cssi/SciSciGPT-SciSciNet huggingface dataset:
Environmental cadmium as a potential risk factor for thyroid cancer

5593 We measured cadmium (Cd) in normal thyroid tissue of thyroid cancer (TC) patients to determine if Cd is present at levels that might enhance mutagenesis. We hypothesize that environmental Cd contributes to increased risk of TC. Although an increase in TC has been attributed to improved diagnosis (ultrasound vs. palpation), there appears to be a real increase in incidence. In NY State, from1994-2004, there was a near doubling of TC incidence in men and a doubling in women. Cd, a ubiquitous environmental pollutant, has been linked to increased risk of several diseases including lung cancer and, recently, breast cancer (McElroy et al, JNCI 98:869-873, 2006). Among its toxic effects, Cd disrupts thyroid and other endocrine functions and inhibits DNA repair, especially base excision (BER). Cd pollution is increasing worldwide with a ten-fold increase in Cd in mammalian bones in the 20 th century (Jawaroski et al, Sci Total Env 43:103-126, 1985). With an in vivo half-life of 30 years, Cd is known to accumulate in the liver and kidney of non-smoking, non-occupationally exposed individuals and wildlife such as moose and deer. Cd has not been measured in many other tissues in which common cancers arise. Suffolk County, NY (SCNY) has a long history of potato farming, which requires extensive use of phosphate fertilizers that frequently contain Cd. Copper and lead (PB)arsenicals were also used for decades to control potato blight. Both arsenic (As) and Pb may enhance Cd toxicities including inhibition of DNA repair. Although data on Cd levels in SCNY farmland are lacking, soil samples from 10 potato fields in SCNY had 12 to 24 fold more As and 2-4 fold more Pb than a never cultivated field (Sanok et al, Chemosphere 30: 803-806, 1995). Residents of SCNY have high rates of female breast cancer (142.7) and thyroid cancer (16.9 and 7.1 for women and men, respectively) (cases/100,000 persons age-adjusted to the 2000 US population). We measured Cd in normal tissue from thyroids containing a papillary carcinoma from 6 non-occupationally exposed residents of SCNY, 4 women (ages 36, 38, 39, and 70) and 2 men (ages 42 and 61). Each tissue sample was freeze dried, weighed, digested in nitric acid with microwave assisted heating, and analyzed for Cd by Inductively Coupled Plasma-Mass Spectrometry. Cd was detected in all samples ranging from 0.285 to 1.250 ug/g dry weight (average of two samples from each gland). These values correspond to 0.51 to 2.23 umoles/g wet weight, concentrations compatible with inhibition of BER and potentially, other mechanisms of DNA repair. We recommend, therefore, studying the potential role of Cd as a contributor to increased risk of TC in SCNY. Next steps are to measure Cd levels in thyroid tissue from additional TC patients and patients with benign thyroid disease and to determine if residents of SCNY have increased total body burdens of Cd (as measued by urinary Cd) compared to the average US resident as reported in the National Exposure Report issued by the CDC.
Observing Neutral Hydrogen Above Redshift 6: The ``Global'' Perspective

Above redshift 6, the dominant source of neutral hydrogen in the Universe shifts from localized clumps in and around galaxies and filaments to a pervasive, diffuse component of the intergalactic medium (IGM). This transition tracks the global neutral fraction of hydrogen in the IGM and can be studied, in principle, through the redshifted 21 cm hyperfine transition line. During the last half of the reionization epoch, the mean (global) brightness temperature of the redshifted 21 cm emission is proportional to the neutral fraction, but at earlier times (10<z<25), the mean brightness temperature should probe the spin temperature of neutral hydrogen in the IGM. Measuring the (of order 10 mK) mean brightness temperature of the redshifted 21 cm line as a function of frequency (and hence redshift) would chart the early evolution of galaxies through the heating and ionizing of the IGM by their stellar populations. Experiments are already underway to accomplish this task or, at least, provide basic constraints on the evolution of the mean brightness temperature. We provide a brief overview of one of these projects, the Experiment to the Detect the Global EOR Signature (EDGES), and discuss prospects for future results.
144 Gb/s dual-polarization photonic wireless link operating in the V-band

We demonstrate a 144 Gb/s dual-polarization photonic wireless link on a single carrier at 63.5 GHz over a distance of 2.5 meters with a bit-error rate less than 3.8 × 10−3. An overview of system components and architecture is provided, along with results and conclusions.
Novel Measure of Local Impedance Predicts Catheter–Tissue Contact and Lesion Formation

Background: Coupling between the ablation catheter and myocardium is critical to resistively heat tissue with radiofrequency ablation. The objective of this study was to evaluate whether a novel local impedance (LI) measurement on an ablation catheter identifies catheter–tissue coupling and is predictive of lesion formation. Methods and Results: LI was studied in explanted hearts (n=10 swine) and in vivo (n=10; 50–70 kg swine) using an investigational electroanatomic mapping system that measures impedance from an ablation catheter with mini-electrodes incorporated in the distal electrode (Rhythmia and IntellaNav MiFi OI, Boston Scientific). Explanted tissue was placed in a warmed (37 °C) saline bath mounted on a scale, and LI was measured 15 mm away from tissue to 5 mm of catheter–tissue compression at multiple catheter angles. Lesions were created with 31 and 50 W for 5 to 45 seconds (n=90). During in vivo evaluation of LI, measurements of myocardium (n=90) and blood pool (n=30) were guided by intracardiac ultrasound while operators were blinded to LI data. Lesions were created with 31 and 50 W for 45 seconds in the ventricles (n=72). LI of myocardium (119.7 Ω) was significantly greater than that of blood pool (67.6 Ω; P R 2 =0.75 versus R 2 =0.54) and generator impedance drop ( R 2 =0.82 versus R 2 =0.58). Steam pops displayed a significantly higher starting LI and larger ΔLI compared with successful radiofrequency applications ( P Conclusions: LI recorded from miniature electrodes provides a valuable measure of catheter–tissue coupling, and ΔLI is predictive of lesion formation during radiofrequency ablation.
The Worth Four Dot Test: Is it Really “Worthless”?

The Worth 4 Dot Test was introduced by Claude Worth in 1903 as a test measuring binocularity. Hardy, in 1937, incorporated the lights of Worth into a hand-held flashlight. Further modifications wer...
Introduction: Popular Paperbacks and the Transformation of American Liberalism

This introduction establishes the cultural context of the period under review (1972–2017). It then articulates the urgent need for a study of mass-market fiction as a way to address the transformation of liberalism in the United States. With an unofficial tally of over 1.2 billion copies sold (and counting), the novels considered in this book consistently perch atop all-time bestselling lists. One might reasonably assume that readers choose these specific texts due to their clarity, accessibility, and coherence. These traits remain useful indices of intelligibility. As this introduction seeks to illustrate, popular paperbacks serve as ideal sites for tracking the readability—or incongruity—of political sentiments in the contemporary United States.
Holographic Measurements of Bubble Size and Velocity in a Three-Phase System

An off-axis holographic technique has been developed for the direct determination of bubble size distributions and velocities within a three-phase fluidized bed system. Such a system consists of gas and liquid phases flowing cocurrently upward through a fluidized solid bed. By carefully selecting the liquid to match the refractive index of the solid phase it is possible optically to view the bubbles as they rise through the column. With the aid of a high-energy pulsed laser, a three-dimensional image of the bubbles can be constructed in the form of a hologram containing the size and location of each bubble within the viewing volume. Reconstructed holograms are viewed by a video camera and measurements are made with a digital electronic circuit which locates coordinates on the video screen. This method is especially useful for nonspherical bubbles, which are difficult to measure with intrusive probes or narrow beam-scattering techniques.
Response to Torin Alter

My thanks to Prof. Alter for his careful, kind, and cautionary commentary. I shall try to live up to the standard he has set.
Understanding and Exploiting Bacterial Outer Membrane Vesicles

The bacterial outer surface defines the interface between an organism and its environment and thus plays an important role in facilitating interactions between the two. The structures comprising the cellular envelope have received considerable research interest, but an emerging area aims to understand how and why Gram negative bacteria actively shed fragments of their outer membrane into the surrounding milieu. This phenomenon has been observed in nearly all Gram-negative organisms studied and has even been described as a dedicated secretion system. In this communication, we describe the history, structure, composition, functions and mechanism of formation of outer membrane vesicles. In addition, we discuss the promise of exploiting OMVs for pharmaceutical purposes and the early successes that have been seen with OMV vaccines.
A finite-element simulation of pulsatile flow in flexible tubes

The finite-element model for pulsatile flow in a flexible unob- stiTucted tuoe ^aescrioed zii rart—^ j-S cxpciuueu Lo j-ticxude a stenosis. ine applicability of the model is checked by comparing predicted flow and pressure waveforms with corresponding experimental results obtained from in vitro measurements on a mechanical system. The laboratory model in­ cludes a pulsating pump, a latex tube partially obstructed by a hollowed, cylindrical rigid plug, and a peripheral resistance. Good agreement is found between predicted and experimental flow and pressure waveforms.
Ebstein’s Anomaly of the Tricuspid Valve: A Natural Laboratory for Re-Entrant Tachycardias

Ebstein's anomaly of the tricuspid valve is a relatively rare form of congenital heart disease that has long been a challenge to electrophysiologists and cardiac surgeons. In addition to the hemodynamic burden of the actual valve defect, Ebstein's patients must also contend with an extraordinarily high incidence of tachyarrhythmias, most of which can be attributed to accessory atrioventricular pathways (APs) located along the posterior and septal border of the tricuspid valve where the valve leaflets are most abnormal. It is the only congenital heart defect with such a dramatic predisposition toward APs. Although it is logical to postulate a link between the anatomic deformity and the conduction abnormality, the exact nature of this link is still not fully understood and remains a fertile area for investigation that might shed light on abnormal conduction pathways in many other forms of heart disease. Furthermore, for reasons that are only now being fully appreciated, successful catheter ablation of APs in this setting is frequently more challenging than would be expected in a structurally normal heart. This review will explore the gross and microscopic anatomy of Ebstein's anomaly with attention to features that could be important to both arrhythmogenesis and ablation therapy in this unique population.
Chapter 8 – Batteries, Kirchhoff's Rules, and Complex Circuits

The concept of an electric circuit did not exist when electrostatic was the only type of electromotive force (emf). This chapter reviews the properties of the battery as a combination of individual voltaic cells. Most circuits cannot be analyzed solely in terms of series and parallel resistors with a battery here or there. To deal with bridge circuits, or systems with multiple arms containing sources of chemical emf, or systems with both resistors and capacitors, one must use the Kirchhoff's rules, first stated around 1850. This systematic approach to circuits uses solely the macroscopic properties of circuits: resistances, capacitances, and emfs (both electrostatic and non-electrostatic). Kirchhoff's rules are a set of two rules that describe any sort of circuit with connecting wires of zero resistance, resistors R, capacitors C, and non-electrostatic sources of emf ɛ. However, before they can be applied to any circuit, the currents and voltages for that circuit must be defined precisely. Instead of perfectly straight wires, real circuits have sloppily placed wires that run over and under one another. It can be a difficult task to disentangle and trace their connections. But these connections are precisely what are needed to apply Kirchhoff's rules.
A Comparison of Sensor Placement for Estimating Trunk Postures in Manual Material Handling

Wearable measurement systems have become increasingly more popular in estimating exposures to awkward trunk postures. One limitation in using these systems is the lack of research confirming the optimal placement of the sensors for accurate quantification of trunk postures. The present study explored the effect of sensor placement in estimating trunk postures using XsensTM (Xsens Technologies, NL) during simulated manual material handling tasks in the laboratory. The researchers found a single IMU on the sternum estimated summary measures and percent time in trunk posture categories similarly to the reference method placement.
Design of a Microgrid Transition Controller II: System Recovery Under Abnormal Conditions

This paper presents a microgrid transition controller for managing emergency operation when the microgrid experiences a system blackout caused by an internal or external fault. The developed transition controller consists of various application function blocks, including normal operation, emergency operation, and coordination between them. The developed microgrid transition controller is validated by a sample microgrid, and two test cases are investigated: islanded black start and grid-connected black start. The simulation results demonstrate the feasibility and effectiveness of the proposed microgrid transition controller for handling emergency operation and transitioning to normal operation.
Model AI assignments 2012

The Model AI Assignments session seeks to gather and disseminate the best assignment designs of the Artificial Intelligence (AI) Education community. Recognizing that assignments form the core of student learning experience, we here present abstracts of three AI assignments from the 2012 session that are easily adoptable, playfully engaging, and flexible for a variety of instructor needs. Assignment specifications and supporting resources may be found at http://modelai.gettysburg.edu.
The Value of Anthropometric Measures in Nutrition and Metabolism: Comment on Anthropometrically Predicted Visceral Adipose Tissue and Blood-Based Biomarkers: A Cross-Sectional Analysis.

Visceral adipose tissue (VAT)—fat stored deep in the abdominal cavity that surrounds vital organs—is associated with a variety of chronic health conditions. Computed tomography and magnetic resonan...
Wrinkles in Time: Detecting Internet-wide Events via NTP

Understanding the nature and characteristics of Internet events such as route changes and outages can serve as the starting point for improvements in network configurations, management and monitoring practices. However, the scale, diversity, and dynamics of network infrastructure makes event detection and analysis challenging. In this paper, we describe a new approach to Internet event measurement, identification and analysis that provides a broad and detailed perspective without the need for new or dedicated infrastructure or additional network traffic. Our approach is based on analyzing data that is readily available from Network Time Protocol (NTP) servers. NTP is one of the few on-by-default services on clients, thus NTP servers have a broad perspective on Internet behavior. We develop a tool for analyzing NTP traces called Tezzeract, which applies Robust Principal Components Analysis to detect Internet events. We demonstrate Tezzeract’s efficacy by conducting controlled experiments and by applying it to data collected over a period of 3 months from 19 NTP servers. We also compare and contrast Tezzeract’s perspective with reported outages and events identified through active probing. We find that while there is commonality across methods, NTP-based monitoring provides a unique perspective that complements prior methods.
Life events, poverty, and car ownership in the United States: A mobility biography approach

What causes families to buy or give up a car in the U.S.? Following the mobility biography approach, we use a nationally representative panel data set, the Panel Study of Income Dynamics (PSID), to examine the role of life events and changes in the built environment and compare the effect that these events have on changes in car ownership. We find that coupling, graduating from college, and the birth or adoption of a child all are associated with increases in car ownership, while breaking up is associated with decreases in car ownership. Moving to or away from transit-rich, dense, walkable neighborhoods matters but only when one moves to a very different type of neighborhood. We also find that life events have a stronger association with gaining a car for non-poor families than for families in poverty. Life events are windows of opportunity when families reevaluate their travel patterns. Interventions at these critical junctures could be an expedient way to decrease car ownership and its attendant problems, especially when combined with improving alternatives to the automobile.
Correlation of PROMIS Physical Function, Pain Interference, and Depression in Pediatric and Adolescent Patients in the Ambulatory Sports Medicine Clinic.

Background:Recently, interest has increased in incorporating the National Institutes of Health Patient-Reported Outcomes Measurement Information System (PROMIS) outcomes into clinical and research ...
Feasibility of Non-Invasive Screening for Coronary Allograft Vasculopathy with Positron Emission Tomography Derived Myocardial Blood Flow Assessment

Background Recent studies have shown promising data supporting the use of positron emission tomography (PET) in place of the current invasive gold standard, coronary angiography to screen for coronary allograft vasculopathy (CAV). Hypothesis We hypothesize that PET can functionally assess flow using myocardial blood flow (MBF) which correlates with CAV and can portend poor outcomes. Methods We retrospectively identified all heart transplant recipients who had regadenoson rubidium-82 PET rest-stress tests and coronary angiography at our institution between November 2012 and March 2019. CAV grade was based on ISHLT criteria according to Figure 1 which is adapted from researchers at Brigham and Women's Hospital. A cutoff of MBF Results We collected data from 31 patients with 44 PET studies. Of this population, 28 patients had coronary angiography performed which resulted in 37 total PET studies for comparison. Of the total collection of PET studies, 36% had CAV 0 (n=16), 36% had CAV 1 (n=16), and 28% had CAV 2-3 (n=12). When analyzing the subset who had both PET and angiography (n=31), of those with grade 0 CAV on PET, all patients also had no angiographic CAV (n=13). Of those with PET grade 2 or 3 CAV, 2 patients had no angiographic CAV and 6 patients had corresponding moderate-severe CAV angiographically. Conclusion PET appears to be a good screening modality for CAV, as all of those with severe CAV angiographically had at least grade 1 CAV on PET. PET should be strongly considered as the primary method of CAV screening to avoid the risks of invasive angiography in a particularly delicate population of patients.
Use of e-Cigarettes and Development of Respiratory Conditions in Women of Childbearing Age.

Objective Women of childbearing age are encouraged not to smoke because of well-documented adverse health outcomes. This study examines the association between e-cigarette use and respiratory conditions (asthma and chronic obstructive pulmonary disease [COPD]) among women of childbearing age. Methods The study used data from the Behavioral Risk Factor Surveillance System 2016-2017. The sample consisted of 131,965 women of childbearing age (18-44 years old). The main independent variable was smoking status and the primary outcomes were self-reported respiratory conditions such as asthma and COPD. Data were analyzed using descriptive statistics and multivariate logistic regression to assess the effects of e-cigarettes on asthma and COPD. Results In this sample of childbearing-age women, 2.79% were current e-cigarettes users with or without a history of combustible cigarette smoking and 3.02% were current dual users. Compared with nonsmokers, current e-cigarette users without a history of combustible cigarette smoking were associated with 74% higher odds of having asthma (adjusted odds ratio [AOR] 1.74, 95% confidence interval [CI] 1.29-2.35), whereas results were not significant for COPD. The odds of having COPD, however, were 3 times higher (AOR 3.28, 95% CI 2.62-4.12) for current e-cigarette users with a history of cigarette smoking, whereas current dual users showed 5 times higher odds (AOR 5.07, 95% CI 3.91-6.56) of COPD compared with nonsmokers. Conclusion Policies related to e-cigarettes need to be reevaluated and clearly communicated to improve prevention efforts for women of childbearing age.
March On - Diversity in the Face of Adversity.

March On — Diversity in the Face of Adversity When a virtual White Coats for Black Lives “march” was disrupted by racist intruders, the organizers persevered. The diverse perspectives and collectiv...
Rare cause of unilateral upper limb weakness in a young adolescent

Slowly progressing unilateral upper limb weakness in a previously healthy child can occur due to number of causes which requires a thorough history, physical examination followed by radiological examination, electromyography and so on. Among the various aetiologies, a rare condition such as Hirayama disease is one of the differentials to be considered. There has been a wealth of literature reported on this disease and our case is a learning lesson for all paediatricians to be aware of Hirayama disease and its current concepts.
High-dimensional analysis defines multicytokine T-cell subsets and supports a role for IL-21 in atopic dermatitis

BACKGROUND Flow cytometry is a well-accepted approach for immune profiling; however, its value is restricted by the limited number of markers that can be analyzed simultaneously. Mass cytometry/CyTOF offers broad-scale immune characterization integrating large number of parameters. While partial blood phenotyping was reported in atopic dermatitis (AD), patients' comprehensive profiling, critical for leveraging new targeted treatments, is not available. IL-21 may be involved in inflammatory skin diseases but its role in AD is not well established. METHODS We studied T-cell polarization in the blood of 20 moderate-to-severe AD and 15 controls. Using CyTOF and an unsupervised analysis, we measured the frequencies and mean metal intensities of activated polar CD4+ /CD8+ T-cell subsets. Immunohistochemistry, immunofluorescence, and qRT-PCR were used to analyze skin samples. RESULTS Examining 24 surface, intracellular markers, and transcription factors, we identified six CD4+ and five CD8+ T-cell metaclusters. A CD4+ skin-homing IL-13+ monocytokine and a novel IL-13+ IL-21+ multicytokine metaclusters were increased in AD vs. controls (p < .01). While IL-13 signature characterized both clusters, levels were significantly higher in the IL-21+ group. Both clusters correlated with AD severity (r = 0.49, p = .029). Manual gating corroborated these results and identified additional multicytokine subsets in AD. Immunohistochemistry and immunofluorescence, validated by mRNA expression, displayed significantly increasedIL-21 counts and colocalization with IL-13/IL-4R in AD skin. CONCLUSION A multicytokine signature characterizes moderate-to-severe AD, possibly explaining partial therapeutic responses to one cytokine targeting, particularly in severe patients. Prominent IL-21 signature in blood and skin hints for a potential pathogenic role of IL-21 in AD.
Shark fisheries during the second millennium BC in Gramalote, north coast of Peru

This paper stresses the importance of shark fisheries at the site of Gramalote, an early Initial Period (1500–1200/1100 cal BC) fishing settlement, which has yielded the largest amount of shark rem...
DESAFIOS E POTENCIALIDADES DA INTERCULTURALIDADE: A INTERNACIONALIZAÇÃO DAS INSTITUIÇÕES DE ENSINO SUPERIOR

O objetivo do artigo e refletir sobre os conceitos da internacionalizacao e da interculturalidade, tracando os desafios interculturais emergentes por conta da internacionalizacao em uma universidade comunitaria da regiao Sul do Brasil, na perspectiva do gestor responsavel pela internacionalizacao. Trata-se de um estudo de caso, no qual foi desenvolvida uma entrevista semiestruturada com o assessor de assuntos internacionais da instituicao. Concluimos que a interculturalidade se apresenta desde a relacao e concepcoes de internacionalizacao propostas pelas instituicoes de ensino superior do hemisferio norte, visto que elas tentam impor suas formas e modelos de internacionalizacao. As relacoes interpessoais necessitam de mediacao do assessor de assuntos internacionais para que os alunos compreendam a realidade em que se inserem.
Risk Analysis for Ground Failure by Liquefaction

A risk analysis has been developed for studying the likelihood of earthquake-induced ground failure by liquefaction. In this analysis, a new empirical method for evaluating the liquefaction potential at a site is employed. The method is based on interpretation of case histories in terms of earthquake magnitude and hypocentral distance. Employing this method, the probability of liquefaction at a site, as a function of earthquake magnitude and hypocentral distance, is first evaluated and then integrated over all magnitudes and distances of interest to obtain the total overall annual probability of liquefaction at the site. An example study is included in which the overall risk of liquefaction at a site is evaluated.
Compliance Analysis and Tool Holder Design for Grinding with Robots

Grinding robots must hold and guide a grinding tool in the face of large vibratory loads. This paper presents an optimal compliance design for grinding tool suspension systems, with the objective of reducing vibrations and maximizing material removal rate. First, the endpoint compliance matrix of the main robot is utilized to determines the optimal workpiece position and orientation. Then a method for determining the optimal end-effector compliance matrix for a given workpiece position and orientation is presented.
Current progress in the study of global biogeochemical cycles

Abstract Aspects of global cycles of carbon, nitrogen and sulfur are reviewed. New work defining carbon source and sink strengths in oceans, northern forests and tundra, and wetlands is discussed. Effects of CO 2 and N fertilization on the carbon cycle may be large but are currently ill-defined. Recent changes in rates of increase of CO 2 , CH 4 and CO in the atmosphere are probably related to volcanic eruptions. The global nitrogen cycle is grossly disturbed by human activity. Land use change and fertilizer use in the tropics may be major sources of N 2 O. Ammonia merits further study as a regional pollutant and because of its role in tropospheric aerosol formation. Sulfate aerosols are now recognized as having significant negative forcing on climate. Whilst the direct (radiative scattering) effect of aerosols is well-understood, the indirect effect (altering could properties) is very uncertain, and inclusion of aerosol effects in climate models is limited by lack of data on aerosol regional distributions. In the future, industrial growth in developing countries will alter the amounts and global distribution of greenhouse gases and aerosols, and the change and distribution of aerosols will have particularly important implications for future regional climate change.
Composition-control of magnetron-sputter-deposited (BaxSr1−x)Ti1+yO3+z thin films for voltage tunable devices

Precise control of composition and microstructure is critical for the production of (BaxSr1−x)Ti1+yO3+z (BST) dielectric thin films with the large dependence of permittivity on electric field, low losses, and high electrical breakdown fields that are required for successful integration of BST into tunable high-frequency devices. Here, we present results on composition-microstructure-electrical property relationships for polycrystalline BST films produced by magnetron-sputter deposition, that are appropriate for microwave and millimeter-wave applications such as varactors and frequency triplers. Films with controlled compositions were grown from a stoichiometric Ba0.5Sr0.5TiO3 target by control of the background processing gas pressure. It was determined that the (Ba+Sr)/Ti ratios of these BST films could be adjusted from 0.73 to 0.98 by changing the total (Ar+O2) process pressure, while the O2/Ar ratio did not strongly affect the metal ion composition. Film crystalline structure and dielectric properties ...
1989 Alice Hamilton lecture: Lead and human health: Background and recent findings

This paper, prepared in tribute to Dr. Alice Hamilton on her 120th birthday, reviews her pioneering studies of occupational lead poisoning and its control, her largely unheeded warnings about the possible consequences of widespread lead exposure to the general public through the use of leaded fuel, and the results of recent studies of human exposure to and health effects of lead in the general environment. Evidence is presented for dose-related non-threshold effects for children with blood lead concentrations below 25 micrograms/dl for a variety of effects including verbal IQ; mental development; physical size; and age at physical milestones such as first steps, hearing thresholds, and postural sway. For adults, various studies have produced associations between blood pressure and blood lead concentrations below 35 micrograms/dl, suggesting possible effects on cardiovascular health. While the biological mechanisms responsible for these effects remain poorly understood, recent and current efforts to reduce exposure to lead by the virtual elimination of lead in gasoline and food packaging show that we have learned one of Dr. Hamilton's important lessons, i.e., that the most effective means of reducing excessive exposures are through control of the environmental sources.
A positive patterning advantage with complex but not simple patterning: A cue constellation approach

Determinants of a positive patterning advantage (that is, an advantage for positive patterning over negative patterning) in human causal reasoning were examined in an experiment that compared simple patterning discriminations (A, B vs. AB) to complex patterning discriminations (AB, BC, AC vs. ABC). As predicted by a cue constellation analysis of complex discriminations, a positive patterning advantage was found with complex patterning but not with simple patterning discriminations. This result may explain why some recent studies have found a positive patterning advantage where earlier studies had failed to find one. The interaction of patterning complexity with the positive patterning advantage appears to pose problems for rule-based accounts of patterning. The results support the view that associative theories of human causal reasoning are more easily distinguished from rule-based approaches when applied to conditions that make simple rules difficult to identify or implement.
Initial Results of Argon Purification in the Liquid State

Argon, deliberately contaminated with air, has been purified in the liquid state by the use of molecular sieves to a level better than one part per billion (02 equivalent). This argon was maintained for a period exceeding 10 days with no detectable increase in impurity concentration. Twelve hours after transfer to a test detector, an attenuation length of 170 cm in a drift field of 1 kV/cm was measured for ionization electrons. These results are essential steps toward the realization of large liquid argon time projection chambers.
Effect of Ether Extract of the Thymus and Pancreas on Synthesis of Acetylcholine.

Summary1. The effects of ether extracts of thymus, pancreas, lymph gland, thyroid, salivary gland, lung, and subcutaneous fat on the synthesis of acetylcholine were investigated. 2. Extracts of thymus and of pancreas significantly decreased the synthesis of acetylcholine in vitro while the other extracts had no demonstrable effect on this process. 3. Less acetylcholine was synthesized in the presence of serum from animals injected with the extract of thymus and pancreas than in the presence of serum from non-injected animals or animals injected with extracts of lungs. 4. The extracts of the thymus and pancreas contained neither nucleoproteins nor their decomposition products in an amount demonstrable with ultraviolet spectrography.
Metabolic correction of fucosidosis fibroblasts by human α‐L‐fucosidase

Human alpha-L-fucosidase, purified from placenta, was taken up from the culture medium by skin fibroblasts from patients with fucosidosis (alpha-L-fucosidase deficiency). The rate of uptake was low (uptake coefficient = 6 X 10(-4) ml.mg-1.h-1). Intracellular alpha-L-fucosidase activity was directly proportional to enzyme in the medium up to an activity of at least 40 nmoles/min/ml. No evidence for saturation of specific cell-surface receptors was seen. However, uptake was reduced by 75% by 1 mM mannose-6-phosphate and by 50% by 1mM glucose-6-phosphate, suggesting that uptake may be mediated by a receptor recognising a phosphorylated sugar or an analagous compound. Enzyme taken up by the cells was most active in subcellular fractions enriched with lysosomes and had an isozyme pattern, by isoelectric focusing, identical to that of the original enzyme preparation. Fucosidosis fibroblasts were shown to accumulate low molecular-weight, fucose-containing compounds to a level several times greater than control cells. This stored material was eluted from Sephadex G-25 as an asymmetrical peak with an elution volume of approximately twice the void volume of the column. Addition of placental alpha-L-fucosidase to the culture medium of fucosidosis fibroblasts prevented excessive accumulation of fucose-containing material and accelerated the breakdown of material accumulated prior to enzyme uptake.
Effects of chronic anemic hypoxia on skeletal muscle mass, protein degradation, and oxygen utilization

We evaluated the effects of 6 months of anemic hypoxia (mean hemoglobin 7.0 ± .9 g/dL) in six dogs on muscle mass, protein degradation, and oxidative performance at rest and during exercise. Anemia reduced systemic oxygen delivery (DO2) by 56% relative to controls, but oxygen uptake (VO2) Was unchanged and similar to controls. Anemic animals demonstrated significant weight loss (16% relative to controls) and a reduction in skeletal muscle mass (84% of control, P < .05). This reduction in muscle mass was due to decreased muscle synthesis, as evidenced by reduction of the ratio of urinary 3-methylhistidine to creatinine, an index of skeletal muscle protein degradation. In resting skeletal muscle, VO2 was independent of DO2. During stimulated contraction, evidence for both supply dependence and diffusion limitation of VO2 was observed. Thus, resting systemic and skeletal muscle VO2 is maintained during chronic anemic hypoxia by increasing O2 extraction, and VO2 is independent of DO2. However, supply dependence and diffusion limitation of VO2, together with reduced skeletal muscle mass, may limit oxidative performance of exercising skeletal muscle.
The National Politics of Formula Allocation Some Evidence for a Rural Bias

Distribution formulas have made Congress' bias less obvious, but it has been, nevertheless, real.
Response Frequency as a Function of Remote Associational Ability, Type of Verbal Stimulus, and Serial Position of Response.

Summary This study investigated predictions from Mednick's remote associates theory as to unusualness of response in a word association task as a function of remote associational ability (high or low scores on the RAT), the nature of the verbal stimulus (flat or steep hierarchy words), and the serial position of the response. Ss were Ohio high school students. Although high RAT scorers gave significantly less unusual responses overall than did low RAT scorers, results were interpreted as generally supportive of the theory. Low RAT scorers moved more rapidly to less frequent responses than did high RAT scorers, later responses were more infrequent than earlier responses in the sample tested, and while word-type did not in itself determine unusualness of response, it did interact with the other variables in a manner consistent with the theory.
Interaction of Propagating Radicals with Copper(I) and Copper(II) Species

The effects of copper(I) and copper(II) metal centers on the atom transfer radical polymerization (ATRP) of styrene and methyl acrylate were investigated. The free-radical polymerizations were initiated by AIBN in the presence of copper(I) and copper(II) complexes. For methyl acrylate, the rate of the polymerization was reduced in the presence of CuIBr/dNbpy and CuIOTf/dTbpy but was unaffected by the presence of CuII(OTf)2/dTbpy. For styrene, under conditions which yield relatively low molecular weight polymer (16 000), no effect was observed in the presence of CuII(OTf)2/dNbpy; however, under conditions which yield high molecular weight polystyrene (50 000-100 000), the polymerization was limited in the molecular weight attainable and stopped at partial conversion. No effect was observed for the free-radical polymerization of styrene in the presence of copper(I) complexes. These results indicate that control in ATRP does not originate in interactions of growing radicals with copper complexes but in the reversible halogen atom transfer.
Central equatorial Pacific zonal currents. II: The seasonal cycle and the boreal spring surface eastward surge

The seasonally averaged zonal momentum equation tendencies at 140W are studied in a high-resolution primitive equation ocean general circulation model simulation of the tropical Pacific. The model experiment, forced by climatological monthly average wind-stress, reproduces well the observed boreal springtime eastward surge of the normally westward surface flow, as well as many features of the acceleration and deceleration between the surface and 200 m between January and October. We present each of the zonal momentum equation tendency terms for the depth range 0-160 m, but our discussion focuses on the behavior of the boreal springtime near-surface flow, perhaps the most distinctive feature of the seasonal cycle. The eastward surface surge in boreal spring depends crucially on the springtime weakening of the otherwise westward tendency from tropical instability waves (TIWs). The TIW effects, together with the eastward tendency from the seasonal weakening of the easterly wind-stress, drive the eastward surface current surge. Although the negative viscosity' effect of the TIWs is small in the annual mean, as we have previously shown, its seasonal variation is necessary to the surface flow reversal and eastward surge in this model. A series of experiments, each with weaker TIWs than its predecessor, shows a progressive weakening and eventual absence of springtime eastward surface flow, supporting the above analysis. The seasonal zonal velocity accelerations and decelerations are small compared with the terms in the zonal momentum equation; these terms must be known to an accuracy of at least 10 cm s -1 month -1 (2-5% of the largest terms) if a meaningful budget is to be obtained. This is a strong constraint that must be planned for in future observational studies. We find that nonlinear terms are O(1) in the vertically-integrated balance as well as the local balance, in contrast with some recent observational estimates. Extrapolated velocity errors, neglected terms, data processing assumptions, and crude finite-differencing in the observational studies may account for the differences, as appeared to be the case in the annual mean balances. The model dynamical balances cannot be reproduced if the methods used to analyze observational data are applied to the model output fields. Very near-surface currents must be measured rather than extrapolated if the ocean shear is similar to that of the model flows.
Sensitivity of forelimb swing phase inverse dynamics to inertial parameter errors

Summary Estimations of segmental inertial parameters are required for true inverse dynamics calculations during the swing phase of locomotion. This study attempts to quantify the effect of inertial parameter errors on inverse dynamic solutions. Swing phase forelimb net joint moments and powers at the trot (mean ± s.d 3.03 ± 0.16 m/s) were calculated with sagittal plane kinematic data from 5 Dutch Warmbloods using inertial parameters based on published regression equations for the breed. Significant peaks in the net moment and power curves for each forelimb joint were identified and measured. Net joint moments and powers were then recalculated after varying the segment mass, location of the segment centre of mass and the mass moment of inertia separately for each of the limb segments. Peak values for the net joint moments and joint powers were determined after each variation, and the percent change in peak value per percent change in inertial parameter was calculated. Segment mass was the most influential parameter, followed by location of the centre of mass. Changes in the mass moment of inertia showed little effect on peak values. The most influential single inertial parameter was the mass of the hoof segment with a mean ± s.d effect 0.74 ± 0.22 and 0.69 ± 0.18 percent peak change per percent parameter change on net joint moments and powers, respectively, across all joints. The results demonstrate the need for an accurate approximation of segment masses during the swing phase, especially the hoof, and the need to account for any additional masses in the model, such as shoes.
Qualitative similarities between the behavior of coupled oscillators and circadian rhythms

This paper summarizes in a nonmathematical way the major properties of coupled oscillators which relate to circadian rhythms. For certain values of the coupling strength it is far easier to maintain synchrony than to achieve it among the various interacting units. This property not only simulates the free run period lability but also the effects of critical pulses.
Type VI Secretion: not just for pathogenesis anymore

Type VI secretion systems (T6SS) have been studied primarily in the context of pathogenic bacteria-host interactions. Recent data suggest, however, that these versatile secretion systems may also function to promote commensal or mutualistic relationships between bacteria and eukaryotes or to mediate cooperative or competitive interactions between bacteria.
IV.—On Mr. Helland's Theory of the Formation of Cirques

In the Quarterly Journal of the Geological Society (vol. xxxiii. p. 142) is an important paper by Mr. Helland, on Fjords, Lakes, and Cirques in Norway and Greenland. In this he notices a theory of mine on the formation of cirques which was published in the same journal (vol. xxvii. p. 312). As I mentioned in a note attached to his paper, he somewhat misunderstands me, supposing apparently that I describe only cirques of a small size,—the fact being, that, so far as I know, the Alpine cirques are quite commensurate with those of Norway. This, however, is of slight importance. My present purpose is to give reasons why, after further observations in the Alps and Pyrenees, and even in the British Isles, I still prefer the explanation then advanced, that the cirques are mainly produced by the combined erosive action of streamlets, to the one given by Mr. Helland, that a cirque is a result of glacial action.
The Necessity for Steroid Induction or Long-Term Maintenance After Liver Transplantation: The Argument Against

HE question to be debated is whether our traditional reliance on steroids is relevant in the 1990s, given the new immunosuppressive modalities now available to us. The immunosuppressive properties of steroids are certainly of historic importance in the success of solid organ transplantation. As early as 1951, the efficacy of steroid immunosuppression in prolonging survival of rabbit skin homografts was demonstrated, 1 and the early success of human renal allografts was also clearly dependent on steroid therapy. However, in the modern era of improved immunosuppressive choices, it is now necessary to critically assess the balance between the immunosuppressive benefits of steroid therapy and their side effects, many of which carry significant morbidity, particularly with longterm use. Steroids exert their immunosuppressive effect by inhibition of cytokine expression. 2 This is particularly important in the direct blockade of IL1 and IL6 release from antigen presenting cells, which prevents optimal T helper cell stimulation. Steroids have also been shown to inhibit IL2, IL3, TNFa, and interferon-g, a mechanism which requires costimulation and affects activated T cells. Counterbalancing these beneficial immunosuppressive properties are the well described adverse effects of steroids, the most important of which are osteoporosis, hypertension, glucose intolerance, hyperlipidemia, obesity, and growth stunting. 3 The morbidity associated with
Elastic interaction of extended screw dislocations with 〈110〉 misfit defects in anisotropic F.C.C. crystals

Elastic interaction between extended screw dislocations and defects of the 〈110〉 type is studied by computing the energy–distance and the force–distance profiles for several metals using anisotropic elasticity theory. It is shown that anisotropy has a significant effect on the magnitudes of interaction energy and interaction force, and on the shape of the energy–distance and force–distance curves. From the results obtained, the maximum interaction energy between dislocations and divacancies of various orientation in copper is also calculated. Elastische Wechselwirkungen zwischen ausgedehnten Schraubenversetzungen und Defekten vom 〈110〉-Typ werden mittels Berechnung des Energie-Distanz- und der Kraft-Distanzprofile fur einige Metalle mit der anisotropen Elastizitatstheorie untersucht. Es wird gezeigt, das die Anisotropie einen betrachtlichen Einflus auf die Grose der Wechselwirkungsenergie und der Wechselwirkungskraft und auf die Form der Energie–Distanz- und Kraft–Distanz-Kurven haf. Aus den erhaltenen Ergebnissen wird auch die maximale Wechselwirkungsenergie zwischen Versetzungen und Doppelleerstellen verschiedener Orientierung in Kupfer berechnet.
Building the Centriole

Centrioles are conserved microtubule-based organelles that lie at the core of the animal centrosome and play a crucial role in nucleating the formation of cilia and flagella in most eukaryotes. Centrioles have a complex ultrastructure with ninefold symmetry and a well-defined length. This structure is assembled from a host of proteins, including a variety of disease gene products. Over a century after the discovery of centrioles, the mechanisms underlying the assembly of these fascinating organelles, in particular the establishment of ninefold symmetry and the control of centriole length, are now starting to be uncovered.