cssi/SciSciGPT-SciSciNet huggingface dataset:
Quantitative fiber tracking of lateral and interhemispheric white matter systems in normal aging: relations to timed performance.

Abstract The integrity of white matter, as measured in vivo with diffusion tensor imaging (DTI), is disrupted in normal aging. A current consensus is that in adults advancing age affects anterior brain regions disproportionately more than posterior regions; however, the mainstay of studies supporting this anterior–posterior gradient is based primarily on measures of the corpus callosum. Using our quantitative fiber tracking approach, we assessed fiber tract integrity of samples of major white matter cortical, subcortical, interhemispheric, and cerebellar systems (11 bilateral and 2 callosal) on DTI data collected at 1.5 T magnet strength. Participants were 55 men (age 20–78 years) and 65 women (age 28–81 years), deemed healthy and cognitively intact following interview and behavioral testing. Fiber integrity was measured as orientational diffusion coherence (fractional anisotropy, FA) and magnitude of diffusion, which was quantified separately for longitudinal diffusivity ( λ L), an index of axonal length or number, and transverse diffusivity ( λ T), an index of myelin integrity. Aging effects were more evident in diffusivity than FA measures. Men and women, examined separately, showed similar age-related increases in longitudinal and transverse diffusivity in fibers of the internal and external capsules bilaterally and the fornix. FA was lower and diffusivity higher in anterior than posterior fibers of regional paired comparisons (genu versus splenium and frontal versus occipital forceps). Diffusivity with older age was generally greater or FA lower in the superior than inferior fiber systems (longitudinal fasciculi, cingulate bundles), with little to no evidence for age-related degradation in pontine or cerebellar systems. The most striking sex difference emerged for the corpus callosum, for which men showed significant decline in FA and increase in longitudinal and transverse diffusivity in the genu but not splenium. By contrast, in women the age effect was present in both callosal regions, albeit modestly more so in the genu than splenium. Functional meaningfulness of these age-related differences was supported by significant correlations between DTI signs of white matter degradation and poorer performance on cognitive or motor tests. This survey of multiple fiber systems throughout the brain revealed a differential pattern of age's effect on regional FA and diffusivity and suggests mechanisms of functional degradation, attributed at least in part to compromised fiber microstructure affecting myelin and axonal morphology.
Recursive array layouts and fast parallel matrix multiplication

Alvin R. Lebeckt Matrix multiplication is an important kernel in linear algebra algorithms, and the performance of both serial and parallel implementations is highly dependent on the memory system behavior. Unfortunately, due to false sharing and cache conflicts, traditional column-major or row-major array layouts incur high variability in memory system performance as matrix size varies. This paper investigates the use of recursive array layouts for improving the performance of parallel recursive matrix multiplication algorithms. We extend previous work by Frens and Wise on recursive matrix multiplication to examine several recursive array layouts and three recursive algorithms: standard matrix multiplication, and the more complex algorithms of Strassen and Winograd. We show that while recursive array layouts significantly outperform traditional layouts (reducing execution times by a factor of 1.2-2.5) for the standard algorithm, they offer little improvement for Strassen’s and Winograd’s algorithms; we provide an algorithmic explanation of this phenomenon. We demonstrate that carrying the recursive layout down to the level of individual matrix elements is counterproductive, and that a combination of recursive layouts down to canonically ordered matrix tiles instead yields higher performance. We evaluate five recursive layouts with successively increasing complexity of address computation, and show that addressing overheads can be kept in control even for the most computationally demanding of these layouts. Finally, we provide a critique of the Cilk system that we used to parallelize our code.
Commentary: Sca-1 and Cells of the Lung: A matter of Different Sorts

In two separate articles published in this issue, Teisanu et al. and McQualter et al. report the use of flow cytometry and cell sorting to identify putative bronchiolar stem cells that are low in expression for the cell surface marker Sca-1 yet negative for CD34, and a mesenchymal, fibroblastic progenitor cell population from the lung that is positive for Sca-1, respectively. At first glance, these studies may seem to suggest that Sca-1 and CD34 are not markers of an epithelial stem cell population in the lung, as we previously determined in studies that identified bronchioalveolar stem cells (BASCs), and may also appear to contradict each other. However, here we point to evidence that the findings of these three studies are not mutually exclusive, and rather, that the different cell isolation and culturing protocols used in these studies have allowed for the identification of unique pulmonary cell populations. Rather than discounting previous work on BASCs, these studies reveal the existence of new methods and new cell types that will be interesting to use in future functional tests for their importance in lung biology and lung disease.
Some Factors Influencing the Induction, Maintenance and Degree of Maternally Transmitted Protective Immunity to Malaria (Plasmodium Berghei)

Abstract A primary infection of the mother rat, induced at the time of mating, promoted a high level of immunity to P. berghei in the progeny. The level of protection diminished markedly when the interval between the time of infection and mating was 2 months or longer. However, some protective immunity was noted in the progeny whose mothers had been infected for as long a period as 9 months. When mothers who had been infected 2 and 4 months previously were rechallenged with infected erythrocytes at the time of mating an enhanced level of maternally derived protective immunity was present in the progeny. Infected and non-infected adult female rats were inoculated with a non-living P. berghei antigen and infected erythrocytes. The level of protective immunity conferred upon the progeny of these animals was compared. The ascending order of protection was as follows: in progeny from (1) non-infected mothers given non-living antigen at time of mating, (2) mothers infected 2 months prior to mating, (3) mothers given an infective inoculum 2 months prior to mating and inoculated with non-living antigen at time of mating, (4) mothers given an infective inoculum 2 months prior to mating and rechallenged with parasitized erythrocytes at time of mating.
Lipid peroxidation accompanies cyclosporine nephrotoxicity: Effects of vitamin E

Lipid peroxidation accompanies cyclosporine nephrotoxicity: Effects of vitamin E. Cyclosporine A (CsA) has been demonstrated to induce renal microsomal lipid peroxidation in vitro . To examine whether CsA induces lipid peroxidation in vivo , uninephrectomized rats were gavaged with vehicle, CsA 12.5 or 25 mg/kg/day for four weeks. CsA-induced reduction in GFR and RBF was associated with a dose-related increase in renal cortical malondialdehyde (MDA) and conjugated diene, as well as a similar increase in arterial MDA. The latter was apparent within two hours of a single intraperitoneal injection of 25 mg/kg CsA and preceded the acute fall in GFR. To address whether lipid peroxidation contributed to CsA nephrotoxicity, rats were gavaged with vehicles, CsA 25 mg/kg/day or CsA plus vitamin E 25 mg/kg/day for eight weeks. Vitamine E, a lipid radical scavenger, inhibited MDA raise and reduced CsA-induced renal damage. Conversely, CsA administration to vitamin E and selenium deficient rats was accompanied by a greater increase in arterial MDA and fall in GFR. These novel findings, that CsA nephrotoxicity is associated with lipid peroxidation and that a chain-breaking antioxidant ameliorates whereas its deficiency exacerbates, indicate a role for lipid peroxidation, presumably free radical-mediated, in CsA toxicity.
Can Democracy Represent Children? Toward a Politics of Difference.

Children and youth under 18 have made significant strides in recent years toward fuller inclusion in democratic processes. These strides, however, rarely rise to the level of direct political representation, whether in changing policies, making laws, or voting. This article argues that democracies will be able to represent children only by transforming what is meant by democratic representation in the first place. It shows why democratic theory has traditionally excluded children, how representation is more than just participation or citizenship, and how current children’s political movements provide lessons for a more expansive politics of direct representation regardless of age.
A Chemical Biology Strategy to Analyze Rheostat-like Protein Kinase-Dependent Regulation

Protein kinases may function more like variable rheostats rather than two-state switches. However, we lack approaches to properly analyze this aspect of kinase-dependent regulation. To address this, we develop a strategy in which a kinase inhibitor is identified using genetics-based screens, kinase mutations that confer resistance are characterized, and dose-dependent responses of isogenic drug-sensitive and resistant cells to inhibitor treatments are compared. This approach has the advantage that function of wild-type kinase, rather than mutants, is examined. To develop this approach, we focus on Ark1, the fission yeast member of the conserved Aurora kinase family. Applying this approach reveals that proper chromosome compaction in fission yeast needs high Ark1 activity, while other processes depend on significantly lower activity levels. Our strategy is general and can be used to examine the functions of other molecular rheostats.
High Performance Liquid Chromatographic Assay of Methoclopramide in Plasma Using a Silica Gel Column and An Aqueous Meobile Phase

Abstract A high performance liquid chromatographic method for quantitating matoclopramide in plasma is presented. Proteins ara precipitated from the plasma sample with acetonitri la containing the internal standard, procainamida. The treated samples ara than analyzad using an Ultrasphere Si column, an aqueous solution at pH 7 of 65% CH3CN and 5.0 mM (NH4)2HPO4 as a mobile phase, and a fluorescence detector. The retention times for drug and intarna1 standard ara 11.2 and 13.2 min, respectively. The caibration curve is Linear from 0.89 to 44.5 ng/ml. The detection limit is 0.89 ng/ml [signaL/hoisa = 31] for 0.2 ml plasma samples Pracision is measured by intraday and intarday coefficients o f variation, which are less than 10%. This method is currently being used for pharmacokinetic studies of methoclopramide.
Scale Evolution of Finite-Amplitude Instabilities on a Coastal Upwelling Front

Nonlinear model simulations of a coastal upwelling system show frontal instabilities that initiate at short alongshore scales but rapidly evolve to longer wavelengths. Several factors associated with the nonstationarity of this basic state contribute to the progression in scale. A portion of the system evolution is associated with the external forcing. Another portion is associated with the alteration of the alongshore mean flow resulting from wave growth. Direct interactions between the finite-amplitude disturbances also promote emergence of new scales. The relative role of each of these mechanisms is isolated through tangent linear simulations about basic states that approximate the nonlinear system to differing degrees. The basic states include an alongshore uniform time-evolving upwelling solution, the alongshore average of a three-dimensionally evolving upwelling solution, and the full three-dimensional nonlinear solution. Disturbance growth about a frozen-field upwelling state is also examined. Perturbation experiments are performed for persistent and relaxed wind forcing. Although the frontal disturbances in the nonlinear model exhibit a progression to larger scale over the full range of forcing scenarios considered, the mechanisms most responsible for the process differ between wind-forced and unforced cases. Under relaxed wind conditions, the perturbation growth experiments indicate that the scale evolution over the first four days is reflected in the way linear disturbances respond to the adjustment of an alongshore uniform upwelling front to wind cessation. The continued increase in scale between days 4 and 7 is related to the linear disturbance evolution on the alongshore average of a flow state that has been altered by wave–mean flow interaction. Past day 7, the observed scale change is not captured in the linear growth experiments and evidently results largely from nonlinear wave–wave interaction processes. Under sustained upwelling winds, the linear growth experiments fail to describe even the earliest scale change in the nonlinear solutions, indicating that nonlinear wave–wave effects are significant from very near the start of the simulations.
Polarization selective motional holeburning for high efficiency, degenerate optical phase conjugation in rubidium

Abstract We have observed high reflectivity (>40) optical phase conjugation for a low pump intensity (100 mW/mm 2 ), using degenerate four-wave mixing in rubidium vapor. The polarization of the beams were selected such that the diffracting grating was formed in the Zeeman sublevel coherence. We find that only a selected band of atoms moving at non-zero velocities contribute to this process, by forming, in the atom's frame, a non-degenerate double- Λ system. This observation makes it possible to construct a simple, compact, and highly efficient phase conjugator using a semiconductor laser, without any modulators, for many applications, without any concern resulting from frequency mismatch between the probe and the conjugate.
Neural activation profile elicited by cues associated with the anxiogenic drug yohimbine differs from that observed for reward-paired cues.

Cues associated with dangerous or rewarding outcomes can themselves elicit neural activation. Previous work in rats has shown that cues associated with morphine, cocaine, nicotine or palatable food can elicit enhanced expression of the immediate-early gene product Fos in discrete brain regions. Activation of the prefrontal cortex has been shown to be particularly prominent. Some studies have also shown prefrontal cortical activation following exposure to fear-inducing stimuli. To investigate the specificity of regional brain Fos activation, we treated rats with an anxiogenic drug, yohimbine (2 mg/kg, intraperitoneally (i.p.)), or water once per day for 10 consecutive days in a test environment distinct from their home cages. Yohimbine elicited a robust locomotor response that progressively sensitized over days. After a 4-day interval, rats were reintroduced to the paired environment, without drug treatment. Rats re-exposed to the environment where they had previously been treated with yohimbine showed conditioned increases in motor activity compared with controls. Fos expression was increased in several brain regions, including the basolateral amygdala, but was unchanged in prefrontal cortex, in contrast to what has been reported for rewarding drugs. These observations show a neural activation profile elicited by cues associated with the anxiogenic drug yohimbine and further support the hypothesis that prefrontal cortex has a specific role in reward expectancy.
Smart catheter flow sensor for continuous regional cerebral blood flow monitoring

This work reports on development of a novel smart catheter flow sensor (SCF) for continuous monitoring of regional cerebral blood flow (CBF). The SCF employs a periodic heating technique rather than continuous heating and calibrates itself every 5 seconds. This approach ensures zero drift for long-term continuous monitoring and can provide reliable data with MEMS-based thin film sensors. In addition, it uses a 4-wire configuration to eliminate lead wire effect and employs ratiometric measurement to deduce the resistance of SCF. Hence, it is more precise when compared to the bridge-type thermal diffusion flow sensor. The developed SCF has a sensitivity of 2.47mV/ml/min in the range from 0 to 100ml/min with a linear correlation coefficient of R2 = 0.9969. It achieves a resolution of 0.5ml/min and an accuracy better than 3ml/min of full scale with both temperature and medium thermal conductivity compensation.
Parametric mixed-integer 0–1 linear programming: The general case for a single parameter

Abstract Two algorithms for the general case of parametric mixed-integer linear programs (MILPs) are proposed. Parametric MILPs are considered in which a single parameter can simultaneously influence the objective function, the right-hand side and the matrix. The first algorithm is based on branch-and-bound on the integer variables, solving a parametric linear program (LP) at each node. The second algorithm is based on the optimality range of a qualitatively invariant solution, decomposing the parametric optimization problem into a series of regular MILPs, parametric LPs and regular mixed-integer nonlinear programs (MINLPs). The number of subproblems required for a particular instance is equal to the number of critical regions. For the parametric LPs an improvement of the well-known rational simplex algorithm is presented, that requires less consecutive operations on rational functions. Also, an alternative based on predictor–corrector continuation is proposed. Numerical results for a test set are discussed.
Effect of oxygenation on levitation force in seeded melt grown single-domain YBa2Cu3Ox

Abstract The effect of oxygenation on the levitation force has been studied for single-domain YBa 2 Cu 3 O x processed by the seeded melt growth (SMG) method. It has been found that oxygenation annealing has a pronounced effect on the levitation force only in the initial period (∼10 h) at 450°C regardless of the sample volume. The experimental results show that the levitation force increases rapidly and begins to saturate after 10 h of oxygen anneal, indicating that the top surfaces are mainly responsible for the levitation force. Using previously published oxygen diffusion data, it has been estimated that the top surface layer (∼2 mm) is fully oxygenated within 10 h. As the sample's top surface is gradually lapped after oxygenation, the levitation force has been found to increase and peak at a depth of 1.5 mm. This result is consistent with the early saturation of the levitation force within a relatively short annealing period (∼10 h).
On the dynamical realization of automata.

A notion of dynamical realizability, meaningful for an arbitrary mapping process f:A → B between arbitrary sets, is defined. It is shown that the next-state map of a finite automaton is always dynamically realizable, and indeed the realization of such an automaton is closely related to the class of systems we called autonomous state classifiers ( Rosen, 1972a ). On the basis of these realizations, we have at our disposal a class of systems simultaneously describable in dynamical and automata-theoretic terms, and in particular we can ask whether the dynamical description subsumes the automata-theoretic one. It appears that such a subsumption cannot be extracted from the dynamical laws alone, but require additional constraints; hence the two descriptions in general are complementary. A number of other features of these dynamical realizations are discussed.
Using metadata for query refinement and recommendation

Lengthy lists of search results are the fruit of both short queries and conventional Web search result displays. They are problematic for meeting user’s information needs. This paper describes topic extraction and representation from metadata, the first part of a project that will develop an interactive visual query refinement and recommendation (QRR) service to alleviate the problems due to lengthy lists of search results. The topic extraction uses the Latent Dirichlet Allocation (LDA) algorithm to mine the intra- and inter-document relations and represent them in topic and features. The paper presents how the LDA algorithm extracts topics and features from metadata records contained in NSDL search results, which will be used by an interactive visual QRR service in the next step of the project.
The Materials Application Programming Interface (API): A simple, flexible and efficient API for materials data based on REpresentational State Transfer (REST) principles

In this paper, we describe the Materials Application Programming Interface (API), a simple, flexible and efficient interface to programmatically query and interact with the Materials Project database based on the REpresentational State Transfer (REST) pattern for the web. Since its creation in Aug 2012, the Materials API has been the Materials Project’s de facto platform for data access, supporting not only the Materials Project’s many collaborative efforts but also enabling new applications and analyses. We will highlight some of these analyses enabled by the Materials API, particularly those requiring consolidation of data on a large number of materials, such as data mining of structural and property trends, and generation of phase diagrams. We will conclude with a discussion of the role of the API in building a community that is developing novel applications and analyses based on Materials Project data.
Coastal Change and Beach Ridges along the Northwest Coast of Peru: Image and GIS Analysis of the Chira, Piura, and Colán Beach-Ridge Plains

Abstract Since approximately 5200 cal yrs BP, five sets of eight to nine beach ridges were built and preserved along the northwestern Peruvian coastal desert (3°30′S–9°S). Potential ridge-building mechanisms in the hyper-arid environment of northwest Peru include El Nino floods and storms, seismic activity, and sea-level change, as well as more gradual climate changes that affected coastal morphology. Image processing and Geographic Information System (GIS) methods were used to analyze aerial photographs and measure historic coastal patterns along three beach-ridge plains over a 37-year time period. Coastal features were digitized from image mosaics of each ridge plain at different time intervals from 1946 up to 1983. Progradation rates were examined at ridge locations north of the Chira River and Piura River, as well as at the base of ephemeral stream valleys in Colan. The total change in beach area was measured from historic aerial photographs taken at different time intervals. The resulting measurement...
Using the Scanning Electron Microscope for Discovery Based Learning in Undergraduate Courses

Laboratory exercises incorporating a Scanning Electron Microscope (SEM) encourage undergraduate students to explore geologic concepts and methods. A variable pressure (VP) SEM, with attached Energy Dispersive Spectrometer (EDS) and Electron Backscatter Diffractometer (EBSD), has been used in introductory, mineralogy, petrology and structural geology courses to examine sand morphology, quantify mineral chemistry, estimate the temperature of metamorphism, identify microfossils, and pursue student-designed research questions. Student response to using the SEM has been overwhelmingly positive. The undergraduate students, regardless of course level, tend to master the basics of operating the SEM quickly. After a half hour (or so), most students feel confident enough to take control of the SEM and use it to answer questions, or test ideas. Laboratory exercises are designed to allow students some freedom to pursue their own ideas and hypotheses within the framework of a broader geologic question or concept.
Controllable thermal expansion of large magnitude in chiral negative Poisson's ratio lattices

Lattices of controlled thermal expansion are presented based on planar chiral lattice structure with Poisson’s ratio approaching -1. Thermal expansion values can be arbitrarily large positive or negative. A lattice was fabricated from bimetallic strips and the properties analyzed and studied experimentally. The eective thermal expansion coecient of the lattice is about = 3:5 10 4 K 1 . This is much larger in magnitude than that of constituent metals. Nodes were observed to rotate as temperature was changed corresponding to a Cosserat thermoelastic solid.
Monitoring head/eye motion for driver alertness with one camera

We describe a system for analyzing human driver alertness. It relies on optical flow and color predicates to robustly track a person's head and facial features. Our system classifies rotation in all viewing directions, detects eye/mouth occlusion, detects eye blinking, and recovers the 3D gaze of the eyes. We show results and discuss how this system can be used for monitoring driver alertness.
The onion technique: indexing for linear optimization queries

This paper describes the Onion technique, a special indexing structure for linear optimization queries. Linear optimization queries ask for top-N records subject to the maximization or minimization of linearly weighted sum of record attribute values. Such query appears in many applications employing linear models and is an effective way to summarize representative cases, such as the top-50 ranked colleges. The Onion indexing is based on a geometric property of convex hull, which guarantees that the optimal value can always be found at one or more of its vertices. The Onion indexing makes use of this property to construct convex hulls in layers with outer layers enclosing inner layers geometrically. A data record is indexed by its layer number or equivalently its depth in the layered convex hull. Queries with linear weightings issued at run time are evaluated from the outmost layer inwards. We show experimentally that the Onion indexing achieves orders of magnitude speedup against sequential linear scan when N is small compared to the cardinality of the set. The Onion technique also enables progressive retrieval, which processes and returns ranked results in a progressive manner. Furthermore, the proposed indexing can be extended into a hierarchical organization of data to accommodate both global and local queries.
Cognitive Strategies and Long-Distance Running:

Long-distance runners utilize either a dissociative cognitive strategy, an associative cognitive strategy, or a combination of both of these strategies, one at a time, at various times while training or racing. Although research findings have indicated that these athletes are able to switch between these two strategies depending on their given running situation, no explanation has been offered as to how this switching is achieved. This article suggests that runners use automaticity and parallel processing in order to accomplish this function. The use of association and dissociation for running-induced pain tolerance is also addressed.
RASTA processing of speech

Performance of even the best current stochastic recognizers severely degrades in an unexpected communications environment. In some cases, the environmental effect can be modeled by a set of simple transformations and, in particular, by convolution with an environmental impulse response and the addition of some environmental noise. Often, the temporal properties of these environmental effects are quite different from the temporal properties of speech. We have been experimenting with filtering approaches that attempt to exploit these differences to produce robust representations for speech recognition and enhancement and have called this class of representations relative spectra (RASTA). In this paper, we review the theoretical and experimental foundations of the method, discuss the relationship with human auditory perception, and extend the original method to combinations of additive noise and convolutional noise. We discuss the relationship between RASTA features and the nature of the recognition models that are required and the relationship of these features to delta features and to cepstral mean subtraction. Finally, we show an application of the RASTA technique to speech enhancement. >
A Model of the Enlistment Decision under Draft Uncertainty

I. The basic choice situation, 622. — II. Specification of the probabilistic elements of the problem, 624. — III. Optimal enlistment strategies, 626. — IV. The effect of variations in transition rates on the optimal strategy, 629. — V. Uncertainty cost, 632. — VI. Temporary deferments, 634. — VII. Deferment as the subject of strategy, 635. — VIII. Possible empirical application, 636. — IX. Summary and concluding remarks, 637.
The Microbiota and Its Metabolites in Colonic Mucosal Health and Cancer Risk

Recent advances in our ability to identify and characterize the human microbiota have transformed our appreciation of the function of the colon from an organ principally involved in the reabsorption of secretory fluids to a metabolic organ on a par with the liver. High-throughput technology has been applied to the identification of specific differences in microbial DNA, allowing the identification of trillions of microbes belonging to more than 1000 different species, with a metabolic mass of approximately 1.5 kg. The close proximity of these microbes with the mucosa and gut lymphoid tissue helps explain why a balanced microbiota is likely to preserve mucosal health, whereas an unbalanced composition, as seen in dysbiosis, may increase the prevalence of diseases not only of the mucosa but also within the body due to the strong interactions with the gut immune system, the largest immune organ of the body. Such abnormalities have been pinpointed as etiological factors in a wide range of diseases, including autoimmune disorders, allergy, irritable bowel syndrome, inflammatory bowel disease, obesity, and colon cancer. Recognition of the strong potential for food to manipulate microbiota composition has opened up new therapeutic strategies against these diseases based on dietary intervention.
Spatial and temporal variability in early successional patterns of an invertebrate assemblage at an offshore oil platform

Abstract The effects of selected physical and biological factors on the early development of a subtidal invertebrate assemblage were examined at an offshore oil platform in the Santa Barbara Channel (California, USA). The effects of date, year, length, and depth of submersion were investigated by replacing sets of ceramic tiles with new tiles at frequencies of 2, 4, 6, 12, and 24 months at three depths (6, 12, and 18 m) over a period of 24 months. The effects of existing colonists and depth were explored in a second experiment by removing selected early colonists from ceramic tiles deployed at the same three depths over a period of 12 months. More than 40 invertebrate taxa from seven phyla colonized the tiles. Colonial tunicates and encrusting bryozoans appeared early in the successional sequence (∼2 months), in cover ranging from
Virtual reality Stroop task for assessment of supervisory attentional processing

The current project is a preliminary attempt at assessing the potential of a three-dimensional virtual reality Stroop task (VRST) for investigation of supervisory attentional processing. The VRST was compared with paper-and-pencil and computer automated (two-dimensional) versions of the Stroop. Psychophysiological measures were also used to assess varying levels of user arousal. The three versions of the Stroop task were conducted with a sample of 50 healthy university students, between the ages of 18 and 28 years, which included equivalent distributions of men and women from ethnically diverse populations. No significant differences were found for age, gender, or education. Results indicated that the typical Stroop effect pattern found in the Delis–Kaplan Executive Function System (D-KEFS) and Automated Neuropsychological Assessment Metrics (ANAM) occurs in the VRST; the complexity condition of the VRST offers potential for assessment of exogenous and endogenous attentional processing; the two single-ite...
Emergency medical services communication system design

Emergency medical service (EMS) communication system design is discussed. The emphasis is on the development of communication systems to meet the needs of a patient in a medical emergency. Specific factors influencing patient-side portable communications are presented.
Field-induced strain associated with polarization reversal in a rhombohedral ferroelectric ceramic

The polarization reversal process in a rhombohedral ferroelectric ceramic material was investigated using field-induced strain measurements and texture development. Special attention was focused on the difference in the field-induced strains between the first quarter cycle and subsequent loading conditions. Results show that the initial field-induced strain is about twelve times greater than the subsequent strain, which immediately suggests that mechanisms involved in these conditions during the polarization reversal process are different. The difference in the magnitude of field-induced strain is discussed in terms of 180° and non-180° domain reorientation processes.
Orally administered microencapsulated Bordetella pertussis fimbriae protect mice from B. pertussis respiratory infection

Fimbriae from Bordetella pertussis have been encapsulated in poly(lactide-co-glycolide) microparticles of a size appropriate for uptake by the immune inductive tissues of the gastrointestinal tract. Mice were immunized by oral gavage with a single dose of 10 micrograms of microencapsulated fimbriae. The resulting immune responses were compared with those resulting from intraperitoneal injection of mice with equivalent amounts of fimbriae absorbed onto alhydrogel. The examination of serum and mucosal secretions, collected over a 6-week period, for specific antifimbrial antibodies clearly demonstrated that only orally immunized animals mounted measurable immune responses in external secretions. Six weeks after immunization, all immunized animals were protected against intranasal challenge with live B. pertussis.
Braving New Worlds: To Conquer, to Endure

Marilyn Moffat, PT, PhD, FAPTA, CSCS Dr Moffat has had a tremendous impact on the physical therapy profession as a visionary leader, a distinguished educator, and an accomplished clinician, administrator, and researcher. She has served as editor of Physical Therapy and, as an elected member of APTA's House of Delegates, has been instrumental in providing direction for the future of the profession. She has served as a member of innumerable committees, task forces, and boards of directors at every level within the Association. In 1991, she was elected President of APTA for the first of 2 consecutive terms. As President, Dr Moffat spearheaded the development of the Association's Guide to Physical Therapist Practice , and she later served as a project editor of the Guide's second edition and was heavily involved in the development of the Interactive Guide on CD-ROM. Dr Moffat has worked tirelessly since 1977, when she first spoke about the professional doctoral degree for physical therapists, to lead the profession through a process of redefining the role of the physical therapist for the future and ensuring that the highest level of practice would be achieved as a requisite for assuming the title “Doctor of Physical Therapy.” As a delegate to the World Confederation for Physical Therapy, Dr Moffat has provided leadership to the international community of physical therapists. She served as APTA's voting delegate to the WCPT General Meeting, on the Executive Committee of the WCPT as the North America/Caribbean Region representative, and as a member of the Task Force on the International Definition of Physical Therapy. Dr Moffat has given more than 800 professional presentations worldwide and has taught and consulted in Taiwan, Thailand, Burma, Puerto Rico, Vietnam, Hong Kong, and Wuhan in China. For her demonstrated worldwide leadership in physical therapy, she was honored with WCPT's Mildred Elson Award for International Leadership in Physical Therapy. Dr Moffat has been the recipient of many APTA honors and awards. She has been recognized with APTA's Lucy Blair Service Award and as a Catherine Worthingham Fellow. She has received 2 diversity awards from the Advisory Panel on Minority Affairs, the R Charles Harker Policy Maker Award from APTA's Health Policy and Administration Section, and the Robert Dicus Outstanding Service Award from APTA's Private Practice Section. The most significant acknowledgments of her lifelong commitment to service are the New York Chapter's Dr Marilyn Moffat Distinguished Service Award and APTA's newly created Marilyn Moffat Leadership Award.
Cells in culture from rabbit medullary thick ascending limb of Henle's loop

Freshly isolated cells obtained from the medullary segment of the rabbit thick ascending limb of Henle's loop (mTALH) metabolize arachidonic acid (AA) primarily by the cytochrome P-450 monooxygenase pathway forming several products; a vasorelaxant and an inhibitor of Na+-K+-ATPase have been identified. These studies have been extended to mTALH cells in culture. The ability of cells isolated from 1-mo-old rabbits to grow in culture far surpassed that of cells isolated from adult rabbits, whereas similar cytochrome P-450-dependent AA metabolites were produced by freshly isolated cells from rabbits of both ages. Three-week-old mTALH cultures formed ouabain-sensitive "domes" when grown on plastic surfaces and developed transepithelial voltages (4.7 + 1.2 mV, n = 6) when grown on gas-permeable surfaces. Electron microscopy of the cells showed typical mTALH cell characteristics. The presence of Tamm-Horsfall protein, a surface membrane protein of mTALH cells, in 90-95% of the cells confirmed the homogeneity of the cultures. Although several environmental manipulations were tested, mTALH cells in culture did not produce the same cytochrome P-450-dependent AA metabolites as those produced by mTALH cells before culture. However, a cytochrome P-450-dependent AA metabolite that differs from the AA metabolites formed by freshly isolated mTALH cells was produced by hemin-treated mTALH and heterogenous cell cultures.
Disposition of phenolic and sulfated metabolites after inhalation exposure to 4-chlorobiphenyl (PCB3) in female rats.

PCBs, such as PCB3, are air contaminants in buildings and outdoors. Metabolites of PCB3 are potential endocrine disrupting chemicals and genotoxic agents. We studied the disposition of phenolic and...
Mixed-effect modeling for detection and evaluation of drug interactions: digoxin-quinidine and digoxin-verapamil combinations

Mixed-effect modeling has been suggested as a possible tool to detect and describe drug interactions in patient populations receiving drug combinations for the treatment of disease states. The mixed-effect modeling program, NONMEM, was used to measure the effects of the well-known digoxin-quinidine and digoxin-verapamil drug interactions in 294 patients receiving oral digoxin as hospital inpatients. Fourteen percent of the population took either quinidine or verapamil concurrently with digoxin (mean quinidine dose = 857 +/- 397 mg/day, verapamil = 261 +/- 110 mg/day). Two regression models for digoxin oral clearance were used. Model 1 used the knowledge that digoxin is eliminated by both renal and nonrenal routes (TVCL = ClNR+m.CrCl, where TVCL is the population digoxin oral clearance, ClNR is the nonrenal clearance, and m is the slope of the line that relates creatinine clearance (CrCl) to digoxin clearance); model 2 used a more conventional regression approach with a simple series of multipliers. For both models, quinidine administration decreased population digoxin oral clearance by approximately 45% and verapamil therapy decreased population digoxin oral clearance by approximately 30%. These values are similar to those found by traditional drug interaction studies conducted in small patient or normal subject populations. Mixed-effect modeling can detect clinically relevant drug interactions and produce information similar to that found in traditional pharmacokinetic crossover study designs.
In vitro cell migration as a model for delayed hypersensitivity.

SummaryA study has been made of the abilities of peritoneal exudate cells and spleen cells to migrate from capillary tubes in a tissue culture system. In the presence of PPD, peritoneal exudate cells from animals sensitive to PPD failed to migrate normally, while spleen cells show no consistent response. Inhibition of peritoneal exudate cells in the presence of egg albumin occurred if sensitization had been performed so that delayed skin reactions to egg albumin existed. Inhibition did not occur when early (3–6 hr) edematous reactions to skin testing existed, when significant amounts of circulating antibody to egg albumin were demonstrable. Thus the ability of antigen to inhibit cell migration in tissue culture has been confirmed with peritoneal exudate cells for tuberculin hypersensitivity and this in vitro characteristic has been shown to apply also to the delayed hypersensitivity that develops after immunization with a protein antigen in Freund's adjuvant.
Effects of endurance exercise on serum enzyme activities in the dog, pig and man.

SummaryDaily levels of GOT, GPT, AK and LDH did not change consistently with exercise in any species. The level of CPK each day before exercise presented a consistent rise during the week of exercise in the dog and man but not in the pig. By the third day of resting, all enzyme activities were at control levels. The probable tissue of origin for AK and LDH at rest as well as after exercise was the heart, liver, skeletal muscle and kidney in all three species. Serum CPK was the most sensitive index of acute exercise stress in the trained dogs and men. We have shown that the pig, which exhibits responses to exercise resembling those of man, can be exercise trained. The pig may, therefore, be the more appropriate model for endurance exercise studies.
Capacitively-aided switching technique for high-frequency isolated bus converters

This paper presents a new capacitively-aided zero voltage switching (ZVS) technique for isolated bus converters. The proposed technique helps to achieve ZVS conditions for both inverter and rectifier switches with the aid of magnetizing current of the transformer and capacitors interconnecting primary and secondary side switching nodes. With the proposed topology, the ZVS conditions for inverter and rectifier switches occur at the same time, and (ideally) maintain constant required dead time independent of the load level of the converter. These features are particularly advantageous especially for designs operating at high frequencies where timing control becomes critical. The proposed approach is demonstrated in a 1.4 MHz prototype converter which operates from 36 Vdc and supplies a 12 Vdc output load (i.e., fixed input voltage and fixed voltage transformation ratio, 3 ∶ 1 ) at a 36 W rating. Experimental results show ZVS operation of all devices independent of the load level, and the prototype converter achieves 94% peak efficiency with 300 W/ in3 power density.
Multiagent hierarchical learning from demonstration

Programming agent behaviors is a tedious task. Typically, behaviors are developed by repeated code, test, debug cycles. The difficulty increases in a multiagent setting due to the increased size of the design space. Density of interactions, the number of agents and the agent’s heterogeneity (both capabilities and behaviors) all contribute to the larger design space. This makes training the agents rather than programming them highly attractive. One training approach is Learning from Demonstration (LfD) in which agents learn behaviors in real-time based on provided examples from a human demonstrator. The learned behavior maps environmental features to agent action(s), and is constructed from a database of state/action examples supplied by the demonstrator. The database is constructed interactively: initially, the agent is in “training mode,” where the demonstrator controls the agent. Every time the demonstrator changes the agent’s behavior, the agent saves an example to the database. When the demonstrator is finished collecting examples, the agent learns the behavior, and then enters “testing mode.” The demonstrator may offer corrections to the agent based on observation. These corrections add examples to the database, and the behavior is re-learned. LfD is a natural way to train agents since it closely mimics how humans teach each other. Examples include sports, music, and physical therapy. In my LfD implementation, called Hierarchical Training of Agent Behavior (HITAB), the agents learn behaviors represented as an automaton. HITAB is a supervised machine learning approach which uses a classification algorithm to learn the transitions inside the behavior automaton. Typically, supervised machine learning requires significant data to learn robust behaviors. This is doubly so in complex, high dimensional design spaces. However, gathering data is potentially expensive since each data point requires an experiment (physically or in simulation) conducted in real-time. HITAB’s behavior representation helps reduce the number of required samples by decomposing the task into smaller, less complex tasks. In addition, these smaller tasks might require a reduced set of behaviors and/or features, thus further reducing the design space. Hence, HITAB rapidly learns complex behaviors which are simple from a machine learning perspective. While this places HITAB at the edge of machine learning, it allows novices to train an agent to perform complex behaviors without requiring detailed programming knowledge. 1 Single Agent Model
Does the standard voluntary association question capture informal associations

Sociologists have long been attentive to participation in associational life. Yet, despite being repeatedly cautioned to consider more informal groups, most researchers focus on participation in formal voluntary associations using national surveys with fixed group categories, such as the General Social Survey (GSS). In this paper, we use new GSS data on the names of the voluntary associations listed by respondents to evaluate whether voluntary association prompts capture or miss various types of informal associations. We code the formality of the associations listed by respondents and also compare to a new sample of bottom-up, informal voluntary associations. We demonstrate that some response categories adequately capture both formal and informal associations, e.g., sports groups. However, our results also suggest that the standard voluntary association question both omits entire categories of informal associations and omits some informal variants of associations within categories. In the tradition of Baumgartner and Walker (1988), Wuthnow (1994), and Wellman et al. (2001), we suggest that we may misunderstand citizen associations if we ignore informal associating.