cssi/SciSciGPT-SciSciNet huggingface dataset:
Three-dimensional printing facilitates surgical planning for resection of an atypical cardiac myxoma.

Background Cardiac myxomas are common and account for 50% of primary intracardiac tumors. Atypical locations of cardiac myxoma increase the risk of intraoperative iatrogenic injuries. Herein, we report a case of using three-dimensional printing (3D) to facilitate the removal of an atypical cardiac myxoma in a 63-year-old woman. Methods and results Mass in the high posterior atrial septum was confirmed through imaging. Due to the potential involvement of the mass to surrounding vital structures, 3D printing of the cardiac mass was performed. The tumor was completely resected via median sternotomy and the resulting defect was repaired with the bovine pericardium. The patient had an uncomplicated postoperative course except for the development of sick sinus syndrome. One-year follow-up showed no tumor recurrent. Conclusion 3D printing technology in patients with atypical cardiac tumors enhances our understanding of the extent of the tumor invasion and facilitates planning the operation to avoid intraoperative complications.
Sexual health education for adolescents and young adults with intellectual and developmental disabilities: recommendations for accessible sexual and reproductive health information

Sexual and reproductive health is an important aspect of human development, but discussions with adolescents and young adults on this topic are often challenging for health-care providers. As a result, many adolescents and young adults do not receive appropriate, comprehensive sexual education, despite recognition from WHO and the UN that access to this education is a human right. Adolescents and young adults with mild to moderate intellectual or developmental disability, or both, are just as likely to be sexually active as are their peers without disability; however, these individuals are less likely to receive comprehensive sexual education. To ensure adequate comprehensive sexual education for adolescents and young adults with intellectual and developmental disabilities, sexual health educators should facilitate conversations about sexual and reproductive health that are non-judgmental and sexually inclusive. Such initiatives should use an educational framework grounded in universal design for learning, including use of multiple media types with clear, concise language and images.
Redshift limits of BL Lacertae objects from optical spectroscopy

Context. BL Lacertae objects have been the targets for numerous recent multiwavelength campaigns, continuum spectral variability studies, and theoretical spectral and variability modeling. A meaningful interpretation of the results of such studies requires a reliable knowledge of the objects' redshifts; however, the redshifts for many are still unknown or uncertain. Aims. Therefore, we hope to determine or constrain the redshifts of six BL Lac objects with unknown or poorly known redshifts. Methods. Observations were made of these objects with the MDM 2.4 m Hiltner telescope. Although no spectral features were detected, and thus no redshifts could be measured, lower redshift limits were assigned to the objects based on the expected equivalent widths of absorption features in their host galaxies. Redshifts were also estimated for some objects by assuming the host galaxies are standard candles and using host galaxy apparent magnitudes taken from the literature. Results. The commonly used redshift of z = 0.102 for 1219+285 is almost certainly wrong, while the redshifts of the other objects studied remain undetermined.
Ten-Year experience with vertical rectus abdominis myocutaneous flap for reconstruction of abdominoperineal resection defects.

Abstract Purpose We evaluate outcomes of our single center using vertical rectus abdominis myocutaneous (VRAM) flaps for reconstruction after abdominoperineal resection (APR). Our goal was to analyze factors that may affect perineal wound healing, a problematic complication with APR reconstructions due to location and high frequency of neoadjuvant chemoradiation. Methods This single-center, retrospective study analyzed all VRAM flap perineal reconstruction patients after APR defect over a 10-year period (from July 2008 to June 2018). Outcome measures focused on factors that may affect perineal wound healing complication rates: cancer stage (I/II vs III/IV), neoadjuvant chemoradiation, surgeon's years in practice ( 5 years), and pelvic closed suction drain use. Results Twenty-eight patients met inclusion criteria. The overall major perineal wound complication rate was 14.3% (4 patients). Lack of perioperative closed suction pelvic drain use was associated with a significantly higher rate of major perineal wound complications (28.6% vs 0% and p = 0.031). All four major wound complications occurred in patients who did not have a pelvic drain. The major perineal wound complication rate for patients who underwent neoadjuvant chemoradiation was 22% vs 0% with no neoadjuvant chemoradiation (p = 0.107). Conclusion While our cohort represents a relatively small single-center study, our 14.3% rate of major perineal wound complications is consistent with previous studies in the literature. Our findings show that perioperative pelvic closed suction drain use is associated with a lower rate of perineal wound complications. While neoadjuvant chemoradiation trended toward a higher incidence of perineal wound complications, it did not reach statistical significance.
Inter-study and time-dependent variability of metabolite abundance in cultured red blood cells

Cultured human red blood cells (RBCs) provide a powerful ex vivo assay platform to study blood-stage malaria infection and propagation. In recent years, high-resolution metabolomic methods have quantified hundreds of metabolites from parasite-infected RBC cultures under a variety of perturbations. In this context, the corresponding control samples of the uninfected culture systems can also be used to examine the effects of these perturbations on RBC metabolism itself and their dependence on blood donors (inter-study variations). Time-course datasets from five independent studies were generated and analysed, maintaining uninfected RBCs (uRBC) at 2% haematocrit for 48 h under conditions originally designed for parasite cultures. Using identical experimental protocols, quadruplicate samples were collected at six time points, and global metabolomics were employed on the pellet fraction of the uRBC cultures. In total, ~ 500 metabolites were examined across each dataset to quantify inter-study variability in RBC metabolism, and metabolic network modelling augmented the analyses to characterize the metabolic state and fluxes of the RBCs. To minimize inter-study variations unrelated to RBC metabolism, an internal standard metabolite (phosphatidylethanolamine C18:0/20:4) was identified with minimal variation in abundance over time and across all the samples of each dataset to normalize the data. Although the bulk of the normalized data showed a high degree of inter-study consistency, changes and variations in metabolite levels from individual donors were noted. Thus, a total of 24 metabolites were associated with significant variation in the 48-h culture time window, with the largest variations involving metabolites in glycolysis and synthesis of glutathione. Metabolic network analysis was used to identify the production of superoxide radicals in cultured RBCs as countered by the activity of glutathione oxidoreductase and synthesis of reducing equivalents via the pentose phosphate pathway. Peptide degradation occurred at a rate that is comparable with central carbon fluxes, consistent with active degradation of methaemoglobin, processes also commonly associated with storage lesions in RBCs. The bulk of the data showed high inter-study consistency. The collected data, quantification of an expected abundance variation of RBC metabolites, and characterization of a subset of highly variable metabolites in the RBCs will help in identifying non-specific changes in metabolic abundances that may obscure accurate metabolomic profiling of Plasmodium falciparum and other blood-borne pathogens.
Detection of Pythium spp. in golf course irrigation systems.

Many Pythium spp. are causal agents of diseases of turfgrasses. Pythium spp. disseminate through irrigation systems in agricultural settings, and this study provides evidence that Pythium spp. also disseminate through golf course irrigation. Water samples were collected from irrigation heads and water sources at ten golf courses in Missouri and Kansas. Samples were collected from 2018 to 2019 in April, July, and October. Phosphorus, nitrogen, and chloride concentrations were measured from irrigation head samples to determine if these parameters influence frequency of Pythium spp. detected. Pythium spp. were detected in samples through baiting and membrane filtration. Cultures were isolated on PARP media and DNA was extracted from putative Pythium isolates. The ITS region was PCR amplified and sequenced. Phylogenetic trees were constructed using representative sample sequences, sequences from seven morphologically identified reference isolates of Pythium, and similar Genbank accessions. Detected Oomycete species include Lagenidium giganteum, Pythium biforme, P. insidiosum, P. marsipium, P. plurisporium, and Saprolegnia hypogyna. Twenty-one clades lacked species-level resolution, and fourteen of these clades were associated with Pythium species. Clades A, C, D, E, I, and M contain Pythium species that cause root and crown rot on creeping bentgrass. Detected Pythium communities were dependent on the detection method used and sampling source. Pythium frequency and diversity were highest in April 2019. Sample temperature, sampling site, chloride, and nutrient concentrations did not influence Pythium frequency in samples. Irrigation systems using surface water sources contained at least three Pythium spp. over the course of two years.
Benefit or burden? Perceptions of energy efficiency efforts among low-income housing residents in New York City

Low-income households contend with high energy costs and poor thermal comfort due to poor structural conditions and energy inefficiencies in their homes. Energy efficiency upgrades can potentially reduce energy expenses and improve thermal comfort, while also addressing problematic issues in the home environment. The present mixed method pilot study explored the impacts of energy efficiency upgrades in 20 households in a low-income community in New York City. Surveys and interviews were administered to the heads of household in a variety of housing types. Interviews were also conducted with landlords of buildings that had recently undergone upgrades. Findings indicate that energy efficiency measures resulted in improved thermal comfort, enhanced health and safety and reduced energy costs. Participants reported largely positive experiences with the upgrades, resulting in direct and indirect benefits. However, results also indicate negative consequences associated with the upgrades and further illustrate that weatherization alone was insufficient to address all of the issues facing low-income households. Moreover, qualitative results revealed differing experiences of low-income renters compared to homeowners. Overall, energy efficiency upgrades are a promising intervention to mitigate the energy and structurally related challenges facing low-income households, but larger scale research is needed to capture the long-term implications of these upgrades.
Review of Alice Dreger’s Galileo’s Middle Finger: Heretics, Activists, and the Search for Justice in Science

Assaults on free speech and academic inquiry are increasingly familiar in the present age of social media. Even as I started Alice Dreger’s compelling new book, Galileo’s Middle Finger: Heretics, Activists, and the Search for Justice in Science, Dreger’s colleague at Northwestern, author and film professor Laura Kipnis, was the target of a Title IX investigation for publishing an opinion piece in the Chronicle of Higher Education (Kipnis 2015a). Kipnis had criticized new codes regulating sexual relations on campus for infantilizing students “while vastly increasing the power of university administrators over all our lives” (Kipnis 2015b). Students at Northwestern clamored to be protected from these harmful ideas, simultaneously proving Kipnis’s point about the deterioration of campus discourse, and initiating the surreal and pointless investigation. Although the charges against Kipnis were eventually dropped, the incident highlighted growing demands from students to be shielded from any form of emotional discomfort, including exposure to ideas with which they might disagree. Such exposure is now routinely portrayed as equivalent to physical injury, a metaphorical conflation of words with violence that manifests itself in a variety of forms, including the popular concepts of microaggression and triggering. This invidious comparison is designed for one purpose alone—to justify the suppression of speech by some higher authority. What happens, though, when it is not political speech that is deemed offensive and threatening, but an empirical claim about the natural world? Jonathan Rauch, in his book Kindly Inquisitors, warned that liberal science is perpetually under threat from a “humanitarian” stance that judges ideas not by their truth, but by their potential for harm. A minor example of this caught my eye recently when a study was published estimating that 64% of women who do scientific fieldwork are subject to sexual Hum Nat DOI 10.1007/s12110-015-9235-6
Selection of New Human Foreskin Fibroblast Cell Strains for Interferon Production

The aim of this work has been to isolate and characterize new diploid cell strains, suitable for large-scale production of human fibroblast interferon. Twenty cell strains were isolated from individual neonatal foreskins obtained with the informed consent of the donors’ parents. The techniques employed for the isolation of the cell strains were aimed at obtaining the highest possible yield of normal diploid cells, free of contaminating microorganism and viruses. The bulk of the cell yield has been frozen at a low population doubling level. Each of the isolated cultures was tested for interferon producing characteristics with poly(I)·poly(C) under a number of different conditions including “superinduction” with metabolic inhibitors. Most of the newly established cell strains produced lower interferon yields than the reference FS-4 cell strain. However, some new cell strains produced similar interferon yields as the FS-4 cells on superinduction. Five cell strains, designated FS-30, FS-35, FS-44, FS-48 and FS-49, identified as the highest interferon producers among the new cells, were selected for further testing. Of these, three cell strains (FS-35, FS-48 and FS-49) produced similar interferon yields as FS-4 cells after superinduction. Cell strains FS-48 and FS-49 were found to have stable interferon producing characteristics over a wide span of population doubling levels. The interferon produced in these new cell strains had the antigenic and biological characteristics of human fibroblast interferon.
Dynamic Random-Element Stereograms: A Microprocessor Application

Dynamic random-element stereogram stimuli may be used to elicity psycho-physical and/or electrophysiological responses whose presumptive neurogenic basis lies in the cerebral cortex. Such stimuli can be generated at low cost using a ‘home’ graphics microcomputer, plus a special interface and a TV to provide the binocular display. In effect, any graphics picture made by the microcomputer in black, white, and gray is translated by the interface into crossed disparity (‘near’), uncrossed disparity (‘far’), or no disparity (‘fixation distance’) correlates of 3-D depth. An observer actually views a screen full of dynamically changing, randomly occuring elements onto which the selected disparities have been introduced.
A Model of Job Facet Satisfaction

Abstract This study was undertaken to identify facets, or elements, of the job that lead to overall job satisfaction. Public employees completed an employee attitude survey; men and women were equally represented in this sample. Closed-ended items rated on a five-point Likert scale covered commonly accepted facets of job satisfaction such as pay and supervision. Open-ended questions were also included in the attempt to locate as yet unidentified facets. The model developed in this study included 17 facets: promotion, training, supervisor, upper management, organization of work tasks, work stress, work challenge and autonomy, physical work space and equipment, work group, organizational commitment, organizational structure, pay, merit pay, affirmative action, benefits, job security, and distribution of staff. Although the number of facets is large, each is recommended for inclusion in future models to test the level of overall job satisfaction explained by this model.
A bridge too far: cold and pathogen constraints to assisted migration of riparian forests

Assisted migration of warm-adapted genotypes to currently cooler climates may reduce maladaptation from future climate change. Few assisted migration trials have considered limitations of the cooler climates and pathogens currently present at transplant sites. This is especially important to consider in riparian ecosystems that are priority targets for restoration in the western United States as they harbor diverse communities. In an effort to validate assisted migration as an effective strategy for mediating the negative impacts of climate change, we used a provenance trial with replicated genotypes from 19 populations of the foundation riparian tree species, Fremont cottonwood (Populus fremontii), transplanted to a cold site to test for genetic variation in growth, mortality, and resistance to shoot blight fungi (Venturia sp.). Populations from cool sites had up to 4 times faster growth, 3 times higher survival, and 8 times higher resistance to Venturia than populations from warm sites, providing evidence of local adaptation to both climate and pathogenic fungi. Budburst phenology and shoot blight were correlated with frost damage, subsequent shrub-form architecture, and mortality. While climate change models predict 6°C increases, plants transferred distances of 6°C at this time would not perform well; an intermediate transfer distance of less than 3°C would avoid maladaptation to the current environment during assisted migration. Thus, multiple and intermediate transfer phases to supplement local genetic variation will likely be necessary for effective assisted migration to accommodate current environments and large changes in climate.
Further evaluation of [11C]MP‐10 as a radiotracer for phosphodiesterase 10A: PET imaging study in rhesus monkeys and brain tissue metabolite analysis

[11C]MP-10 is a potent and specific PET tracer previously shown to be suitable for imaging the phosphodiesterase 10A (PDE10A) in baboons with reversible kinetics and high specific binding. However, another report indicated that [11C]MP-10 displayed seemingly irreversible kinetics in rhesus monkeys, potentially due to the presence of a radiolabeled metabolite capable of penetrating the blood-brain-barrier (BBB) into the brain. This study was designed to address the discrepancies between the species by re-evaluating [11C]MP-10 in vivo in rhesus monkey with baseline scans to assess tissue uptake kinetics and self-blocking scans with unlabeled MP-10 to determine binding specificity. Ex vivo studies with one rhesus monkey and 4 Sprague-Dawley rats were also performed to investigate the presence of radiolabeled metabolites in the brain. Our results indicated that [11C]MP-10 displayed reversible uptake kinetics in rhesus monkeys, albeit slower than in baboons. Administration of unlabeled MP-10 reduced the binding of [11C]MP-10 in a dose-dependent manner in all brain regions including the cerebellum. Consequently, the cerebellum appeared not to be a suitable reference tissue in rhesus monkeys. Regional volume of distribution (VT) was mostly reliably derived with the multilinear analysis (MA1) method. In ex vivo studies in the monkey and rats only negligible amount of radiometabolites was seen in the brain of either species. In summary, results from the present study strongly support the suitability of [11C]MP-10 as a radiotracer for PET imaging and quantification of PDE10A in nonhuman primates. Synapse 69:86–95, 2015. © 2014 Wiley Periodicals, Inc.
Core Particles of Hepatitis B Virus and Ground Squirrel Hepatitis Virus I. Relationship Between Hepatitis B Core Antigen- and Ground Squirrel Hepatitis Core Antigen-Associated Polypeptides by Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis and Tryptic Peptide Mapping

The relationships among the core antigen polypeptides of hepatitis B virus (HBV) and ground squirrel hepatitis virus (GSHV) were studied using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and tryptic peptide mapping. The major core antigen polypeptides of liver-derived HBV (p22) and GSHV (p20.5) shared 56% of the spots in their peptide maps. Comparison of hepatitis B core antigen (HBcAg) p19 or ground squirrel hepatitis core antigen (GSHcAg) p16.5 with their respective major polypeptides indicated that these components probably resulted from cleavage of the major polypeptide of each virus. Other polypeptides smaller than the major component of each virus were often faint on polyacrylamide gels and probably resulted from the cleavage or degradation of components larger than p22 of HBcAg or p20.5 of GSHcAg, since their peptide maps contained spots unique to these high-molecular-weight components. p26 of GSHcAg and p27.5 of HBcAg shared approximately two-thirds of the spots on their peptide maps with those of their respective major core polypeptides. Furthermore, p37.5 of GSHcAg and p40 of HBcAg shared about 60% homology with their respective major polypeptides, and also shared many of the spots that were unique to p26 of GSHcAg or p27.5 of HBcAg but were not found in the peptide map of their respective core antigen polypeptides. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis bands larger than 40,000 daltons were variably present, and peptide mapping indicated that these were aggregates of various smaller core antigen-associated polypeptides. The results suggest that p40 of HBcAg and p37.5 of GSHcAg are the largest unique polypeptides in these core particles, and that they are encoded for by the genome of each virus. That a subset of the spots unique to p40 or p37.5 was also found in p27.5 of HBcAg or p26 of GSHcAg, respectively, as compared to the major core polypeptides, also suggests that p27.5 and p26 are unique proteins encoded by the genome of each virus. It is proposed that the core antigen gene of each virus is larger than that which would encode the major polypeptide of each virus, and that the genetic organizations of the core genes of HBV and GSHV are very similar.
Steps toward Unifying Dual Language Programs, Common Core State Standards, and Critical Pedagogy: Oportunidades, Estrategias y Retos

Recent education reforms have begun to reframe academic discussion and teacher practice surrounding bilingual educational approaches for preparing “21st century, college and career ready” citizens. Given this broader context, in this article we examine ways that we might join implementation of dual language programs, Common Core State Standards, and critical pedagogy at the school and classroom levels via a teacher, school administrator, and teacher professional development program. We focus on a concrete example of a partnership between a progressive dual language school along the U.S.-Mexico border, known as Chula Vista Learning Community Charter School, and a bilingual teacher education program in the College of Education at San Diego State University, which prepares teachers and administrators to implement and develop dual language instruction aligned (but not beholden) to Common Core State Standards. We include discussion of a Freirian-based instructional program that helps unite the opportunities presented by dual language programs and standardsbased reform initiatives in a deeper equity and social justice framework for educating students. We discuss opportunities (oportunidades), strategies (estrategias), and challenges (retos) encountered during this collaborative work between the bilingual teacher preparation program, a Dual Language school, and one exemplary fourth grade teacher team and their enactment of a critical pedagogy-based curriculum. We conclude with a discussion of implications of our work for education of multilingual learners and the educators that work with them.
Sampled-Data Modeling and Control Design for Nonlinear Pulse-Width Modulated Systems

Techniques for sampled-data modeling and control design of nonlinear pulse-width modulated systems are introduced. The modeling results are based on formal exponential series with Lie derivative operators. The control design is based on a multirate strategy, useful for deadbeat tracking or feedback linearization.
Ion-exchange procedures : X. Cation exchange in concentrated HClO4-HCl solutions

The cation-exchange behavior of a number of elements in concentrated HClO4-HCl mixtures has been studied with a Dowex 50 resin. Adsorption data as a function of acid composition and application of the data to column separations are given. Activity coefficients of HCl and HClO4 in the resin phase have been determined for two- and three-component aqueous systems. Some implications of the results for determination of complex constants of species in the aqueous phase are discussed.
Optical measurement of membrane potential.

Optical measurement of membrane potential is a new tool for physiologists and has already found many applications. However, the number of possible pitfalls is alarming, particularly in situations where comparison with electrode measurements is impossible. Exhaustive and elaborate controls are clearly necessary; and yet they never provide complete assurance that an optical signal represents a change in membrane potential. In our opinion, the use of redistribution signals, which are slower, and thus more likely to represent to secondary effects of changes in membrane potential, and require permeant dyes with access to the internal millieu, may be more hazardous than the use of either fast or intrinsic signals. However, the larger size of the redistribution signals has endowed them with obvious appeal. If more sensitive fast signals can be found, the use of this kind of signal would be facilitated.
Factoryless Goods Producing Firms

Abstract This paper documents the existence and characteristics of US firms that do not manufacture themselves, but nonetheless are heavily involved in the production of goods. These factoryless goods producing firms (FGPFs) are formally in the wholesale sector but, unlike traditional wholesale firms, FGPFs design the goods they sell and coordinate production activities. FGPFs in the wholesale sector are larger and younger, pay higher wages, span more sectors and had more manufacturing employment in previous years compared to traditional wholesalers. FGPFs are more likely to import than typical wholesalers, though their imports constitute a smaller share of their total domestic activity.
Organolanthanide-Catalyzed Intramolecular Hydroamination/Cyclization of Amines Tethered to 1,2-Disubstituted Alkenes

[reaction: see text] This contribution reports the organolanthanide-catalyzed intramolecular hydroamination/cyclization of amines tethered to 1,2-disubstituted alkenes to afford the corresponding mono- and disubstituted pyrrolidines and piperidines by using coordinatively unsaturated complexes of the type (eta(5)-Me(5)C(5))(2)LnCH(TMS)(2) (Ln = La, Sm), [Me(2)Si(eta(5)-Me(4)C(5))(2)]NdCH(TMS)(2), [Et(2)Si(eta(5)-Me(4)C(5))(eta(5)-C(5)H(4))]NdCH(TMS)(2), and [Me(2)Si(eta(5)-Me(4)C(5))((t)()BuN)]LnE(TMS)(2) (Ln = Sm, Y, Yb, Lu; E = N, CH) as precatalysts. [Me(2)Si(eta(5)-Me(4)C(5))((t)BuN)]LnE(TMS)(2) mediates intramolecular hydroamination/cyclization of sterically demanding amino-olefins to afford disubstituted pyrrolidines in high diastereoselectivity (trans/cis = 16/1) and in good to excellent yield.
Clusters of the hydronium ion (H3O+) with H2, N2 and CO molecules

Abstract The thermochemistry of H 3 O + (X) n clusters (X = H 2 , N 2 and CO and n = 1–3) was determined by equilibrium measurements using the mass selected drift tube technique. The binding energies for H 3 O + (H 2 ) n ( n = 1 and 2) are 3.4 and 3.5 kcal mol −1 , and for H 3 O + (N 2 ) n ( n = 1–3) are 7.8, 7.3 and 6.3 kcal/mol, respectively. The binding energy of the polar CO molecule is 11.2 kcal mol −1 , and ab initio calculations show that the H 2 OH + ⋯CO conformation is more stable than the H 2 OH + ⋯OC conformation. Saddle point energy of 17.6 kcal/mol is calculated for inversion between these conformational isomers.
A one-day double-labelling technique for tissue specimens: Immunogold-silver staining forin situ hybridization combined with alkaline phosphatase-anti-alkaline phosphatase (APAAP) immunohistochemistry for antigens

An improved technique is described that addresses the problems of sensitivity, specificity, the use of hazardous radioactive equipment and time consumption in immunohistochemical labelling and double labelling ofin situ hybridization of tissue specimens. It consists of a two-step protocol in which digoxigenin-uridine triphosphate (UTP) labelled riboprobes in thein situ hybridization step are visualized by the immunogold-silver staining method, and double labelling of tissue antigens is achieved by the application of an alkaline phosphatase-anti-alkaline phosphatase staining step. We tested this protocol using snap-frozen tissue sections of synovial tissue from patients with rheumatoid arthritis. The target mRNA was detected by perforin or cathepsin D riboprobes, the double labelling was performed using anti-collagen type IV and alpha-smooth muscle actin antibodies. It is concluded that, in comparison with an established three-to four-day double-labelling protocol used in many laboratories, this one-day combination is currently the most rapid assay of reliable quality for double labelling ofin situ hybridization products and tissue antigens.
Thin-Film Hydrodynamics in Fluid Interface-Atomic Force Microscopy

Repulsive and attractive hydrodynamic interactions are measured between an oil droplet (n-hexadecane) and various glass microspheres in aqueous environments with an atomic force microscope (AFM). The magnitude and form of the hydrodynamics in a spherically wrapping thin film are investigated with a parametric study on external approach velocity and probe radius. The actual sphere−drop separation at closest approach can be experimentally deconvoluted in some situations from parametric data without ambiguity. Theoretical force profiles are calculated from the augmented Young−Laplace equation modified to allow for two distinct hydrodynamic drainage regimes: Reynolds lubrication for thick films with slightly deformed drops and a wrapping film condition for the indented interface. Also, an increase in film stability is directly observed as a function of velocity between a hydrophobized glass sphere and oil in pure water and in the presence of sodium dodecyl sulfate (SDS) below the critical micelle concentrati...
Shape of large single- and multiple-shell fullerenes

The morphology of multiple-shell fullerenes is investigated by ab initio calculations using Yang's O(N) method. It is found that for large single-shell fullerenes with ${\mathit{I}}_{\mathit{h}}$ symmetry, the spherical morphology has lower energy than that of polyhedrons. The formation energy per atom follows a simple scaling law. Including an estimate of intershell van de Waals interactions leads to the conclusion that spherical multiple-shell fullerenes are likely the most stable structure of large carbon clusters. These results are in good agreement with recent experiments.
Structural and functional effects of hereditary hemolytic anemia-associated point mutations in the alpha spectrin tetramer site.

The most common hereditary elliptocytosis (HE) and hereditary pyropoikilocytosis (HPP) mutations are α-spectrin missense mutations in the dimer-tetramer self-association site. In this study, we systematically compared structural and functional properties of the 14 known HE/HPP mutations located in the α-spectrin tetramer binding site. All mutant α-spectrin recombinant peptides were well folded, stable structures, with only the R34W mutant exhibiting a slight structural destabilization. In contrast, binding affinities measured by isothermal titration calorimetry were greatly variable, ranging from no detectable binding observed for I24S, R28C, R28H, R28S, and R45S to approximately wild-type binding for R34W and K48R. Binding affinities for the other 7 mutants were reduced by approximately 10- to 100-fold relative to wild-type binding. Some sites, such as R28, were hot spots that were very sensitive to even relatively conservative substitutions, whereas other sites were only moderately perturbed by nonconservative substitutions. The R34W and K48R mutations were particularly intriguing mutations that apparently either destabilize tetramers through mechanisms not probed by the univalent tetramer binding assay or represent polymorphisms rather than the pathogenic mutations responsible for observed clinical symptoms. All α0 HE/HPP mutations studied here appear to exert their destabilizing effects through molecular recognition rather than structural mechanisms.
A New Monomeric Saturated N-Heterocyclic Silylene as a Racemic Mixture

A new stable silylene, rac-N,N‘-di-tert-butylethylene-4,5-dimethyl-1,3-diaza-2-silacyclopentan-2-ylide, has been made by reaction of the corresponding dibromide with KC8. Unlike the analogous silylene lacking the two methyl groups, which tetramerizes in concentrated solution or as a solid, the new silylene shows no tendency to oligomerize; instead, it persists as a stable colorless liquid.
A stability criterion for tunnel diodes

Given the complete linear equivalent circuit of a tunnel diode, a new sufficient condition is presented for the diode to be "potentially stable," where the diode is "potentially stable" if all open circuit natural frequencies can be shifted to the left half of the complex frequency plane, by properly imbedding the tunnel diode in a two terminal passive network.
Women and development: A highland New Guinea example

This paper presents an analysis of household variables and their relationship to success in cash cropping among the Gainj of Madang Province, Papua New Guinea. Censuses and household surveys from 1978, the year in which cash cropping began, and 1983 provide data that show different patterns of change in household structure for more and less commercially successful households. The results illustrate the importance of women's labor in economic development and the dynamic nature of the relationship between household structure and economic development.
Electrostatically accelerated coupled binding and folding of intrinsically disordered proteins

Intrinsically disordered proteins (IDPs) are now recognized to be prevalent in biology, and many potential functional benefits have been discussed. However, the frequent requirement of peptide folding in specific interactions of IDPs could impose a kinetic bottleneck, which could be overcome only by efficient folding upon encounter. Intriguingly, existing kinetic data suggest that specific binding of IDPs is generally no slower than that of globular proteins. Here, we exploited the cell cycle regulator p27(Kip1) (p27) as a model system to understand how IDPs might achieve efficient folding upon encounter for facile recognition. Combining experiments and coarse-grained modeling, we demonstrate that long-range electrostatic interactions between enriched charges on p27 and near its binding site on cyclin A not only enhance the encounter rate (i.e., electrostatic steering) but also promote folding-competent topologies in the encounter complexes, allowing rapid subsequent formation of short-range native interactions en route to the specific complex. In contrast, nonspecific hydrophobic interactions, while hardly affecting the encounter rate, can significantly reduce the efficiency of folding upon encounter and lead to slower binding kinetics. Further analysis of charge distributions in a set of known IDP complexes reveals that, although IDP binding sites tend to be more hydrophobic compared to the rest of the target surface, their vicinities are frequently enriched with charges to complement those on IDPs. This observation suggests that electrostatically accelerated encounter and induced folding might represent a prevalent mechanism for promoting facile IDP recognition.
Recollection rejection: Gist cuing of verbatim memory

Recollection rejection allows people to avoid accepting related lures presented on recognition tests by recollecting their instantiating study items. Two predictions made by fuzzy trace theorists were tested. First, recollection rejection should likely occur when verbatim traces are available for retrieval. Second, related lures that closely approximate the gist of their instantiating study items should be more likely to evoke recollection rejection than related lures that do not provide such a match. In support of the first condition, estimates of recollection rejection were lower when participants studied items under divided as opposed to full attention. In support of the second prediction, estimates of recollection rejection were greater when participants were presented with antonyms as related lures, as opposed to rhymes. The present results contribute to the cued recall and recognition literatures by demonstrating that recollection rejection is moderated by similar factors as is cued recall.
HCO radical kinetics: Conjunction of laser photolysis and intracavity dye laser spectroscopy

HCO radical at a concentration of about 1014 cm−3 is produced by monochromatic laser photolysis of H2CO with a 0.6 mJ frequency-doubled, flashlamp-pumped dye laser pulse. Intracavity dye laser spectroscopy quantitatively monitors HCO absorbance near 614 nm as a function of delay time between photolysis and probing pulses. Rate constants for HCO + O2 and HCO + NO are found to be 4.0 ± 0.8 × 10−12 and 1.45 ± 0.2 × 10−11 cm3 molecule−1 sec−1.
Crystalloids of Phycomyces sporangiophores: nature and photosensitive accumulation

Crystalloids accumulate in the vacuoles of the giant sporangiophores of Phycomyces blakesleeanus Burgeff during growth. On the basis of solubility in alkaline solutions, cytochemical staining reactions, trypsin sensitivity, optical absorption and response in the Lowry protein test, the crystalloids have been judged to consist principally of an acidic protein. In assays by Lowry test and by reference to optical absorption at 280 mmu, dark-grown sporangiophores were consistently found to contain from 2 to 4 times as much crystalloid material as light-grown counterparts. Concurrent assays of soluble phenolic materials revealed no significant effect of culture illumination, while carotene content of sporangiophores and mycelium was found to be raised from 2 to 4-fold by illumination during growth.
Fixed-ratio performance following ventromedial hypothalamic lesions in rats

Rats with ventromedial hypothalamic lesions were trained preoperatively to respond for food reward on a FR 64 schedule of reinforcement. Postoperative comparisons with similarly trained unoperated control rats showed no differences when both groups were maintained at 80% or 90% of their preoperative baseline weights. Lesioned rats responded at a much higher level, however, at 100% body weight and at a prefeeding condition run at 100% body weight. These results suggest that rats sustaining such lesions overeat and become obese because these lesions increase their hunger motivation.
1563 CEREBRAL AUTOREGULTION IN NEONATAL PUPPIES

In an attempt to document autoregulation of cerebral blood flow in the hyperoxic and hypoxic newborn animal, cerebral blood flow was measured in 6 hyperoxic (HE) and 4 hypoxic (H) neonatal puppies aged 2-13 days using the radioactive microsphere reference organ technique. In the HE group arterial oxygen tension was maintained above 250 torr with 100% O2 throughout all periods. In the H group arterial oxygen tension was maintained at 47.5 torr ± 7.6 SEM by continuous administration of 12% O2. Following control measurements (period I), puppies were made hypotensive (period II) by withdrawing 15-25 ml/kg of blood in the HE group and 20-32 ml/kg in the H group. In the HE group during period II, mean blood pressure fell 20.5% ± 2.8 (p=0.016) and cardiac output decreased 20.9% ± 5.7 (p = 0.016) while cerebral blood flow was unchanged (31.37 ± 3.76 and 32.69 ± 5.90 ml/100g/min in periods I and II respectively). When hypoxic animals were made hypotensive, mean blood pressure fell 18.6% ± 4.7 and cardiac output decreased by 47.9% ± 10.9 while cerebral blood flow was unchanged (38.66 ± 4.64 and 45.2 ± 4.00 ml/100g/min in period I and II respectively). The fraction of cardiac output to the cerebrum increased from 2.8% ± 0.4 to 3.8% ± 0.8 in the HE animals (p < 0.05) and from 2.5% ± 0.5 to 6.3% ± 1.1 in the H group (p < 0.05) during hypotension. Thus, in the presence of decreased mean blood pressure and cardiac output in both hyperoxic and hypoxic neonatal puppies, cerebral blood flow is maintained, demonstrating the presence of cerebral autoregulation.
Retaining Black Students in Engineering: Do Minority Programs Have a Longitudinal Impact?

In an effort to assist minority populations who are at risk of attrition in science, mathematics, and engineering programs, university administrators have launched and evaluated minority support programs. One such program implementation and evaluation was completed and reported, which noted trends in academic outcomes of program participants, such as grade point averages and standardized mathematics and science reasoning test scores, with participants' outcomes observably exceeding those of a similar sample of nonprogram participants (Good, Halpin, & Halpin, 1999). As is true with many program evaluations, however, this data only revealed information concerning achievement of the students in the freshman year and did not follow the students' success into subsequent years after program completion. Therefore, the purpose of this study was to examine if an effect on academic achievement occurred throughout the participants' sophomore years of study and if participants in the program were more likely to remai...
Integrated simulation combining process-driven and event-driven models

A simulation framework that integrates process-driven and event-driven approaches offers a powerful combination of tools to the modeller. In process-driven simulation models, the system can be represented by block diagrams or system networks through which entities flow to mimic real-life system objects. In event-driven models, the system can be represented by event graphs, which focus on the abstraction of the event rather than on observable physical entities. In this research, a simulation environment is proposed that integrates both the approaches, that is, process and event. One of the main outcomes of working in such an environment is that modellers can manage the complexity of large models based on real-world systems through process orientation, while retaining the control over the attributes, variables and the logic through event orientation. Discrete event simulation is often taught to students at either the event level or the process level. A simulation tool that effectively preserves both levels would be helpful in more effectively educating future simulation modellers.
Versatile multimodal system for surface profile measurements using a wrist-mounted laser device

In this paper we describe development and integration of a point laser sensor for precise proximity measurements and surface characterization in a robotic workcell. The proximity measurement and surface characterization system utilizes a commercially available point laser device. The device is small in size and its light weight allows for easy mounting on the end- effector of an industrial robotic arm. The system has three operational modes: point measurement, line profile measurement, and surface image measurement. All of the necessary calibration techniques, computer and robot controller interfaces, and data acquisition and processing algorithms have been developed and extensively tested. These tests have indicated that the system is able to provide submillimeter measurement accuracy and is very efficient. Point measurements can be made instantaneously, and the line and grid measurements can be performed in seconds to minutes, depending upon the desired resolution. These features along with the low cost, and three operational mode versatility makes this system quite unique and of practical utility. The system has proven very valuable in proximity research in active exploration of robotic workcells.
The Education and Labor Market Outcomes of Adolescent Fathers

The author examines the educational and labor market outcomes of young men in the United States, with a particular emphasis on adolescent fathers. She finds that men who were teen fathers complete fewer years of education and are less likely to finish high school compared to men who were not teen fathers. These educational deficits persist even after family and personal characteristics are taken into account. Teen fathers enter the labor market earlier and initially earn more money than do other men; by the time teen fathers reach their mid-20s, however, they earn less. After controlling for personal traits and family background, the long-term earnings deficits of teen fathers disappear, implying that teen fathers are as capable of providing for their children as are other young men from similarly disadvantaged backgrounds. Unfortunately, this will not ease the jobs of child support enforcement officials, who must regularly confront young, low-income, absent fathers and/or improve the plight of welfare-de...
Hydrogen/deuterium exchange and mass spectrometric analysis of a protein containing multiple disulfide bonds: Solution structure of recombinant macrophage colony stimulating factor‐beta (rhM‐CSFβ)

Studies with the homodimeric recombinant human macrophage colony-stimulating factor beta (rhM-CSFβ), show for the first time that a large number (9) of disulfide linkages can be reduced after amide hydrogen/deuterium (H/D) exchange, and the protein digested and analyzed successfully for the isotopic composition by electrospray mass spectrometry. Analysis of amide H/D after exchange-in shows that in solution the conserved four-helix bundle of (rhM-CSFβ) has fast and moderately fast exchangeable sections of amide hydrogens in the αA helix, and mostly slow exchanging sections of amide hydrogens in the αB, αC, and αD helices. Most of the amide hydrogens in the loop between the β1 and β4 sheets exhibited fast or moderately fast exchange, whereas in the amino acid 63–67 loop, located at the interface of the two subunits, the exchange was slow. Solvent accessibility as measured by H/D exchange showed a better correlation with the average depth of amide residues calculated from reported X-ray crystallographic data for rhM-CSFα than with the average B-factor. The rates of H/D exchange in rhM-CSFβ appear to correlate well with the exposed surface calculated for each amino acid residue in the crystal structure except for the αD helix. Fast hydrogen isotope exchange throughout the segment amino acids 150–221 present in rhM-CSFβ, but not rhM-CSFα, provides evidence that the carboxy-terminal region is unstructured. It is, therefore, proposed that the anomalous behavior of the αD helix is due to interaction of the carboxy-terminal tail with this helical segment.
Thermal vacancies and the yield anomaly of FeAl

Abstract We review here the George-Baker model for the yield strength anomaly of FeAl which is based on hardening by thermal vacancies at intermediate temperatures and dislocation creep at high temperatures. Results of up-quenching and down-quenching experiments, which corroborate the vacancy hardening mechanism, are discussed. Some implications of the model are compared with available experimental results.