cssi/SciSciGPT-SciSciNet huggingface dataset:
"I'm Khmer and I'm not a gangster!": The problematization of Cambodian male youth in US schools

In response to a literature that has paid limited attention to the complex representations of Cambodian students, this article investigated the ways in which Cambodian male youth were problematized in school through Discourses that presented them as apathetic students and/or gang members at one California high school. In this study, the ways in which race, gender, and class collided in the school experiences of Cambodian boys manifested themselves in troubling representations that deflected attention away from the school’s failure to teach these young men. For these negative representations to work, it was necessary to position Cambodian boys in contrast to more positive depictions of other students’ racial (whites and “East Asians”), class (non-“ghetto”), and gender (good Cambodian girls) categories. Overall, this study contributes an important dimension for understanding the education of Asian American urban male students, particularly Cambodian youth.
On algebraic compilers and planetary fly-by orbits

Abstract This paper reports on two major technology events of great significance in the field of Astronautics which were conceived and developed at the MIT Instrumentation Laboratory during the decade of the fifties. It is a personal memoir by the author on two important topics which should be a part of the written history of our field. Part one details the conception and development by Dr J. Halcombe Laning, Jr of “George”, the world's first algebraic compiler for use on Project Whirlwind—MIT's first experimental all-digital computer. This was indeed challenging since Whirlwind at that time had but 1024 sixteen-bit words. Dr Laning began work in the summer of 1952 and the first version of the George compiler was finished in March of 1953. In the early fifties many people were debating the feasibility of a system for translating algebraic formulae into computer programs which would allow the engineer to avoid the all too painstaking and error-prone task of writing programs using basic computer code. But Hal Laning was the first to do it. In part two of this paper, the author explores the early concepts of energy exchange between a spacecraft and a planet during a close encounter of these two celestial objects. The fact that this energy transfer could be exploited for useful purposes in the development of interplanetary orbits was first documented in an MIT Instrumentation Laboratory report published in April of 1958. The topic has been the subject of recent papers at several IAF congresses, but they failed to recognize the early work at MIT. As a part of this important history, the author describes his own work to develop a round-trip orbit to Mars using the planet Venus for a gravity assist to shorten the flight time from three years to one and a quarter years. The first orbit of this type was obtained by the author on 26 January 1961. To the author's knowledge, no one has even suggested that practical three-dimensional multiple fly-by orbits had been constructed at an earlier date.
Using raman spectroscopy to characterize bone metastasis and to evaluate treatment response in prostate cancer patients

Raman spectroscopy was applied in this study to investigate the structure and composition of metastatic bone from prostate patients. The ultimate goal is to identify spectral features related to cancer and treatment induced bone changes.
Joint blind source separation: Applications in medical image analysis

Blind source separation (BSS) is based on a simple generative model and hence minimizes the assumptions on the nature of data. It provides a promising alternative to the traditional model-based approaches in many applications where the underlying dynamics are hard to characterize. Independent component analysis (ICA), in particular, has been a popular BSS approach and an active area of research. By imposing the constraint of statistical independence on the underlying components, ICA recovers linearly mixed components subject to only a scaling and permutation ambiguity, and has been successfully applied to numerous problems in areas as diverse as biomedicine, communications, finance, geophysics, and remote sensing.
Phase behavior of the 38-atom Lennard-Jones cluster

We have developed a coarse-grained description of the phase behavior of the isolated 38-atom Lennard-Jones cluster (LJ38). The model captures both the solid-solid polymorphic transitions at low temperatures and the complex cluster breakup and melting transitions at higher temperatures. For this coarse model development, we employ the manifold learning technique of diffusion mapping. The outcome of the diffusion mapping analysis over a broad temperature range indicates that two order parameters are sufficient to describe the cluster's phase behavior; we have chosen two such appropriate order parameters that are metrics of condensation and overall crystallinity. In this well-justified coarse-variable space, we calculate the cluster's free energy landscape (FEL) as a function of temperature, employing Monte Carlo umbrella sampling. These FELs are used to quantify the phase behavior and onsets of phase transitions of the LJ38 cluster.
On the numerical computation of orbits of dynamical systems: The one-dimensional case

A finite time version of the shadowing theorem is used to develop a procedure to determine the accuracy of numerically computed orbits of one-dimensional maps. The procedure works forward. After any given number of iterates, we can decide whether our theorem applies and, if it does, we can estimate how far the computed orbit is from a true orbit.
Accurate Linear Bidirectional Diode Gates

In a computer developed at the Columbia University Electronics Research Laboratories, it was necessary to design a network having the following properties: Its transfer function should be determined by an audio-frequency square-wave control voltage, the transfer function should be unity for one polarity of the square wave and zero for the other polarity, and the inaccuracies should be less than 0.1 per cent. This paper describes two-diode, four-diode, and six-diode types of bridge switches which were investigated to meet the above need. For each type a discussion is given of the important parameters of the system such as control voltage amplitudes, magnitude of gain, constancy of gain versus signal amplitude, leakage through the back resistances of the diodes, effects of unbalances in the system, and others. A brief review is given of triode and pentode gates. A discussion is also given of the considerations arising from the use of series, parallel, and series-parallel combinations of switches. Some actual circuits are described which meet the original specifications. An experimental method for checking the linearity is given.
Translation by Single Ribosomes Through mRNA Secondary Structures

During protein synthesis, the ribosome moves along a single mRNA strand and translates the genetic code into polypeptide sequences. Strong mRNA secondary structures, which have to be unfolded in order to be translated, can slow or even halt protein synthesis. Pseudo-knots (PKs), mRNA secondary structures containing at least two stem-loops, are essential elements in programmed ribosomal frameshifting, for instance, during translation of some viral mRNAs. Here we employ single molecule fluorescence resonance energy transfer (smFRET) to determine reaction rates for specific polypeptide elongation cycles as the ribosome encounters a minimal viral PK structure during mRNA translation. An elongation cycle may be divided into three steps: 1) aminoacyl-tRNA binding to the A-site, 2) translocation of the bound mRNA and tRNAs from the A- and P- sites to the P- and E-sites, and 3) dissociation of deacylated tRNA from the E-site. We use FRET interactions between i) adjacent ribosome-bound tRNAs, ii) aminoacyl-tRNA and ribosomal protein L11 at the A-site, and iii) deacylated tRNA and ribosomal protein L1 at the E-site, to determine the rates of steps 1) - 3) during elongation cycles of ribosomes programmed with mRNAs either containing or lacking a PK. We find that, whereas the presence of a PK has little or no effect on the rates of steps 1) and 2), it strongly decreases (∼2.5-fold) the rate of step 3. Thus, somewhat surprisingly, step 3) appears to be more strongly coupled to the unfolding of PK structure than step 2). In contrast, preliminary results indicate that stem-loop structures can decrease the rates of both steps 2) and 3). Supported by NIH grant R01GM080376.
Current and emerging therapies for metastatic colorectal cancer: applying research findings to clinical practice.

Purpose. The results of clinical trials that led to modern first- and second-line chemotherapeutic regimens for metastatic colorectal cancer, including studies of recently introduced monoclonal antibody products that target vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR), are described, as well as new therapeutic targets being studied and challenges in research to identify and evaluate new therapies. Summary. Modern chemotherapy regimens for first-line treatment of metastatic colorectal cancer contain fluorouracil, leucovorin, either oxaliplatin or irinotecan, and the VEGF inhibitor bevacizumab. The EGFR inhibitors cetuximab and panitumumab currently are reserved for second- or third-line therapy, but their role could change as the results of clinical research become available. The phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin pathway, src kinases, and insulin-like growth factor-1 receptor are among the targets of current research. Identifying the subset of patients with metastatic colorectal cancer who stand to benefit from a particular therapy presents a challenge in conducting clinical research. Conclusion. Modern chemotherapeutic and monoclonal antibody regimens have improved survival in patients with meta-static colorectal cancer. The optimal combinations, timing, and sequence of agents remain to be determined.
Reflective optical sensor system for measurement of intracranial pressure

This paper describes a novel optical fiber intracranial pressure (ICP) sensor system that uses a reflective fiber optic displacement sensor to measure hydrostatic pressure. A reference reflection from a mirror incorporated into the fiber is used in signal processing to eliminate the effects of power fluctuations, loss in connector, and splices in the fiber. This sensing technique exhibits a high degree of sensitivity and linearity, and is less susceptible to environmental perturbations than current intensity modulating techniques. Experimental results are presented for measurements taken with and without an anti-reflection (AR) coating on the fiber tip facing the sensor mirror. These measurements indicate an improved dynamic range of operation for this sensor.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Effective stylus diameter determination using near zero-width reference

A gage for low uncertainty determination of the effective diameter of styli used for probing in coordinate measuring machines is presented here. The gage embodies a near-zero width reference line which can be measured from opposing sides to obtain the effective stylus diameter. Two modified gage blocks are utilized in the construction of this artifact.
Methyl halide emissions from greenhouse-grown mangroves

[1] Two mangrove species, Avicennia germinans and Rhizophora mangle, were greenhouse grown for nearly 1.5 years from saplings. A single individual of each species was monitored for the emission of methyl halides from aerial tissue. During the first 240 days, salinity was incrementally increased with the addition of seawater, and was maintained between 18 and 28‰ for the duration of the study. Exponential growth occurred after 180 days. Methyl halide emissions normalized to leaf area were measured throughout the study and varied dramatically. Emission rates normalized to land area (mg m−2 y−1), assuming a LAI = 5, yielded 82 and 29 for CH3Cl, 10 and 1.6 for CH3Br, and 26 and 11 for CH3I, for A. germinans and R. mangle, respectively. From these preliminary determinations, only CH3I emissions emerge as being of possible global atmospheric significance. This study emphasizes the need for field studies of methyl halide emissions from mangrove forests.
Traffic characteristics of a distributed memory system

Abstract We believe that many distributed computing systems of the future will use distributed shared memory as a technique for interprocess communication. Thus, traffic generated by memory requests will be a major component of the traffic for any networks which connect nodes in such a system. In this paper, we study memory reference strings gathered with a tracing program we devised. We study several models. First, we look at raw reference data, as would be seen if the network were a backplane. Second, we examine references in units of “blocks”, first using a one-block cache model and then with an infinite cache. Finally, we study the effect of predictive prepaging of these “blocks” on the traffic. We provide a novel representation of memory reference data which can used to calculate interarrival distributions directly. Integrating communication with computation can be used to control both traffic and performance.
Framing and strategy : explaining differential longevity in the Woman's Christian Temperance Union and the Anti-Saloon League

This study examines the sources of strength and mobilizing impetus in the Anti-Saloon League (ASL) and the Woman's Christian Temperance Union (WCTU) in the early twentieth century. Both the ASL and the WCTU played essential roles in the establishment of national prohibition. The quick demise of the ASL after the repeal of the Eighteenth Amendment in 1933 and the endurance of the WCTU cannot be explained only by the structural conditions that confronted the two movements, as suggested by the resource mobilization approach. Using Snow and Benford's “collective action frame” concept, it is argued that a consideration of meanings constructed by the movements’leaders and their translation into strategic action provides a better account of the temporal viability of the WCTU and ASL. The critical distinction between the WCTU and ASL was in how they framed the “alcohol question.” Both the relative success of the WCTU and the failure of the ASL were contingent upon their ability to adapt their rhetoric and corresponding strategies to rapid shifts in the cultural and economic climate of the late twenties and early thirties.
A Comparison of Cerebral SPECT Abnormalities in HIV-Positive Homosexual Men With and Without Cognitive Impairment

Objective: To determine whether technetium Tc 99m exametazime (HMPAO) single-photon emission computed tomography (SPECT) can distinguish between human immunodeficiency virus (HIV)-positive homosexual men with normal neuropsychologic test results and HIV-positive homosexual men with abnormal neuropsychologic test results. Design: Neurologic, neuropsychologic, magnetic resonance imaging, and Tc 99m HMPAO SPECT examinations were performed on 10 HIV-positive homosexual men without cognitive impairment and five HIV-positive homosexual men with cognitive impairment. Patients: Human immunodeficiency virus—positive homosexual men from New York City were recruited for the study. Main Outcome Measures: Findings on SPECT scans were evaluated qualitatively for focal defects, heterogeneity of the cortical margin, white matter hypoperfusion, and decreased global cortical uptake. All SPECT focal defects were coregistered with magnetic resonance images; SPECT heterogeneity and global cortical uptake were also measured quantitatively. Results: Coregistration with magnetic resonance imaging revealed that 63% of the focal SPECT defects corresponded to brain gyri and 37% corresponded to sulci. There was no significant difference in the frequency of qualitative or quantitative SPECT abnormalities between HIV-positive homosexual men with and without cognitive impairment. However, after examining individual neuropsychologic test factors, impaired motor speed performance was associated with decreased quantitative global cerebral uptake. Conclusions: Qualitative SPECT abnormalities are not increased in frequency in HIV-positive homosexual men with global cognitive impairment compared with those in HIV-positive homosexual men without cognitive impairment. Impaired motor speed performance may be associated with decreased quantitative global cerebral uptake.
A selective spatial discrimination deficit after fornicotomy in the rat.

Fifteen fornix-lesioned and 15 sham-operated albino rats were trained in a plus (+)-shaped maze, for food reinforcement, to run to a specific goal arm (position discrimination groups) or to make a specific turn (response discrimination groups). Acquisition and five successive reversals of the discrimination were run. Fornix lesions produced a selective impairment in the acquisition and reversal performance of the position discrimination. The response discrimination was not affected by the lesion. The results were interpreted to indicate that the hippocampal-fornix system is implicated in the long-term storage or retrieval of the spatiotemporal relationships of stimuli in the environment.
Peroral endoscopic myotomy periprocedural evaluation: Predicting and measuring outcomes ☆

Peroral endoscopic myotomy (POEM) is a novel endoscopic operation for achalasia that creates a controlled myotomy across the esophagogastric junction, while offering the potential of reduced pain and convalescence when compared with laparoscopic Heller myotomy. However, the long-term efficacy of the procedure is yet to be determined. This article describes the symptom measures and tests of esophagogastric junction physiology that can be used to evaluate patients before, during, and after the POEM procedure. The Eckardt score and other quantitative symptom measures are discussed, as are physiological and diagnostic tests including high-resolution manometry, timed barium esophagram, upper endoscopy, functional lumen imaging probe, and pH monitoring. In combination, these metrics are essential in establishing the diagnosis of achalasia, choosing a treatment modality and predicting its efficacy, and evaluating outcomes after surgery. Additionally, the results of these quantitative evaluations serve as important research data to evaluate the long-term efficacy of POEM and compare it with the current standards of care, laparoscopic Heller myotomy and endoscopic pneumatic dilation.
Role of Psychologists in Academic Medicine

With an interdisciplinary approach to understanding human psychosocial development and behavior, psychologists in academic medical settings have much to offer in the areas of administration, research, teaching, and service, including in the realm of organizational systems and behavior within medical schools. In these ways, psychologists can play a large role in the fulfillment of the mission of academic medicine and enhance psychology’s stature in the medical school organization. Two case studies are presented that exemplify the varied roles and responsibilities of psychologists in a medical school. To be successful within medical schools, the following generalizable principles are offered: (1) “add value” to the medical school by demonstrating the diverse and relatively unique abilities of psychologists; (2) be flexible and adaptive to the different requirements of medical academic settings; (3) make a concerted effort to work well with medical students, residents, and physicians who may not be well-versed in certain aspects such as rigorous research methodology and statistics; and (4) find a “good match” between one’s strengths, the needs of the medical setting, and the attributes of the M.D. leader. With such an approach, remarkable accomplishments can be made.
Femtosecond exciton dynamics in DOO-PPV films

We studied the ultrafast exciton dynamics in DOO-PPV films using the technique of femtosecond photoinduced absorption decay. We found that the exciton dynamics contains an ultrafast decay component of about 2 ps that remains unchanged at intensities up to five times the threshold excitation intensity for the phenomenon of emission spectral narrowing. We argue that amplified spontaneous emission of waveguided or leaky modes, depending on film thickness and excitation geometry, is the dominant mechanism for both spectral narrowing and ultrafast decay component. In very thin films we found that the process of amplification of leaky waves may be responsible for the amplification of the 0-0 emission band rather than the 0-1 band, that has been usually observed at high excitation intensities in thicker films.
TOPOISOMERASE II SITE-DIRECTED ALKYLATION OF DNA BY PSOROSPERMIN AND ITS EFFECT ON TOPOISOMERASE II-MEDIATED DNA CLEAVAGE

Psorospermin, a plant-derived antitumor agent, has been shown to selectively alkylate a guanine at the topoisomerase II cleavage site to trap the topoisomerase II-DNA cleaved complex. The results of this study provide further important insight into the mechanism of the topoisomerase II site-directed alkylation of DNA by psorospermin and its subsequent effects on the topoisomerase II-induced DNA cleavage. First, we demonstrate that the topoisomerase II-induced alkylation of DNA by psorospermin occurs at a time preceding the topoisomerase II-mediated strand cleavage event, because it occurs in the absence of Mg2+. We confirm that the alkylation of DNA by psorospermin takes place at N-7 of guanine in the presence of topoisomerase II, because substitution of the target guanine by 7-deazaguanine prevents alkylation. Because the stimulation of the topoisomerase II-induced DNA cleavage by psorospermin can be slowly reversed by the addition of excess salt, this indicates that alkylation of DNA by psorospermin traps a reversible topoisomerase II-DNA complex. Both the DNA alkylation by psorospermin in the presence of topoisomerase II and the enzyme-mediated DNA cleavage elevated by psorospermin are more enhanced at acidic pH values, in accordance with the increased stability of the topoisomerase II-DNA complex at acidic pH values. Finally, our results suggest that it is the psorospermin-DNA adducts, not the abasic sites resulting from depurination, that are responsible for the stimulation of the topoisomerase II-mediated cleavage. Because the precise location of the psorospermin within the topoisomerase II cleavage site is known, together with the covalent DNA linkage chemistry and the conformation of the psorospermin-DNA adduct, this structural insight provides an excellent opportunity for the design and synthesis of new, more effective topoisomerase II poisons.
The GPIIb/IIIa (integrin αIIbβ3) odyssey: a technology-driven saga of a receptor with twists, turns, and even a bend

Starting 90 years ago with a clinical description by Glanzmann of a bleeding disorder associated with a defect in platelet function, technologic advances helped investigators identify the defect as a mutation(s) in the integrin family receptor, αIIbβ3, which has the capacity to bind fibrinogen (and other ligands) and support platelet-platelet interactions (aggregation). The receptor's activation state was found to be under exquisite control, with activators, inhibitors, and elaborate inside-out signaling mechanisms controlling its conformation. Structural biology has produced high-resolution images defining the ligand binding site at the atomic level. Research on αIIbβ3 has been bidirectional, with basic insights resulting in improved Glanzmann thrombasthenia carrier detection and prenatal diagnosis, assays to identify single nucleotide polymorphisms responsible for alloimmune neonatal thrombocytopenia, and the development of αIIbβ3 antagonists, the first rationally designed antiplatelet agents, to prevent and treat thrombotic cardiovascular disease. The future looks equally bright, with the potential for improved drugs and the application of gene therapy and stem cell biology to address the genetic abnormalities. The αIIbβ3 saga serves as a paradigm of rigorous science growing out of careful clinical observations of a rare disorder yielding both important new scientific information and improved diagnosis, therapy, and prevention of other disorders.
Diagnosis and Management of Behavioral Variant Frontotemporal Dementia

Frontotemporal dementia was documented over a century ago. The last decade, however, has seen substantial changes in our conceptions of this increasingly recognized disorder. Different clinical variants have been delineated, the most common of which is the behavioral variant (bvFTD). Updated diagnostic criteria have been established. New histopathological findings and genetic etiologies have been discovered. Research continues to uncover molecular mechanisms by which abnormal proteins accumulate in degenerating brain tissue. Novel neuroimaging techniques suggest that functional networks are diminished in bvFTD that might be relevant to empathy and social behavior. Despite rapid advances in our understanding of bvFTD, the disease is still under-recognized and commonly misdiagnosed. The result is inappropriate patient care. Recognizing the various presentations of bvFTD and its histological and genetic subtypes might further diagnosis, treatment, and research.
Forty years of periodic vehicle routing

The periodic vehicle routing problem PVRP first appeared in 1974 in a paper about garbage collection Beltrami and Bodin, Networks 4 1974, 65-74. The wide applicability and versatility of the problem has led to a vast body of literature addressing both novel applications and solution methods. This article discusses the wide array of circumstances and settings in which the PVRP has been applied and describes the development of solution methods, both exact and heuristic, for the PVRP. As with many core research problems, many variants have been proposed. We will describe additional problem variants and extensions, as well as discuss the future of research for the PVRP. © 2013 Wiley Periodicals, Inc. NETWORKS, Vol. 631, 2-15 2014
Effect of Injection Parameters and Strategy on the Noise From a Single Cylinder Direct Injection Diesel Engine

Acoustic noise emitted by a diesel engine generally exceeds that produced by its spark-ignited equivalent and may hinder the acceptance of this more efficient engine type in the passenger car market (1). This work characterizes the combustion noise from a single-cylinder direct-injection diesel engine and examines the degree to which it may be minimized by optimal choice of injection parameters. The relative contribution of motoring, combustion and resonance components to overall engine noise are determined by decomposition of in-cylinder pressure traces over a range of load, injection pressure and start of injection. The frequency spectra of microphone signals recorded external to the engine are correlated with those of in-cylinder pressure traces. Short Time Fourier Transformation (STFT) is applied to cylinder pressure traces to reveal the occurrence of motoring, combustion noise and resonance in the frequency domain over the course of the engine cycle. Loudness is found to increase with enhanced resonance, in proportion to the rate of cylinder pressure rise and under conditions of high injection pressure, load and advanced injection timing.Copyright © 2011 by ASME
The Question of Voice and the Limits of Pragmatism: Emerson, Dewey, and Cavell

: One criticism of pragmatism, forcefully articulated by Stanley Cavell, is that pragmatism fails to deal with mourning, understood in the psychoanalytic sense as grief-work (Trauerarbeit). Such work would seemingly be as pertinent to philosophical investigations (especially ones conducted by pragmatists) as to psychoanalytic explorations. Finding such themes as mourning and loss in R. W. Emerson's writings, Cavell warns against assimilating Emerson's voice to that of American pragmatism, especially Dewey's instrumentalism, for such assimilation risks the loss or repression of Emerson's voice in not only professional philosophy but also American culture. While granting Emerson's distinctive voice, this essay argues that the way Cavell insists on differences problematically represses recognition of the Emersonian strains in Dewey's own philosophical voice. In doing so, Cavell falsely flattens the resounding depth of Dewey's philosophical voice and narrows the expansive range of pragmatic intelligence. But Dewey all too often lends himself to such a misreading, for his writings at once repress and embody the strains of a distinctively Emersonian voice.
The supernormal phase of ventricular excitation in man. Its bearing on the genesis of ventricular premature systoles, and a note on atrioventricular conduction

Abstract Artificially produced ventricular premature beats apparently due to a supernormal phase of ventricular excitation in man is demonstrated. This phase occurs within 0.04 second of the beginning of the descent of the T wave. Subthreshold stimuli can produce parasystole with constant coupling and may explain some hitherto obscure A-V arrhythmias.
Depression-Related Negative Cognition: Mood-State and Trait Dependent Properties

This study tested the state-trait model of negative cognition (D. C. Zuroff, S. J. Blatt, C. A. Sanislow, C. M. Bondi, & P. A. Pilkonis, 1999) among people who were hospitalized for depression (N = 121). Assessments of cognitive bias, dysfunctional attitudes, and depression severity were completed during psychiatric hospitalization, following a 6-month course of outpatient treatment, and 1 year after completion of outpatient treatment. Mean-score change, test–retest correlation, and path analysis examined whether dysfunctional attitudes and cognitive bias were influenced by fluctuations in mood-state while also demonstrating relative stability over time. Results indicated that concurrent depression severity and prior level of negative cognition both uniquely influenced level of dysfunctional attitudes and cognitive bias during treatment and follow-up periods. As predicted by the state-trait model, negative cognition had dynamic, mood-state dependent properties, as well as stable, trait-like attributes.
Negative Relational Schemas Predict the Trajectory of Coercive Dynamics During Early Childhood

Coercive family processes are germane to the development of problem behaviors in early childhood, yet the cognitive and affective underpinnings are not well understood. We hypothesized that one antecedent of early coercive interactions is the caregiver’s implicit affective attitudes toward the child, which in this article are termed relational schemas. Relational schemas have previously been linked to coercion and problem behaviors, but there has yet to be an examination of the association between relational schemas and trajectories of coercion during early childhood. We examined 731 indigent caregiver-child dyads (49 % female children) from a randomized intervention trial of the Family Check-Up. Predominantly biological mothers participated. A speech sample was used to assess relational schemas at age 2. Coercive interactions were assessed observationally each year between ages 2 and 4. Caregiver and teacher reports of children’s oppositional and aggressive behaviors were collected at age 7.5 and 8.5. Path analysis revealed that negative relational schemas were associated with less steep declines in coercion during this period, which in turn were predictive of ratings of oppositional and aggressive behaviors at age 7.5/8.5 after controlling for baseline levels, positive relational schemas, child gender, ethnicity, and cumulative risk. Intervention condition assignment did not moderate this relationship, suggesting the results represent a naturally occurring process. Given the link between persistent early coercion and later deleterious outcomes, relational schemas that maintain and amplify coercive dynamics represent a potential target for early intervention programs designed to improve parent–child relationships.
Frequency Discrimination vs Frequency Estimation: Adult Age Differences and the Effect of Divided Attention

In this experiment we explored age differences in frequency judgment. Young and older adults studied words occurring from one to six times under divided or focused attention and then completed either a frequency discrimination or a frequency estimation test for these items. Divided attention led to poorer performance on both frequency judgment tests, suggesting that distraction during the encoding of target events results in less optimal encoding of the information that is necessary for any type of frequency judgment. Contrary to the notion that older adults encode this information more superficially than young adults, older adults were as sensitive as young adults to relative differences in the frequency of target words, and distraction did not magnify age differences for either type of frequency judgment task. On the other hand, older adults were less accurate in assigning an absolute numerical value to the frequency of the target words. Altogether, the results are consistent with the idea that'the encoding and/or retrieval processes required for accurate numerical estimation of frequency suffer a larger age-related decline than do those required for accurate discrimination of relative frequency.
An electromagnetic model for evaluating temporal water content distribution and movement in cyclically soaked mortar

Evaluation of water distribution and its temporal movement in cement-based materials is important for assessing cement hydration, curing, and long-term performance. From a practical standpoint, it is also important to obtain this information nondestructively. Near-field microwave nondestructive evaluation methods have proven effective for evaluation of cement-based materials for their various mixture properties, including the detection of salt added to the mixing water and chloride ions entering these materials through exposure to salt water solutions. Electromagnetic modeling of the interaction of microwave signals with moist cement-based materials can provide the necessary insight to evaluate water content distribution and movement in these materials. To this end, the temporal microwave reflection properties of a mortar cube, subjected to cycles of wetting and drying, were measured at 3 and 10 GHz using open-ended rectangular waveguides for several cycles, each lasting about 35 days. A semiempirical electromagnetic model, based on modeling the cube as a layered structure with each layer having a different dielectric constant, was then developed to simulate the measured reflection properties. The simulated and measured results were obtained for both frequencies and, for all cycles, were in good agreement. The most important outcome of the model is the temporal behavior of water content distribution and, hence, its movement in the mortar cube. This paper presents a brief description of the measurement approach and a detailed description of the model. A detailed discussion of the results and its sensitivity to various parameters is also provided.
Effects of Beetle Density and Time of Day on the Dispersal of Gratiana boliviana (Coleoptera: Chrysomelidae)

The leaf beetle, Gratiana boliviana Spaeth, is a biological control agent of tropical soda apple (Solanum viarum Dunal), a noxious weed invading the rangeland and agricultural fields of Florida and other southeastern states. In caged experiments, we examined the influence of beetle density and the time of day on the dispersal of the leaf beetle. Increasing beetle density from 2 to 100 beetles per plant did not increase G. boliviana dispersal, as long as the host plants were not severely defoliated. An increase in beetle density from 10 to 100 beetles per plant significantly reduced the per capita fecundity from 0.3 to 0.02 eggs over a 24-h period. Thus, a mass rearing method for G. boliviana should consider the potential detrimental effect of increasing density on the fecundity of the leaf beetle. When the dispersal activity of the leaf beetle was observed between 8:00 and 18:00 h, the proportion of beetles dispersing from a given plant increased throughout the morning hours and peaked at noon. A monitoring or sampling program of G. boliviana should be conducted in the early morning or late afternoon when the beetles' tendency to disperse is the lowest in order to more accurately sample for the population density in a certain area. Beetle density and the time of day interacted to influence the proportion of G. boliviana dispersing from a given plant. The proportions of beetles that dispersed were not different among the different time periods at densities of less than 40 beetles per plant. At or above 40 beetles per plant, the proportion of beetles that dispersed peaked at noon. This study suggests that a myriad of factors, including density, feeding damage, photoperiod and host plant quality, interact to determine the dispersal pattern of G. boliviana.
Latina/O Whitening? Which Latina/os self-classify as white and report being perceived as white by other Americans?

Some scholars argue that Latina/os in the United States may soon become White, much like the supposed Whitening of Eastern European immigrant groups in the early twentieth century. High rates of White racial identification on surveys among Latina/os is one explanation provided for this assertion. However, personal identification is but one element of racial boundary maintenance. It is when personal identification is externally validated that it is most closely associated with group-based experiences. This article maps components of the White-Latino racial boundary that may be permeable to White expansion by examining conditions under which Latina/os self-identify as White and report that they are externally classified as White by other Americans. Employing novel data from the 2006 Portraits of American Life Study, this article shows that nearly 40% of Latina/os sometimes self-identify as White, yet a much smaller proportion—only 6%—report being externally classified as White by others. Moreover, logistic regression analyses suggest that for those with light phenotypical features and high levels of socioeconomic status, the odds of reported external Whitening are increased. Interestingly, phenotypically light Latina/os with low-socioeconomic-status levels have low probabilities of reporting external classification as White when compared to their phenotypically light and high-socioeconomic-status counterparts, suggesting that the combination of both skin color and class may be central to the White-Latino racial boundary. Results also indicate that many who report external Whitening do not prefer to self-identify as White. In sum, multidimensional measures of racial classification indicate that only a very small minority of Latina/os may be “becoming White” in ways that some previous researchers have predicted.
Validation of theoretical framework explaining active solute uptake in dynamically loaded porous media

Solute transport in biological tissues is a fundamental process necessary for cell metabolism. In connective soft tissues, such as articular cartilage, cells are embedded within a dense extracellular matrix that hinders the transport of solutes. However, according to a recent theoretical study (Mauck et al., 2003, J. Biomech. Eng. 125, 602–614), the convective motion of a dynamically loaded porous solid matrix can also impart momentum to solutes, pumping them into the tissue and giving rise to concentrations which exceed those achived under passive diffusion alone. In this study, the theoretical predictions of this model are verified against experimental measurements. The mechanical and transport properties of an agarose–dextran model system were characterized from independent measurements and substituted into the theory to predict solute uptake or desorption under dynamic mechanical loading for various agarose concentrations and dextran molecular weights, as well as different boundary and initial conditions. In every tested case, agreement was observed between experiments and theoretical predictions as assessed by coefficients of determination ranging from R2=0.61 to 0.95. These results provide strong support for the hypothesis that dynamic loading of a deformable porous tissue can produce active transport of solutes via a pumping mechanisms mediated by momentum exchange between the solute and solid matrix.
Isolation and characterization of plasma membrane fractions from garfish Lepisosteus osseus olfactory nerve.

Garfish Lepisosteus osseus olfactory nerve, because of its large size and the unusually high concentration of axonal membrane, is an excellent source of axonal membrane. A procedure is described for the isolation of two types of plasma membranes from the nerve which are obtained in yields of about 20 mg (fraction I) and 1.5 mg (fraction II) per g of wet nerve. Both membrane fractions consist mostly of rounded membrane vesicles, with a unit membrane thickness of ∼7.5 nm. The two membrane fractions are different in their lipid to protein ratios, Na-K ATPase activities, polypeptide patterns on sodium dodecyl sulfate (SDS) gel electrophoresis, and fatty acid compositions. They have similar phospholipid composition. On the basis of the relative concentration of axonal and Schwann cell plasma membranes in the nerve, the Na-K ATPase activities of the two membrane fractions and a comparison of the properties of the membrane fractions to those of squid and lobster nerve membrane preparations, fraction I seems to be the axonal membrane and fraction II the Schwann cell plasma membrane. Fraction I has a low protein to lipid ratio. Its polypeptide pattern on SDS gel appears to be much more complex as compared to that of fraction II membrane.
Carcinogenic and inflammatory effects of plutonium-nitrate retention in an exposed nuclear worker and beagle dogs.

AbstractPurpose: Plutonium-nitrate has a moderately rapid translocation rate from the lung to blood stream. Previous studies have shown an unexpected retention of soluble plutonium in the beagles and human case studied here. The inflammatory responses that may be associated with long-term exposure to ionizing radiation were characterized. These pathways include tissue injury, apoptosis, and gene expression modifications. Other protein modifications related to carcinogenesis and inflammation and the various factors that may play a role in orchestrating complex interactions which influence tissue integrity following irradiation were investigated.Materials and methods: We have examined numerous lung samples from a plutonium-exposed worker, a human control, and a variety of plutonium-exposed beagle dogs using immunohistochemistry and quantitative Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR).Results: The exposed human showed interstitial fibrosis in peripheral regions of the lung, but no pulmonary ...
Perceptions of Effectiveness Among College Students: Toward Marriage and Family Counseling and Therapy

Unlike perceptions toward professional counseling, public opinions do not typically associate marriage and family counseling or therapy with treatments of mental disorders. The current survey of college students in this sample confirmed that most would not recommend, specifically, marriage and family therapists (MFTs) for mental health evaluations, psychiatric symptoms, intelligence and personality assessments, drug abuses, among others. The only situation for which students would most recommend an MFT is issues pertaining to marriage and the family. Implications for professional promotion and credentialing include enhancing the visibility, availability, and qualifications of marriage and family counselors (MFCs) or therapists especially through educational venues such as schools as well as media outlets.
Calibration of System Parameters Under Model Uncertainty

This paper investigates the quantification of errors and uncertainty in Bayesian calibration of structural dynamics computational models, affected by choices in model fidelity. Since Bayesian calibration uses an MCMC approach for sampling the updated distributions, using a high-fidelity model for calibration can be prohibitively expensive. On the other hand, use of a low-fidelity model could lead to significant error in calibration and prediction. This paper investigates model parameter calibration with a low-fidelity model corrected using higher fidelity simulations, and the trade-off between accuracy and computational effort. Different fidelity models may have different mesh resolutions, physics assumptions, boundary conditions, etc. The application problem used is of a curved panel located in the vicinity of a hypersonic aircraft engine, subjected to acoustic, thermal and aerodynamic loads. Two models are used to calibrate the damping characteristics of the panel: frequency response analysis and full time history analysis, and the trade-off between accuracy and computational effort is examined.
Renewable Energy: Ready to Meet Its Promise?

Research has brought the promise of renewable energy closer to fruition. Renewable resources can now be harnessed with enough efficiency and availability at a low enough cost to become the primary source of power in the future—the only question is, When?
Distributed actuation attacks in wireless sensor networks: implications and countermeasures

This paper investigates the loss of sensing fidelity in a wireless sensor network resulting from a proposed novel attack. The active attack is carried out by a distributed malicious sensor actuator network (mSAN) which is able to actuate or change sensed parameters of the surrounding environment under observation. We show how the attack effectively produces a denial of service on the sensing (DoSS) of a legitimate network, causing it to observe and record false intelligence about the environment. We demonstrate how a controlled level of random mobility in the network counters the attack under various deployments, network densities and actuation radii. We conclude that a random uniform distribution may be most resilient against these attacks and that a strictly deterministic grid deployment may be most vulnerable under certain circumstances. In general we note that in physically hostile environments where sensing fidelity is important, node location becomes as sensitive for dependability purposes as encryption information.
Processing-Structure-Property Relations of Polymer-Polymer Composites Formed by Cryogenic Mechanical Alloying for Selective Laser Sintering Applications

Cryogenic mechanical alloying (CMA) has been shown to be an effective means for producing composite powders for selective laser sintering (SLS). Unlike composite particles made by a coating process, both phases are continuous throughout the particles formed by CMA. Consolidation of these composite particles via SLS offers the possibility of forming parts with a co-continuous microstructure. In this research, the microstructure of mechanically alloyed polymer-polymer composites for use in the SLS process is investigated using transmission electron microscopy. By varying the charge ratio and milling time of the CMA process, the phase domain size of the resulting composite powder can be manipulated. This ongoing work explores the microstructural evolution as the composite powders are consolidated via SLS into macroscopic parts, as well as the relationships between microstructure and bulk properties.
The use of a genetic algorithm in power plant control system design

The use of a genetic algorithm is studied in designing control systems for a boiler-turbine power plant, with specifics in developing a proportional-integral (PI) controller and a state feedback controller for a non-linear multi-input/multi-output (MIMO) plant model. The plant model is presented along with a discussion of the inherent difficulties in such controller development. A sketch of the genetic algorithm (GA) is presented and its strategy as a method of control system design is discussed.