cssi/SciSciGPT-SciSciNet huggingface dataset:
Effects of prenatal bacterial infection on cognitive performance in early childhood

Background Previous epidemiologic studies have reported adverse neurodevelopmental sequelae following prenatal infectious exposure, yet long-term effects estimated from these observational studies are often subject to biases due to confounding and loss to follow-up. Objectives We demonstrate the joint use of inverse probability (IP) treatment and censoring weights when evaluating neurotoxic effects of prenatal bacterial infection. Methods We applied IP weighting for both treatment and censoring to estimate the effects of maternal bacterial infection during pregnancy on mean intelligence quotient (IQ) scores measured at age 7 using the Wechsler Intelligence Scale for Children. Participants were members of a population-based pregnancy cohort recruited in the Boston and Providence sites of the Collaborative Perinatal Project between 1959 and 1966 (n = 11 984). We calculated average treatment effects (ATE) and average treatment effects on the treated (ATT) using IP weights estimated via generalized boosted models. Results ATE- and ATT-weighted mean IQ scores were lowest among offspring exposed to multi-systemic bacterial infection during pregnancy and highest for those unexposed. The effects of prenatal bacterial infection were greater among male offspring, particularly on performance IQ scores. Offspring who were exposed to multi-systemic bacterial infection in the third trimester displayed the largest reduction in mean full-scale, verbal, and performance IQ scores at age 7 compared to those unexposed or exposed in earlier trimesters. Conclusions We find that prenatal bacterial infection is associated with cognitive impairments at age 7. Associations are strongest for more severe infections, that occur in the third trimester, and among males. Public health intervention targeting bacterial infection in pregnant women may help enhance the cognitive development of offspring.
Enlightenment on Life: Love Between an Older Woman and a Younger Man

This chapter compares Chinese television dramas with television dramas from Taiwan, Japan, and South Korea, analyzing the differences and similarities of gender roles and relationships in these programs. The difference in age between romantic partners is still a primary concern in East Asian culture. While Japanese television is more tolerant of relationships between older women and younger men, television dramas from China, Taiwan, and South Korea still follow the patriarchal portrayal of gender roles in terms of the woman’s greater age. These dramas depict older women with strong personalities and special talents; however, instead of furthering their own self-realization, they are required to help their men become prototypically masculine. This type of representation reveals that gender relationships are still limited by cultural stereotypes: powerful men and caring women. The female characters’ seniority is represented as a flaw, even though they are portrayed as strong and capable.
Reproducibility and replicability: opportunities and challenges for geospatial research

A cornerstone of the scientific method, the ability to reproduce and replicate the results of research has gained widespread attention across the sciences in recent years. A corresponding burst of ...
Mechanisms that ensure monogamous mating in Saccharomyces cerevisiae

Haploid cells of the budding yeast Saccharomyces cerevisiae communicate using secreted pheromones and mate to form diploid zygotes. Mating is monogamous, resulting in the fusion of precisely one cell of each mating type. Monogamous mating in crowded conditions, where cells have access to more than one potential partner, raises the question of how multiple-mating outcomes are prevented. Here we identify mutants capable of mating with multiple partners, revealing the mechanisms that ensure monogamous mating. Before fusion, cells develop polarity foci oriented toward potential partners. Competition between these polarity foci within each cell leads to disassembly of all but one focus, thus favoring a single fusion event. Fusion promotes the formation of heterodimeric complexes between subunits that are uniquely expressed in each mating type. One complex shuts off haploid-specific gene expression, and the other shuts off the ability to respond to pheromone. Zygotes able to form either complex remain monogamous, but zygotes lacking both can re-mate.
Environmental and host factors that contribute to prion strain evolution.

Prions are novel pathogens that are composed entirely of PrPSc, the self-templating conformation of the host prion protein, PrPC. Prion strains are operationally defined as a heritable phenotype of disease that are encoded by strain-specific conformations of PrPSc. The factors that influence the relative distribution of strains in a population are only beginning to be understood. For prions with an infectious etiology, environmental factors, such as strain-specific binding to surfaces and resistance to weathering, can influence which strains are available for transmission to a naive host. Strain-specific differences in efficiency of infection by natural routes of infection can also select for prion strains. The host amino acid sequence of PrPC has the greatest effect on dictating the repertoire of prion strains. The relative abundance of PrPC, post-translational modifications of PrPC and cellular co-factors involved in prion conversion can also provide conditions that favor the prevalence of a subset of prion strains. Additionally, prion strains can interfere with each other, influencing the emergence of a dominant strain. Overall, both environmental and host factors may influence the repertoire and distribution of strains within a population.
Optimal Planning Over Long and Infinite Horizons for Achieving Independent Partially-Observable Tasks That Evolve Over Time

We focus on long-sighted planning for a class of problems with multiple independent tasks that are partially observable and evolve over time. An example problem that falls into this class is a robot waiting multiple tables, referred to as tasks, in a restaurant where customers’ satisfaction is partially observable and evolves over time. Our recent work exploits the structure found in these problems, namely the independence between the tasks, to optimally and efficiently plan for a short fixed planning horizon. Selecting the right planning horizon can be challenging since an overly short horizon may result in a low-quality solution while supporting a longer horizon quickly becomes computationally impractical. In this paper, we address this challenge. In particular, we extend the recent work to provide efficient planning over long fixed-length horizons without discounting and infinite-length horizons with discounting. The key idea we exploit to achieve efficiency is to compute lower and upper-bounds on the value of an optimal solution for variable horizons which allow us to terminate the search early while guaranteeing optimality. We present the algorithm, analyze its theoretical properties, and demonstrate its efficiency on the waiting tables domain.
Sex Object vs. Athlete: Boys’ and Men’s Responses Toward Sexualized Male Athletes

Using a between-participants experimental paradigm, the present study investigated U.S. adolescent boys’ (n = 96) and college men’s (n = 194) attitudes toward media images of male athletes as well as their thoughts about the athletes. Participants viewed either sexualized (i.e., skin exposed, sexual pose) or performance (i.e., in uniform and in action poses on the field/court) images of male athletes. They then rated the athletes’ competence, esteem, and sexual appeal and completed a writing task about their reactions to the images. Male viewers rated the sexualized athletes lower in competence and esteem and higher in sexual appeal compared to the performance athletes. These results have implications for advocacy efforts calling for less sexualization in today’s media environment.
Clustering using adaptive self-organizing maps (ASOM) and applications

This paper presents an innovative, adaptive variant of Kohonen's self-organizing maps called ASOM, which is an unsupervised clustering method that adaptively decides on the best architecture for the self-organizing map. Like the traditional SOMs, this clustering technique also provides useful information about the relationship between the resulting clusters. Applications of the resulting software to clustering biological data are discussed in detail.
Language, discourse and power in African American culture

African American language is central to the teaching of linguistics and language in the United States, and this book, in the series Studies in the Social and Cultural Foundations of Language, is aimed specifically at upper level undergraduates and graduates. It covers the entire field - grammar, speech, and verbal genres, and it also discusses the various historical strands that need to be identified in order to understand the development of African American English. The first section deals with the social and cultural history of the American South, the second with urban and northern black popular culture, and the third with policy issues. Morgan examines the language within the context of the changing and complex African American and general American speech communities, and their culture, politics, art and institutions. She also covers the current heated political and educational debates about the status of the African American dialect.
Adequacy in Crisis Negotiation Training

(2003). Adequacy in Crisis Negotiation Training. Journal of Police Crisis Negotiations: Vol. 3, No. 1, pp. 115-120.
A review of subterranean termite control practices and prospects for integrated pest management programmes

Soil insecticide barriers have been the single most important tool for subterranean termite control in the last half century, but limitations with current soil termiticides have provided the impetus to look for alternatives in recent years. One such alternative is the monitoring--baiting programme. Monitoring stations to detect termites are placed in the soil surrounding a structure. Once termites are found in the stations, monitoring devices are replaced with slow-acting baits such as the chitin synthesis inhibitor, hexaflumuron. Field studies have indicated that termite colonies were eliminated using less than 1 g of hexaflumuron. After the elimination, monitoring resumes and bait is applied if new termite activity is detected. The monitoring and baiting procedure form the basis for an ongoing programme to protect structures from subterranean termite infestation. Although the cost--benefit model developed for agricultural integrated pest management cannot be applied directly to termite control, the underlying concept for using a cost-effective approach remains the same. The benefits of the monitoring--baiting programme over conventional soil treatment are a reduction in pesticide applied per unit and the elimination of termite populations near structures, resulting in the reduction of liability and damage potential. It is expected that the data management system when used in conjunction with the monitoring--baiting programme will provide a database to improve its cost-effectiveness continuously.
Syntactic Software Merging

Software merging is the process of combining multiple existing versions of a source file, to produce a new version. Typically, the goal is for the new version to implement some kind of union of the features implemented by the existing versions. A variety of merge tools are available, but software merging is still a tedious process, and mistakes are easy to make. This paper describes the fundamentals of merging, surveys the known methods of software merging, including a method based on programming-language syntax, and discusses a set of tools that perform syntactic merging.
Information–Theoretic nonstationary source separation

Blind source separation aims at recovering the original source signals given only observations of their mixtures. Some common approaches to the source separation problem include second or higher order statistics based methods, and independent component analysis. Most of these methods are developed in the time domain, and thus inherently assume the stationarity of the underlying signals. Since most real life signals of interest are non–stationary, there have been efforts to perform source separation in the time–frequency domain. In this paper, we propose a new approach for source separation on the time–frequency plane using an information–theoretic cost function. Jensen–Renyi divergence, as adapted to time–frequency distributions, is introduced as an effective cost function to extract sources that are disjoint on the time–frequency plane. The sources are extracted through a series of Givens rotations and the optimal rotation angle is found using the steepest descent algorithm. The proposed method is applied to several example signals to illustrate its effectiveness and the performance is quantified through simulations.
Multiple-Population Moment Estimation: Exploiting Interpopulation Correlation for Efficient Moment Estimation in Analog/Mixed-Signal Validation

Moment estimation is an important problem during circuit validation, in both presilicon and postsilicon stages. From the estimated moments, the probability of failure and parametric yield can be estimated at each circuit configuration and corner, and these metrics are used for design optimization and making product qualification decisions. The problem is especially difficult if only a very small sample size is allowed for measurement or simulation, as is the case for complex analog/mixed-signal circuits. In this paper, we propose an efficient moment estimation method, called multiple-population moment estimation (MPME), that significantly improves estimation accuracy under small sample size. The key idea is to leverage the data collected under different corners/configurations to improve the accuracy of moment estimation at each individual corner/configuration. Mathematically, we employ the hierarchical Bayesian framework to exploit the underlying correlation in the data. We apply the proposed method to several datasets including postsilicon measurements of a commercial high-speed I/O link, and demonstrate an average error reduction of up to $2\times$ , which can be equivalently translated to significant reduction of validation time and cost.
Quantum mechanics of systems periodic in time

Some expressions for the time evolution of quantum-mechanical systems with Hamiltonians periodic in time, derivable from the work of Shirley and applied by Young, Deal, and Kestner and Haeberlen and Waugh---all for finite-basis-set systems---are derived for a general system (possibly infinite Hilbert space). These results suggest a new type of approximation to the time-evolution operator, one which is exact at multiples of the period of the Hamiltonian. Comparison is made to an exactly soluble problem, namely, a nonrelativistic hydrogen atom in a circularly polarized monochromatic field.
A double-blind, placebo-controlled trial of modafinil for cocaine dependence.

Despite years of active research, there are still no approved medications for the treatment of cocaine dependence. Modafinil is a glutamate-enhancing agent that blunts cocaine euphoria under controlled conditions, and the current study assessed whether modafinil would improve clinical outcome in cocaine-dependent patients receiving standardized psychosocial treatment. This was a randomized, double-blind, placebo-controlled trial conducted at a university outpatient center (from 2002 to 2003) on a consecutive sample of 62 (predominantly African American) cocaine-dependent patients (aged 25–63) free of significant medical and psychiatric conditions. After screening, eligible patients were randomized to a single morning dose of modafinil (400 mg), or matching placebo tablets, for 8 weeks while receiving manual-guided, twice-weekly cognitive behavioral therapy. The primary efficacy measure was cocaine abstinence based on urine benzoylecgonine levels. Secondary measures were craving, cocaine withdrawal, retention, and adverse events. Modafinil-treated patients provided significantly more BE-negative urine samples (p=0.03) over the 8-week trial when compared to placebos, and were more likely to achieve a protracted period (⩾3 weeks) of cocaine abstinence (p=0.05). There were no serious adverse events, and none of the patients failed to complete the study as a result of adverse events. This study provides preliminary evidence, which should be confirmed by a larger study, that modafinil improves clinical outcome when combined with psychosocial treatment for cocaine dependence.
Synthesis versus imitation: evaluation of a medical student simulation curriculum via Objective Structured Assessment of Technical Skill.

Background Given the investment that programs make to simulation training, it is important to evaluate its effects on student learning. Tasks (e.g., gowning and gloving, suturing) are typically taught in isolation over a series of linked sessions. This study assessed students' ability to integrate such tasks while executing an unrehearsed procedure before and after a new simulation curriculum was introduced. Methods An Objective Structured Assessment of Technical Skill (OSATS) was administered to 26 students in the 2007 clerkship who received a 3-hour orientation to the operating room followed by a 3-hour animate laboratory, and to 167 students in the 2008 clerkship who received a 9-hour simulation skills curriculum. The OSATS task involved a live volunteer "patient" with an arm laceration. Students had 40 minutes to explain the procedure, start an intravenous line, administer a local anesthetic, prepare the wound (pig's foot), gown and glove, and suture the wound. The OSATS was scored by trained raters using a tool with 57 checklist and 7 global rating items. Its internal consistency reliability was 0.82. Independent sample t tests were used to analyze differences between "pre" and "post" groups. Results Mean scores were significantly higher for the post group for the checklist score (83% vs 62%, p Conclusions The revised curriculum had a positive impact on students' mastery of basic surgical skills, despite the loss of the animal laboratory. Implications for instruction include greater use of discovery-learning techniques to teach productive versus reproductive skills.
Secondary radiation and the dentist.

Secondary radiation is produced when­ ever a body of matter is exposed to roentgen-ray radiation. Most of the secondary radiation present in a dental office origi­ nates at the face of the patient; however, the air, the dental equipment and any­ thing else lying in the path of the use­ ful beam of roentgen rays will also emit secondary radiation. Secondary radia­ tion scatters in all directions from its place of origin while the x-ray machine is operating, and ceases when the expo­ sure is terminated. For purposes of clarity, the following definitions of symbols are included: 1. The unit of quantity of roentgenray radiation is the “roentgen,” desig­ nated by the symbol “r.” 2. The unit of electrical pressure ap­ plied to an x-ray tube is the “peak kilo­ volt” designated by the symbol “kvp.” 3. The unit of quantity of electrical current passing through an x-ray tube is the “milliampere,” designated by the symbol, “ma.” 4. The unit of daily usage of an x-ray , • , “ma. sec.” . . machine is the -----:--------. This unit is day the product of the number of milliamperes of current flowing through an x-ray tube and the number of seconds that the machine is operated per day. The National Committee on Radiation Protection1'3 has issued recently revised recommendations relative to permissible radiation exposures of persons who are occupationally exposed to radiation. The net effect of these recommendations is to reduce the average basic maximum exposure limit from 0.3 to 0.1 r per week. In light of present knowledge, the exposure of one who is exposed occupa­ tionally to roentgen-ray radiation at the rate of 0.100 r per week, is not expected to cause detectable bodily injury at any time during his lifetime. If a dentist always avoids the path of the useful roentgen-ray beam and if the manufacturer of his x-ray machine has built the head of the machine prop­ erly so as to keep leakage radiation below the recommended limits for diagnostic x-ray machines,4 then the only major source of radiation that presents any ap­ preciable hazard to the dentist is the secondary radiation that scatters from the patient’s head. The recommended limits4 for diagnostic x-ray machines are as follows:
Fluidic encapsulation in SU-8 μ-reservoirs with μ-fluidic through-chip channels

Abstract A process has been developed that allows encapsulation of an aqueous solution within a micrototal analysis system (μ-TAS) device. This device, a microtransdermal glucose sensor called B-FIT is cast in the photopolymer SU-8. A 50 nl μ-reservoir is filled and sealed by means of bonding two cured SU-8 surfaces using a thin layer of uncured SU-8. The μ-reservoir is bound by two membranes of 5 and 20–40 μm thick. Upon electrolysis of the encapsulated fluid by applying 2.6 V (or more, depending on the desired rate of fluid release) to two electrodes within the μ-reservoir, expansion of the created gas instantly ruptures the 5 μm membrane in a controlled fashion at a scoring mark that was fabricated by thinning the 5 μm membrane to 2–3 μm by reactive ion etching. The fluid exits the μ-reservoir and moves up the adjacent μ-capillaries through the entire chip. The technique of encapsulating fluid within MEMS devices offers possibilities for drug delivery systems.
Multiscale topo-morphologic opening of arteries and veins: a validation study on phantoms and CT imaging of pulmonary vessel casting of pigs

Distinguishing pulmonary arterial and venous (A/V) trees via in vivo imaging is a critical first step in the quantification of vascular geometry for purposes of determining, for instance, pulmonary hypertension, detection of pulmonary emboli and more. A multi-scale topo-morphologic opening algorithm has recently been introduced by us separating A/V trees in pulmonary multiple-detector X-ray computed tomography (MDCT) images without contrast. The method starts with two sets of seeds - one for each of A/V trees and combines fuzzy distance transform, fuzzy connectivity, and morphologic reconstruction leading to multi-scale opening of two mutually fused structures while preserving their continuity. The method locally determines the optimum morphological scale separating the two structures. Here, a validation study is reported examining accuracy of the method using mathematically generated phantoms with different levels of fuzziness, overlap, scale, resolution, noise, and geometric coupling and MDCT images of pulmonary vessel casting of pigs. After exsanguinating the animal, a vessel cast was generated using rapid-hardening methyl methacrylate compound with additional contrast by 10cc of Ethiodol in the arterial side which was scanned in a MDCT scanner at 0.5mm slice thickness and 0.47mm in plane resolution. True segmentations of A/V trees were computed from these images by thresholding. Subsequently, effects of distinguishing A/V contrasts were eliminated and resulting images were used for A/V separation by our method. Experimental results show that 92% - 98% accuracy is achieved using only one seed for each object in phantoms while 94.4% accuracy is achieved in MDCT cast images using ten seeds for each of A/V trees.
POLLUTION DISCLOSURES, POLLUTION PERFORMANCE AND ECONOMIC PERFORMANCE

Abstract This study examines the association between pollution disclosures and pollution performance and between pollution disclosures and economic performance for firms in highly polluting industries. An index of pollution disclosures is developed and correlated with indices of pollution performance and economic performance. The results confirm earlier findings that there is no association between pollution disclosures and pollution performance. As far as the association between economic performance and pollution disclosures is concerned, the results show that the subgroup of large firms with poor economic performance provides the most detailed pollution information. For smaller firms there is no association between economic performance and pollution disclosures.
Relationship between peroxyacetyl nitrate and nitrogen oxides in the clean troposphere

The first study is presented in which the mixing ratios of peroxyactyl nitrate (PAN) and nitrogen oxides, as well as those of peroxypropionyl nitrate and O3 and relevant meteorological parameters, were measured concurrently at a location that receives clean, continental air. The results show that, in clean conditions, nitrogen oxides present in the form of PAN can be as much or more abundant than the inorganic form. In addition, PAN can be an important source of peroxyacetyl radicals which may be important to oxidation processes in the gas as well as liquid phases.
Pollinator behaviour and natural selection for flower colour in Delphinium nelsonii

Evolutionary biologists continue to disagree about the relative importance of natural selection, drift and phylogenetic constraint in determining characteristics of an organism1. Because of the difficulty of identifying examples of selection in nature there are few rigorous field studies of selection2–6. We have been studying selection on flower colour in the small perennial larkspur Delphinium nelsonii, a native to mountains of the western USA. Previously we showed that white-flowered forms, which are very rare in natural populations, produce fewer seeds than their common blue-flowered conspecifics, and that this selective disadvantage results from partial discrimination against white flowers by bumblebee and hummingbird pollinators7. Here we present evidence that discrimination occurs because white flowers have inferior ‘nectar guides’ and therefore require longer handling times than blue flowers. Pollinators may thus experience lower net rates of energy intake on white flowers, a sufficient reason for undervisitation by optimally-foraging animals.
Project Organizations as Social Networks

High-performance teams achieve outcomes that exceed the expectations of the project and often demonstrate unique or innovative approaches within a final solution. The foundation of this high performance is the ability to focus on the success of the team over individual objectives. However, the recognition of this emphasis is based on the establishment of professional trust and strong communications between the team members. The social network model of construction introduced a dual-focused approach to enhancing these elements and creating high-performance project teams. The approach emphasizes balancing both a traditional project management emphasis on efficiency of communications with a focus on the social factors that move the project team from efficient to effective. In this paper, the model is extended to present the results of four studies of organizations that are full-service engineering companies that also provide construction oversight services. The paper presents the results of these studies in terms of the social network model and the achievement of high performance in the project teams. Analytical and graphical results are presented based on social network analysis techniques to provide a multiperspective analysis of the project teams.
Deep electron traps in hydrogenated amorphous silicon

Deep-level-transient-spectroscopy measurements on both Schottky barrier and $p\ensuremath{-}i\ensuremath{-}n$ $a$-Si:H solar cell structures reveal deep electron traps. The unique feature of these traps, whose activation energy varies between 0.5 and 1.5 eV, depending on the sample, is that electron capture is thermally activated. This activation energy is close to the trap energy. These traps are also associated with metastable changes in solar cells.
Maximal monotone operators and nonlinear integral equations of Hammerstein type

A nonlinear integral equation of Hammerstein type is one of the form \( u(x) + \int_{G} {K(x,\,y)f(y,\,u(y))dy} = w(x). \)
Sustained Excitatory Synaptic Input to Motor Cortex Neurons in Awake Animals Revealed by Intracellular Recording of Membrane Potentials

1. Most of the intracellular electrophysiological data on cortical neurons has been obtained in anesthetized or reduced preparations, and differs from observations in awake, intact animals. To determine whether these differences are due to experimental techniques or physiological factors, we recorded membrane potentials intracellularly from motor cortex neurons in chronically prepared cats and monkeys under Nembutal-anesthetized, Halothane-anesthetized, and unanesthetized conditions, or during transitions between anesthetized and awake conditions. 2. Resting membrane potentials were found to depend on the anesthetic state of the animal. Membrane potentials of neurons recorded in awake animals were more depolarized than those recorded in the anesthetized state. In the awake state membrane potentials were all less than -65 mV. 3. The input resistance of neurons recorded in awake animals were significantly smaller than those measured in the anesthetized state. Action potentials recorded in awake animals typically showed an undershoot (i.e. negative values at peak), implying that voltage-dependent conductances may be altered. Undershoot of the action potential was more prominent in pyramidal tract neurons (PTNs) than non-PTNs. 4. These data suggested that in awake animals motor cortex neurons, especially PTNs, receive sustained excitatory synaptic input or neuro-modulatory activities.
Primary Severe Acute Respiratory Syndrome Coronavirus Infection Limits Replication but Not Lung Inflammation upon Homologous Rechallenge

Our knowledge regarding immune-protective and immunopathogenic events in severe acute respiratory syndrome coronavirus (SARS-CoV) infection is limited, and little is known about the dynamics of the immune response at the primary site of disease. Here, an African green monkey (AGM) model was used to elucidate immune mechanisms that facilitate viral clearance but may also contribute to persistent lung inflammation following SARS-CoV infection. During primary infection, SARS-CoV replicated in the AGM lung for up to 10 days. Interestingly, lung inflammation was more prevalent following viral clearance, as leukocyte numbers peaked at 14 days postinfection (dpi) and remained elevated at 28 dpi compared to those of mock-infected controls. Lung macrophages but not dendritic cells were rapidly activated, and both cell types had high activation marker expression at late infection time points. Lung proinflammatory cytokines were induced at 1 to 14 dpi, but most returned to baseline by 28 dpi except interleukin 12 (IL-12) and gamma interferon. In SARS-CoV homologous rechallenge studies, 11 of the 12 animals were free of replicating virus at day 5 after rechallenge. However, incidence and severity of lung inflammation was not reduced despite the limited viral replication upon rechallenge. Evaluating the role of antibodies in immune protection or potentiation revealed a progressive increase in anti-SARS-CoV antibodies in lung and serum that did not correlate temporally or spatially with enhanced viral replication. This study represents one of the first comprehensive analyses of lung immunity, including changes in leukocyte populations, lung-specific cytokines, and antibody responses following SARS-CoV rechallenge in AGMs.
The influence of stochastic behavior on the human threshold of hearing

Abstract The inner hair cells in the cochlea perform the crucial task of transforming mechanical sound signals into electrical activity. The cochlear nerve fibers code this information and convey it to the brain for further processing. This study investigates the performance of the system inner hair cell – primary auditory afferent nerve fibers at the physical limit of the mechano-electrical transduction for the human auditory frequency range. The Brownian motion of the hair cell’s receptive organelle, the hair bundle, does not blunt the sensitivity, but in fact enlarges – especially in frequency regions which are most important for the perception of music and speech – via the mechanism of nonlinear stochastic resonance (SR) the dynamical range of the mechano-electrical transduction by at least one order of magnitude. The coding efficiency of small sinusoidal hair bundle deflections shows basic properties of the human hearing threshold curve for pure tones and corresponds to experimental results of noise-induced tuning curves in mechano-receptors in the rat foot. Furthermore, the model explains how altered coding efficiency contributes to pathological changes in the spiking pattern which arise from morphological changes in the hair bundle structure (e.g., in noise-induced sensorineural hearing loss of cochlear origin).
A mechanism for electric field effects observed in (RE)Ba2Cu3O7−x☆

Abstract The chain oxygen dynamics of (RE)Ba 2 Cu 3 O 7−x have been investigated using a Monte Carlo simulation of the asymmetric next nearest neighbor Ising (ASYNNNI) model. The effect of an electric field is to change the basal plane coordination of Cu ions, resulting in a change in the carrier doping of the CuO 2 planes. Our results from this model are in agreement with experiment and suggest a novel mechanism for the electric field effect.
Structural analysis of DNA cleaved in vivo by bacteriophage T4 terminase

Abstract Phage terminases are protein complexes that cleave concatemeric phage DNA and generate termini of the packaged DNA molecule. In phage T4, the DNA packaging proteins gpl6 and gpl7 are supposed to function as terminases. The recombinant T4 terminase proteins, upon expression in vivo from strong promoters, cleaved plasmid DNA in a sequence-independent manner. Resolution of the cleaved DNA by agarose-gel electrophoresis showed a smear throughout the lane including a fraction that was retained in the well [Bhattacharyya and Rao, Virology 196 (1993) 34–44]. The appearance of a smear in the high- M r region could not be explained solely on the basis of a simple random-cutting mechanism. Various hypotheses were tested to elucidate the structure of the high- M r DNA. The data show that the high- M r DNA did not arise either by attachment of protein (s) to DNA, or by covalent linkage of cleaved DNA molecules by a recombinational mechanism. It appears that the high- M r DNA arose as a result of non-covalent linkage of plasmid DNA through single strands. A working model for the action of T4 terminase is presented.
On the effect of an interfacial layer on the fracture behavior of interface and subinterface cracks in single-lap shear joints

Linear elastic fracture mechanics (LEFM), combined with a 2-D finite element analysis based on a p-version finite element code, PROBE, was applied to study interface and subinterface cracks in single-lap shear joints. The effects of the thickness and properties of interfacial layer on the fracture property of adhesive joints were examined. The results show that, in general, the stress intensity factors (SIFs) are strongly influenced by the ratio of the Young's modulus of the interfacial layer to that of the adhesive, but they are less sensitive to the thickness of the interfacial layer (within 0.01-0.03 mm). In addition, the longer the crack length, the larger the magnitude of the SIF, which shows an increasing crack driving force with crack length. Aside from the differences in the magnitude of SIFs and those in the variations of K2 and KII, where K2 and KII are the Mode II components of the interfacial and subinterfacial SIFs, respectively, the general trend of the variations of SIFs with respect to the...
SU‐GG‐T‐491: Dose Summation for Multi‐Phase Helical Tomotherapy Plans

Purpose: Develop a method to combine dose matrices from multi‐phase Tomotherapy plans to facilitate dose escalation clinical trials. Method and Materials: For many clinical sites it is customary to use treatment plans consisting of 2–3 phases. Currently the Tomotherapy treatment planning system doesn't provide a method to combine these phases, thus hampering the ability of clinicians to review dose volume information. We propose a simple method to create a composite plan which could be evaluated on a tertiary treatment planning system (TPS). Dose matrices from approved Tomotherapy plans for each phase are extracted and exported to a temporary location. A software algorithm was developed to read each distribution and perform a pixel by pixel summation. The final dose matrix was reviewed and placed in a format compatible with Pinnacle‐TPS. The dose matrix was then registered with the image set in Pinnacle facilitating composite plan evaluation. The accuracy of the method was tested using ion chamber and film measurements. Film dosimetry was performed using EBT‐Gafchromic film, Epson flatbed scanner and our in‐house film dosimetry protocol. The measured dose distributions were compared with values calculated by Tomotherapy at the location of the film and summed using this method. Dose distributions were compared using the γ‐index. Results: The x,y,z registration errors between the composite dose matrix and the image set of the TPS were found to be 0.6mm for x‐y axes and 1.5mm for z‐axis. Ion chamber measurements were within 1–2%. Good agreement (low gamma, high conformity index) was recorded using film dosimetryConclusion: This summation method provides a fast, accurate, and simple way to evaluate multiphase composite treatment plans. The method can be used to sum dose distributions provided by different treatment planning system or to perform dosimetric comparisons between plans from these systems.
Regulation of Pyruvate Metabolism in Rat-Liver Mitochondria by K+ and Pi

The regulation of pyruvate metabolism in isolated rat-liver mitochondria was studied in six media of varying ionic composition. In media containing low concentrations of Pi ( 40 mM), pyruvate was metabolized exclusively to acetoacetate. Similarly, low K+ concentrations (9 mM) stimulated formation of citrate and malate from pyruvate when the Pi concentration was low but not when it was high. Inclusion of malate, as a source of oxaloacetate, in media which did not permit pyruvate alone to be metabolized to citrate and malate, eliminated accumulation of acetoacetate and caused pyruvate to be metabolized to citrate exclusively. Thus, it is possible that high Pi concentrations or high K+ concentrations inhibited pyruvate carboxylase but not citrate synthase. The dietary state (fasted or fed) of the rat prior to death affected the absolute or relative activities of these two path ways of pyruvate metabolism.
Towards image-guided photodynamic therapy of Glioblastoma

Glioblastoma (GBM) is an aggressive cancer with dismal survival rates and few new treatment options. Fluorescence guided resection of GBM followed by photodynamic therapy (PDT) has shown promise in several chemo- or radiotherapy non-responsive GBM treatments clinically. PDT is an emerging light and photosensitizer (PS) mediated cytotoxic method. However, as with other therapeutic modalities, the outcomes are variable largely due to the nonpersonalization of dose parameters. The variability can be attributed to the differences in heterogeneous photosensitizer accumulation in tumors. Building upon our previous findings on utilizing PS fluorescence for designing tumor-specific PDT dose, we explore the use of photoacoustic imaging, a technique that provides contrast based on the tissue optical absorption properties, to obtain 3D information on the tumoral photosensitizer accumulation. The findings of this study will form the basis for customized photodynamic therapy for glioblastoma and have the potential to serve as a platform for treatment of other cancers.
Peacemaking criminology: etiology of crime or philosophy of life?

Over the last two decades, peacemaking criminology has become an increasingly influential perspective in crime and justice. This alternative view of criminology offers a unique outlook on how the justice system should attempt to view and ultimately deal with crime and punishment. Simply put, the peacemaking perspective presents a comprehensive blueprint of how principles and values of peace can be applied and used as a foundation of justice in a given society. However, one question still remains regarding the applicability of peacemaking criminology: is peacemaking a viable criminological theory or is it a philosophy for living one's life by? The goal of this paper is to provide an informed interpretation of the peacemaking perspective. First, the background and historical context of peacemaking as a philosophy will be discussed, calling specifically upon its religious and spiritual underpinnings. Next, early criminological theories that inspired peacemaking will be discussed in order to understand it as ...
A Single Catalytically Active Subunit in the Multimeric Sulfolobus shibatae CCA-adding Enzyme Can Carry Out All Three Steps of CCA Addition

The CCA-adding enzyme ATP(CTP):tRNA nucleotidyltransferase builds and repairs the 3′-terminal CCA sequence of tRNA. Although this unusual RNA polymerase has no nucleic acid template, it can construct the CCA sequence one nucleotide at a time using CTP and ATP as substrates. We found previously that tRNA does not translocate along the enzyme during CCA addition (Yue, D., Weiner, A. M., and Maizels, N. (1998) J. Biol. Chem. 273, 29693-29700) and that a single nucleotidyltransferase motif adds all three nucleotides (Shi, P.-Y., Maizels, N., and Weiner, A. M. (1998) EMBO J. 17, 3197-3206). Intriguingly, the CCA-adding enzyme from the archaeon Sulfolobus shibatae is a homodimer that forms a tetramer upon binding two tRNAs. We therefore asked whether the active form of the S. shibatae enzyme might have two quasi-equivalent active sites, one adding CTP and the other ATP. Using an intersubunit complementation approach, we demonstrate that the dimer is active and that a single catalytically active subunit can carry out all three steps of CCA addition. We also locate one UV light-induced tRNA cross-link on the enzyme structure and provide evidence suggesting the location of another. Our data rule out shuttling models in which the 3′-end of the tRNA shuttles from one quasi-equivalent active site to another, demonstrate that tRNA-induced tetramerization is not required for CCA addition, and support a role for the tail domain of the enzyme in tRNA binding.
On the impact rate and impact energy of particles in a slurry pot erosion tester

Abstract Short-time erosion tests were conducted with dilute water and water-glycerin suspensions of glass beads to determine the rate of particle impact and the dimensions of impact craters using annealed and electropolished OFHC copper rod specimens. Particle diameters were 75–90, 212–250, 500–600 and 750 μm, nominal rotation speeds of the erosion targets in the pot were 9.35 and 18.7 m s −1 and the carrier liquid viscosity was in the range (0.66–60) × 10 −3 N s m −2 , (0.66–60 cp). The work done in forming a crater of specified diameter was determined for each particle size by indentation using a single glass bead mounted on a microhardness tester. Using the assumption that all the kinetic energy of an impacting bead was dissipated in plastic work, the impact velocities of particles forming craters were calculated for most test conditions. The collision efficiency for the specimen was determined for most test conditions and was found to decrease with decreasing nominal velocity, increasing carrier liquid viscosity and decreasing particle size. The erosion rate, expressed as either material lost per unit area per unit mass of impacting particles or material lost per unit area per unit time, was estimated and shown to be strongly affected by the flow conditions for individual particles.
Picture the difference: electrophysiological investigations of picture processing in the two cerebral hemispheres.

Abstract The nature of semantic memory and the role of the two cerebral hemispheres in meaning processing were examined using event-related brain potentials (ERPs) elicited by pictures in sentences. Participants read sentence pairs ending with the lateralized presentation of three target types: (1) expected pictures, (2) unexpected pictures from the expected semantic category, and (3) unexpected pictures from an unexpected category. ERPs to contextually unexpected pictures were more negative 350–500 ms (larger N400s) than those to expected pictures in both visual fields. However, while N400s to the two types of unexpected items did not differ with left visual field presentations, they were smaller to the unexpected items from the expected category with right visual field presentations. This pattern, previously observed to words [Brain Language 62 (1998) 149], suggests general differences in how the two hemispheres use context on-line. Other aspects of the N400 response—and effects on earlier ERP components—reveal differences between pictures and words, suggesting that semantic memory access is not modality-independent. The P2 component varied with ending type for right but not left visual field presentations, suggesting that the left hemisphere may use contextual information to prepare for the visual analysis of upcoming stimuli. Furthermore, there was clear evidence for an earlier negativity (“N300”), which varied with ending type but, unlike the N400, was unaffected by visual field of presentation. Overall, the results support our hypothesis that the left hemisphere actively uses top–down information to preactivate perceptual and semantic features of upcoming stimuli, while the right hemisphere adopts a “wait and see” integrative approach.
Effects of Ddc cluster lethal alleles on ovary growth, attachment, and egg production in Drosophila

The Ddc cluster of genes on the left arm of chromosome 2 in Drosophila has been extensively characterized by Wright and coworkers (Wright, '87b). Many of the genes in the cluster are associated with the pigmentation and sclerotization of the cuticle, and at least 12 have been shown to play a role in female fertility. To characterize further the actions of genes in the cluster, we have investigated the effect on fertility of a total of five of the previously untested genes (l(2)37Be, Bb, Bg, Bd, and Cg), and three of the partially characterized genes (l(2)37Ce, Ddc, and amd). Each allele was crossed to Df(2L)TW130 or49h flies in order to make it hemizygous over the 8–12 band deficiency covering the Ddc region, 37B9-C1,2;37D1-2. Ovaries taken from larvae produced by this cross were transplanted into female larval hosts of y f mal genotype, that were then mated to v f mal males. The wild type allele of mal in implanted tissue allowed identification and study of surviving implants by staining for the presence of aldehyde oxidase. Of the 18 alleles available, amdH149, l(2)37Bb1, Bb9, Bb11, Bd6, Be1, Bd7, Be2, Be3, Ce4, and Cg1 did not allow enough growth to form transplantable ovaries; l(2)37Bg1, Bg2, and Cgtsl prevented development of transplanted ovaries in their hosts; l(2)37Ce5 allowed implanted ovaries to attach to oviducts and grow, but insufficiently for production of eggs; and DdcN27, amd29, and l(2)37Bd4 appeared not to restrict ovary development. Heteroallelic heterozygotes of Bd7 × Bd4 also produced fully fertile ovaries, but no other heteroallelic combinations did so. No obvious correlation exists between this pattern of effects on ovarian fertility and the overall organization of the gene cluster. © 1994 Wiley-Liss, Inc.