cssi/SciSciGPT-SciSciNet huggingface dataset:
CellMeSH: Probabilistic Cell-Type Identification Using Indexed Literature

Abstract Single-cell RNA sequencing (scRNA-seq) is widely used for analyzing gene expression in multi-cellular systems and provides unprecedented access to cellular heterogeneity. scRNA-seq experiments aim to identify and quantify all cell types present in a sample. Measured single-cell transcriptomes are grouped by similarity and the resulting clusters are mapped to cell types based on cluster-specific gene expression patterns. While the process of generating clusters has become largely automated, annotation remains a laborious ad-hoc effort that requires expert biological knowledge. Here, we introduce CellMeSH - a new automated approach to identifying cell types based on prior literature. CellMeSH combines a database of gene-cell type associations with a probabilistic method for database querying. The database is constructed by automatically linking gene and cell type information from millions of publications using existing indexed literature resources. Compared to manually constructed databases, CellMeSH is more comprehensive and scales automatically. The probabilistic query method enables reliable information retrieval even though the gene-cell type associations extracted from the literature are necessarily noisy. CellMeSH achieves up to 60% top-1 accuracy and 90% top-3 accuracy in annotating the cell types on a human dataset, and up to 58.8% top-1 accuracy and 88.2% top-3 accuracy on three mouse datasets, which is consistently better than existing approaches. Availability Web server: https://uncurl.cs.washington.edu/db_query and API: https://github.com/shunfumao/cellmesh
Building a New Testament Syllabus After the 2016 Elections

After the 2016 elections, students at Macalester College, a small private liberal arts college in Saint Paul, Minnesota, encouraged the faculty and staff to combat hate, sexism, racism, anti-Semitism, and white supremacy in and out of the classroom. These students inspired me to reconsider the way that I taught my introductory New Testament course. In this essay, I present the process by which I redesigned the course to explore not only the historical context of the New Testament texts but also our present political context and the ways it shapes biblical interpretation. The redesigned syllabus includes scholarship representative of the feminist, post-colonial, African American, Latinx, Asian-American, Jewish, queer, and other liberationist and identity-based approaches to the study of the New Testament.
TROPOMI NO2 in the United States: A Detailed Look at the Annual Averages, Weekly Cycles, Effects of Temperature, and Correlation With Surface NO2 Concentrations.

Observing the spatial heterogeneities of NO2 air pollution is an important first step in quantifying NOX emissions and exposures. This study investigates the capabilities of the Tropospheric Monitoring Instrument (TROPOMI) in observing the spatial and temporal patterns of NO2 pollution in the continental United States. The unprecedented sensitivity of the sensor can differentiate the fine-scale spatial heterogeneities in urban areas, such as emissions related to airport/shipping operations and high traffic, and the relatively small emission sources in rural areas, such as power plants and mining operations. We then examine NO2 columns by day-of-the-week and find that Saturday and Sunday concentrations are 16% and 24% lower respectively, than during weekdays. We also analyze the correlation of daily maximum 2-m temperatures and NO2 column amounts and find that NO2 is larger on the hottest days (>32°C) as compared to warm days (26°C-32°C), which is in contrast to a general decrease in NO2 with increasing temperature at moderate temperatures. Finally, we demonstrate that a linear regression fit of 2019 annual TROPOMI NO2 data to annual surface-level concentrations yields relatively strong correlation (R2 = 0.66). These new developments make TROPOMI NO2 satellite data advantageous for policymakers and public health officials, who request information at high spatial resolution and short timescales, in order to assess, devise, and evaluate regulations.
Analysis on DC Voltage Balance Control Between Three Phases for STATCOM

Maintaining the DC voltage balance between three phases is one of the keys to cascaded STATCOM. Due to the difference in parallel loss, switching loss, modulation ratio and pulse delay of the H-bridge unit, there is a problem of DC voltage imbalance between the three phases of cascaded STATCOM. To solve this problem, a simple zero-sequence voltage calculation method is proposed by deriving the output power relationship of cascaded STATCOM based on the existing zero-sequence voltage injection method. Meanwhile, considering the asymmetry of the power grid, the negative sequence component in the voltage will cause DC voltage unbalanced fluctuation of the phases, a power feedforward control method is proposed. The method calculates the unbalanced power generated by the negative sequence voltage in real time and feeds it forward, effectively suppressing the unbalanced power between the three phases during asymmetry. Simulation and experimental results verify the effectiveness of the proposed control method.
Super Odometry: IMU-centric LiDAR-Visual-Inertial Estimator for Challenging Environments.

We propose Super Odometry, a high-precision multi-modal sensor fusion framework, providing a simple but effective way to fuse multiple sensors such as LiDAR, camera, and IMU sensors and achieve robust state estimation in perceptually-degraded environments. Different from traditional sensor-fusion methods, Super Odometry employs an IMU-centric data processing pipeline, which combines the advantages of loosely coupled methods with tightly coupled methods and recovers motion in a coarse-to-fine manner. The proposed framework is composed of three parts: IMU odometry, visual-inertial odometry, and laser-inertial odometry. The visual-inertial odometry and laser-inertial odometry provide the pose prior to constrain the IMU bias and receive the motion prediction from IMU odometry. To ensure high performance in real-time, we apply a dynamic octree that only consumes 10 % of the running time compared with a static KD-tree. The proposed system was deployed on drones and ground robots, as part of Team Explorer's effort to the DARPA Subterranean Challenge where the team won $1^{st}$ and $2^{nd}$ place in the Tunnel and Urban Circuits, respectively.
Managerial Extrapolation: Who and When?

We show strong over-extrapolation of earnings in the I/B/E/S managerial guidance. Firms whose earnings are less persistent, less volatile, or more salient exhibit more extrapolation. Managers who observe rapid growth in their local housing market also demonstrate more extrapolation, albeit weaker. Over-extrapolation is not particularly related to a manager’s skills or tenure. Exploiting exogenous variations in firms’ profitability resulting from the 2017 Tax Cuts and Jobs Act, we provide clean evidence that managers over-extrapolate past earnings even when earnings experience a temporary shock. Consistent with Bordalo et al. (2020) and Afrouzi et al. (2021), our findings shed light on what factors affect the degree of over-extrapolation.
Identification of Breed Differences in Known and New Fescue Toxicosis Associated Phenotypes in Charolais-and Hereford-Sired Crossbred Beef Cows.

Beef cattle phenotypes are affected by the consumption of toxic fescue. Toxic fescue’s impact is dependent on heat stress and breed composition, with genetic variability for robustness to toxin exposure believed to exist within and across breeds. The study objective was to characterize the effect of fescue toxicosis across breeds for known and novel heat and fescue stress-associated phenotypes. One-hundred crossbred fall-calving Charolais- and Hereford-sired cows of parities 1–3 were allocated to graze either toxic fescue (n = 50), non-toxic fescue (n = 25), or a rotation between toxic and non-toxic fescue (n = 25) for 156 days. Phenotypes impacted by breed (genetics) included hair coat score (p < 0.0001), hair reduction/shedding rate (p < 0.05), rectal temperature (RT) (p < 0.0001), vaginal temperature (p < 0.05), serum phosphorus concentration (p < 0.02) and respiration rate (RR) (p < 0.003). Cows on toxic fescue experienced reduced hair shedding efficacy (p < 0.0001), higher vaginal temperatures (p < 0.0001), increased systolic blood pressure (p < 0.04), increased RR (p < 0.0001) and reduced average daily gain (p < 0.0001), compared to cows grazing non-toxic fescue. Calves born from cows with higher RT during the last third of gestation had higher RT at weaning (p < 0.02), indicating potential physiological effects of in utero heat stress. The study indicates that beef cows exhibit variable responses to toxic fescue within and across breeds which may impact future calf phenotypes.
Integrating reverse engineering into computer-aided software engineering (CASE)

A framework for the integration of reverse engineering of software systems into computer-aided software engineering (CASE) tools has been developed and applied to C source code. The process of coding a system conceals design information useful for system and code modification and upgrading as the system evolves during the operation and maintenance phase of its life cycle. Significant resources are being expended by the industry in maintaining existing code which was designed and implemented prior to CASE tools and for which little accurate documentation can be found. The framework developed here is intended to facilitate the recovery of design information in a manner which would allow the direct application of modern CASE tools to maintaining the software within the context of a Structured Design methodology. The design recovery framework emphasizes the identification of: module dependencies; visibility of information exchanged between modules, specifically, what data is exchanged and in which direction; visibility of information among modules through the global data area; and appropriate module assignments to subhierarchies in a structure chart. A software tool for reverse engineering of code to structure charts (RESC) is developed to demonstrate the framework. The RESC system employs heuristic rules to ensure repeatability, consistency, and correctness. The RESC system requirements are specified for several steps. The first is that of extracting information needed by the rules through parsing and lexically analyzing the code. The parser is generated from a grammar oriented towards a language's modular constructs and the usage of passed arguments in invocations, formal arguments within functions, and global variables by each function. Information extracted by the parsing program is used as input to a second program which applies the heuristic rules developed to produce a structure chart object database. A graphic layout procedure is specified for laying out the objects within a structure chart. A final program is specified to take the detailed files provided and create a structure chart description file which can be imported directly into a existing CASE tool which has graphic display, editing, and analyses capabilities. The application of this system to C-source code supports the feasibility of the approach.
Restricted Set of V Genes and Extensive Idiotype Crossreactivity of Autoantibodies

The production of antibodies recognizing self-antigens is one of the hallmarks of autoimmune diseases (1). Despite the obvious role of T cells in the production of autoantibodies and the existence of genetic and environmental factors, the investigation of autoreactive B cell clones may bring important clues in the comprehension of the pathogenesis of auto-immunity. One of the rational approaches is to look for the existence of common features among autoantibodies of various specificities. The existence of similarities could imply that common mechanisms are involved in diseases with different clinical manifestations.
Role of GABPα/β1 in the maintenance of gene expression at the TMS1 locus

AACR Annual Meeting-- Apr 14-18, 2007; Los Angeles, CA 4506 Many genes in the human genome are associated with CpG-dense DNA known as CpG “islands” at their 5’ ends. Aberrant methylation of CpG sites within such islands is associated with inappropriate gene silencing and has been implicated in the inactivation of tumor suppressor genes in human cancers. However, the mechanism responsible for eliciting these changes has yet to be elucidated. Our lab has identified a CpG island associated gene called TMS1 (Target of methylation-induced silencing-1) that is subject to epigenetic silencing in 40% of primary breast tumors and other cancers. The CpG island of TMS1 in normal somatic cells contains three DNaseI hypersensitive sites (HS) with two forming at the boundary between unmethylated and densely methylated flanking DNA. Aberrant methylation of TMS1 CpG island in cancer cells is accompanied by the loss of CpG island-specific DNaseI HS sites and gene silencing, indicating that local alterations in chromatin structure play an important role in methylation-dependent silencing. We identified a methylation-sensitive complex that bound to HS2 located in the first intron of TMS1. Using DNA affinity chromatography we identified one component of the complex as GABPα, a heterotetrameric ets family transcription factor. Interestingly, the interaction of GABP with its recognition sequence has been shown to be blocked by DNA methylation. It is our hypothesis that the GABP complex plays a role in maintaining the unmethylated, open chromatin structure across the CpG island domain of TMS1 in normal cells, either through direct effects on TMS1 transcription or by recruiting factors that mark the CpG island domain with a “permissive” histone code. To this end, we find that the GABP complex binds to a 55bp fragment of HS2 containing tandem ets transcription factor binding sites separated by 29bp. Methylation of a CpG in either ets site blocks GABP complex binding in vitro . Preliminary studies using chromatin immunoprecipitation show that the binding of GABP to the endogenous TMS1 locus is also sensitive to the methylation status of the locus in that HS2 is occupied by GABPα in cells that are unmethylated and express TMS1, but devoid of GABP binding in cells in which TMS1 is methylated and silent. We further examined the impact of HS2/GABP on TMS1 promoter activity through the use of luciferase assays. Inclusion of the HS2 element in the sense or anti-sense orientation resulted in a 2-3 fold increase in transcriptional activity from the TMS1 promoter in a normal fibroblast cell line and a transformed breast cancer cell line. Initial siRNA experiments indicate that transient knockdown of GABPα leads to a corresponding decrease in TMS1 expression. Taken together, these data support a role for the GABP complex and HS2 in the regulation of TMS1 expression. Spurious methylation of the GABP binding sites might be one mechanism contributing to the silencing of TMS1 in human cancer cells. Supported by NIH grants GM078787 and CA077337.
Overview and Foundations

The notes for this class offer an overview of the main application areas of statistics. The key ideas to appreciate are data, variation, and uncertainty.
Identification of a bottom quark-antiquark pair in a single jet with high transverse momentum and its application

In this paper, we introduce a new approach to identify a bottom quark-antiquark pair inside a single jet with high transverse momentum by using the jet substructure in the center-of-mass frame of the jet. We demonstrate that the method can be used to discriminate the boosted heavy particles decaying to a $b\overline{b}$ final state from QCD jets. Applications to searches for the standard model Higgs boson ($H$) decaying to $b\overline{b}$ when produced in association with a weak vector boson are also discussed.
Cultural conundrums: the ethics of epidemiology and the problems of population in implementing pre-exposure prophylaxis.

The impending implementation of pre-exposure prophylaxis (PrEP) has prompted complicated bioethical and public health ethics concerns regarding the moral distribution of antiretroviral medications (ARVs) to ostensibly healthy populations as a form of HIV prevention when millions of HIV-positive people still lack access to ARVs globally. This manuscript argues that these questions are in part concerns over the ethics of the knowledge production practices of epidemiology. Questions of distribution and their attendant cost-benefit calculations will rely on a number of presupposed and therefore normatively cultural assumptions within the science of epidemiology specifically regarding the ability of epidemiologic surveillance to produce accurate maps of HIV throughout national populations. Specifically ethical questions around PrEP will focus on who should receive ARVs given the fact that global demand will far exceed supply. Given that sexual transmission is one of the main modes of HIV transmission these questions of who are inextricably linked to knowledge about sexual personhood. As a result the ethics of epidemiology and how the epidemiology of HIV in particular conceives classifies and constructs sexual populations will become a critical point of reflection and contestation for bioethicists health activists physicians nurses and researchers in the multi-disciplinary field of global health. This paper examines how cultural conundrums within the fields of bioethics and public health ethics are directly implicated within the ethics of PrEP by analyzing the problems of population inaugurated by the construction of the men who have sex with men (MSM) epidemiologic category in the specific national context of South Africa. © 2013 John Wiley & Sons Ltd.
Superfluous, Mischievous or Emancipating? Thailand's Evolving Senate Today

In Thailand’s emerging democracy, the Senate has played an often underestimated role. This study analyzes Thailand’s Upper House, examining its historical evolution until 2009. In particular, it focuses on the following questions. What innovations did the 1997 Constitution bring to the Senate? How and why was the Senate adjusted under the 2007 constitution? The study further reviews the Senate elections of 2000 and 2006 as well as the election/selection of 2008. Finally, it postulates as to the continued significance of an Upper House in Thailand and offers recommendations for the future course of Thailand’s developing Senate.
The Solar Wind

The first evidence of the solar wind was provided through observations of comet tail deflections by L. Biermann in 1951. A cometary ion tail is oriented along the difference between the cometary and solar wind velocities, whereas the dust tail is in the antisunward direction; the ion tail directions demonstrated the existence of an outflow of ionized gas from the Sun (the solar wind) and allowed estimates of solar wind speed. Spacecraft observations have now established that at 1 AU the solar wind has a typical ion number density of about 7 /cc and is composed by number of about 95% protons and 5% Helium, with other minor ions also present. The solar wind as observed at 1 AU in the ecliptic has speeds typically in the range 300-700 km/ s. At such speeds ions travel from the Sun to 1 AU in from 2.5 to 6 days. The impact of the solar wind on planets with magnetic fields (Earth, Jupiter, Saturn, Uranus, Neptune) causes phenomena such as magnetospheres, aurorae, and geomagnetic storms, whereas at objects lacking magnetospheres (Mars, Venus, comets), atmospheric neutrals undergo charge exchange and are picked up by the solar wind flow. The solar wind also shields the Earth from low energy cosmic rays, and is responsible for the existence of the anomalous component of the cosmic rays a low energy component that is created locally rather than in the galaxy. Presented here is a brief introduction to the solar wind and a description of some current topics of research. Solar wind properties vary a great deal due to the changing magnetic structure on the Sun.
Electromagnetic extraction of energy from merging black holes

We calculate the evolution of the prompt intrinsic Poynting power generated by merging black holes. Orbiting black holes induce rotation of the space-time. In a presence of magnetic field supported by an accretion disk outside of the orbit, this results in a generation of an electromagnetic outflow via the Blandford-Znajek-type process with luminosity $L_{EM} \sim G^3 M^3 B^2/(c^5 R_{orb}) $ and reaching a fairly low maximum values of $L_{EM} = 10^{37}-10^{39} m_6 $ erg s$^{-1}$ ($m_6$ is the masses of black holes in millions of Solar mass) at the time of the merger. Dissipation of the wind power may produce two types of observed signatures: a highly variable collimated emission coming from the internal dissipation within the jets and a broad-band near-isotropic emission generated at the termination shocks.
A SYNOPTIC KEY AND EVALUATION OF SPECIES IN THE ASPERGILLUS FLAVUS GROUP

SUMMARY A synoptic key for identification of 16 taxa in the Aspergillus flavus group is presented. The key uses definitive and readily observable features: vesicle size, color of conidial heads, conidiophore and conidium features, growth at 37 C, and form and size of sclerotia. Brief descriptions are included as an aid to identification. The author's interpretation of relatedness among species, based upon morphological and cultural data and involving an ordination using coefficients of similarity, is compared to results from chemotaxonomic studies by other workers. A distributional and ecological analysis has been based upon examination of species lists in nearly 100 surveys. Aspergillus leporis, A. avenaceus, A. sojae, A. subolivaceus, and A. zonatus, in particular, are interpreted as morphologically and ecologically distinct species. Aspergillus flavus, A. oryzae, and A. parasiticus are in part domesticated species with broad and overlapping morphologies. Aspergillus toxicarius appears to be a biseriate form of A. parasiticus, and A. kambarensis probably belongs with A. oryzae. Additional isolates of Aspergillus leporis States & Christensen (65) from cool desert soils in Wyoming, southern Utah and northern Arizona, and isolation of a closely related taxon, also tightly columnar but with elongate, cream to russet sclerotia, stimulated a comparative study of species in the A. flavus group. The distinctive strain, 0 168, is a variant of A. leporis and is mentioned again in the brief description of that species. Aspergillus leporis is distinguished from A. flavus Link in the key and in the descriptions; it is not a synonym of A. flavus as has been suggested (59). The key was written with the intention of providing a practical guide to identification of species in the A. flavus group. Evaluations of synoptic keys and suggestions regarding their use can be found elsewhere (18, 39). The A. flavus group as described by Raper and Fennell (54) contained nine species. Since 1965, five species and four varieties have been newly described (6, 41, 48, 59, 65, 67), A. sojae Sakaguchi & Yamada, listed as a probable synonym of A. parasiticus Speare by Raper and Fennell, has been elevated to species status again (48), and A. corolligenus (Massee) Subram. and A. insecticola Subram., originally described in 1910 and 1879, respectively, have been transferred to Aspergillus, A. flavus group, from Sterigmatocystis Cramer (66). 1056
Proteomics as a tool for discovery: proteins implicated in Alzheimer's disease are highly expressed in normal pancreatic islets

A proteomic analysis of islets was undertaken to determine the protein constituents of normal adult mouse islets. Unexpectedly, we identified several islet proteins that are associated with the pathogenesis of Alzheimer's disease. Some of these proteins had chaperone activity that is integral to proper protein folding. This group includes GRP78, valosin-containing protein, calreticulin, protein disulfide isomerase, DnaK, HSP70, HSP60, and TCP-1. Additionally, neuronal proteins key to coordinated neuronal guidance and survival were also identified in islets. This group includes proprotein convertase subtilisin, collapsin response mediator protein 2, ubiquinol-cytochrome c reductase core protein, L-3-hydroxyacyl-Coenzyme A dehydrogenase, glutamine synthetase, peroxiredoxin, and secretogogin. An important subset of the proteins identified here has not been reported previously in pancreatic islets. Abnormal activity of these proteins in brain may contribute to the pathogenesis of Alzheimer's disease, a neurodegenerative condition characterized by focal amyloid deposits with neurofibrillary tangles. The putative role of these proteins in Alzheimer's pathogenesis is intriguing given the possible clinical relationship and pathological similarity of Alzheimer's disease to type 2 diabetes. These findings have therefore led to the hypothesis that these proteins may also play a role in type 2 diabetes.
Estimative influence measures for the multivariate general linear model

Abstract Within the context of the multiviriate general linear model, and using a Bayesian formulation and Kullback-Leibler divergences this paper provides a framework and the resultant methods for the problem of detecting and characterizing influential subsets of observations when the goal is to estimate parameters. It is further indicated how these influence measures inherently depend upon one's exact estimative intent. The relationship to previous work on observations influential in estimation is discussed. The estimative influence measures obtained here are also compared with predictive influence functions previously obtained. Several examples are presented illustrating the methodology.
Carbon utilization by the omnivorous flagellate Paraphysomonas imperforata

Carbon utilization by the omnivorous microflagellate Paraphysomonas imperforata was examined when this protozoan was fed either of two species of algae grown to three degrees of nitrogen limitation and three degrees of phosphorus limitation. Carbon incorporation (retention in the particulate fraction) by the microflagellate differed slightly for the two prey species but was a constant percentage of the total carbon budget of the protozoan for each prey alga (i.e. the degree of nitrogen or phosphorus deficiency of the algae did not affect carbon incorporation by the protozoan). The patterns of respiration in the six grazed cultures of each alga were also similar. Carbon incorporation and other nutrient utilization by this protozoan apparently were uncoupled to achieve this result. Firm conclusions are equivocal due to the possible dark uptake of nutrients by the algae. Our results are consistent, however, with a mathematical model in which the nutrient excretion rate is predicted from the respiration rate and gross growth efficiency of the protozoan and the C : N : P ratios of the protozoan and its prey.
Reactor applications of the compact fusion advanced rankine (CFAR) cycle for a D-T tokamak fusion reactor

The preliminary design of a high temperature blanket and compact power conversion system for a D-T reactor utilizing a mercury Rankine cycle and nonequilibrium MHD disk generators is described. The CFAR cycle is described in detail and a blanket geometry is proposed which is designed to give good heat transfer and low pressure drops for the two-phase boiling mercury flow in the presence of strong magnetic fields. The blanket utilizes beryllium and flibe in the low-temperature breeding zone and lithium aluminate in beryllium oxide pebbles in the high-temperature breeding zone to obtain a tritium breeding ratio of 1.07. With careful choice of materials and geometry, it has been possibly to have 46% of the neutron and gamma heat deposited in the high-temperature pebble beds at the back of the blanket. The design utilizes the many advantages of liquid-metal Rankine cycles, including low pressures, mass flow rates and pumping power, and superheating along with internal regeneration to achieve good thermal efficiencies of about 35% using the microwave superheater and about 32% without the microwave superheater. The capital costs are expected to be much lower than past design concepts because the MHD power generators and the mercury condensers and heat exchangers can all be placed inside the reactor vault; preliminary cost estimates indicate a very attractive cost of electricity for this advanced concept.
Virtual Reference Service in Academic Libraries in West Africa

As technology continues to advance, libraries in Europe and America continue to improve upon their virtual reference services by employing new Web technologies and applying them to existing services. West African academic libraries have begun providing resources electronically to their users but still typically lag behind in the services they offer. This research investigated virtual reference services offered by 79 academic libraries in ten West African countries. It was found that less than 40% provide any virtual reference service including phone, fax or email, and almost none take advantage of more advanced technologies such as chat or text messaging.
Cyanide-Bridged Heterobimetallic Complexes of the Group 6 Metal Carbonyls and Copper(I). X-ray Structures of (CO)5MCNCu(PPh3)3 (M = Cr, W) Derivatives

The cyanide-bridged compounds (CO)5MCNCu(PPh3)3 where M = W in 1, and M = Cr in 2 have been prepared by the reaction of NaM(CO)5CN with Cu(CH3CN)4BF4 and PPh3, and their solid-state structures have been determined crystallographically. In 1, the CN bond length was 1.15(2) A, and the bridge was slightly bent with angles of W−C(6)−N(1) = 175.9(14)° and Cu−N(1)−C(6) = 176(2)°. Crystal data for 1: monoclinic, space group P21/n, a = 20.376(4) A, b = 12.436(3) A, c = 22.423(5) A, β = 97.28(3)°, Z = 4, R = 7.90%. The chromium analog, complex 2, was isomorphous with 1. In addition, the isocyanide-bridged complex (CO)5WNCCu(PPh3)3 (3) was prepared by the reaction of CuCN with PPh3 and W(CO)5(THF) at −78 °C. The structure of this compound was determined by infrared and 13C NMR measurements. The isocyanide-bridged 3 was found to undergo thermal rearrangement to yield the cyanide-bridged 1. In the 13C NMR spectrum of 1 at room temperature, the CN peak is very broad (fwhh = 47 Hz) and can be found at 147.8 ppm. Dynam...
The synthesis and cycloadditions of C-Cyclopropyl nitrones

Abstract C-Cyclopropyl-N-methyl nitrone and C, C-dicyclopropyl-N-methyl nitrone have been synthesized, and the cycloadditions of these species to electron-deficient dipolarophiles have been studied.
Plate Tenting With a One-Sided Constraint

A concentrated load pushes the plate transversely away from a rigid surface. The problem is analyzed using energy minimization, and approximate, closed-form expressions are obtained for tent dimensions and interfacial loads
A variational multiphase model for simultaneous MR image segmentation and bias correction

In this paper, we present a multiphase segmentation model for MR images in the presence of strong intensity inhomogeneity. The problem is formalized as a constraint min-max optimization problem that consists both primal and dual variables. We use the primal dual hybrid gradient (PDHG) algorithm to alternately solve for the optimal solutions. The proposed algorithm is quite efficient in that all the subproblems have closed form solutions. Moreover, the computational complexity is shown to be linear with respect to the size of the image. Numerical experiments on various images demonstrated that our algorithm outperforms recently developed methods in terms of efficiency and accuracy.
Geodetic accuracy of the Macrometer model V-1000

The Macrometer Model V-1000 is a geodetic positioning instrument that uses the radio signals broadcast by the GPS satellites. The Macrometer is the only GPS user equipment commercially available that does not require any of the GPS codes. The Model V-1000 receives only the 19-cm wavelength signals from GPS although similar instruments, built for the U.S. Air Force Geophysics Laboratory, receive both the 19-and the 24-cm wavelengths. In this paper we summarize the results of two years of field testing of the V-1000. This instrument, observing four or five satellites fof a few hours, yields a point position accurate within several meters in each coordinate: latitude, longitude and ellipsoidal height. All three components of the relative position vector between a pair of points can be determined within 2 parts per million of the distance, given a similar schedule of observations. This accuracy has been obtained for intersite distances from one kilometer to several thousand kilometers.
Recognising ocean acidification in deep time: An evaluation of the evidence for acidification across the Triassic-Jurassic boundary

Abstract While demonstrating ocean acidification in the modern is relatively straightforward (measure increase in atmospheric CO 2 and corresponding ocean chemistry change), identifying palaeo-ocean acidification is problematic. The crux of this problem is that the rock record is a constructive archive while ocean acidification is essentially a destructive (and/or inhibitory) phenomenon. This is exacerbated in deep time without the benefit of a deep ocean record. Here, we discuss the feasibility of, and potential criteria for, identifying an acidification event in deep time. Furthermore, we investigate the evidence for ocean acidification during the Triassic-Jurassic (T-J) boundary interval, an excellent test case because 1) it occurs in deep time, beyond the reach of deep sea drilling coverage; 2) a potential trigger for acidification is known; and 3) it is associated with one of the ‘Big Five’ mass extinctions which disproportionately affected modern-style invertebrates. Three main criteria suggest that acidification may have occurred across the T-J transition. 1) The eruption of the Central Atlantic Magmatic Province (CAMP) and the associated massive and rapid release of CO 2 coincident with the end-Triassic mass extinction provide a suitable trigger for an acidification event (full carbonate undersaturation in the surface ocean is possible but improbable). 2) Tentative evidence for a global paucity of carbonate across the end-Triassic mass extinction versus the adjacent stratigraphy is consistent with a predicted sedimentary response to acidification. 3) The end-Triassic mass extinction was particularly selective against acid-sensitive organisms (more so than perhaps any other extinction event) and temporarily eliminated coral reefs. Therefore multiple lines of evidence are consistent with a T-J ocean acidification event within our current resolution to recognise such events in deep time. The conclusion that the end-Triassic extinction was influenced by acidification implies that short-term acidification perturbations may have long-term effects on ecosystems, a repercussion that has previously not been established. Although anthropogenic emissions are more rapid than any event in the geologic record, events such as the T-J can serve as partial analogues for the present anthropogenic carbon release. Since the T-J was such a pronounced crisis for both modern-style marine invertebrates and scleractinian reefs, it is of particular interest in terms of informing projections about the effects of modern ocean acidification.
Phenotypic and genetic polymorphisms among human herpesvirus-6 isolates from North American infants

Fifteen human herpesvirus-6 (HHV-6) isolates from North American infants with primary infection manifest as febrile or roseola (exanthem subitum) like illnesses were characterized phenotypically on the basis of their in vitro growth in continuous T-cell lines and primary human mononuclear cells and by their reactivity with monoclonal antibodies. All isolates replicated efficiently in primary human cord blood mononuclear cells, but five distinct patterns of viral replication in human cells lines were observed. Two of the HHV-6 isolates from infants were found to replicate in HSB-2 cells, a property associated with so-called group A viruses, which had previously been isolated only from adults. These same isolates also reacted with a panel of A-specific monoclonal antibodies. Genomic characterization of viral isolates using well-characterized restriction site polymorphisms indicated that these two isolates contained a mixture of both A- and B-type genomes, in different proportions. These data suggest that not all HHV-6 isolates can be categorized into one of two broad groups and that such segregation of HHV-6 isolates may in fact be misleading.
Synthesis and characterization of the monomeric aluminum monoamides (tert-Bu) 2AlN(R)R' (R and R' = bulky aryl, alkyl, or silyl groups)

The synthesis and characterization of the compounds (r-Bu) 2 AlNR 2 (R=Mes, 1, and SiPh 3 , 2) and (r-Bu) 2 AlN-(R')SiPh 3 (R'=2,6-i-Pr 2 CoH 3 (Dipp), 3, and 1-adamantyl (1-Ad), 4) are described. They were characterized by X-ray crystallography and 1 H NMR and IR spectroscopy. In the crystal phase, the structures of 1-4 are monomeric with essentially trigonal planar coordinations at aluminum and nitrogen and Al-N bond lengths that range from 1.82 to 1.89 A.
Portamento and the Phonograph Effect

In the early 1930s portamento, a technique that had long been integral to the art of violin playing, began to fall into disfavor. This article contends that the decline in portamento was closely tied to the rise of a technology that was intended to preserve—not change—musical performance: sound recording. The decline of portamento may be understood in part as a “phonograph effect,” a response to the unique qualities and demands of recording technology. While portamento may create a sense of impulsiveness or spontaneity in concert, robust sliding (which was common in the early twentieth century) may sound calculated or contrived when heard repeatedly on record. Moreover, violinists found that early microphones tended to exaggerate portamento to an unacceptable degree. Thus, what had been one of the primary expressive vehicles in violin playing became a subtle and selectively applied ornament, in strong measure in response to a technology that could transform sound and make performances permanent.
Examining Seasonally Pulsed Detrital Transport in the Coastal Everglades Using a Sediment Tracing Technique

The Comprehensive Everglades Restoration includes plans to restore freshwater delivery to Taylor Slough, a shallow drainage basin in the Southern Everglades, ultimately resulting in increased freshwater flow to the downstream Taylor River estuary. The effect of altered hydrologic regime on the transport dynamics of flocculent, estuarine detritus is not well understood. We utilized a paramagnetic sediment tracer to examine detrital transport in three Taylor River pond/creek pairs during early wet versus late wet transition season estuarine flow conditions. Flux of floc tracer was greatest in the downstream direction during all observations, and was most pronounced during the early wet season, coincident with shallower water depth and faster discharge from northern Taylor River. Floc tracer was more likely to move upriver during the late wet/dry season. We observed a floc tracer transport velocity of approximately 1.74 to 1.78 m/day across both seasonal hydrologic conditions. Tracer dynamics were also surprisingly site-dependent, which may highlight the importance of channel geomorphology in regulating hydrologic and sediment transport conditions. Our data suggest that restoration of surface water delivery to Taylor River will influence downstream loading of detritus material into riverine ponds. These detrital inputs have the potential to enhance ecosystem primary productivity and/or secondary productivity.
Gender and sexuality in animated television sitcom interaction

The active ‘doing’ of gender and sexuality in and through social interaction has been a topic of academic inquiry for several decades. This study examines the cultural reproduction of that ‘doing’ through the onscreen discourse of the animated television sitcom. A conversation-analytic approach to various excerpts from two popular series reveals the ways in which the situated interactions of these programs make gender and sexuality overtly relevant to viewers through polarization of ‘the norm’ versus deviations from it at the level of talk. In temporarily deviating from their everyday, normative speech practices, characters tap into viewers’ preconceived notions of the behaviors of different gendered and sexual identities in interaction. These non-normative actions are then oriented to as such in the onscreen discourse, thereby making gender, sexuality, and the conduct associated with those identities simultaneously salient for the at-home viewer. It is hypothesized that, while these gender-/sexuality-bas...
Permeability of silicone polymers to ammonia and hydrogen sulfide

Mesure des coefficients de permeabilite de NH 3 et H 2 S dans 11 membranes de silicones (polydialkylsiloxane, polydimethylsilmethylene, polysilphenylenesiloxane) de 10 a 55 o C et jusqu'a 8 atm. Influence importante de la nature de la chaine, de l'encombrement des substituants sur le coefficient. Comparaison avec d'autres gaz penetrants (CO 2 , H 2 , He, C 2 H 4 , N 2 , etc...) et discussion des facteurs provoquant les differences
North American approach to the design of continuous Z- and C- purlins for gravity loading with experimental verification

Abstract The design of cold-formed, through fastened, roof purlins requires a significant number of assumptions. The usual North American practice is to make the following major assumptions: constrained bending, full continuity through the lapped section, and a lap strength equal to the sum of individual purlin strengths. To verify these assumptions, test results of multiple span purlin systems were gathered from 10 laboratories. Of the 45 test results reported, 24 were found to be sufficiently documented for complete evaluation. Comparison of the test results and analysis/design procedures using the above assumptions and AISI specification provisions showed that the assumptions are valid.
Diffusion of gases across the shell of the hen's egg.

Abstract Chicken egg shells, with the inner shell membrane removed, have been studied to determine their diffusive permeability to oxygen. This was done by measuring the oxygen flux through a section of the shell across which there was initially a difference in oxygen partial pressure but not in total gas pressure. The measured oxygen permeabilities, corrected to 37 °C, averaged 3.2 × 10 −6 cm 3 STP · sec −1 · cm −2 · mm Hg −1 , and did not appear to change with incubation age. From this value the permeabilities for carbon dioxide and water vapor were calculated to be 2.5 × 10 −6 and 4.0 × 10 −6 cm 3 STP · sec −1 · cm −2 · mm Hg −1 , respectively. Also from the oxygen permeability data we were able to estimate a total pore area of 2.3 mm 2 and an average pore diameter of 17 micra. The latter figure agrees well with direct observations. Finally, calculations were made which show that the inner and outer shell membranes, if dry, are a negligible barrier to gas diffusion compared to the shell. This means that the egg shell, the porosity of which is set when the egg is laid, is of prime importance in determining oxygen uptake and carbon dioxide and water vapor loss by the developing embryo.
Personal power and positional power in a power-full `I': a discourse analysis of doctoral dissertation supervision:

This article explicates the specific manners in which professorial power is indexed and implemented in the first personal pronoun `I' in academic discourse. The matter of analytic interest is to find out how the semiotic sign `I' acquires its semantic property of power in the pragmatic context of doctoral supervision. The data under consideration consist of two dyadic interactions conducted respectively by a PhD candidate with her two supervisors in an American university. The data analyses reveal that professorial power may be performed in two different ways (personal and positional) in three types of communicative acts — directive, evaluative, and explanative. The findings here may have some important implications for academic supervision in terms of the relationship between language and power.
Cationic conductances of nutrient and secretory membranes of frog stomach in Cl--free solutions.

SummaryThe K+ conductance in Cl- -free media of the frog gastric mucosa of Rana pipiens was found to be relatively high and essentially the same for both the nutrient and secretory membranes. The replacement of Na+ with either Mg2+ or Ca2+ in either the nutrient or secretory solution and in the presence of 4 mM K+ in both solutions increased the resistance and decreased the PD. An analysis of the results for the nutrient membrane suggests that Mg2+ and Ca2+ block the K+ pathway.
Creep of Polymer Matrix Composites. II: Monkman-Grant Failure Relationship for Transverse Isotropy

This research concerns polymer matrix composite (PMC) materials having long or continuous reinforcement fibers embedded in a polymer matrix. The objective is to develop comparatively simple, designer friendly constitutive equations intended to serve as the basis of a structural design methodology for this class of PMC. Here (Part II), the focus is on extending the damage/failure model of an anisotropic deformation/damage theory presented earlier. A companion paper (Part I) by the writers deals with creep deformation of the same class of PMC. The extension of the damage model leads to a generalization of the well known Monkman/Grant relationship to transverse isotropy. The usefulness of this relationship is that it permits estimates of (long term) creep rupture life on (short term) estimates of creep deformation rate. The current extension also allows estimates of failure time for various fiber orientations. Supporting exploratory experiments are defined and conducted on thin-walled specimens fabricated from a model PMC. A primary assumption in the damage model is that the stress dependence of damage evolution is on the transverse tensile and longitudinal shear traction acting at the fiber/matrix interface. We conjecture that a supplemental mechanism of failure is the extensional strain in the fiber itself. The two postulated mechanisms used in conjunction suggest that an optimal fiber angle may exist in this class of PMC, maximizing the time to creep failure.
Ameliorating mammograms by using novel image processing algorithms

Mammography is one of the most important tools for the early detection of breast cancer typically through detection of characteristic masses and/or micro calcifications. Digital mammography has become commonplace in recent years. High quality mammogram images are large in size, providing high-resolution data. Estimates of the false negative rate for cancers in mammography are approximately 10%–30%. This may be due to observation error, but more frequently it is because the cancer is hidden by other dense tissue in the breast and even after retrospective review of the mammogram, cannot be seen. In this study, we report on the results of novel image processing algorithms that will enhance the images providing decision support to reading physicians. Techniques such as Butterworth high pass filtering and Gabor filters will be applied to enhance images; followed by segmentation of the region of interest (ROI). Subsequently, the textural features will be extracted from the ROI, which will be used to classify the ROIs as either masses or non-masses. Among the statistical methods most used for the characterization of textures, the co-occurrence matrix makes it possible to determine the frequency of appearance of two pixels separated by a distance, at an angle from the horizontal. This matrix contains a very large amount of information that is complex. Therefore, it is not used directly but through measurements known as indices of texture such as average, variance, energy, contrast, correlation, normalized correlation and entropy.