cssi/SciSciGPT-SciSciNet huggingface dataset:
A Test of Exogeneity Without Instrumental Variables in Models With Bunching

This paper presents a test of the exogeneity of a single explanatory variable in a multivariate model. It does not require the exogeneity of the other regressors or the existence of instrumental variables. The fundamental maintained assumption is that the model must be continuous in the explanatory variable of interest. This test has power when unobservable confounders are discontinuous with respect to the explanatory variable of interest, and it is particularly suitable for applications in which that variable has bunching points. An application of the test to the problem of estimating the effects of maternal smoking in birth weight shows evidence of remaining endogeneity, even after controlling for the most complete covariate specification in the literature.
Imprint of the Late Palaeozoic Ice Age on stratigraphic and carbon isotopic patterns in marine carbonates of the Orogrande Basin, New Mexico, USA

The Permian records one of the most extreme climate transitions of the Phanerozoic, yet the climatic and environmental dynamics of this interval and their effects on neritic carbonate systems remain poorly constrained. New stratigraphic and carbon isotope records from uppermost Pennsylvanian to Lower Permian strata of the Orogrande Basin in south-central New Mexico, USA, provide fresh insights into the response of palaeotropical carbonate systems to the growth and demise of ice sheets on Gondwana. The earliest Permian acme of glaciation is recorded in the Orogrande Basin as a series of subaerial exposure surfaces marked by highly variable δ13C values that tend toward values as low as −6‰. These stratigraphic and isotopic patterns are interpreted to reflect the retreat of the sea from the basin during glacial expansion. Younger (Lower Sakmarian to Kungurian) strata, deposited during the long decline of the Late Paleozoic Ice Age, are characterized overall by higher and more uniform δ13C values (+2 to +5‰) and show no evidence of long-term subaerial exposure. However, these strata record two short-lived excursions toward more negative δ13C values. These excursions occur through intervals that record shifts toward shallower and more restricted conditions in the Orogrande Basin. The timing of these shifts corresponds to two periods of glacial expansion across eastern Australia during Late Sakmarian to Early Artinskian and Kungurian time. These relationships suggest that pulses of glacial expansion in eastern Gondwana were of sufficient magnitude to have caused relative sea-level fall, and possibly environmental change, in the Orogrande Basin. The results from this study suggest that marine chemistry, depositional environments and sea-level in the Orogrande Basin were profoundly influenced by epochs of Gondwanan glaciation. These inferences help improve the understanding of how palaeotropical carbonate systems responded to the effects of cryospheric changes during the acme and waning stages of the Late Palaeozoic Ice Age.
Postmodern Anthropology, Science, and Humanism

Melford Spiro. Anthropological Other or Burmese Brother: Studies in Cultural Analysis. New Brunswick: Transaction Publishers, 1992. xx. 250 pp.
Evoked potentials in the dentate gyrus reflect the retention of past sensory events.

Abstract Averaged sensory evoked potentials were recorded from the outer molecular layer of the dentate gyrus (OM AEP) in freely moving rats trained to criterion performance in a two-tone differential discrimination paradigm. OM AEPs showed consistent fluctuations in amplitude based on the acquired significance of the tones through their association with reward (CS+) or non-reward (CS−). However, the relationship between tone significance and OM AEP configuration was dependent upon the sequence of trials preceding the evoked potential, irrespective of whether the potential was evoked by a CS+ or CS−. Specifically, when the preceding sequence contained an increased number of CS− trials, the amplitude of the initial negative component (N 1 ) of the OM AEP was increased, while that of the slower (N 2 ) component was reduced; conversely, when the preceding sequence contained an increased number of CS+ trials, the amplitude of N 1 was reduced, while that of N 2 was increased. The results suggest that the transmission of sensory information into the dentate gyrus is biased by prior experience.
Informal economic activity: Early thinking, conceptual shifts, continuing patterns and persistent issues – a Michigan study

In this paper we review theoretical perspectives on the informal economy that developed during the period 1958–1992. We describe shifts in thinking in two phases that we identify as =first wave studies‘ and =second wave studies,‘ and we identify a series of critical theoretical issues that emerged from the thinking during these periods. Then, focusing on the state of Michigan, USA, we examine empirical research that was conducted in the second wave and compare the results with a state survey that we conducted in 2005. The overall aim of this paper is to summarize the extent of theoretical and empirical studies of informal economy before the more recent postmodern informed analysis of the 1990s, and to document shifts in patterns of informal economic activity as this is revealed from the research. We conclude with a discussion of theoretical and empirical questions that have begun to be addressed in the last 15 years of what has now been 50 years of research on this topic.
Tranquillitas Ordinis: The Present Failure and Future Promise of American Catholic Thought on War and Peace

In recent years, Roman Catholic bishops and activists have been highly visible in the public debate over issues such as nuclear arms control and U.S. policy in Central America. Until now, however, the evolution of American Catholic thought on these questions has received little attention. This book is the first comprehensive critical analysis of American Catholic thought on war and peace. The author's purpose is to evaluate the post-Vatican II transformation of the Church's approach to war/peace issues and to point a wiser direction for its future development. The book begins with a survey of American Catholicism's rich and sophisticated heritage of moral reasoning on war, peace, and political community. In a major reinterpretation of American Catholic history, Weigel shows how the American Bishops' development of a theology of democracy in the nineteenth and twentieth centuries enriched the Church's classic understanding of peace as political community. Weigel thus challenges the now-prominent idea that the U.S. Catholic bishops were not seriously involved in the war-peace debate until the last decade. A highlight of the book is its detailed intellectual portrait of John Courtney Murray, S.J., whom Weigel calls the finest political theorist ever produced by the American Church. Weigel then demonstrates how, over the past generation, American Catholic intellectuals and publicists began to abandon their heritage, and thereby impoverished the theological and political argument over war and peace, security and freedom. The book analyzes the ideas of seven key figures in the transformation of the American Catholic war/peace debate--Dorothy Day, Gordon Zahn, Thomas Merton, Daniel and Philip Berrigan, James Douglass, and J. Bryan Hehir--and critically explores the U.S. bishops' recent involvement with nuclear and Central American policy. Recovering and developing the classic American Catholic heritage, Weigel argues, is essential to creating a wiser theology and politics whose concern for both peace and freedom challenges realists and idealists alike.
Determination of slow slip episodes and strain accumulation along the Cascadia margin

[1] Continuous GPS stations in the Pacific Northwest Geodetic Array network clearly record subduction-related strain accumulation and slow slip episodes along the Cascadia convergent margin. Many of the slow slip episodes have been correlated in time and space with seismic evidence for nonvolcanic tremor, leading to the previous discovery of episodic tremor and slip (ETS). In this study, we use a hyperbolic tangent curve fitting technique for the identification of slow slip times and displacement magnitudes within the GPS time series, independent of seismic tremor data. We then apply this technique to study the patterns of strain accumulation and release associated with ETS events and characterize patterns of coupling associated with the locked and transition zones of the plate interface. We demonstrate the effectiveness of this automated technique for both identification of slow slip observations and calculation of slow slip displacements. Recurrence patterns in the distribution of GPS observations demonstrate coherence among neighboring stations over time and apparent along-strike segmentation of the subduction interface. When slow slip events are removed from the time series, we can estimate the total site velocities between slow slip events. These velocities decay as depth to the subduction interface increases, but they diverge from the long-term trends expected from the interseismic cycle at ∼30–60 km above the interface, consistent with the location where slow slip displacements occur. Forward modeling of coupling on the plate interface reveals that in between slow slip events there is a patch of at least 30% coupling from 20 to 35 km depth, which is needed to produce the observed back slip displacements. Intriguingly, our best fitting models have a decrease in coupling down to ∼30% at ∼20 km depth followed by a peak of greater than 80% coupling at ∼30–35 km depth, suggesting the source zone for ETS events acts as a distinct locking zone that releases strain more frequently than the updip seismogenic locked zone, although a zone of constant ∼30% coupling cannot be ruled out with this data set. Such a scenario indicates that frictional behavior with depth follows a more complex model than a simple temperature controlled transition. We propose that coupling initially decreases with depth due to a decrease in strength of the overriding lower crust, but then coupling increases again when the subducting plate comes in contact with the stronger overriding mantle.
People with cerebral palsy talk for themselves.

SUMMARY A panel discussion between three people with cerebral palsy and the mother of a cerebral palsied 17–year-old girl was held at the 1971 meeting of the American Academy of Cerebral Palsy. This paper gives extracts of some of the ideas and concerns expressed by the participants. ZUSAMMENFASSUNG Bei dem Kongress der Amerikanischen Akademie fur Cerebralparesen, 1971, wurde eine fachliche Diskussion zwischen drei Patienten mit zentraler Lahmung und der Mutter eines 17 Jahre alten cerebralparetischen Madchens durchgefuhrt. Diese Arbeit gibt einige der Ideen und Sorgen, die von den Diskussionsteilnehmern geausert wurden, wieder. RESUMEN En la reunion de 1971 de la Academia Americana para la paralisis cerebral tuvo lugar un panel de discusion entre 3 personas con paralisis cerebral y la madre de una muchacha de 17 anos afecta de paralisis cerebral. Esta documentacion da resumenes sobre algunas de las ideas y preocupaciones expresadas por los participantes.
Development of group leaders: A pregroup training and supervision model

Abstract This article provides a model for pregroup training and ongoing supervision of master's-level group leaders of career awareness and self-exploration (CASE) groups. Results are reported.
Why it is Important for Social Work Educators to Oppose Racist-Based Anti-Immigration Legislation

(2012). Why it is Important for Social Work Educators to Oppose Racist-Based Anti-Immigration Legislation. Journal of Social Work Education: Vol. 48, No. 2, pp. 197-203.
Biological Assessment of Triazine Dendrimer: Toxicological Profiles, Solution Behavior, Biodistribution, Drug Release and Efficacy in a PEGylated, Paclitaxel Construct

The physicochemical characteristics, in vitro properties, and in vivo toxicity and efficacy of a third generation triazine dendrimer bearing approximately nine 2 kDa polyethylene glycol chains and twelve ester linked paclitaxel groups are reported. The hydrodynamic diameter of the neutral construct varies slightly with aqueous solvent ranging from 15.6 to 19.4 nm. Mass spectrometry and light scattering suggest radically different molecular weights with the former approximately 40 kDa mass consistent with expectation, and the latter 400 kDa mass consistent with a decameric structure and the observed hydrodynamic radii. HPLC can be used to assess purity as well as paclitaxel release, which is insignificant in organic solvents or aqueous solutions at neutral and low pH. Paclitaxel release occurs in vitro in human, rat, and mouse plasma and is nonlinear, ranging from 7 to 20% cumulative release over a 48 h incubation period. The construct is 2-3 orders of magnitude less toxic than Taxol by weight in human hepatocarcinoma (Hep G2), porcine renal proximal tubule (LLC-PK1), and human colon carcinoma (LS174T) cells, but shows similar cytotoxicity to Abraxane in LS174T cells. Both Taxol and the construct appear to induce caspase 3-dependent apoptosis. The construct shows a low level of endotoxin, is not hemolytic and does not induce platelet aggregation in vitro, but does appear to reduce collagen-induced platelet aggregation in vitro. Furthermore, the dendrimer formulation slightly activates the complement system in vitro due most likely to the presence of trace amounts (<1%) of free paclitaxel. An animal study provided insight into the maximum tolerated dose (MTD) wherein 10, 25, 50, and 100 mg of paclitaxel/kg of construct or Abraxane were administered once per week for three consecutive weeks to non tumor bearing athymic nude mice. The construct showed in vivo toxicity comparable to that of Abraxane. Both formulations were found to be nontoxic at the administered doses, and the dendrimer had an acute MTD greater than the highest dose administered. In a prostate tumor model (PC-3-h-luc), efficacy was observed over 70 days with an arrest of tumor growth and lack of luciferase activity observed in the twice treated cohort.
Accurate ion abundance measurements in ion cyclotron resonance mass spectrometry by linear prediction

In standard pulsed ion cyclotron resonance mass spectrometry (ICRMS) mass spectra are generated by converting the time domain signal to the frequency or mass domain by fast Fourier transform (FFT). The FFT requires long acquisition times to acquire high resolution mass spectra. In ICRMS, long acquisition times introduce distortions in the peak intensities of the transformed spectrum that lead to errors in ion abundance. We report here the use of linear prediction methods on data sets collected during much shorter acquisition times to determine actual ion abundances more accurately.
The NK-2 class homeodomain factor CEH-51 and the T-box factor TBX-35 have overlapping function in C. elegans mesoderm development

The C. elegans MS blastomere, born at the 7-cell stage of embryogenesis, generates primarily mesodermal cell types, including pharynx cells, body muscles and coelomocytes. A presumptive null mutation in the T-box factor gene tbx-35, a target of the MED-1 and MED-2 divergent GATA factors, was previously found to result in a profound decrease in the production of MS-derived tissues, although the tbx-35(-) embryonic arrest phenotype was variable. We report here that the NK-2 class homeobox gene ceh-51 is a direct target of TBX-35 and at least one other factor, and that CEH-51 and TBX-35 share functions. Embryos homozygous for a ceh-51 null mutation arrest as larvae with pharynx and muscle defects, although these tissues appear to be specified correctly. Loss of tbx-35 and ceh-51 together results in a synergistic phenotype resembling loss of med-1 and med-2. Overexpression of ceh-51 causes embryonic arrest and generation of ectopic body muscle and coelomocytes. Our data show that TBX-35 and CEH-51 have overlapping function in MS lineage development. As T-box regulators and NK-2 homeodomain factors are both important for heart development in Drosophila and vertebrates, our results suggest that these regulators function in a similar manner in C. elegans to specify a major precursor of mesoderm.
Exhaustibility and the durable-goods monopolist

A model of the durable-goods monopolist is considered in which the monopolist's output is an exhaustible resource. With exhaustibility the monopolist may effectively precommit himself to a range of future production levels. It is shown that this possibility for precommitment may dramatically alter the nature of the durable-goods monopoly equilibrium.
The role of folates in squamous cell carcinoma of the head and neck.

Abstract The primary objective of this review is to explore the hypothesis that folate insufficiency may be important in the pathogenesis of squamous cell carcinomas of the head and neck (SCCHN) and that folate repletion may be an effective component of chemoprevention. The main results are that folate insufficiency disrupts DNA global and specific gene methylation patterns such that the activity of certain tumor suppressor genes such as p16 and possibly p53 may be lost. Folate pool imbalance and impaired repair mechanisms may contribute to DNA instability and strand breaks. Sensitive methods exist for identification of individuals with folate insufficiency in contrast to the relatively insensitive conventional serum or red cell folate assays with broad "normal" ranges. The impact of folate supplementation can thus be quantified. Folate imbalance may result from alterations in folate cellular uptake by the reduced folate carrier (RFC) and/or the folate receptor (FR) and polymorphisms in enzymes important in folate retention such as folylpolyglutamate synthetase and in folate modification such as methylene tetrahydrofolate reductase (MTHFR). Known predisposing factors for SCCHN such as alcohol and tobacco carcinogens may influence folate balance. Folate supplementation may reduce primary or secondary risk of cancer. Formal studies of folate sufficiency in persons at risk for or diagnosed and treated for SCCHN are needed to define the role of folate supplementation in the prevention of these cancers.
Development of bearing friction models from experimental measurements

Abstract For a better understanding of the underlying physics involved in friction phenomena, a carefully controlled experimental study is presented in which the frictional forces and dynamic response of a shaft oscillating within a pair of sleeve bearings were monitored and analyzed in order to gain further insight into the basic phenomenological features of bearing friction forces. Through a qualitative review of the data, it is shown that the trajectory of the bearing force versus slip velocity exhibits an hysteretic-type loop super-imposed on Coulomb and viscous actions. Parametric identification techniques are used to develop a simplified mathematical model incorporating an idealized Coulomb friction element. A comprehensive application of non-linear system identification teniques, to extract more quantitative and less obvious characteristics of the measured frictional behavior, is presented. Processing of the data through the use of a time-domain procedure for the identification of non-linear vibrating structures shows that an optimum (in the least squares sense) non-linear mathematical model can be developed to match, with reasonable accuracy, all of the measured response time histories. Furthermore, the mathematical representation of the model allows convenient separation of the contribution of the equivalent linear and non-linear internal forces developed in the physical system.
Changes in intracranial pressure associated with chest physiotherapy.

Introduction Management of intracranial hypertension is pivotal in the care of brain-injured patients.
Photoelectron counting with an image intensifier tube and a self-scanned photodiode array

A self-scanned photodiode array was fiber-optically coupled to an ITT proximity-focused image intensifier tube. It was determined that a single photoelectron event produces 34,000 charge carriers in a photodiode. This charge is only a factor of 2.8 above the rms noise level of the preamplifier used in the tests, but standard charge-sensitive techniques are at least a factor of 12 better. The image tube and photodiode array combination can be packaged in a disk 5.1 cm in diameter and 2.6 cm thick.
The Multidimensional Anxiety Scale for Children (MASC): Factor Structure, Reliability, and Validity

ABSTRACT Objective To describe the history, factor structure, reliability, and validity of the Multidimensional Anxiety Scale for Children (MASC). Method In two separate school-based population studies, principal-components factor analysis was used, first, to test a theory-driven factor structure, and second, to develop an empirically derived factor structure for the MASC. In a separate study using a clinical population, test-retest reliability at 3 weeks and 3 months, interrater concordance, and convergent and divergent validity were examined. Results The final version of the MASC consists of 39 items distributed across four major factors, three of which can be parsed into two subfactors each. Main and subfactors include (1) physical symptoms (tense/restless and somatic/autonomic), (2) social anxiety (humiliation/rejection and public performance fears), (3) harm avoidance (perfectionism and anxious coping), and (4) separation anxiety. The MASC factor structure, which presumably reflects the in vivo structure of pediatric anxiety symptoms, is invariant across gender and age and shows excellent internal reliability. As expected, females show greater anxiety on all factors and subfactors than males. Three-week and 3-month test-retest reliability was satisfactory to excellent. Parent-child agreement was poor to fair. Concordance was greatest for easily observable symptom clusters and for mother-child over father-child or father-mother pairs. Shared variance with scales sampling symptom domains of interest was highest for anxiety, intermediate for depression, and lowest for externalizing symptoms, indicating adequate convergent and divergent validity. Conclusion The MASC is a promising self-report scale for assessing anxiety in children and adolescents.
Superconductive supercooling and superheating of small cadmium spheres: size effects

Supercooling and superheating have been observed for samples composed of small cadmium spheres of uniform well-defined sizes. The data obtained for large sphere diameters are independent of size and represent, by all indications, ideal bulk properties. The supercooling data for such spheres have been used to obtain the Ginsburg-Landau parameter $\ensuremath{\kappa}$ and, in conjunction with BCS expressions, the penetration depth $\ensuremath{\lambda}$ and the coherence length ${\ensuremath{\xi}}_{0}$. The temperature dependence of the supercooling field ${H}_{\mathrm{sc}}$ shows an anomaly for $t\ensuremath{\sim}0.8$, very similar to that previously reported for Al and Zn. The superheating field of these "bulk" spheres shows strong effects of the nonlocal electrodynamics below ${T}_{c}$. Spheres of diamters equal to or smaller than 10 \ensuremath{\mu} show strong size effects in the supercooling and superheating fields, especially near ${T}_{c}$. The results are examined in the light of existing theories of critical fields for small spheres. A systematic decrease of the critical temperature with sphere size has also been observed. It seems related to a decrease in the gap anisotropy, produced by boundary scattering. These results are analyzed in terms of the theory of Markowitz and Kadanoff.
Development Of In-X Doped Silicon As An Infrared Detector Material

Recently, a class of shallow acceptor levels in silicon, called X-levels, have been discovered which are associated with all the Group III A acceptors. The indium related X-level at 0.113eV appears to be ideally suited to match the 8-12μm atmospheric window. This defect has been shown to arise from a substitutional In and C nearest neighbor pair. We have performed a variety of measurements to determine the feasibility of utilizing the In-X defect in a photoconductor. In particular, silicon crystals heavily doped with both indium and carbon have been grown by thermal gradient transport from indium solutions. Annealing studies have been done to determine whether In-X concentrations in excess of 1-1017cm-3 can be produced in reasonable annealing times. Such a concentration would be necessary to produce detectors with adequate quantum efficiency.© (1981) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Protein phosphatase 2C acts independently of stress-activated kinase cascade to regulate the stress response in fission yeast.

Stress-activated signal transduction pathways, which are largely conserved among a broad spectrum of eukaryotic species, have a crucial role in the survival of many forms of stress. It is therefore important to discover how these pathways are both positively and negatively regulated. Recent genetic studies have implicated protein phosphatase 2C (PP2C) as a novel negative regulator of stress response pathways in both budding and fission yeasts. Moreover, it was hypothesized that PP2C dephosphorylates one or more components of protein kinase cascades that are at the core of stress-activated signal transduction pathways. Herein we present genetic and biochemical studies of the fission yeastSchizosaccharomyces pombe that disprove this hypothesis and indicate that PP2C instead negatively regulates a downstream element of the pathway. First, high expression of PP2C produces phenotypes that are inconsistent with negative regulation of the Wik1-Wis1-Spc1 stress-activated kinase cascade. Second, high expression of PP2C leads to sustained activating tyrosine phosphorylation of Spc1. Third, Spc1-dependent phosphorylation of Atf1, a transcription factor substrate of Spc1, is unaffected by high expression of PP2C. Fourth, high expression of PP2C suppresses Atf1-dependent transcription of a stress-response gene. These studies strongly suggest that PP2C acts downstream of Spc1 kinase in the stress-activated signal transduction pathway.
How Myxobacteria Glide

Background Many microorganisms, including myxobacteria, cyanobacteria, and flexibacteria, move by gliding. Although gliding always describes a slow surface-associated translocation in the direction of the cell's long axis, it can result from two very different propulsion mechanisms: social (S) motility and adventurous (A) motility. The force for S motility is generated by retraction of type 4 pili. A motility may be associated with the extrusion of slime, but evidence has been lacking, and how force might be generated has remained an enigma. Recently, nozzle-like structures were discovered in cyanobacteria from which slime emanated at the same rate at which the bacteria moved. This strongly implicates slime extrusion as a propulsion mechanism for gliding. Results Here we show that similar but smaller nozzle-like structures are found in Myxococcus xanthus and that they are clustered at both cell poles, where one might expect propulsive organelles. Furthermore, light and electron microscopical observations show that slime is secreted in ribbons from the ends of cells. To test whether the slime propulsion hypothesis is physically reasonable, we construct a mathematical model of the slime nozzle to see if it can generate a force sufficient to propel M. xanthus at the observed velocities. The model assumes that the hydration of slime, a cationic polyelectrolyte, is the force-generating mechanism. Conclusions The discovery of nozzle-like organelles in various gliding bacteria suggests their role in prokaryotic gliding. Our calculations and our observations of slime trails demonstrate that slime extrusion from such nozzles can account for most of the observed properties of A motile gliding.
Pediatric cardiac transplantation

Pediatric heart transplantation has undergone major changes over the past two decades, marked by a substantial improvement in survival, reduction in posttransplant complications, and enhancement in quality of life for transplant recipients. Actuarial survival has improved substantially in the last decade. Indications for pediatric heart transplant have changed as surgery for complex congenital heart lesions has evolved. There are now left and right ventricular assist devices that are suitable for use in infants as a bridge to transplantation. New immunosuppressive agents have reduced the risk of rejection while minimizing side effects and strategies to reduce the risk of graft coronary disease are beginning to show promise. Finally, true long-term survival for children after heart transplant has now been demonstrated and quality of life is excellent.
Clinical assessment of a flow-through fluorometric blood gas monitor.

We performed an observational study to evaluate a flow-through fluorometric instrument (Gas-STAT) that continuously measures the carbon dioxide tension (PCO2), oxygen tension (PO2), and pH of blood in the cardiopulmonary bypass circuit. Setup and calibration of the instrument typically required 20 minutes. During bypass, 129 blood samples were drawn from 16 patients for comparison with conventional measurements obtained with a blood gas machine. Data for each variable, within each sensor, were analyzed by linear regression. The ranges of the standard errors of the estimate were 0.7 to 4.2 mm Hg forPCO2, 18.3 to 78.7 mm Hg for the highPO2 range, 1.4 to 7.1 mm Hg for the lowPO2 range, and 0.008 to 0.049 for pH. The regression lines differed from the identity line (P<0.05) in at least one variable in most patients, and large deviations from the line of identity in both slope and intercept were common. Among 58 sensors evaluated, failures occurred in 5 (2.9%) of the 174 optodes, and minor leakage occurred in 2 (3.4%) of the flow-through cells. We conclude that although this flow-through fluorometric instrument is an adequate monitor of trends in blood gases during cardiopulmonary bypass, it is not accurate enough to supplant conventional laboratory measurements.
Histochemical techniques for locating Escherichia coli β-galactosidase activity in transgenic organisms☆

Abstract Escherichia coli β-galactosidase is a commonly used reporter molecule for analyzing gene expression. Recently, β-galactosidase fusions have been applied to a variety of eukaryotic systems. The techniques for constructing and introducing β-galactosidase fusion constructs as well as soluble assays for total enzyme function have been described in detail elsewhere. This article describes histochemical techniques for analyzing organisms that contain a functional β-galactosidase fusion construct. The object is to determine semiquantitatively which cells are expressing the βαlactosidase fusion protein, as well as the subcellular localization of the protein. Due to its prevalence in the author's laboratory, Caenorhabditis elegans is used as a canonical organism for the detailed methods described.
Psychology of a Changing Paradigm: 40+ Years of High-Pressure Metamorphism

The story of ultrahigh-pressure metamorphism (UHPM) is a confused mixture of surprising, sometimes spectacular, discoveries and emotional reactions. Surprisingly, the process has been a repeating cycle of disbelief followed by confirmation, with little evidence that the community response in a given cycle has learned from previous cycles. To this writer's understanding, it began in the early 1960s, before the plate-tectonic revolution, when W. Gary Ernst determined experimentally that the blue amphibole, glaucophane, is stable only at low temperatures and elevated pressures. The implication that glaucophane-bearing rocks, such as those of the Franciscan Complex of northern California, could have been rapidly carried to high pressure and returned to the surface equally rapidly was rejected as impossible. The advent of plate tectonics provided a conceptual answer to the conundrum, but resistance remained, and the concept of tectonic overpressure was invented to explain away the depths implied by experimenta...
Error Exponents for Target-Class Detection with Nuisance Parameters

We study the target class detection performance of a sensor network having a structured topology. The target is in the far-field of the network, located at a distance gamma and angle thetas, and produces a random signal field that is sampled by sensors. It is assumed that samples have a correlation structure and power level that depend on gamma, thetas and the target's class i, i isin {0,1}. We study the Neyman-Pearson miss probability error exponent for this scenario using large deviations theory. When (gamma, thetas) is known, we characterize the properties of the error exponent as a function of signal and design parameters. When (gamma, thetas) has at least one unknown component, we use the theory of adaptive tests to prove that there exists a test that achieves the same error exponent as if (gamma, thetas) were known in some scenarios, but that there exists no such test in others.
Central nervous system and renal investigations in patients with Lowe syndrome

We describe three patients with Lowe (oculocerebrorenal) syndrome, emphasizing primarily the central nervous system and renal pathology. Using magnetic resonance imaging, we noted diffuse high T2 signals periventricularly, indicating significant white matter destruction, which may be responsible in part for the mental retardation, seizure disorder, hypotonia, and areflexia observed in the patients. In contrast to previously published reports, there was minimal renal tubular dysfunction; however, proteinuria was significantly increased in all patients. We believe that the observed proteinuria is primarily the result of glomerular pathology rather than renal tubular dysfunction and may represent a net loss of negative charges within the glomerular filter. This loss of charge may be linked to the increased excretion of glycosaminoglycans in the urine.
Development of a partitioned-biomass model for rooted macrophyte growth

Abstract Many surface waters support excessive growth of several rooted macrophyte species. This paper presents a macrophyte growth model to facilitate modeling the growth of several macrophyte species which exhibit distinct patterns of growth and development. The model partitions the biomass of each species according to the phenological stages of plant development including growth, maturation, senescence, and dormancy. The partitioned-biomass model was demonstrated for the growth of Elodea canadensis Michx. and Potamogeton crispus L. in Spring Creek, a shallow fourth-order stream in central Pennsylvania. The structure of the model could be adapted to a wide variety of macrophytes and aquatic ecosystems.
Adolescence terminable and interminable: When does adolescence end?

The question of when adolescence ends and young adulthood begins is considered. Throughout, it is addressed in terms of the theory of broad and narrow socialization, which emphasizes the cultural context of development. The question is approached from cognitive, emotional, and behavioral perspectives, then from the perspective of role transitions (such as marriage and parenthood). The idea of an extended path from adolescence to adulthood is discussed, and the concept of emerging adulthood is presented. It is suggested that in most non-Western cultures the entrance to adulthood is socially defined and marked by a social event, usually marriage. In the contemporary West, however, where there is a strong emphasis on independence and individualism, the entrance to adulthood is defined and marked individually. Consequently, it is likely to be based on the achievement of residential and financial independence as well as on the attainment of cognitive self-sufficiency, emotional self-reliance, and behavioral self-control. Thus in the contemporary West the passage from adolescence to young adulthood is a process that is gradual and may take many years.
Elementary excitations in alkali-metal overlayers probed by electron-energy-loss spectroscopy: Quantum-mechanical effects

The spectrum of electronic excitations of Na and K overlayers adsorbed on Al(111) has been studied by means of electron-energy-loss-spectroscopy experiments, and self-consistent, dynamical-response calculations. Losses are observed in two distinct energy and coverage domains. The loss observed during the formation of the second atomic layer shows novel features, which are traced to the intrinsic quantum-mechanical nature of the excitations being probed, and their spatial confinement by the overlayer.
Influence of interaction of environmental risk factors and sensitization in young asthmatic children

Abstract Background: The increasing prevalence of asthma and allergy in many countries demands evaluation of potential risk factors to improve the possibility of prevention. Objective: We studied the association between exposure to cat and dog allergen and allergic sensitization in young children with asthma and interactions with potential environmental risk factors. Methods: One hundred eighty-nine young children with asthma were evaluated. IgE antibodies to cat and dog were analyzed. Questionnaires were filled in focusing on exposure to cats and dogs, environmental tobacco smoke (ETS), and signs of home dampness as indicated by window pane condensation (WPC) during the first years of life. House dust was analyzed for content of cat (Fel d 1) and dog (Can f 1) allergen. Results: There was a strong association between the degree of reported exposure to cat and dog and the concentration of the respective allergens in floor dust. A dose-response relationship was found between cat exposure, measured as either reported degree of cat exposure or cat allergen levels in dust, and sensitization both to cat and dog. No such relationship was found between exposure and sensitization to dog. WPC increased the risk for sensitization to cat (odds ratio=2.6, 95% confidence interval 1.2-5.8), whereas ETS strongly tended to do so both to cat and dog. Interaction was found between exposure to ETS, WPC, and high levels of cat allergen (>8 μg/g dust). The presence of all 3 risk factors revealed a multiplicative interaction with a high risk of sensitization to cat (odds ratio=42.0, 95% confidence interval 3.7-472.8). Conclusions: Keeping cats indoors may be a health hazard for infants and young children at risk for development of asthma, particularly when they live in a damp house and their parents smoke. (J Allergy Clin Immunol 1999;104:755-62.)
Crystal Structure Studies of RNA Duplexes Containing s(2)U:A and s(2)U:U Base Pairs.

Structural studies of modified nucleobases in RNA duplexes are critical for developing a full understanding of the stability and specificity of RNA base pairing. 2-Thio-uridine (s2U) is a modified nucleobase found in certain tRNAs. Thermodynamic studies have evaluated the effects of s2U on base pairing in RNA, where it has been shown to stabilize U:A pairs and destabilize U:G wobble pairs. Surprisingly, no high-resolution crystal structures of s2U-containing RNA duplexes have yet been reported. We present here two high-resolution crystal structures of heptamer RNA duplexes (5′-uagcs2Ucc-3′ paired with 3′-aucgAgg-5′ and with 3′-aucgUgg-5′) containing s2U:A and s2U:U pairs, respectively. For comparison, we also present the structures of their native counterparts solved under identical conditions. We found that replacing O2 with S2 stabilizes the U:A base pair without any detectable structural perturbation. In contrast, an s2U:U base pair is strongly stabilized in one specific U:U pairing conformation out of...
An Outline of German Grammar on the Mnemonic Scheme of Three, Five, Eight

Author's Summary— The necessarily analytical approach to a foreign language usually results in the student's never seeing the “forest for the trees.” The following simple outline of German grammar is offered as a kind of compass, by which he can orientate himself in the “forest” while acquiring familiarity with the various “trees.”
Synthesis of Covariant Particle Equations

By combining two irreducible representations of the proper inhomogeneous Lorentz group, certain irreducible unitary representations of the complete Lorentz group including space and time inversion are obtained, together with a Schr\"odinger equation whose solutions constitute the representation space for these representations. The representations thus define a "canonical" form for covariant particle theories, in which not only the wave equations but the manner in which the wave functions transform under Lorentz transformations is prescribed. It is shown that by a suitable choice of representation, the Dirac, Klein-Gordon, and Proca equations can all be reduced to this canonical form. It is further shown that in the representation space provided, several possibilities exist for the identification of the transformations to be associated with space inversion, time inversion, and charge conjugation, thus suggesting the existence of several distinct relativistic theories for particles of any given spin. Conjectures are made as to the physical significance of these different possibilities when the equations are second-quantized. It is shown that each of the conventional theories employs only one of the available possibilities for these transformations, the choices being different for integral and half-integral spin theories.
Reconstitution of the lipid-depleted pyruvate oxidase system of Escherichia coli: the palmitic acid effect.

Abstract Previous work has shown that the coupling of the soluble Escherichia coli pyruvate oxidase to a lipid-depleted membrane terminal electron transport system requires the addition of ubiquinone and a neutral lipid fraction (C. Cunningham and L. P. Hager (1975) J. Biol. Chem. 250 , 7139–7146). The active factor present in the neutral lipid fraction has now been isolated and characterized. NMR, uv, and mass spectroscopic analysis identifies palmitic acid as the active component. A comparison of palmitic acid with other fatty acids of varying chain lengths indicates that most fatty acids having chain lengths in the range C 12 to C 20 have comparable activity to palmitic acid. Exceptions are stearic and arachidic acid which have greatly reduced activity. Fatty acids of C 6 to C 10 chain length showed about one third the activity of palmitic acid. Fatty acids having chain lengths of 2 to 5 carbon atoms are essentially inactive. The carboxyl function of the fatty acid is required for activity. Derivatives of fatty acids in which the carboxyl group had been modified to an alcohol, aldehyde, or methyl ester function show greatly dimished activity. Both the cis and trans forms of unsaturated long-chain fatty acids are active. The stimulation of the electron transfer reaction by fatty acids occurs at the ubiquinone level of the electron transport chain. Ubiquinone-30 is rapidly reduced by pyruvate oxidase only in the presence of palmitic acid.
Traction between a web and a smooth roller

Web traction over rollers is known to deteriorate due to air entrainment at high web speeds. In this paper, a general model is presented to predict the traction capability of an impermeable web over a smooth roller. The model considers the effects of the web and roller speeds, roller radius, combined roughness of the two surfaces, web tension and thickness, friction coefficient, and compressible air bearing. The change of tension ΔN due to mechanical slip between the roller and the web is calculated by a simultaneous solution of the in-plane and out-of-plane equilibrium of the web and the compressible Reynolds lubrication equation. The problem is nondimensionalized and the effects of nine of the eleven nondimensional parameters on traction are investigated for a range of values. Formulas involving the nondimensional parameters for the traction capability are presented in two-variable polynomial forms.
The use of advanced technology for visual inspection training

In the past, training with traditional methods was shown to improve inspection performance. However, advances in technology have automated training and revolutionized the way training will be delivered in the future. Examples of such technology include computer-based simulators, digital interactive video, computer-based training, and intelligent tutoring systems. Despite the lower cost and increased availability of computer technology, the application of advanced technology to training within the manufacturing industry and specifically for inspection has been limited. In this vein, a case study is presented which shows how advanced technology along with our basic knowledge of training principles, can be used to develop a computer-based training program for a contact lens inspection task. Improvements due to computer-based inspection training were measured in an evaluation study and are reported.
Synthesis of small heat-shock proteins is part of the developmental program of late seed maturation.

Small heat-shock proteins (sHSPs) accumulate in plants in response to high-temperature stress. Specific sHSPs, the cytosolic class I and class II proteins, are also expressed in the absence of stress in maturing seeds of several species, and a role for these proteins in desiccation tolerance, dormancy, or germination has been hypothesized. We demonstrate that class I sHSPs are expressed during Arabidopsis seed development in a pattern similar to that previously observed in other species: they are first detected during mid-maturation, are most abundant in dry seeds, and decline rapidly during germination. Although the class I sHSP family in Arabidopsis appears to consist of four genes, expression of a single gene, Athsp17.4, accounts for the majority of sHSPs in maturing seeds. sHSP levels were also examined in seeds of several Arabidopsis mutants with reduced sensitivity to abscisic acid inhibition, including aba1, abi1 and abi2, abi3–1, abi3–6, abi4, and abi5–1. The abi3–1 mutant has 10-fold reduced levels of sHSPs; sHSPs are undetectable in the abi3–6 mutant. All other mutants were indistinguishable from wild type. These results suggest that sHSP expression in seeds is regulated by the ABI3 response pathway and wild-type levels of sHSPs are not sufficient for seed dormancy and not necessary for desiccation tolerance. However, roles in either process cannot be ruled out. In total the data indicate that the expression of sHSPs in seeds is part of the normal developmental program of late seed maturation and the presence of sHSPs has adaptive significance for plant reproduction.
Characterization of two ammonia-oxidizing bacteria isolated from reactors operated with low dissolved oxygen concentrations.

Aims: To obtain ammonia-oxidizing bacterial (AOB) strains inhabiting low dissolved oxygen (DO) environments and to characterize them to better understand their function and ecology. Methods and Results: Using a serial dilution method, two AOB strains (ML1 and NL7) were isolated from chemostat reactors operated with low DO concentrations (0·12–0·24 mg l−1). Phylogenetically, strains ML1 and NL7 are affiliated to AOB within the Nitrosomonas europaea and Nitrosomonas oligotropha lineages, respectively. Kinetically, strain ML1 had high affinity for oxygen (0·24 ± 0·13 mg l−1) and low affinity for ammonia (1·62 ± 0·97 mg N l−1), while strain NL7 had high affinity for ammonia (0·48 ± 0·35 mg l−1), but a surprisingly low affinity for oxygen (1·22 ± 0·43 mg l−1). A co-culture experiment was used to iteratively estimate decay constants for both strains. Conclusions: The results indicated that AOB without high affinity for oxygen may have other mechanisms to persist in low DO environments, with high affinity for ammonia being important. Significance and Impact of the Study: This study provides a method to determine AOB growth kinetic parameters without assuming or neglecting decay constant. And, this is the first report on oxygen affinity constant of a N. oligotropha strain.