cssi/SciSciGPT-SciSciNet huggingface dataset:
Applications of the Finite Element Method to Sheet Metal Flanging Operations

This paper summarizes several recently developed finite element models for numerical analysis of stretch flanging operations in sheet metal forming. For flange geometries which can be represented by a ruled surface, the forming operation is shown to be adequately modelled by using an elastic-plastic, in-plane deformation finite element analysis provided that the ruled surface is developable. The obvious advantage of an in-plane model is that numerical solutions can be more easily obtained as compared to those by an out-of-plane model. Calculations for the flanging of a circular tube and a notched stretch flange are discussed in detail. The application of the in-plane model has been recently extended to the case where the ruled surface is non-developable. As an example, calculated strain distributions in a flange formed by twisting are presented. For flange geometries which cannot be represented by a ruled surface, modelling of the forming operation must include out-of-plane deformation and friction contact as well. Numerical results for the forming of an offset flange by using an axisymmetric finite element model were obtained, and compared with experimental data. Effects of the tool friction and material parameters on the forming operation are discussed.
Modern Concepts of Intensive Monitoring in Epilepsy

Intensive monitoring (prolonged simultaneous EEG and video recording) has proved an effective means of establishing the diagnosis in patients with intractable epilepsy or enigmatic attacks and of l...
Endothelial pyruvate kinase M2 maintains vascular integrity

The M2 isoform of pyruvate kinase (PKM2) is highly expressed in most cancer cells, and has been studied extensively as a driver of oncogenic metabolism. In contrast, the role of PKM2 in nontransformed cells is little studied, and nearly nothing is known of its role, if any, in quiescent cells. We show here that endothelial cells express PKM2 almost exclusively over PKM1. In proliferating endothelial cells, PKM2 is required to suppress p53 and maintain cell cycle progression. In sharp contrast, PKM2 has a strikingly different role in quiescent endothelial cells, where inhibition of PKM2 leads to degeneration of tight junctions and barrier function. Mechanistically, PKM2 regulates barrier function independently of its canonical activity as a pyruvate kinase. Instead, PKM2 suppresses NF-kB and its downstream target, the vascular permeability factor angiopoietin 2. As a consequence, loss of endothelial cell PKM2 in vivo predisposes mice to VEGF-induced vascular leak, and to severe bacteremia and death in response to sepsis. Together, these data demonstrate new roles of PKM2 in quiescent cells, and highlight the need for caution in developing cancer therapies that target PKM2.
Optimal energy-emission management in hybrid AC-DC microgrids with vehicle-2-grid technology

This article focuses on the optimal operation management challenges in hybrid AC-DC microgrids considering optimal feeder switching, renewable energy sources, and plug-in electric vehicles. In comparison with the traditional hybrid AC-DC microgrid concept, the reconfigurable hybrid AC-DC microgrids provide more flexibility for better supporting consumers and reducing the operation costs through the remotely controlled switches. In addition, the reconfigurable structure of the hybrid microgrid along with the vehicle-to-grid technology supports the high penetration of plug-in electric vehicles by changing their role from only consuming loads into mobile storages. The proposed problem is prepared as a constrained multi-objective problem optimizing both cost and emission objectives. Due to the high complication and nonlinearity of the problem, an effective optimization algorithm called the theta-crow search algorithm is developed to solve the problem optimally. Also, a stochastic framework based on the point estimate method is used to model the high uncertainties of the problem. The high reliable and satisfying performance of the new method is shown on a test AC-DC microgrid.
Bremsstrahlung from the interaction of short laser pulses with dielectrics

An intense, short laser pulse incident on a transparent dielectric can excite electrons from the valence to the conduction band. As these electrons undergo scattering, both from phonons and ions, they emit bremsstrahlung. Here we present a theory of bremsstrahlung emission appropriate for the interaction of laser pulses with dielectrics. Simulations of the interaction, incorporating this theory, illustrate characteristics of the radiation (power, energy, and spectra) for arbitrary ratios of electron collision frequency to radiation frequency. The conversion efficiency of laser pulse energy into bremsstrahlung depends strongly on both the intensity and duration of the pulse, saturating at values of about 10^{-5}. Depending on whether the intensity is above or below the damage threshold of the material, the emission can originate either from the surface or the bulk of the dielectric, respectively. The bremsstrahlung emission may provide a broadband light source for diagnostics.
Acid-Base Disorders in Liver Disease

The role of the liver in acid-base regulation is often neglected because of the importance given to the lungs and kidneys. This negligence is partly related to few studies of acid-base disorders in liver disease. In Chap. 2, the roles of the lungs and kidneys in acid-base regulation were discussed. In this chapter, a brief discussion of the role of the liver in acid-base balance and its disorders in liver disease are presented. The role of the liver in acid-base balance is divided into four categories.
Approximating trigonometric functions for posits using the CORDIC method

Posit is a recently proposed representation for approximating real numbers using a finite number of bits. In contrast to the floating point (FP) representation, posit provides variable precision with a fixed number of total bits (i.e., tapered accuracy). Posit can represent a set of numbers with higher precision than FP and has garnered significant interest in various domains. The posit ecosystem currently does not have a native general-purpose math library. This paper presents our results in developing a math library for posits using the CORDIC method. CORDIC is an iterative algorithm to approximate trigonometric functions by rotating a vector with different angles in each iteration. This paper proposes two extensions to the CORDIC algorithm to account for tapered accuracy with posits that improves precision: (1) fast-forwarding of iterations to start the CORDIC algorithm at a later iteration and (2) the use of a wide accumulator (i.e., the quire data type) to minimize precision loss with accumulation. Our results show that a 32-bit posit implementation of trigonometric functions with our extensions is more accurate than a 32-bit FP implementation.
Comparison of inpatient versus post-discharge venous thromboembolic events after spinal surgery: A single institution series of 6869 consecutive patients.

Abstract Study design retrospective chart review. Objective We aimed to determine the perioperative risk factors that lead to inpatient or post-discharge venous thromboembolism (VTE) events after spinal surgery. Summary of background data While many studies relate the risk factors in a post-surgical setting to the incidence of VTE, this study aims to separate these VTE into inpatient and post-discharge categories to examine timing and risk factors. Methods We analyzed 6869 patients from 2009 to 2015 using Current Procedural Technology codes from a single tertiary academic institution. Patients were stratified based on occurrence and setting of VTE then controlled for perioperative characteristics with exclusion criteria being patients undergoing minor spine surgeries or secondary procedures. Results In 170 VTE events, these factors were associated with increased risk for: Inpatient DVT only: IVC filter (OR 6.380 [3.414−11.924]), longer length of hospital stay (OR 1.083 [1.047−1.120]), a prior history of DVT (OR 3.640 [1.931−6.856]). Post-discharge DVT only: history of PE (OR 45.142 [6.785−300.351]), having a corpectomy (OR 26.670 [3.477−204.548]), and having an osteotomy (OR 18.877 [1.129−315.534]). Inpatient PE only: surgery >4 h (OR 30.820, p 500cc (OR 2467.798, p = 0.002). Time to onset of VTE events was significantly longer for patients undergoing osteotomy (7.43 days) than for patients with fracture (4.28 days), which is consistent with our findings that fracture was an independent predictor of inpatient VTE, and osteotomy was an independent predictor of post-discharge VTE (p = 0.018). Conclusions Time-to-VTE varies between types of surgeries. Some risk factors are independently associated with VTE at all times during the 30-day postoperative period, while other factors are only associated with either inpatient or post-discharge VTE. Those patients with high-risk features for post-discharge VTE merit increased study for thromboprophylaxis management.
Gastrointestinal health: An investigation of mediating effects on mood and quality of life.

High prevalence rates for depression, anxiety, and gastrointestinal (GI) symptoms are found in emerging adults. However, the consequences of mood, anxiety, and GI health on health-related quality o...
Keeping Nanomedicine on Target.

A principal purpose of targeting or triggering is to improve the active agents’ therapeutic indices by preferentially increasing their concentrations at the desired site of effect.
Nonoverlap proportion and the representation of point-biserial variation

We consider the problem of constructing a complete set of parameters that account for all of the degrees of freedom for point-biserial variation. We devise an algorithm where sort as an intrinsic property of both numbers and labels, is used to generate the parameters. Algebraically, point-biserial variation is represented by a Cartesian product of statistical parameters for two sets of [Formula: see text] data, and the difference between mean values (δ) corresponds to the representation of variation in the center of mass coordinates, (δ, μ). The existence of alternative effect size measures is explained by the fact that mathematical considerations alone do not specify a preferred coordinate system for the representation of point-biserial variation. We develop a novel algorithm for estimating the nonoverlap proportion (ρpb) of two sets of [Formula: see text] data. ρpb is obtained by sorting the labeled [Formula: see text] data and analyzing the induced order in the categorical data using a diagonally symmetric 2 × 2 contingency table. We examine the correspondence between ρpb and point-biserial correlation (rpb) for uniform and normal distributions. We identify the [Formula: see text], [Formula: see text], and [Formula: see text] representations for Pearson product-moment correlation, Cohen's d, and rpb. We compare the performance of rpb versus ρpb and the sample size proportion corrected correlation (rpbd), confirm that invariance with respect to the sample size proportion is important in the formulation of the effect size, and give an example where three parameters (rpbd, μ, ρpb) are needed to distinguish different forms of point-biserial variation in CART regression tree analysis. We discuss the importance of providing an assessment of cost-benefit trade-offs between relevant system parameters because 'substantive significance' is specified by mapping functional or engineering requirements into the effect size coordinates. Distributions and confidence intervals for the statistical parameters are obtained using Monte Carlo methods.
Does Tobacco Screening in Youth Primary Care Identify Youth Vaping

Abstract Purpose The purpose of this study was to evaluate the sensitivity of a tobacco use screening question, modified to include the word “e-cigarette,” in detecting past 12-month nicotine vaping and past 12-month tobacco product use inclusive of nicotine vaping, among adolescent primary care patients. Methods We conducted secondary analysis of data from a pilot trial of adolescent substance use screening and brief intervention in pediatric primary care. Participants were patients aged 12–18 years (N = 278) presenting for annual well-visits at five practices in Massachusetts in 2015–2017. Study measures consisted of a clinical brief screener item and tobacco/electronic cigarette items on a confidential, self-administered research questionnaire (criterion measure). Results The clinical brief screener item identified 24 of 30 adolescents with past 12-month tobacco use (sensitivity 80%); 15 of 30 with past 12-month electronic cigarette use (sensitivity 50.0%), and 25 of 42 with tobacco and/or electronic cigarette use (sensitivity 59.5%). Conclusions These findings support the need to develop and test a screening measure that is sensitive for capturing electronic cigarette use.
A pseudoproxy assessment of why climate field reconstructionmethods perform the way they do in time and space

Abstract. Spatiotemporal paleoclimate reconstructions that seek to estimate climate conditions over the last several millennia are derived from multiple climate proxy records (e.g. tree rings, ice cores, corals, and cave formations) that are heterogeneously distributed across land and marine environments. Assessing the skill of the methods used for these reconstructions is critical as a means of understanding the spatiotemporal uncertainties in the derived reconstruction products. Traditional statistical measures of skill have been applied in past applications, but they often lack formal null hypotheses that incorporate the spatiotemporal characteristics of the fields and allow for formal significance testing. More recent attempts have developed assessment metrics to evaluate the difference of the characteristics between two spatiotemporal fields. We apply these assessment metrics herein to results from synthetic reconstruction experiments based on multiple climate model simulations to assess the skill of four reconstruction methods. We further interpret the comparisons using analysis of Empirical Orthogonal Functions that represent the noise-filtered climate field. The features of climate models and reconstruction methods identified in this paper demonstrate more detailed assessments of reconstruction methods and point to important areas of testing and improving real-world reconstruction methods.
Developing Children's Literacy Learning Through Skillful Parent–Child Shared Book Readings

The purpose of this study was to examine children’s reading performance and parents’ use of reading support strategies throughout their participation in a family literacy program. In the program sessions, parents learned strategies to promote discussions around reading and strategies to support children at the word level. The program occurred in a second-grade and third-grade classroom with a culturally and linguistically diverse student population. This case study, with multiple embedded units, focuses on four parent–child dyads who participated in the program. Audio recordings of the home readings were examined for parents’ strategy use across weeks, as well as changes in children’s reading performance. Analyses of audio recorded parent–child readings showed that parents used both discussion and oral reading strategies to support their children’s readings, and had various responses to the program training. Likewise, children showed gains in terms of reading rate, accuracy, and fluency as well as on independent reading measures, from the beginning of the program period to the end.
Human Capital, Capital Stock Formation, and Economic Growth: A Panel Granger Causality Analysis

Fostering educational practices, increasing enrollments rate, and improving learning is a central part of most economic development strategies. Most economists from the 20th and early 21st century see the idea of increasing the public’s aggregate per capita investment in human capital as a controversial topic; because the expansion of education has not guaranteed improved economic conditions in some regions. The variables used in the study include 14 Latin American countries that have been analyzed, and the results show a strong causal relationship between real gross domestic product per capita–purchasing power parity and human capital. Although the study doesn’t find a direct Granger causal relationship moving from human capital to real gross domestic product per capita-purchasing power parity, there is an indirect Granger causal relationship between our variables of interest. The association can be found in the bidirectional Granger causal relationship between human capital and trade balance.
Determinants and trends of COVID-19 vaccine hesitancy and vaccine uptake in a national cohort of U.S. adults: A longitudinal study

BackgroundVaccine hesitancy in the U.S. may limit the potential to alleviate the public health threat caused by the COVID-19 pandemic. MethodsWe estimated trends in and correlates of vaccine hesitancy, and its association with subsequent vaccine uptake among 5,085 United States adults from the CHASING COVID Cohort study, a national longitudinal study. Trends in willingness to vaccinate were examined longitudinally in three rounds of interviews from September to December 2020. We assessed correlates of willingness to vaccinate in December 2020. We also estimated the association between willingness to vaccinate in December 2020 and subsequent vaccine uptake in February 2021. ResultsVaccine hesitancy and resistance decreased from 51% and 8% in September 2020 to 35% and 5% in December 2020, respectively. Compared to Non-Hispanic (NH) White participants, NH Black and Hispanic participants had higher adjusted odds ratios (aOR) for both vaccine hesitancy (aOR: 3.3 [95% CI: 2.6, 4.2] for NH Black and 1.8 [95% CI: 1.5, 2.2] for Hispanic) and vaccine resistance (aOR: 6.4 [95% CI: 4.3, 9.4] for NH Black and 1.9 [95% CI: 1.3, 2.7] for Hispanic). Willingness to vaccinate was associated with lower odds of vaccine uptake among 65+ year olds (aOR: 0.4, 95% CI: 0.3, 0.6 for hesitancy; aOR: 0.1, 95% CI: 0.01, 0.6 for resistance) and healthcare workers (aOR: 0.2, 95% CI: 0.1, 0.3 for hesitancy; aOR: 0.04, 95% CI: 0.006, 0.2 for resistance). ConclusionsAwareness and distribution efforts should focus on vaccine hesitant vulnerable populations.
Costs, constraints and sexual trait elaboration

Much research on sexual selection focuses on evolutionary forces that drive sexual trait elaboration. Yet sexual traits are also shaped equally in their evolution by countervailing factors, namely costs and constraints, which curtail continued sexual trait elaboration. In this essay I consider the roles of these factors, particularly constraints, in curbing sexual trait expression and evolution. First, I review basic definitions of costs and constraints, with emphasis on the distinction between them. Second, I discuss operational strategies for identifying constraints on sexual traits, emphasizing the value of studies on mechanisms that underlie sexual trait expression. Third, I offer new speculations regarding the relative roles of costs and constraints over evolutionary timescales. In particular, I suggest that (1) during initial stages of trait elaboration, costs play dominant roles as countervailing factors, (2) for systems in which trait elaboration proceeds, constraints become increasingly influential as a countervailing co-factor alongside costs and (3) for nature's most elaborate sexual traits, constraints emerge as the most dominant countervailing factor, yet never to the point where costs are eliminated. Finally, I apply this new speculative framework in re-evaluating definitions of two categories of sexual signals that are often regarded as hinging on costs and constraints: handicap signals and index signals.
IL-6 promotes drug resistance through formation of polyploid giant cancer cells and stromal fibroblast reprogramming

To understand the role of polyploid giant cancer cells (PGCCs) in drug resistance and disease relapse, we examined the mRNA expression profile of PGCCs following treatment with paclitaxel in ovarian cancer cells. An acute activation of IL-6 dominated senescence-associated secretory phenotype lasted 2-3 weeks and declined during the termination phase of polyploidy. IL-6 activates embryonic stemness during the initiation of PGCCs and can reprogram normal fibroblasts into cancer-associated fibroblasts (CAFs) via increased collagen synthesis, activation of VEGF expression, and enrichment of CAFs and the GPR77 + /CD10 + fibroblast subpopulation. Blocking the IL-6 feedback loop with tocilizumab or apigenin prevented PGCC formation, attenuated embryonic stemness and the CAF phenotype, and inhibited tumor growth in a patient-derived xenograft high-grade serous ovarian carcinoma model. Thus, IL-6 derived by PGCCs is capable of reprogramming both cancer and stromal cells and contributes to the evolution and remodeling of cancer. Targeting IL-6 in PGCCs may represent a novel approach to combating drug resistance.
Evaluation of Collection and Extraction Methods for Mutagenesis Studies on Ambient Air Particulate

The extractable organics associated with air particles have been shown to be carcinogenic (Hueper et al., 1962; Leiter et al., 1942) and mutagenic in a short-term microbial bioassay (Lewtas Huisingh, 1980; Teranishi et al., 1977). The identification and characterization of the potentially hazardous chemical components associated with ambient air particles requires that efficient collection and extraction methods be developed and validated. It is important that the original chemical composition of the particle-bound organics be maintained through collection and extraction to establish that the bioassay results are directly relatable to the chemistry of the original organics as they exist on particles in the atmosphere. The particles of major interest are those that are in the inhalable (< 15 μm) or respirable (< 5 μm) size range and therefore can be trapped in the human respiratory tract. Several studies have shown that the organics associated with ambient air particles are more mutagenic in the smaller (respirable) particle size range (Huisingh, 1980; Teranashi et al., 1977).
Samuel Johnson, the Ossian Fraud, and the Celtic Revival in Great Britain and Ireland: An introductory survey of scholarship on Ossian : why literary truth matters

Ossian sublimest, simplest bard of all, Let English infidels M'Pherson call. Charles Churchill, A Prophecy of Famine (1763) Concerning Samuel Johnson, a very close friend affirmed that “no man had a more scrupulous regard for truth; from which, I verily believe, he would not have deviated to save his life.” No writer angered Johnson more than did James Macpherson for perpetrating what arguably became the most successful literary falsehood in modern history. With the monumental exception of his Lives of the English Poets (1779–81), Johnson's most notable literary undertaking in old age after his edition of Shakespeare (1765) involved debunking Macpherson's bogus poetry. Exposing Macpherson's fabricating ways was a fitting activity for an author ranked as England's greatest moralist. This book, therefore, is fundamentally a study about Johnson and Ossian , Johnson's interest in Gaelic culture and linguistics, and his involvement in a controversy smoldering throughout the British Isles for almost the final quarter-century of his life. The present chapter briefly reviews the enormous amount of scholarship published about Macpherson since 1800. The subsequent focus of attention lies on much of the pre-1800 critical response by Scottish, English, and Irish participants in a Celtic Revival, which unleashed national cultural wars over historical origins and political precedence for an ethnically mixed people. The contest over the authenticity of Macpherson's pseudo-Gaelic productions became a seismograph of the fragile unity within restive diversity of imperial Great Britain in the age of Johnson.
Processing and characterization of ferroelectric thin films in the Pb/sub 5/Ge/sub 3/O/sub 11/-PbZr/sub 0.5/Ti/sub 0.5/O/sub 3/ system

This work investigates the crystallization of pure Pb/sub 5/Ge/sub 3/O/sub 11/ (PG) and composition in the Pb/sub 5/Ge/sub 3/O/sub 11/-PbZr/sub 0.5/Ti/sub 0.5/O/sub 3/ (PG-PZT) system. PG is of interest due to its low processing temperatures and possible application as pyroelectric sensors and nonvolatile ferroelectric memories. Compositions in the PG-PZT system crystallize to form multiple ferroelectric phases at relatively low temperatures, potentially offering a unique combination of ferroelectric properties and processing conditions. Ferroelectric thin films in the PG-PZT system were fabricated on (111) Pt-coated silicon substrates using sol gel processing techniques. Rapid thermal processing was utilized to investigate the time/temperature dependencies of crystallization, phase transformations and orientation of both Pb/sub 5/Ge/sub 3/O/sub 11/ and PbZr/sub 0.5/Ti/sub 0.5/O/sub 3/. Pb/sub 5/Ge/sub 3/O/sub 11/ films with a thickness of 2000 /spl Aring/ crystallized with a c-axis orientation of greater than 90% when heat treated at 700/spl deg/C for 30 seconds.
Transcriptional regulation of cellular transformation.

Structurally and functionally altered transcription factors have been associated with many human neoplasms. A better understanding of these transcriptional defects has revealed new therapeutic opportunities.
A prevalent transversality theorem for Lipschitz functions

This paper provides a version of the transversality theorem for a class of Lipschitz functions of the form f: R" x C → R", where C is a convex subset of a normed vector space Z indexing the parameters in the problem. The set C may be infinite-dimensional, and the notion of generic used is the measure-theoretic notion of prevalence introduced by Hunt, Sauer and Yorke (1992) and Christensen (1974). This paper also provides some results on sensitivity analysis for solutions to locally Lipschitz equations.
Controlling Bacterial Wilt in Muskmelon with Perimeter Trap Cropping

Perimeter trap cropping (PTC) involves planting one or more rows of a cucurbit crop that is highly attractive to cucumber beetles around the border of a main cucurbit cash crop that is less attractive to the beetles. Cucumber beetles attempting to migrate into the field are concentrated in the relatively more attractive border crop, where they can be controlled by insecticides.
The Pharmacologic Effects of Recombinant, Human Colony-Stimulating Factors and Their Modulation by Theophylline

Study Objectives. To investigate the effect of colony-stimulating factors (CSFs) on drug metabolism using theophylline as a substrate (phase I), and to evaluate the influence of theophylline on endogenous serum cytokine concentrations (phase II). Design. Open-label, prospective study. Setting. The bone marrow transplant unit of a tertiary university teaching hospital. Patients. Thirty-seven women with breast cancer (28 phase I, 9 phase II). Interventions. Patients received aminophylline 0.58 mg/kg either as a 30-minute intravenous infusion before receiving recombinant CSFs or after several days of CSF therapy, just before high-dose chemotherapy (phase I) or as a continuous intravenous infusion after bone marrow transplantation (phase II). Measurements and Main Results. Clearance of theophylline was significantly higher after CSF administration (0.76 vs 0.99 ml/min/kg, p=0.019). Continuous infusion of aminophylline resulted in elevations of serum macrophage-CSF and interleukin-6. Conclusions. Administration of CSFs before autologous bone marrow transplantation for priming progenitor cells may alter drug metabolism. Studies should be conducted to evaluate the potential effects of CSFs on the disposition of chemotherapeutic agents.
Management of cancer of the oral cavity. The trend toward combined radiotherapy and surgery.

Summary Two hundred and twenty-one cases of squamous cancer of the oral cavity (tongue, floor of mouth, and mandibular alveolus) treated by three different methods, namely, surgery, radiation therapy, and combined therapy, are analyzed. A rationale of patient selection is presented, and a detailed analysis of the results is documented. All factors affecting survival are studied. Combined radiation therapy and surgery uniformly yielded the best survival in the sites studied.
Operative management of ruptured tubal pregnancy

Abstract Ruptured ectopic pregnancy constitutes a major gynecologic emergency and is responsible for a significant percentage of gynecologic mortality in the United States of America. From 1964 to 1971, 96 patients with ruptured tubal pregnancy were treated at the University of Kentucky Medical Center and affiliated hospitals. Of these patients, four had previous tubal pregnancies and five had prior tubal ligations; 41 had microscopic evidence of pelvic inflammatory disease. The incidence of postoperative morbidity was 25 per cent and there was one death. Types of surgical procedures utilized are discussed, and the criteria for hysterectomy with salpingectomy as the operation of choice in the treatment of ruptured tubal pregnancy are presented.
Distal colonic hyperplastic polyps do not predict proximal adenomas in asymptomatic average-risk subjects.

Abstract The significance of distal colonic hyperplastic polyps was investigated in 482 asymptomatic average-risk subjects, aged 50–75 years, in whom fecal occult blood test results were negative and who underwent screening colonoscopy. The incidence of adenomas in the colon proximal to the sigmoid-descending colon junction in subjects with hyperplastic polyps distal to that point was 18% and was similar to the incidence of proximal colonic adenomas in subjects with no distal colonic polyps (15%). The incidence of proximal colonic adenomas in subjects with distal colonic adenomas was 38% and was significantly greater than the incidence found in individuals with no distal colonic polyps or only hyperplastic polyps. Our data do not support distal colonic hyperplastic polyps as markers for proximal colonic adenomas in asymptomatic average-risk subjects.
Perceived and Physiological Indicators of Relaxation: As Different as Mozart and Alice in Chains

The effects of listening to different types of music on perceived and physiological indicators of relaxation were evaluated. Fifty-six undergraduate students, 24 males and 32 females, mean age of 21, were randomly assigned to listen to classical, hard rock, self-selected relaxing music, or no music. Participants' relaxation level, skin temperature, muscle tension and heart rate were evaluated before and after exposure to a music condition. Analyses of variance using baseline measures as covariates indicated that skin temperature decreased for all conditions (p = 0.001) and the classical, self-selected relaxing music and no music groups reported significant increases in feelings of relaxation (p = 0.004). These results partially support the hypothesis that classical and self-selected relaxing music can increase perceptions of relaxation to a greater degree than listening to hard rock music. However, no differences were found between different types of music on physiological indicators of arousal. Implications for using music to reduce stress were discussed.
Metallocenter Biosynthesis & Assembly

Metalloproteins have been characterized intensively for decades, yet only recently has progress been made in characterizing the mechanisms of biological metallocenter biosynthesis and assembly. Here, we describe how cellular synthesis of metal sites makes use of several recurring themes, often with multiple themes combined into a single pathway. In the simplest situation, binding of a metal ion to a biological ligand occurs by reversible thermodynamic control. However, the prevalence of metallocenters deeply buried within macromolecules, the exceedingly low concentrations of free metal ions within cells, and the sophisticated structures of many metal-containing active sites and cofactors provide evidence that alternative and more complex approaches also must exist. In some cases, metallochaperones are used to deliver the metal of interest to an apoprotein. In other cases the target protein undergoes posttranslational modification at the metal-binding site, either prior to or after the metal is bound. Many metallocenters contain additional components that are added along with the metal ion or used to form a preassembled metal-containing cofactor. Scaffolding proteins may be used to provide a framework for construction of the cofactor. Electron transfer reactions involving the metal, an added compound, or the protein ligand can participate in activation. Finally, molecular chaperones that bind to and alter the conformation of the target apoprotein may be utilized. In many cases, the function of the molecular chaperone is coupled to nucleotide triphosphate hydrolysis. Keywords: apoprotein; cofactor; heme; iron–sulfur clusters; metallochaperone; metallocenter; molybdopterin; scaffold proteins
Mate Choice by Both Sexes Maintains Reproductive Isolation in a Species Flock of Pupfish (Cyprinodon spp) in the Bahamas

Female and male mate choices can reinforce reproductive isolation after sympatric speciation. Using a binary choice design, we examine the importance of visual cues in female mate choice in all three sympatric species of pupfish on San Salvador Island. We also examine the importance of olfactory cues in female choice of the hard-shelled invertebrate specialist (Cyprinodon brontotheroides). We examine male mate choice in two of the three species, the scale eater (C. desquamator) and the detritivore (C. variegatus). Females of all three species use visual cues and prefer conspecific males. C. brontotheroides females do not use olfactory cues to discriminate between conspecific and heterospecific males. Males of C. desquamator and C. variegatus also preferentially court conspecific females. Thus, mutual mate choice, where both females and males exhibit mate choice, acts as a strong behavioral pre-mating isolation mechanism in these sympatrically speciated pupfish.
BB creatine kinase and myogenic differentiation. Immunocytochemical identification of a distinct precursor compartment in the chicken skeletal myogenic lineage.

Abstract Antisera specific for the B monomer of creatine kinase (B-CK), the M monomer of creatine kinase (M-CK), and muscle-specific myosin heavy chain (MHC) were used to investigate the biochemical characteristics of individual cells in primary myogenic cultures. Through the use of immunocytochemical techniques, in conjunction with 3H-thy-midine autoradiography, it was determined that (1) all of the terminally differentiated myoblasts contained B-CK in addition to M-CK and MHC, (2) none of the cycling cells contained M-CK or MHC, (3) a fraction (7.5%) of the cycling cells contained B-CK, and (4) the cycling, B-CK positive cells divided once, and only once, and produced two terminally differentiated myoblasts. These results indicate that myogenic precursors in vitro are a phenotypically heterogeneous cell population and that the appearance of B-CK in cycling myogenic cells is a biochemical manifestation of a distinct precursor compartment in the chicken skeletal myogenic lineage.
Widespread occurrence of avian spectrin in nonerythroid cells

We have prepared an antibody against chicken erythrocyte alpha spectrin, using as immunogen protein purified by two-dimensional polyacrylamide gel electrophoresis. One- and two-dimensional immunoautoradiography show that this antiserum reacts only with alpha spectrin in chicken erythrocytes and crossreacts with alpha spectrin in erythrocytes from various mammals. Immunofluorescence reveals that this antiserum reacts with a plasma membrane component in erythrocytes as well as in most nonerythroid avian and mammalian cells. Intense staining is seen at or near the plasma membrane in neurons, lens cells, endothelial and epithelial cells of the gastrointestinal and respiratory tracts, skeletal and cardiac muscle, as well as skeletal myotubes grown in tissue culture. Immunoautoradiography indicates that the crossreactive antigen in these nonerythroid tissues has the same molecular weight and isoelectric point as the chicken erythrocyte antigen. Smooth muscle, tracheal cilia, myelin and mature sperm stain weakly or not at all. These results suggest that spectrin is more extensively distributed than previously recognized, and that the functions of spectrin elucidated for erythrocytes may apply to other cell types as well.
Reform, Regulation, and Pharmaceuticals — The Kefauver–Harris Amendments at 50

In 1962, President Kennedy signed into law the Kefauver–Harris Amendments to the Federal Food, Drug, and Cosmetic Act. Many issues covered by provisions cut from the bill continue to confront those who would ensure access to innovative, safe, efficacious, affordable therapeutics.
Magmas and magma chamber evolution, Troodos ophiolite, Cyprus

The Troodos ophiolite traditionally has been considered to have formed by constructive processes at an oceanic spreading center. New information on the phase layering and cryptic variation in gabbros and ultramafic cumulates overlying tectonized harzburgites, however, does not support the existence of a large, steady-state, frequently replenished, axial magma chamber. Compositional evidence suggests that the Troodos ophiolite was formed by two distinct and chemically unrelated magmatic systems. A stratigraphically lower websteritic and gabbroic cumulate sequence exhibits only one major magma-chamber replenishment, suggesting a nonspreading environment. An upper gabbroic cumulate sequence suggests frequent magma-chamber replenishments, pointing to a relatively fast-spreading environment. This suggests that the alleged Troodos axial magma chamber formed in an off-axis, nonspreading tectonic environment, probably by magmatic underplating of a thin oceanic crust. Spreading-related magmatic activity in the Troodos ophiolite was confined to the upper gabbros and dike complex.
The habitual consumer.

Consumers sometimes act like creatures of habit, automatically repeating past behavior with little regard to current goals and valued outcomes. To explain this phenomenon, we show that habits are a specific form of automaticity in which responses are directly cued by the contexts (e.g., locations, preceding actions) that consistently covaried with past performance. Habits are prepotent responses that are quick to activate in memory over alternatives and that have a slow-to-modify memory trace. In daily life, the tendency to act on habits is compounded by everyday demands, including time pressures, distraction, and self-control depletion. However, habits are not immune to deliberative processes. Habits are learned largely as people pursue goals in daily life, and habits are broken through the strategic deployment of effortful self-control. Also, habits influence the post hoc inferences that people make about their behavior.
Within-day variation of taurine and other nitrogen substances in human milk

Milk samples were collected from seven mothers during their 8th wk of lactation. On the day of collection one breast was completely emptied at 600, 1000, 1400, 1800, and 2200 h. Concentrations of total nitrogen, protein nitrogen, urea nitrogen, and free amino acids (taurine and glutamine plus glutamic acid) were determined. Concentrations of these nitrogen substances in the milk differed significantly among women but were relatively constant during the day. The mean concentrations of these substances per 100 ml of milk were total nitrogen, .189 g; protein nitrogen, .145 g; urea nitrogen, .020 g; taurine 34.9 mumol; glutamine plus glutamic acid, 200.0 mumol.
Core complex model proposed for gneiss dome development during collapse of the Paleoproterozoic Penokean orogen, Minnesota

Gneiss domes preserved throughout the Paleoproterozoic (1870–1820 Ma) Penokean orogenic belt are commonly viewed as collisional features. However, 1700 Ma mica 40Ar/39Ar ages from Archean rocks of the McGrath gneiss dome, Minnesota, are in marked contrast with 1750–1760 Ma mica ages obtained everywhere outside the dome, suggesting the dome may have formed well after compression had ceased. We hypothesize that the bimodal age pattern is a result of crustal excision between Archean basement and Paleoproterozoic cover during extensional collapse of the overthickened orogen. Removal of structural section and progressive unroofing may have led to the development of a domed basement-cover shear zone. In this respect, the McGrath gneiss dome would represent one of the oldest analogues of a metamorphic core complex. Postorogenic collapse of the Penokean orogen was apparently long-lived, with significant pulses occurring at ∼1755 Ma and at ∼1700 Ma The sudden and widespread crustal fusion at 1770–1760 Ma that preceded the proposed collapse suggests that rapid subcrustal lithospheric thinning may have triggered collapse as has been proposed recently for several Phanerozoic collapsed orogens.
Quantitative Analysis of Synthetic Culture Flavor Concentrates by Gas Chromatography

Abstract An internal standard gas chromatographic analysis of synthetic culture flavor concentrates capable of ±10% accuracy for each flavor compound has been developed. The separation of water, acetaldehyde, dimethyl sulfide, acetic acid, diacetyl, propylene glycol, and acetone (the internal standard) was performed with a column packed with 120 to 150 mesh Porapak Q plus a short precolumn packed with 120 to 150 mesh Porapak R. The column was operated isothermally at 155 C with a flame ionization detector.
Effect of chronic mechanical irritation on chemically induced carcinogenesis in the hamster cheek pouch.

Clinical observations have led to the sus­ picion that chronic mechanical irritation contributes to the etiology of oral carci­ noma.1'3 The question of the interrelation of irritation and carcinogenesis has been studied extensively in the skin of experi­ mental animals.4'6 In the limited experi­ mentation dealing with oral mucosa, it has been demonstrated in the mouse and monkey that penetration of the carcino­ gen is increased in areas of ulcera­ tion produced by persistent mechanical trauma.7 In the skin of experimental animals, nonspecific local irritation hast­ ens the transformation of preneoplastic lesions to malignancy.8 The following experiments were con­ ducted to study the effect of chronic me­ chanical irritation on chemically induced carcinoma in the cheek pouch of the hamster.
Service Learning Can Make Occupation-Based Practice a Reality: A Single Case Study

ABSTRACT Service learning is philosophically congruent with the objectives of progressive occupational therapy curricula. This article presents a case-based research study that examined the attributes and outcomes of a service-learning course that included Level I fieldwork. Analysis of the case study identified three themes: (a) the translation of theory to practice, (b) the value of contextual learning, and (c) the gestalt of occupational awareness. Service learning can be considered a pedagogical [2] model that promotes the synthesis of conceptual models to clinical practice. Furthermore, it enables students to develop a professional and personal philosophy of occupation earlier in their careers.
Superconductivity about 120 K in the Tl-Bi-Sr-Ca-Cu-O system

Abstract A number of the samples in the Tl-Bi-Sr-Ca-Cu-O system were prepared by a solid state reaction method and were characterized by X-ray powder diffraction, resistivity and AC magnetic susceptibility measurements. A multi-phased sample with nominal composition TlBiSr 2 Ca 2 Cu 3 O 10 is superconducting with a T c (onset)=119 K and T c ( R =0)= 106 K. X-ray diffraction analysis of the samples shows that the crystal structure of the 120 K superconducting phase is different from that of known Tl-based and Bi-based superconducting compounds. Compared with the lead-doped Bi-Sr-Ca-Cu-O compounds, Tl-Bi-Sr-Ca-Cu-O compounds have an advantage of easier formation.
Effect of Pressure of Atmosphere on Development of Red Clover

SINCE 1932, studies in this laboratory have investigated the effect of partial pressures of various gases on the nitrogen fixation process in inoculated leguminous plants. The results, which throw considerable light on certain properties of the mechanism employed in this biological process, will be reported in detail in a future publication. In connexion with this research, observations which may be of general interest were made on the effect of growing clover under a fairly wide rango of atmospheric pressures. Little work appears to have been reported on this aspect of plant physiology; discussion of the effect of gas pressures in most texts is restricted to the effect of partial pressures of oxygen and carbon dioxide in short-time experiments.
Hair cell bundles: flexoelectric motors of the inner ear.

Microvilli (stereocilia) projecting from the apex of hair cells in the inner ear are actively motile structures that feed energy into the vibration of the inner ear and enhance sensitivity to sound. The biophysical mechanism underlying the hair bundle motor is unknown. In this study, we examined a membrane flexoelectric origin for active movements in stereocilia and conclude that it is likely to be an important contributor to mechanical power output by hair bundles. We formulated a realistic biophysical model of stereocilia incorporating stereocilia dimensions, the known flexoelectric coefficient of lipid membranes, mechanical compliance, and fluid drag. Electrical power enters the stereocilia through displacement sensitive ion channels and, due to the small diameter of stereocilia, is converted to useful mechanical power output by flexoelectricity. This motor augments molecular motors associated with the mechanosensitive apparatus itself that have been described previously. The model reveals stereocilia to be highly efficient and fast flexoelectric motors that capture the energy in the extracellular electro-chemical potential of the inner ear to generate mechanical power output. The power analysis provides an explanation for the correlation between stereocilia height and the tonotopic organization of hearing organs. Further, results suggest that flexoelectricity may be essential to the exquisite sensitivity and frequency selectivity of non-mammalian hearing organs at high auditory frequencies, and may contribute to the “cochlear amplifier” in mammals.
A mammalian guanine-nucleotide-releasing protein enhances function of yeast secretory protein Sec4.

SMALL GTP-binding proteins of the ras superfamily are important for exocytosis from eukaryotic cells1–5. GTP-binding proteins can exist in two different conformations depending on whether they are bound to GDP or GTP, and are thought to function as molecular switches that regulate a variety of cellular processes1,3. The GTP–GDP cycle is controlled by accessory proteins that promote the exchange of bound GDP or the hydrolysis of GTP. The protein Sec4, a member of the Sec4/Yptl/Rab branch of the Ras superfamily, is involved in a late stage of the secretory pathway in yeast6. Here we report the isolation of a mammalian complementary DNA, mss4, encoding a GDP-releasing protein that enhances Sec4 function. The Mss4 protein also stimulates GDP release from Yptl and from the mammalian protein Rab3a, but not from Ras2. Mss4 shows sequence similarity to Dss4, a yeast protein with similar biochemical properties.7