cssi/SciSciGPT-SciSciNet huggingface dataset:
Surgical repair of a cesarean scar defect using a vaginal approach.

Objective To discuss the signs and symptoms of a cesarean section (C-section) scar defect, and to describe the techniques to repair the defect using a vaginal approach. Design A video review of a 32-year-old woman with abnormal bleeding and a C-section scar defect managed surgically by vaginal repair. The patient provided consent for video recording and publication. This surgical report, with no identifying patient data, was exempt from the institutional review board approval. Setting Tertiary care facility. Patient(s) A 32-year-old gravida 2, para 2 woman was seen with prolonged menses, and an 11 × 9 × 5-mm C-section scar defect was seen on transvaginal ultrasound. Intervention(s) The patient opted for the repair of the C-section scar defect using a vaginal approach. Main Outcome Measure(s) Postoperative course. Result(s) The patient had resolution of her prolonged menses, and transvaginal ultrasound showed improvement of her C-section scar defect. Conclusion(s) The vaginal approach is an efficacious way to repair a C-section scar defect, particularly when the defect occurs low at the level of the cervix.
Dynamic Data-Driven Simulation: Connecting Real-Time Data with Simulation

Data plays an essential role in almost every aspect of computer modeling and simulation. Oren’s differentiation of the types of simulations and discussions of how data can impact simulations provide a conceptual framework to categorize the many existing works of using data in simulation. Existing works in the extant literature were developed from the perspective of modeling, e.g., using data to support model design, model calibration, and model validation. In this chapter, we focus on using data from the perspective of simulation, i.e., assimilating real-time sensor data into a running simulation model in the context of online simulation.
Comptroller v. Wynne and the Futile Search for Non-Discriminatory State Taxation

In Comptroller v. Wynne, the U.S. Supreme Court has been asked to determine whether Maryland’s unapportioned income tax on resident taxpayers violates the Dormant Commerce Clause because it does not offer a fully offsetting credit for income taxes that its residents pay to other jurisdictions. The Court is reviewing a decision by the Maryland Court of Appeals, which found the state's partial-credit system to be unconstitutional. Unfortunately, the Maryland court's analysis adopted a non-discrimination standard that requires locational neutrality, a result that is not possible under the current structure of our federal system. Pure locational neutrality cannot be obtained unless the Court or Congress were to significantly intrude upon states' historic taxing powers. This Essay provides a brief review of the Maryland court's analysis, discusses the concept of locational neutrality, and cautions the Court against adopting locational neutrality as its non-discrimination standard. The Essay concludes by addressing two potential avenues that the Court could take to avoid adopting a problematic standard.
Trust on the Internet: A Virtual Reality?

Social capital has recently gained popularity, but it is not a new topic. The relationship between civic engagement and trust has been well tested, and it has been used in the past to help diagnose the well being of a society. Unfortunately with evolving technology, some of this research may be now obsolete. The Internet has changed the way that people comlnunicate and learn. Since the Internet has reached such high proliferation rates, especially among the younger generations, it is likely to have an effect on the relationship between civic engagement and trust. Using NES survey data from 1996 to 2004 primarily, I tested the effects of the Internet on said relationship, and Internet access had an effect on social trust.
Accuracy of ultrasonic fetal weight prediction in preterm infants.

Abstract We analyzed the accuracy of four previously reported ultrasound formulas by means of abdominal circumference and/or biparietal diameter measurement for the prediction of fetal weight in the preterm infant (
Investment Decisions and Offspring Gender

Economic research has documented many economic affects of offspring gender on parental behavior. However, an open question exists as to whether offspring gender has any influence on parental investment decision making. Specifically, I investigate whether female offspring have an impact on investment decisions with respect to stock and bondholding. Using a panel data set, I find that for male respondents, having only female offspring increases the probability of stockholding by over 17%. In contrast, a relationship between stockholding and offspring gender was not at all present for female respondents.
Quantum field theory over F1

In this paper we discuss some questions about geometry over the field with one element, motivated by the properties of algebraic varieties that arise in perturbative quantum field theory. We follow the approach to F_1-geometry based on torified-schemes. We first discuss some simple necessary conditions in terms of the Euler characteristic and classes in the Grothendieck ring, then we give a blowup formula for torified varieties and we show that the wonderful compactifications of the graph configuration spaces, that arise in the computation of Feynman integrals in position space, admit an F_1-structure. By a similar argument we show that the moduli spaces of curves M_(0,n) admit an F_1-structure, thus answering a question of Manin. We also discuss conditions on hyperplane arrangements, a possible notion of embedded F_1-structure and its relation to Chern classes, and questions on Chern classes of varieties with regular torifications.
Effect of multiyear drought on upland sediment yield and subsequent impacts on flood control reservoir storage

[1] Since the early 1950s, the U.S. Soil Conservation Service (SCS) and later the U.S. Department of Agriculture Natural Resources Conservation Service has built over 11,000 flood control reservoirs (FCR) in 47 states. FCR built in Texas and Oklahoma in the early 1950s to mid-1950s were impounded during the most severe drought on record in the region. In this study, the sediment trapped in FCR is used to reconstruct the variation in sediment yield through the drought years to the present. New sediment surveys of four FCR in McCulloch County, Texas, are combined with three previous surveys by the SCS. The new surveys are conducted using acoustic profiling to map water depth and sediment thickness in submerged areas of the reservoirs and real-time kinematic GPS in the dry areas. Sediment coring is used to determine sediment dry bulk density. The survey results are used to construct a composite history of the normalized sediment yield for the study area. Normalized sediment yield is the annual sediment yield normalized by the soil erodability factor K and the combined slope length and steepness factor LS of the watershed. The results indicate that sediment yield was lowest during the relatively drought-free period from 1971 to 2007, averaging 4.2 t/ha/yr/unit K/unit LS and over 70 times higher during the early part of the 1950s drought from 1951 to 1953, averaging 300.3 t/ha/yr/unit K/unit LS. These results have important implications for predicting the remaining useful life of FCR in the region and planning for future droughts.
Compiler support for value-based indirect branch prediction

Indirect branch targets are hard to predict as there may be multiple targets corresponding to a single indirect branch instruction. Value Based BTB Indexing (VBBI), a recently proposed indirect branch prediction technique, utilizes the compiler to identify a ‘hint instruction', whose output value strongly correlates with the target address of an indirect branch. At run time, multiple targets are stored at different branch target buffer (BTB) locations indexed using the branch PC and the hint instruction output value. In this paper, we present compiler support for the VBBI prediction scheme. We also propose compiler and run time optimizations to increase the dynamic instruction count between the indirect branch and its corresponding hint instruction. The more the dynamic instructions between the hint-jump instruction pair, the more likely that the hint value will be available when making the prediction. Our evaluation shows that the proposed compiler and run time optimizations improve the VBBI prediction accuracy from 66% to 80%. This translates into performance improvement from 17.2% (baseline VBBI) to 24.8% (optimized VBBI) over the traditional BTB design and from 11% (baseline VBBI) to 17.3% (optimized VBBI) over the best previously proposed indirect branch prediction scheme.
Recovery of normal testicular ultrastructure and sperm motility after cessation of gossypol treatment in rats.

This study evaluates the reversibility of the effects of gossypol on testicular ultrastructure and the motility of epididymal spermatozoa. Adult male rats were treated 6 days weekly with the vehicle alone (Group A), or with 10 (Group B) or 20 (Group C) mg/kg of gossypol for 12 weeks, and then sacrificed six or 12 weeks after cessation of treatment. Although epididymal spermatozoa in Groups B and C were 100% immotile after gossypol treatment, little evidence of abnormality could be detected with the light microscope in the seminiferous tubules or interstitium. By contrast, at the ultrastructural level, there were demonstrable pathognomonic defects in the mitochondrial sheath and axonemes of step 18 and 19 spermatids which were identical to those reported earlier (Hoffer, 1983). In addition, an ultrastructural defect in the flagella of late testicular spermatozoa is described for the first time. This defect consists of an indentation, or constriction, of the mitochondrial sheath at outer dense fibers (ODFs) 1, 2, and 9, resulting in a separation of these 3 ODFs from the other fibers. This defect, though visible in an earlier ultrastructural study (Hoffer, 1983), was not described. In Group B rats allowed to recover from gossypol treatment, ultrastructural defects in step 18 and 19 spermatids could not be detected at six or at 12 weeks after cessation of treatment, and sperm motility also did not differ significantly from controls by the end of either recovery period. In Group C rats, sperm motility returned to the normal range within six weeks after treatment ended, but a few morphological defects in the midpiece and axoneme of late spermatids could still be detected with the electron microscope. However, after 12 weeks of recovery, ultrastructural evidence of drug treatment could no longer be seen. The results of this study do not support the concern that use of gossypol leads to subtle irreversible damage in the testis which has previously escaped detection. These findings provide the first reported ultrastructural evidence that recovery from gossypol treatment is time and dose-related, and that there is a complete reversal of its deleterious effects. The observations on the motility of epididymal spermatozoa at the end of the treatment and recovery periods support these conclusions.
Influence of Task and Situational Variables on the Applicability of Vigilance Data to Physical Security

Vigilance is one of the most thoroughly researched areas of human performance. Volumes have been written concerning vigilance performance in both laboratory and real-world settings, and there is a clear trend in the literature toward an increasing emphasis on the study of operational task behavior under environmental conditions that are common to real world jobs. Although a great deal of this research has been designed to test various aspects of the many theories of vigilance, there is a general belief that vigilance research is relevant and applicable to the performances required in real-world monitoring and inspection tasks. Indeed, many of the reported studies are justified on the basis of their apparent relevance to vigilance requirements in modern man-machine systems, industrial inspection tasks, and military jobs. There is a growing body of literature, however, which suggests that many vigilance studies are of limited applicability to operational task performance. For example, Kibler (1965) has argued that technological changes have altered job performance requirements to the extent that laboratory vigilance studies are no longer applicable to real-world jobs. Many others have simply been unable to reproduce the typical "vigilance decrement" in field situations. This has led Teichner (1974) to conclude that "the decremental function itself is more presumed than established." Language: en
Projected Hartree Product Wavefunctions

A method for performing a restricted configuration interaction calculation on atoms or molecules based on the use of Young operators from the symmetric groups is discussed and its relation to some other types of calculations is pointed out. The method in its most general form can be said to be an extension of the independent particle approach which represents the wavefunction in terms of the n best possible one‐particle orbitals for the n‐particle system. Illustrations are given for the hydrogen molecule, the helium atom, and the allyl radical.
Velocity saturation current-mode CMOS imaging sensor

A current-mode CMOS imaging sensor is presented in this paper. The read-out transistor in the photo pixel operates in velocity saturation regime and allows for high linearity between integrated photo charges and output drain current. The column parallel read-out circuitry implements a novel current conveyor with a feedback mechanism which improves matching of the output currents across the imaging array. Correlated double sampling (CDS) is performed on-chip in order to improve noise characteristics of the imager. A prototype of the proposed imaging sensor was fabricated in 0.18μm triple well CMOS process. The sensor operation and measurements are presented.
Perinatal leukemia with apossible variant of the Ellis-van Creveld syndrome

Summary A case of perinatal leukemia with a possible variant of the Ellis-van Creveld syndrome is presented. A newborn boy with scaphocephaly, sagittal craniosynostosis, recurved pinna, hypoplastic upper lip, natal teeth, short ribs and extremities, absent breast areolae, bilateral cryptorchism, and a normal karyotype died of acute myeloblastic leukemia at 34 days of age. This association is previously unreported.
Differential ammonia metabolism in Aedes aegypti fat body and midgut tissues.

Abstract In order to understand at the tissue level how Aedes aegypti copes with toxic ammonia concentrations that result from the rapid metabolism of blood meal proteins, we investigated the incorporation of 15N from 15NH4Cl into amino acids using an in vitro tissue culture system. Fat body or midgut tissues from female mosquitoes were incubated in an Aedes saline solution supplemented with glucose and 15NH4Cl for 10–40 min. The media were then mixed with deuterium-labeled amino acids, dried and derivatized. The 15N-labeled and unlabeled amino acids in each sample were quantified by mass spectrometry techniques. The results demonstrate that both tissues efficiently incorporate ammonia into amino acids, however, the specific metabolic pathways are distinct. In the fat body, the 15N from 15NH4Cl is first incorporated into the amide side chain of Gln and then into the amino group of Gln, Glu, Ala and Pro. This process mainly occurs via the glutamine synthetase (GS) and glutamate synthase (GltS) pathway. In contrast, 15N in midgut is first incorporated into the amino group of Glu and Ala, and then into the amide side chain of Gln. Interestingly, our data show that the GS/GltS pathway is not functional in the midgut. Instead, midgut cells detoxify ammonia by glutamate dehydrogenase, alanine aminotransferase and GS. These data provide new insights into ammonia metabolism in A. aegypti mosquitoes.
Holographic Laser-Protective Eyewear

Holographic filters in spectacle lenses, helmet visors and other types of substrates have been proposed for eye protection against visible lasers. Dyes and filter glasses, commonly used as laser protection at visible wavelengths, typically suffer from poor visual transmittance. Holographic filters offer potentially high visual transmittance due to a narrow spectral notch, but the angular dependence of the spectral notch position dictates a tradeoff between eye protection and visual transmittance. The relative merits of various exposure and substrate configurations for laser-protective eyewear are compared. Emphasis is placed on single-beam exposure, surface-conformal fringe structures in which the local Bragg angle is determined by the fringe spacing as opposed to the fringe tilt. This type of hologram is readily made free from flare or multiple images in transmission. Performance is evaluated in terms of visual transmittance versus eye protection, including retinal area and eye rotation. The relationship between angular and spectral response of holographic laser filters determines the exposure source for optimum performance to be roughly coincident with the center of eye rotation, regardless of the substrate geometry. Performance may be improved by locating the filters a greater distance from the eye. A more dramatic improvement in performance may be achieved by increasing the curvature of the substrate so that it is concentric with the eye.
Reversal learning as a measure of impulsive and compulsive behavior in addictions

Our ability to measure the cognitive components of complex decision-making across species has greatly facilitated our understanding of its neurobiological mechanisms. One task in particular, reversal learning, has proven valuable in assessing the inhibitory processes that are central to executive control. Reversal learning measures the ability to actively suppress reward-related responding and to disengage from ongoing behavior, phenomena that are biologically and descriptively related to impulsivity and compulsivity. Consequently, reversal learning could index vulnerability for disorders characterized by impulsivity such as proclivity for initial substance abuse as well as the compulsive aspects of dependence. Though we describe common variants and similar tasks, we pay particular attention to discrimination reversal learning, its supporting neural circuitry, neuropharmacology and genetic determinants. We also review the utility of this task in measuring impulsivity and compulsivity in addictions. We restrict our review to instrumental, reward-related reversal learning studies as they are most germane to addiction. The research reviewed here suggests that discrimination reversal learning may be used as a diagnostic tool for investigating the neural mechanisms that mediate impulsive and compulsive aspects of pathological reward-seeking and -taking behaviors. Two interrelated mechanisms are posited for the neuroadaptations in addiction that often translate to poor reversal learning: frontocorticostriatal circuitry dysregulation and poor dopamine (D2 receptor) modulation of this circuitry. These data suggest new approaches to targeting inhibitory control mechanisms in addictions.
Self-assessment of pubertal stage in overweight children.

Objective For those with normal body habitus, self-assessments have been reported to yield Tanner stage ratings similar to those found by actual examinations. Little is known about whether such self-assessments are accurate in obese children. We therefore determined the reliability of Tanner stage self-assessments in both nonobese and obese children. Methods We studied 244 children age 6 to 12 years, 135 girls and 109 boys, 41% of whom were obese (body mass index > or =95th percentile for age and gender). Girls rated both breast and pubic hair development and boys rated pubic hair development using a standardized series of drawings accompanied by explanatory text. After self-ratings were completed, a pediatric endocrinologist or trained nurse practitioner who was blinded to subjects' self-ratings examined each subject. Results Self-ratings of breast Tanner stage were concordant with actual stage in 48%, overestimated in 25%, and underestimated in 27% of nonobese girls. By contrast, breast Tanner stage was overestimated by 38% of obese girls and was underestimated by only 12%. On average, obese girls overestimated actual Tanner breast stage by 0.47 +/- 0.9 stages. Pubic hair ratings were largely concordant with actual pubic hair stage in both obese and nonobese girls. Both nonobese and obese boys significantly overestimated actual Tanner pubic hair stage, by 0.51 +/- 1.1 stages and 0.31 +/- 0.8 stages, respectively. Conclusions We conclude that, in children 6 to 12 years of age, self-assessment cannot be used to determine reliably the breast Tanner stage of obese girls or the pubic hair stage of boys.
Membership matters: comparing members and non-members of NIPF owner organizations in southwest Wisconsin, USA

Abstract We surveyed members of two nonindustrial private forest (NIPF) owner organizations and non-members in southwest Wisconsin to learn their views and experiences on a range of forest ownership and management issues. The two organizations were the Sustainable Woods Cooperative (SWC) and the Wisconsin Woodland Owners Association (WWOA). Our survey yielded 503 completed questionnaires and a useable response rate of 69.5%. Members and non-members differed little in terms of perceived benefits of forest ownership, concerns over potential barriers to management, recent timber harvest activities and confidence in their management skills. However, members were more likely than non-members to have engaged in a variety of management activities during the last 3 years and more willing to consider future cross-boundary arrangements to benefit land stewardship. Between WWOA and SWC members, there were only two discernable differences, but the organizations are philosophically and structurally different. Given the voluntary nature of participation, no single organization can likely appeal to all owners. Yet, as the importance of landscape-scale management and biodiversity conservation increase, NIPF owner organizations could provide a mechanism for promoting and coordinating cross-boundary forest management practices.
Fabrication of polyamide thin-film nano-composite (PA-TFN) membrane with hydrophilized ordered mesoporous carbon (H-OMC) for water purifications

To enhance the performance of thin-film composite (TFC) membranes, nano-fillers are often used as additives in the polymerization process. Nano-fillers have to be hydrophilic to be dispersed in the aqueous phase to make thin-film nano-composite membrane (TFN) by interfacial polymerization. In this study, hydrophilized ordered mesoporous carbons (H-OMCs) were explored for TFN preparation. H-OMC was prepared from silica template, and argon atmospheric pressure plasma (APP) was applied to enhance surface hydrophilicity. m-Phenylenediamine (MPD) with trimesoyl chloride (TMC) was polymerized to make polyamide (PA) thin-film layer. The results indicated that 5% loading of H-OMCs increased membrane surface hydrophilicity, wettability and pure water permeability. Measurement of bovine serum albumin (BSA) adsorption on the membranes showed that with increasing H-OMCs loading, BSA adsorption was decreased. The enhanced membrane surface hydrophilicity might have contributed to the decreased BSA adsorption. With increasing amounts of H-OMCs up to 6%, rejection of monovalent ion (NaCl) was reduced from 68% to approximately 50%, but the rejection of divalent ions (Na2SO4) decreased only slightly from 94% to around 90%. Incorporation of the H-OMCs into the thin-film layer of the membrane did not change solution permeability in NaCl solution and slightly increased the solution permeability with Na2SO4. Overall, surface hydrophilicity, electrical properties and porous structure of the thin-films are significant factors limiting protein adsorption and enhancing membrane performances.
Perinatal insults and epilepsy

To review the relationship between seizures occurring during the perinatal period with subsequent development of epilepsy.
Cross-Conjugated Polymers with Large Two-Photon Absorption Cross-Sections for Metal Ion Sensing

The synthesis and metal ion sensing properties of two new cross-conjugated polymers, poly[(9,9-di-n-hexylfluorene-2,7-diyl)-alt-co-(2-(4-(N,N-(dibutylamino)styryl)benzene)-1,4-diyl)] (P1) and poly[(9,9-di-n-hexylfluorene-2,7-diyl)-alt-co-(2,5-bis(4- (N,N-(dibutylamino)styryl)benzene)-1,4-diyl)] (P2) are reported. These two polymers show very different sensing characteristics from those observed for linear conjugated polymers. Upon binding with different metal ions, P1 and P2 show clear intensity changes and large shift of their fluorescence emission peaks. This combined response significantly improves their binding selectivity. Moreover, the donor-π-bridge-donor (D-π-D) conjugated side chain motifs on P2 endow it with efficient two-photon absorbing (2PA) property. This allows it to be used in two-photon laser scanning microscopy and sensing.
Biological and chemical differences among proteins having reaginic activity

Abstract The reaginic properties of eleven human sera and/or their chromatographic fractions were examined with the use of physicochemical and biological methods. Proteins with reaginic activity were found to be markedly heterogeneous with regard to their elution characteristics from DEAE columns and with respect to their skin-fixing properties. Certain differences were also noted with respect to the degree of sensitivity of these proteins to sulfhydryl splitting agents. It remains to be learned if the heterogeneity demonstrated in these experiments is compatible with the concept that reaginic activity is associated with a single class of immunoglobulins.
Efficiency of phase conjugation for highly scattered light

Abstract We present experiments demonstrating reciprocity for conjugation of highly scattered light; if a fraction η of the total scattered light is incident on a phase-conjugate mirror having reflectivity ϱ, then a fraction ϱ η2 returns back through the scatterer as a phase-conjugate wave, with the remaining fraction ϱ (η−η2) being lost due to scattering. Low efficiency results from inability to gather a large fraction of scattering, but the efficiency is higher than is possible without conjugation.
Thermal Conductivity Measurements of Semitransparent Single-Walled Carbon Nanotube Films by a Bolometric Technique

We introduce a new technique for measurement of the thermal conductivity of ultrathin films of single-walled carbon nanotubes (SWNTs) utilizing IR radiation as heat source and the SWNT film as thermometer. The technique is applied to study the temperature dependence of the thermal conductivity of an as-prepared SWNT film obtained in the electric arc discharge process and a film of purified SWNTs prepared by vacuum filtration. The interplay between thermal and electrical transport in SWNT networks is analyzed in relation to the type of intertube junctions and the possibility of optimizing the thermal and electrical properties of SWNT networks for specific applications is discussed.
Integrating skill acquisition and perspective taking capacity in the development of leaders

This essay integrates approaches from three literatures to develop a model of leader development. Kanfer and Ackerman's (1989) episodic model of skill acquisition is combined with Kegan's approach to adult development to encompass development of transactional and transformational leadership. Importantly, feedback mechanisms are added to explain changes in individuals'intellectual capacities, values, and beliefs over time. This framework provides a summary of what is known about the processes underlying developmental change in how leaders understand and act on their environment and provides specific directions for future research.
Caenorhabditis elegans Muscleblind homolog mbl-1 functions in neurons to regulate synapse formation.

Background The sequestration of Muscleblind splicing regulators results in myotonic dystrophy. Previous work on Muscleblind has largely focused on its roles in muscle development and maintenance due to the skeletal and cardiac muscle degeneration phenotype observed in individuals with the disorder. However, a number of reported nervous system defects suggest that Muscleblind proteins function in other tissues as well.
A tripeptidyl ensemble perspective of interactive control of growth hormone secretion.

Current investigational tools in molecular biology, biochemistry and integrative physiology have revealed an increasing array of signals that influence growth hormone (GH) secretion. The present perspective combines these factors under a simplified final-common pathway model of threefold joint control by GH-releasing hormone, GH-releasing peptide/ghrelin and somatostatin. This concept is highlighted from the viewpoint of sex steroid- and age-dependent modulation of the peptide trilogy listed above.
Differential regulation of liver P‐450III cytochromes in choline‐deficient rats: Implications for the erythromycin breath test as a parameter of liver function

Progressive liver fibrosis in rats develops when they are fed a diet deficient in choline. This diet also results in a pronounced and selective decrease in the liver microsomal content of a phase I drug—metabolizing enzyme belonging to the cytochrome P-450III gene family. Because P-450III cytochromes characteristically catalyze the N-demethylation of erythromycin, we believed that the production of breath CO2 from erythromycin would be dramatically reduced in choline-deficient rats. However, when 12 choline-deficient rats were compared with 9 control rats, the reduction in CO2 production from erythromycin (mean decrease 71%) was essentially identical to that from aminopyrine (mean decrease 69%), a substrate believed to be metabolized normally by the hepatocyte in fibrotic liver disease. Furthermore, we found that the relative erythromycin and aminopyrine demethylase activities were comparable when measured in vitro in liver microsomes prepared from the choline-deficient rats. To determine the molecular basis for the erythromycin demethylase activity in the choline-deficient rats, the liver microsomes were subjected to immunoblot analysis using a variety of polyclonal and monoclonal antibodies capable of distinguishing individual P-450III—related proteins. Our studies confirm that a major erythromycin demethylase belonging to the P-450III family, termed P-450p, was greatly reduced in the choline-deficient rat liver. However, the specific concentration of a second P-450p—related protein was essentially normal and that of a third P-450p—related protein was actually increased in the choline-deficient rat liver. These changes occurred over weeks and months on the choline-deficient diet and are not consistent with “feminization” of the liver. The P-450p—related proteins appeared to catalyze erythromycin demethylase activity because antibodies recognizing them inhibited the majority (62%) of this activity in choline-deficient rat microsomes. Finally, RNA extracted from choline-deficient rat livers was hybridized on Northern blots with synthetic oligonucleotide probes that identify the only two known rat P-450III cDNAs, PCN-1 and PCN-2. Prolonged choline deficiency appeared to have no consistent effects on expression of these RNA species. We conclude that despite the down-regulation of a major erythromycin demethylase, this catalytic activity is relatively preserved in the choline-deficient rat, at least in part because of differential regulation of P-450III cytochromes. Erythromycin therefore appears to offer little advantage over aminopyrine as a substrate for assessing liver function in this model of chronic liver disease. (HEPATOLOGY 1990;12:1371–1378).
Methyltransferases mediate cell memory of a genotoxic insult

Characterization of the direct effects of DNA-damaging agents shows how DNA lesions lead to specific mutations. Yet, serum from Hiroshima survivors, Chernobyl liquidators and radiotherapy patients can induce a clastogenic effect on naive cells, showing indirect induction of genomic instability that persists years after exposure. Such indirect effects are not restricted to ionizing radiation, as chemical genotoxins also induce heritable and transmissible genomic instability phenotypes. Although such indirect induction of genomic instability is well described, the underlying mechanism has remained enigmatic. Here, we show that mouse embryonic stem cells exposed to γ-radiation bear the effects of the insult for weeks. Specifically, conditioned media from the progeny of exposed cells can induce DNA damage and homologous recombination in naive cells. Notably, cells exposed to conditioned media also elicit a genome-destabilizing effect on their neighbouring cells, thus demonstrating transmission of genomic instability. Moreover, we show that the underlying basis for the memory of an insult is completely dependent on two of the major DNA cytosine methyltransferases, Dnmt1 and Dnmt3a. Targeted disruption of these genes in exposed cells completely eliminates transmission of genomic instability. Furthermore, transient inactivation of Dnmt1, using a tet-suppressible allele, clears the memory of the insult, thus protecting neighbouring cells from indirect induction of genomic instability. We have thus demonstrated that a single exposure can lead to long-term, genome-destabilizing effects that spread from cell to cell, and we provide a specific molecular mechanism for these persistent bystander effects. Collectively, our results impact the current understanding of risks from toxin exposures and suggest modes of intervention for suppressing genomic instability in people exposed to carcinogenic genotoxins.
Fire Resistance of Wood Joist Floor Assemblies

This paper discusses the factors that affect the fire resistance performance of lightweight wood frame unrestrained floor assemblies protected with Type X gypsum board ceiling finishes. Twenty-two fire resistance experiments were conducted on full-scale load-bearing wood joist floor assemblies using the ULC standard fire exposure time–temperature curve that is similar to ASTM E119 standard. Parameters investigated in this study include the effects of gypsum board screws spacing from board edges, insulation installation, insulation type, joist spacing for assemblies with gypsum board attached to resilient channels, joist depth, resilient channel installation, resilient channel spacing, sub-floor topping, number of sub-floor layers, and load magnitude. The impact of these parameters on the fire resistance of wood joist frame floor assemblies is discussed. The fire resistance of wood frame floors appears essentially to be governed by the gypsum board screw spacing from the board edges and the type of insulation in assemblies with one layer of gypsum board and by the resilient channel spacing and the gypsum board screw spacing from the board edges in assemblies with two layers of gypsum board. The effects of other parameters in assemblies with two layers of gypsum board such as the joist spacing where the gypsum boards are attached to resilient channels, installation of resilient channels, insulation installation, insulation type, adding gyp-crete topping above the sub-floor and number of sub-floor layers on fire resistance are relatively insignificant.
Telomere attrition and Chk2 activation in human heart failure.

The “postmitotic” phenotype in adult cardiac muscle exhibits similarities to replicative senescence more generally and constitutes a barrier to effective restorative growth in heart disease. Telomere dysfunction is implicated in senescence and apoptotic signaling but its potential role in heart disorders is unknown. Here, we report that cardiac apoptosis in human heart failure is associated specifically with defective expression of the telomere repeat- binding factor TRF2, telomere shortening, and activation of the DNA damage checkpoint kinase, Chk2. In cultured cardiomyocytes, interference with either TRF2 function or expression triggered telomere erosion and apoptosis, indicating that cell death can occur via this pathway even in postmitotic, noncycling cells; conversely, exogenous TRF2 conferred protection from oxidative stress. In vivo, mechanical stress was sufficient to down-regulate TRF2, shorten telomeres, and activate Chk2 in mouse myocardium, and transgenic expression of telomerase reverse transcriptase conferred protection from all three responses. Together, these data suggest that apoptosis in chronic heart failure is mediated in part by telomere dysfunction and suggest an essential role for TRF2 even in postmitotic cells.
AN APPROACH TO THE QUANTITATION OF IMMUNOGENIC ANTIGEN

Using passively administered isotope-labeled anti-KLH to suppress the antibody response of rabbits to KLH, we have attempted to estimate the amount of antigen actually involved in stimulating antibody formation. Single and paired label tracer studies of passively administered anti-KLH IgG indicated that from 0.7 to 2.9 µg were utilized or involved by the antigen in the course of a 90% suppression of the response to 2 mg KLH. Tracer studies of labeled anti-KLH F(ab')2 fragments revealed the retention of from 2 to 3 µg of these fragments in the entire rabbit during a 60% suppression of the response to 1 mg KLH. Based on previously determined ratios of mixtures of KLH and suppressive amounts of anti-KLH in adjuvant, the antibody utilization data were converted to the probable amount of antigen or immunogen involved. It appears that after an injection of 2 mg of KLH approximately 0.2–0.5 µg of antigen persisted and reacted with antibody given 24 hr later. Since all of this persisting, reactive antigen may not be immunogenic, the above estimate of immunogen is probably high, but may serve to establish upper limits for the amounts of immunogen involved in stimulating antibody formation and provide a meaningful frame of reference for antigen tracer studies.
Accurate calculations of bond-breaking energies in C60 using the three-layered ONIOM method

Abstract The three-layered ONIOM method was used to calculate the adiabatic singlet–triplet (S0→T1) and singlet–quintet (S0→Q) energy splittings in C60 fullerene. The ONIOM(G2MS:ROMP2/6-31G(d):ROHF/6-31G) calculation gives a value of 35.1 for the S0→T1 splitting, in good agreement with the experimental value of 36.1 kcal/mol. For accurate bond energies, for which typically a coupled-cluster level of theory is required, the ONIOM appears to be an ideal method for large molecules. The S0→Q splitting, corresponding to the complete breaking of a double bond in C60, is predicted to be 252 kcal/mol, a large value due to the severe strain and the disruption of conjugation in the product.
Commodity booms, coalitional politics and government intervention in credit markets

ABSTRACTScholars of the ‘resource curse’ increasingly agree that strong institutions can help countries avoid the pitfalls associated with abundant natural resource wealth. This paper argues that certain political coalitions can serve a similar function in the context of weak institutions. To explicate this argument, this paper examines how international commodity booms regularly create credit demand that surpasses available supply, often impelling exporters to seek government assistance with obtaining credit. Four case studies illustrate how coalitional politics dictated governmental responses to such demands. Where exporters were members of the ruling coalition (Chile and Argentina), their needs sparked credit sector reform and government help to access credit. Where exporters were excluded from political power (Colombia and Nigeria), government policy hindered their economic goals. These findings suggest that the resource curse may pivot on coalitional politics in important respects. The paper conclude...
DIFFERENCES IN THE BINDING OF COENZYME TO L-3-HYDROXYACYL-COENZYME A DEHYDROGENASE IN THE CRYSTALLINE STATE AND IN SOLUTION

L-3-Hydroxyacyl coenzyme A dehydrogenase (L-3hydroxyacyl-CoA:NAD oxidoreductase; EC 1 .l .1.35) is a mitochondrial enzyme involved in the beta oxidation of fatty acids. The enzyme, as isolated from pig heart muscle, hasM, 67 000 and contains two identical subunits [l]. The amino acid sequence has recently been completed and appears to have little homology with other dehydrogenases [2]. Like many other dehydrogenases, L-3-hydroxyacyl coenzyme A dehydrogenase @-HADH) utilizes NAD-NADH as cofactors. However, unlike many other dehydrogenases, the structure of its substrate, L-3-hydroxyacyl coenzyme A, resembles the cofactor, NAD. Structural studies of the enzyme should prove to be of interest in that both the substrate and coenzyme binding sites might be expected to contain binding domains for adenine nucleotide moieties. In addition, the active site of /3-HADH must accommodate the varying acyl chain lengths of fatty acids that are metabolized through the beta oxidation cycle. In order to determine the molecular structure of P-HADH, an X-ray crystallographic study is being carried out. From an electron density map at low resolution, the tentative location of the two dimers contained in the asymmetric unit has been determined [3]. In addition, crystallographic studies aimed at locating the binding site of NAD have also been undertaken. Difference Fourier maps between the holo- and apo-forms of the crystalline enzyme yield only 1 major NAD binding site/dimer. This apparent asymmetry in NAD binding to crystalline /3-HADH prompted a study of the binding characteristics of coenzyme to fl-HADH in solution. This communication reports the comparison of the X-ray and solution studies.
A nonlinear equation with piecewise constant argument

Oscillation, nonoscillation, asymptotical stability and dynamical behavior of solution of equation are studied.
Disparities in chlamydia testing among young women with sexually transmitted infection symptoms.

Background: Diagnostic chlamydia testing is recommended for all young women demonstrating sexually transmitted infection (STI) symptoms. Differential testing among symptomatic women may contribute to disparities in chlamydia rates. Our objective was to determine whether providers test young women with STI symptoms for chlamydia differently by age, race/ethnicity, or insurance status, and whether testing patterns differ by documentation of previous STI. Methods: Retrospective cohort analysis using electronic medical records and billing data of women 14 to 25 years old with one or more diagnostic or procedure codes indicative of STI symptoms (N = 61,498 women). Random effects logistic regression analysis was performed to assess the odds of chlamydia testing given a woman presented for a nonpregnancy-related visit with STI symptoms. All analyses controlled for history of STI, setting, and year, and adjusted for within-person correlation. Results: A chlamydia test was performed in 38% of visits with codes indicating STI symptoms. Women aged 19 were less likely to be tested than women aged 18 to 19, with young women aged 14 to 15 having the lowest odds of being tested (Odd Ratio [OR]: 0.52). Providers were more likely to test minority (OR black : 2.87; OR Latina : 2.10) compared with white women. Women were also more likely to be tested if they had public insurance (OR: 2.41) or were self-pay (OR: 2.35) compared with if they had private insurance. Women aged 14 to 15 and 16 to 17 with prior history of STI had increased odds of chlamydia testing (OR: 1.79 and 1.43, respectively) compared with women aged 18 to 19, changing the overall direction of association compared with women with no history of STI. The odds of testing were dramatically reduced for minority and nonprivately insured young women with history of STI, although significant differences persisted. Conclusions: Provider chlamydia testing differs by age, race/ethnicity, and insurance status when a woman presents with STI symptoms and no prior history of STI. This bias may contribute to higher reported rates of chlamydia among younger, minority, and poor women.
Do Personalization and Postage Make a Difference on Response Rates to Surveys of Professional Populations

The purpose of this study was to test the effectiveness of two techniques for increasing response rates to mailed questionnaires, namely, type of covering letter salutation (handwritten vs typed) and return postage (metered vs nonmetered). Surveys were sent to 300 randomly selected members of the National Council for Measurement in Education. A 2 × 2 factorial analysis of variance showed typed salutations were more effective than handwritten salutations in eliciting responses from this professional population. No differences in response rates were found between metered and nonmetered return envelopes.
Nanopatterning of atomic layer deposited Al:ZnO films using electron beam lithography for waveguide applications in the NIR region

We have demonstrated the nanopatterning of atomic layer deposited (ALD) Al:ZnO (AZO) films using electron beam lithography (EBL) for plasmonic waveguide applications. The influence of grains on repeatable planar nanostructures by nanolithography process was studied for annealed films in order to avoid effects of granularity. Our results demonstrate that the nanopatterning of AZO by the EBL technique is limited due to granularity of ALD grown AZO films. This finding suggests the limitations of ALD grown samples for optical applications where nanopatterns are fabricated by the EBL technique. Furthermore, the ALD grown films lose conductivity orders of magnitude on annealing.
Negative Pressure Pulmonary Hemorrhage

Negative pressure pulmonary edema, a well-recognized phenomenon, is the formation of pulmonary edema following an acute upper airway obstruction (UAO). To our knowledge, diffuse alveolar hemorrhage has not been reported previously as a complication of an UAO. We describe a case of negative pressure pulmonary hemorrhage, and we propose that its etiology is stress failure, the mechanical disruption of the alveolar-capillary membrane.