effects secondary to treatment. Steroids should continue to be first line treatment for orbital pseudotumor, but radiation therapy has a well-defined role in cases of steroid failure or in patients unable to tolerate steroid therapy.
A unified and efficient approach for determining Thevenin (Norton) equivalent circuits

A unified and efficient approach for the determination of the Thevenin (Norton) equivalent circuit is presented, in which two parameters of the Thevenin (Norton) equivalent circuit can be obtained simultaneously and systematically, and it is not required to set all independent sources to zero. >
Segmentation of scanned document images for efficient compression

A scanned, complex document image may be composed of text, graphics, halftones, and pictures, whose layout is unknown. In this paper, we propose a novel segmentation scheme for scanned document images that facilitates their efficient compression. Our scheme segments an input image into binarizable components and no-binarizable components. By a binarizable component we mean that the region can be represented by no more than two gray levels (or colors) with acceptable perceptual quality. A non-binarizable component is defined as region that has to be represented by more than two gray levels (or colors) with acceptable perceptual quality. Once the components are identified, the binarizable components can be thresholded and compressed as a binary image using an efficient binary encoding scheme together with the gray values represented by the black and white pixels of the binary image. The non-binarizable components can be compressed using another suitable encoding scheme.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Disciplining and popularizing: Evolution and its publics from the modern synthesis to the present

This paper serves as an introduction to a special collection of papers exploring the centrifugal and centripetal forces in the process of disciplining and popularizing the science of evolution in the period preceding and after the modern synthesis of evolution.
Experimental studies of a coronavirus and coronavirus-like agent in a barrier-maintained feline breeding colony

Minimal-disease (MD) cats raised in a barrier-maintained feline breeding colony routinely become coronavirus (CV) antibody-positive at 5–8 weeks of age and remain seropositive indefinitely. In addition, they shed coronavirus-like particles (CVLPs) in their feces which are morphologically distinct from “typical” coronaviruses. Oronasal, intraperitoneal, intraduodenal, and intravenous inoculations of CVLPs were uniformly unsuccessful in the seroconversion of cats to CV, whereas subsequent prolonged close contact with colony cats did result in seroconversion. Such evidence indicates that MD cats in this barrier colony are infected with at least two non-cross-reactive agents: (1) feline enteric CVLPs, which are shed in feces and are morphologically and antigenically distinct from established coronaviruses (CVs), and (2) a virus which is antigenically cross-reactive with CVs, but which is apparently shed by some route other than the lower gastrointestinal tract.
A Review of Enrico Moretti's The New Geography of Jobs

Why is prosperity distributed so unevenly across America's metropolitan areas? While population growth has gone disproportionately towards the Sunbelt, high-skill areas have experienced the strongest income growth since 1970. Gaps between more and less educated areas were modest forty years ago, but they have become quite large, and far larger than would be predicted solely by the general rise in the returns to skill. Unemployment rates during the recent recession were also strongly correlated with area level education. This essay reviews Enrico Moretti's The New Geography of Jobs , which both describes and explains these significant regional trends
A film boiling model for cryogenic chilldown at low mass flux inside a horizontal pipeline

A film boiling heat transfer model is developed for cryogenic chilldown at low mass flux inside a horizontal pipeline. It incorporates the stratified flow structure and is based on conservation principles of mass, momentum, and energy. Simplifying assumptions lead to an expression for the local film boiling heat transfer coefficient which varies with the azimuthal angle. The efficacy of the model is assessed by comparing the predicted wall temperature histories with those measured at several azimuthal positions and various mass fluxes. Good agreement is observed at low flux, G = 13–54 kg/m2 s.
Knowing the Standard American Diet by Its Fruits: Is Unrestrained Omnivorism Spiritually Beneficial?

This essay aims to challenge the standard [North] American diet’s (SAD) default status in church and among North American Christians generally. It attempts to allay some common concerns about the suitability of food ethics as a topic for serious Christian discernment, and argues that SAD is not spiritually beneficial, drawing support from five traditional sources for Christian moral deliberation, including and especially general revelation and discernment of the fruits of the spirit.
Petrology of some lithic fragments from Luna 20.

Microscopic and electron microprobe studies were made of polished thin sections of part of a 30-mg sample of 250- to 500-micron lunar soil returned by Luna 20 from a point between Mare Fecunditatis and Mare Crisium. Very fine-grained lithic (crystalline) rock fragments, composing about one-fifth of the total sample, have mineralogical compositions equivalent to various types of gabbro, anorthositic gabbro, gabbroic anorthosite, and troctolite, with minor basalt. The textures now observed in these fragments are in large part metamorphic. Twenty-seven electron microprobe analyses of minerals from these fragments are presented, including olivine, plagioclase, pyroxene, spinel, nickel-iron, and a Zr-Ti-REE mineral possibly similar to 'phase B' of Lovering and Wark (1971). Analyses of seven melt inclusions and 28 defocused beam analyses of lithic fragments are also given. Some of the fragments contain 'gas' inclusions which, along with the fine grain size, are believed to indicate final crystallization under low pressure near surface conditions.
Driver experience with antilock brake systems

Antilock brakes provide the capability for shorter stopping distances and the ability to steer and maintain control during hard braking, especially on wet and slippery surfaces. Owners of late model cars equipped with antilock brakes were surveyed in North Carolina and Wisconsin regarding their experiences with antilocks. The survey results indicated that more than 50% of the drivers in North Carolina and 40% in Wisconsin incorrectly indicated how to brake a car in an emergency situation on wet and slippery pavements in a way that will effectively activate the antilock feature. More drivers in Wisconsin than in North Carolina reported that their cars' antilock feature had been used, but more than 33% of the Wisconsin drivers and 62% of North Carolina drivers said they had never used the antilock feature of their cars' brakes.
The Pathophysiology of Cholesteatoma

The pathogenesis of middle ear cholesteatoma continues to be highly debated. In recent years, there has been a substantial improvement in the understanding of the pathophysiology of this disease. This chapter provides a summary of the history and evolution of cholesteatoma and a review of the recent literature that pertains to the pathophysiology of congenital and acquired cholesteatoma. An emphasis is placed on the mechanism of osteolysis and the factors predictive of aggressiveness and recidivism.
The implication of sensitivity analysis on the safety and delayed-neutron parameters for fast breeder reactors

Abstract The delayed-neutron energy spectra for LMFBRs are not as well known as those for LWRs. These spectra are necessary for kinetics calculations which play an important role in safety and accident analyses. A sensitivity analysis was performed to study the response of the reactor power and power density to uncertainties in the delayed-neutron spectra during a rod-ejection accident. The accidents studied were central control-rod ejections with ejection times of 2, 10 and 30s. A two-energy group and two-precursor group model was formulated for the International Nuclear Fuel Cycle Evaluation (INFCE) reference design MOX-fueled LMFBR. The sensitivity analysis is based on the use of adjoints so that it is not necessary to repeatedly solve the governing (kinetics) equations to obtain the sensitivity derivatives. This is of particular importance when large systems of equations are used. The power and power-density responses were found to be most sensitive to uncertainties in the spectrum of the second delayed-neutron precursor group, resulting from the fission of238U, producing neutrons in the first energy group. It was found, for example, that for a rod-ejection time of 30 s, an uncertainty of 7.2% in the fast components of the spectra resulted in a 24% uncertainty in the predicted power and power density. These responses were recalculated by repeatedly solving the kinetics equations. The maximum discrepancy between the recalculated and the sensitivity analysis response was only 1.6%. The results of the sensitivity analysis indicate the need for improved delayed-neutron spectral data in order to reduce the uncertainties in accident analyses.
Toeplitz and Wiener-Hopf determinants with piecewise continuous symbols

Abstract The asymptotics for determinants of Toeplitz and Wiener-Hopf operators with piecewise continuous symbols are obtained in this paper. If Wα(σ) is the Wiener-Hopf operator defined on L2(0, α) with piecewise continuous symbol σ having a finite number of discontinuities at ξr, then under appropriate conditions it is shown that det Wα(σ) ~ G(σ)α αΣλr2K(σ), where G(σ) = exp(log σ) ( 0), λ r = ( 1 2π ) log [ σ(ξ r +) σ(ξ r −) ] and K(σ) is a completely determined constant. An analogous result is obtained for Toeplitz operators. The main point of the paper is to obtain a result in the Wiener-Hopf case since the Toeplitz case had been treated earlier. In the Toeplitz case it was discovered that one could obtain asymptotics fairly easily for symbols with several singularities if, for each singularity one could find a single example of a symbol with a singularity of that kind whose associated asymptotics were known. Fortunately in the Toeplitz case such asymptotics were known. The difficulty in the Wiener-Hopf case is that there was not a single singular case where the determinant was explicitly known. This problem was overcome by using the fact that Wiener-Hopf determinants when discretized become Toeplitz determinants whose entries depend on the size of the matrix. No theorem on Toeplitz matrices can be applied directly but these theorems are modified to obtain the desired results.
A prospective study on lipoaugmentation of the breast.

Background: The current standard for breast augmentation involves placement of an implant. As an alternative, surgeons have been exploring breast augmentation with autologous tissue in the form of injectable fat. Objectives: The authors explore the efficacy and safety of lipoaugmentation of the breast, with specific interest in volume changes, fat retention, overall aesthetic improvement, and patient satisfaction. Methods: Direct measurements, 2- and 3-dimensional images, mammograms, and magnetic resonance imaging (MRI) were obtained preoperatively from 10 consecutive patients undergoing augmentation mammaplasty with autologous fat transfer. These measurements were repeated 1 year postoperatively. Postoperative photo imaging was conducted at 3-month intervals for 1 year. Efficacy was evaluated by determining the volume of fat retention 1 year after the procedure with 3-dimensional imaging, standard breast MRI volume measurements, and subjective aesthetic comparisons. Results: The average amount of fat injected was 236 cc (90–324; SD, 69.8) in the right breast and 250 cc (90–300; SD, 65.1) in the left. The mean volume change based on 3-dimensional imaging was 85.1 cc (36% retention) for the right breast and 98.1 cc (39.2% retention) for the left. The mean volume change based on MRI measurements was 30.0 cc (39.8% change) on the right and 29.3 cc (38.1% change) on the left. Blinded observers found substantial improvement in 1 patient (10%), moderate improvement in 5 patients (50%), and minimal to no improvement in 4 (40%). Overall patient satisfaction was high, as measured by the abbreviated BREAST-Q. Radiologic abnormalities and artifacts were common and required additional imaging. Conclusions: Objective breast enlargement in this study was modest but yielded disproportionately high subjective patient satisfaction reports. Level of Evidence: 2 ![Graphic][1] [1]: /embed/inline-graphic-1.gif
Comparison of On-Call Radiology Resident and Faculty Interpretation of 4- and 16-row Multidetector CT Pulmonary Angiography with Indirect CT Venography

RATIONALE AND OBJECTIVES On-call radiology residents frequently interpret computed tomography (CT) pulmonary angiography and CT venography studies outside of routine working hours. The purpose of this study was to compare resident and faculty interpretation concordance rates and to see if concordance rates differed depending on the number of CT detectors used. MATERIALS AND METHODS The study population included 122 consecutive CT pulmonary angiography (CTPA) and CT venography (CTV) examinations performed on a four-row multidetector CT (MDCT) and 125 consecutive CTPA examinations performed using a 16-row MDCT scanner with CTV performed in 124 patients. Preliminary resident reports and final faculty reports were compared. Discrepant cases were independently reviewed by three cardiothoracic radiologists who were unaware of the initial interpretations. Interpretation concordance rates were calculated for both 4- and 16- row MDCT studies and compared using Fisher's exact test. RESULTS Resident and faculty CTPA and CTV interpretations were concordant in 80% of the 4-row cases and 94% of the 16-row cases. When comparing resident interpretation to the final expert reference standard, the corrected resident error rate was 11% and 2% for 4-row CTPA and CTV, respectively and 4% and 2% for 16-row CTPA and CTV, respectively. Overall CTPA and CTV concordance was significantly lower for 4-row MDCT (80% versus 94%, P < .001 [two-sided] by Fisher's exact test). CONCLUSIONS Radiology resident interpretation of CTPA and CTV studies demonstrates a high level of agreement with radiology faculty interpretation. Concordance rates are significantly higher for 16-row MDCT than 4-row MDCT which may be due to improved image quality.
Near-infrared optical absorption in solid DT and T2

Abstract Near-infrared optical absorption has been detected for solid DT and T 2 samples. It is suggested that this absorption is due to electrons and/or ions resulting from the radioactive decay of tritium being trapped in the solid lattice.
New Compounds: Preparation of Some Esters of Trihalogenated Alcohols

The syntheses of a number of esters of trihalogenated monohydroxy alcohols are described. The results of preliminary pharmacological tests are reported.
Rapid and efficient selection of recombinant site-directed mutants of Bradyrhizobium japonicum by colony hybridization

Due to the high incidence of spontaneous antibiotic resistance and slow growth of Bradyrhizobium japonicum strains, screening for site-directed mutants is cumbersome and time-consuming. A rapid method for selection of recombinant site-directed mutants of B. japonicum was developed. A kanamycin (Km) and a spectinomycin (Sp) cassette were each used to replace DNA fragments in the chromosome by homologous recombination. The primary new features of this method involve a simple plate selection for the antibiotic (Km or Sp) resistant mutants, then colony streaking, and lysis for DNA hybridization on a nitrocellulose filter enabling direct identification of the recombinant site-directed mutants. This method has permitted us to quickly and easily identify a large number of positive recombinant mutants from a large number of indicidual colonies. The procedure eliminates the need to first isolate genomic DNA from each mutant for Southern hybridization. All of the tested site-directed mutants from this method were confirmed to exhibit the expected mutant phenotype.
Breakdown of Dynamic Scaling in Thin Film Binary Liquids Undergoing Phase Separation

The kinetics of phase separation in thin polymer blend films displaying discrete and bicontinuous domain morphologies are examined. For discrete domains, the correlation length ξ grows as t 1 / 3 , in agreement with a coalescence model. By plotting ξ/d vs t/t i (initiation time), universal growth behavior is obtained for thickness values (d) from 1000 to 190 nm. In contrast, bicontinuous domains grow with a decreasing exponent, 0.62 to 0.28, as d decreases from 900 to 90 nm (i.e., no universal growth). This slowing down with reduced dimensionality suggests suppression of lateral hydrodynamic pumping.
Excision of group II introns as circles.

Abstract Group II introns are usually removed from precursor RNAs as lariats comprised of a circular component and a short 3′ tail. We find that group II introns can also be excised as complete circles. Circle formation requires release of the 3′ exon of a splicing substrate, apparently by a trans splicing mechanism. After 3′ exon release, the terminal uridine of the intron attacks the 5′ splice site, releasing the 5′ exon and joining the first and last intron residues by a 2′–5′ phosphodiester bond. RNA isolated from yeast mitochondria also contains circles, indicating that at least one group II intron (aI2) forms circles in vivo. Furthermore, analysis of RNA and DNA from certain mutant yeast strains shows that circular DNA introns exist and are produced by reverse transcription of RNA, rather than by ectopic homing.
An energy efficient approximate adder with carry skip for error resilient neuromorphic VLSI systems

We propose a novel approximate adder design to significantly reduce energy consumption with a very moderate error rate. The significantly improved error rate and critical path delay stem from the employed carry prediction technique that leverages the information from less significant input bits in a parallel manner. An error magnitude reduction scheme is proposed to further reduce amount of error once detected with low cost. Implemented in a commercial 90 nm CMOS process, it is shown that the proposed adder is up to 2.4× faster and 43% more energy efficient over traditional adders while having an error rate of only 0.18%. The proposed adder has been adopted in a VLSI-based neuromorphic character recognition chip using unsupervised learning. The approximation errors of the proposed adder have been shown to have negligible impact on the training process. Moreover, the energy savings of up to 48.5% over traditional adders is achieved for the neuromorphic circuit with scaled supply level. Finally, we achieve error-free operations by including a low-overhead error correction logic.
Paul Gauguin and the origin of art nouveau

Since the turn of the century there has been widespread acknowledgement that Alphonse Mucha inspired the birth of the Art Nouveau movement when he created the 'Gismonda' poster advertising the opening of the Sarah Bernhardt play of that name in Paris in 1894. At an estate sale in 1954 a small collage bearing a likeness of the Mucha 'Gismonda' was offered. It was composed of fragments of sixty postage stamps glued to a small ceramic tile. Digital computer image processing has been applied to the collage design, scratches on the handle of a walking stick in the same collection, and the Mucha poster. From comparative analyses of the enhanced 'Gismonda' images it is revealed that the little collage is considerably more detailed and compete than the Mucha 'original'. Thus, it is concluded that the poster is a hasty photographic plagiarism of the intricate collage. Further image processing of the scratches on the handle of the walking stick and the collage reveal them to conform to the famous and enigmatic 'P GO' monogram signature of the artist Paul Gauguin. Thus, it follows that the original design was created by Gauguin rather than by Mucha. It may be that while Gauguin was in Brittany recovering from injuries sustained in a brawl his former lover, Annah la Javanese, pilfered his belongings and took them with her to Paris and her next lover, photographer-designer, Alphonse Mucha, who copied the collage and offered it as the Gismonda Poster.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A medical interviewing curriculum intervention for medical students' assessment of suicide risk.

Objective Effective communication strategies are required to assess suicide risk. The authors determined whether a 2-hour simulated-patient activity during a psychiatry clerkship improved self-assessment of medical interviewing skills relevant to suicide risk-assessment.
Prostaglandin E2 acts via bone marrow macrophages to block PTH-stimulated osteoblast differentiation in vitro.

Intermittent PTH is the major anabolic therapy for osteoporosis while continuous PTH causes bone loss. PTH acts on the osteoblast (OB) lineage to regulate bone resorption and formation. PTH also induces cyclooxygenase-2 (COX-2), producing prostaglandin E2 (PGE2) that can act on both OBs and osteoclasts (OCs). Because intermittent PTH is more anabolic in Cox-2 knockout (KO) than wild type (WT) mice, we hypothesized COX-2 might contribute to the effects of continuous PTH by suppressing PTH-stimulated differentiation of mesenchymal stem cells into OBs. We compared effects of continuous PTH on bone marrow stromal cells (BMSCs) and primary OBs (POBs) from Cox-2 KO mice, mice with deletion of PGE2 receptors (Ptger4 and Ptger2 KO mice), and WT controls. PTH increased OB differentiation in BMSCs only in the absence of COX-2 expression or activity. In the absence of COX-2, PTH stimulated differentiation if added during the first week of culture. In Cox-2 KO BMSCs, PTH-stimulated differentiation was prevented by adding PGE2 to cultures. Co-culture of POBs with M-CSF-expanded bone marrow macrophages (BMMs) showed that the inhibition of PTH-stimulated OB differentiation required not only COX-2 or PGE2 but also BMMs. Sufficient PGE2 to mediate the inhibitory effect was made by either WT POBs or WT BMMs. The inhibitory effect mediated by COX-2/PGE2 was transferred by conditioned media from RANKL-treated BMMs and could be blocked by osteoprotegerin, which interferes with RANKL binding to its receptor on OC lineage cells. Deletion of Ptger4, but not Ptger2, in BMMs prevented the inhibition of PTH-stimulated OB differentiation. As expected, PGE2 also stimulated OB differentiation, but when given in combination with PTH, the stimulatory effects of both were abrogated. These data suggest that PGE2, acting via EP4R on BMMs committed to the OC lineage, stimulated secretion of a factor or factors that acted to suppress PTH-stimulated OB differentiation. This suppression of OB differentiation could contribute to the bone loss seen with continuous PTH in vivo.