cssi/SciSciGPT-SciSciNet huggingface dataset:
Sodium boiling transients in oxide-fueled fast reactors

Abstract This paper presents methods and results of a theoretical investigation of the dynamic response of large oxide-fueled fast reactor cores during transient over-power or under-flow situations which result in bulk boiling of the coolant. The validity of the analysis is restricted to the regime before the cladding melts or fails otherwise; that is, before material motion other than that due to thermal expansion is experienced. The model and computational scheme for predicting coolant boiling (sodium voiding) behavior, described in an earlier paper, has been incorporated into a closed loop calculation which includes reactor kinetics with sodium voiding and Doppler reactivity feedbacks. The results of calculations for power increase (reactivity ramp) transients for two cores with different geometry are presented and compared. Results of calculations for a flow coastdown transient are also presented and discussed. Some of the limitations of the model and method are also discussed briefly.
WBC reduction in cryopreserved RBC units.

Background WBC reduction of blood components by filtration is widely practiced to decrease the incidence of alloimmunization. Freezing RBCs reduces the WBC load but is insufficient to achieve the currently recommended US limit of 5 x 10(6) cells per unit. Study design and methods Blood units were WBC reduced by filtration or by buffy-coat (BC) removal and then frozen in the presence of a high-glycerol concentration. The count of residual WBCs was determined by flow cytometry after deglycerolization. Results Without WBC reduction, the total number of WBCs present after freezing and thawing was 11.5 +/- 9.2 x 10(6) WBCs per unit (n = 18). Particulate residues from monocytes and neutrophils that were detected in the remaining cell populations were positive for CD66b, CD3, CD14, and CD41. Removal of 40 mL of BC at the time of blood collection lowered the number of WBCs after freezing and deglycerolization to 1.9 +/- 1.20 x 10(6) per unit (n = 11). Similar results were obtained when only 20 mL of BC was removed using a modified blood-bag design. Unfiltered RBC units that were stored for 15 days at 4 degrees C after BC removal contained fewer than 5 x 10(6) WBCs after deglycerolization. Units WBC reduced by filtration before freezing had no detectable WBCs after thawing and washing (n = 14) and did not contain particulate residues. Filtration after deglycerolization was effective in reducing the WBC count below 10(6), although some debris was still present. Conclusion RBC freezing alone will not reduce residual counts to recommended levels. However, initial removal of BC can provide an economical alternative to WBC filtration for cryopreserved units. Units that were not WBC reduced before freezing can be filtered after deglycerolization when needed.
Modeling of diesel combustion, soot and NO emissions based on a modified eddy dissipation concept

A three-dimensional reacting flow modeling approach is presented for predictions of compression ignition, combustion, NOx and soot emissions over a wide range of operating conditions in a diesel engine. The ignition/combustion model is based on a modified eddy dissipation concept (EDC) which has been implemented into the KIVA-3 V engine simulation code. The modified EDC model is used to represent the thin sub-grid level reaction zone and the small scale molecular mixing processes. In addition, a realistic transition model based on the local normalized fuel mass fraction is implemented to shift from ignition to combustion. The modified EDC model is combined with skeletal n-heptane chemistry and a soot dynamics model, which includes nucleation, surface growth and oxidation and coagulation processes. The NO formation and destruction processes are based on the extended Zeldovich reaction mechanism. The modeling results are calibrated against experimental engine data taken at benchmark conditions. The model is...
Dynamic queue control functions for ATM ABR switch schemes: design and analysis

The main goals of a switch scheme are high utilization, low queuing delay and fairness. To achieve high utilization the switch scheme can maintain non-zero (small) queues in steady state which can be used if the sources do not have data to send. Queue length (delay) can be controlled if part of the link capacity is used for draining queues in the event of queue build up. In most schemes a simple threshold function is used for queue control. Better control of the queue and hence delay can be achieved by using sophisticated queue control functions. It is very important to design and analyze such queue control functions. We study step, linear, hyperbolic and inverse hyperbolic queue control functions. Analytical explanation and simulation results consistent with analysis are presented. From the study, we conclude that inverse hyperbolic is the best control function and to reduce complexity the linear control function can be used since it performs satisfactorily in most cases.
Nonlinear interface tunneling phase shift

Near the total-internal-reflection state, the increasing tunneling of the optical field into a nonlinear thin film gives rise to large intensity-dependent phase-shift effects, regardless of whether the incident field will finally achieve a transmissive state. We present a quantitative calculation of the dynamics of this effect and some qualitative experimental results.
Pentose Nucleotides in the Cytoplasm of Growing Tissues

INTEREST in the nucleic acid metabolism of mitosis has in general tended to centre on the nucleus. More recently evidence has been obtained showing an interplay between the nucleic acid metabolism of the nucleus and that of the cytoplasm1. Studying the ultra-violet absorption spectra of the cytoplasms of growing tissues, we have found them all to exhibit the maximum around 2600 A., characteristic of the cyclic nitrogenous bases present in the nucleic acids. In contrast, the homologous mature tissues exhibit a different absorption similar to that of the proteins.
Antioxidative effects of purine bases on hydrogen peroxide oxidation of pyrimidine bases.

Guanylic, polyadenylic, and adenylic acids were tested for their abilities to inhibit hydrogen peroxide oxidation of the base moieties of polycytidylic and polyuridylic acids. Guanylic acid protected both of these substrates, but adenylic acid protected neither. Polyadenylic acid showed antioxidative capacity only when complex formation could occur, i.e., in the presence of polyuridylio acid. The chelating agent, ethylenediaminetetraacetic acid, was as effective as guanylic acid in protecting both pyrimidine substrates.
From Insect Sense Organs to Biomimetic Walking Robots [Exploratory DSP]

In this article, we have pointed out several features of the sensory systems of insects that help these animals control their extraordinarily adaptable and agile locomotion on land. These impressive but often counterintuitive features allow the effects of sensory input to be adjusted continually according to the activity in which the insect is actively engaged, in contrast with hardwired reflexes that must be overcome as the animal switches from one activity to another. The pertinent question is how engineers can incorporate these and other features of biological systems into walking robots.
BETWEEN WELFARE AND WORK: THE ROLES OF SOCIAL SERVICE ORGANIZATIONS IN THE SOCIAL REGULATION OF LABOR MARKETS AND REGULATION OF THE POOR

In the literature on the social regulation of labor markets, the point is often made that employers are not the only significant actors. Within the context of welfare “reform,” with its punitive work requirements and time limits for support, other institutions and actors are being revealed as significant for both the regulation of the labor market and the regulation of the poor. This paper seeks to conceptualize the multiple roles of non-profit social service organizations (SSOs) by connecting their everyday practices to a broader consideration of SSOs as significant mediating institutions that construct particular types of linkages between public assistance and waged labor. Interviews with directors of these organizations in Buffalo, New York in 1977 demonstrate that SSOs have significant impacts on the social regulation of the poor and on the implementation of welfare reform through internal rules, enforcement of broader social policy, job training and educational programs, and general family support. F...
Huntingtin aggregates may not predict neuronal death in Huntington's disease

The mechanism by which polyglutamine expansion in Huntington's disease (HD) results in selective neuronal degeneration remains unclear. We previously reported that the immunohistochemical distribution of N-terminal huntingtin in HD does not correspond to the severity of neuropathology, such that significantly greater numbers of huntingtin aggregates are present within the cortex than in the striatum. We now show a dissociation between huntingtin aggregation and the selective pattern of striatal neuron loss observed in HD. Aggregate formation was predominantly observed in spared interneurons, with few or no aggregates found within vulnerable spiny striatal neurons. Multiple perikaryal aggregates were present in almost all cortical NADPH-diaphorase neurons and in approximately 50% of the spared NADPH-diaphorase striatal neurons from early grade HD cases. In severe grade HD patients, aggregates were more prominent as nuclear inclusions in NADPH-diaphorase neurons, with less perikaryal and neuropil aggregation. In contrast, nuclear or perikaryal huntingtin aggregates were present in less than 4% of the vulnerable calbindin striatal neurons in all HD cases. These findings support the hypothesis that polyglutamine aggregation may not be a predictor of cell loss. Rather than a harbinger of neuronal death, mutant huntingtin aggregation may be a cytoprotective mechanism against polyglutamine-induced neurotoxicity.
The effect of continuous positive air pressure (CPAP) on nightmares in patients with posttraumatic stress disorder (PTSD) and obstructive sleep apnea (OSA).

Objectives:Post-Traumatic Stress Disorder (PTSD) is increasingly prevalent among Veterans characterized by recurrent nightmare and disrupted sleep. Veterans with PTSD also have a high prevalence of...
Modification of Summertime Arctic Cloud Characteristics between a Coastal and Inland Site

Abstract Cloud characteristics at two sites on the North Slope of Alaska separated by ∼100 km have been examined for the warmer months of 2001–03 using data collected from microwave radiometers, ceilometers, rotating shadowband radiometers, and pyranometers. Clouds at the inland site, Atqasuk, were found to have approximately 26% greater optical depths than those at the coastal site, Barrow, and the ratio of measured irradiance to clear-sky irradiance was nearly 20% larger at Barrow under cloudy conditions. It is hypothesized that a significant factor contributing to these differences is the upward fluxes of heat and water vapor over the wet tundra and lakes. Support for this hypothesis is found from the behavior of the liquid water paths for low clouds, which tend to be higher at Atqasuk than at Barrow for onshore winds but not for offshore ones, from differences in sensible heat fluxes, which are small but significant over the tundra but are nearly zero over the ocean adjacent to Barrow, and from the mi...
Delayed loss of p75 neurotrophin receptor-immunoreactivity in the rat suprachiasmatic nucleus and intergeniculate leaflet after binocular enucleation

The rat suprachiasmatic nucleus (SCN) contains a dense plexus of low-affinity p75 neurotrophin receptor (p75NTR)-immunoreactivity. Scattered patches of p75NTR immunoreactivity are present in the intergeniculate leaflet (IGL). Both SCN and IGL receive a direct retinal input. After binocular enucleation, there is a delayed loss of p75NTR-immunoreactivity in the SCN and IGL beginning at, respectively, 4 and 8 weeks post-enucleation, with complete loss occurring in both nuclei by week 12. This delayed loss may be due to an up-regulation of growth factor secretion by local cells in response to retinal axon degeneration.
Phenylephrine to increase blood flow in the radial artery used as a coronary bypass conduit.

Objective The radial artery has more smooth muscle in its wall than the other arterial conduits and is known to be vasospastic. Because it is frequently necessary to use vasoconstrictors early after coronary bypass surgery we investigated the effects of phenylephrine on conduit flow in this setting. Methods Thirty patients undergoing coronary artery bypass with all arterial conduits in which the radial artery was used as a T-graft were randomly assigned to receive intravenous infusions of normal saline (n = 10); nitroglycerin, 0.5 μg · kg · min (n = 11); or nicardipine, 0.5 μg · kg · min (n = 9), beginning early in the operation. After discontinuation of cardiopulmonary bypass and achievement of stable hemodynamics, control measurements were obtained, and this was followed by phenylephrine infusion to achieve a 20% increase in mean arterial pressure, after which the measurements were repeated. Results Mean radial artery flow increased similarly in all groups: normal saline, 40% ± 25%; nicardipine, 37% ± 27%; nitroglycerin, 48% ± 36% ( P = .533). Comparable changes occurred in arterial pressure and systemic vascular resistance, whereas the cardiac index remained unchanged. Conclusion Radial artery blood flow increases when the mean arterial pressure is increased with phenylephrine. There was no evidence of a conduit vasoconstrictive effect, which could limit or reduce conduit flow. Vasocontriction with phenylephrine is appropriate to provide adequate perfusion pressure for radial artery grafts.
Acoustic nuclear spin resonance in metals

Abstract The propagation of transverse acoustic waves in metals parallel to a strong d.c. magnetic field is studied. The attenuation of the acoustic wave via magnetic dipole coupling to the nuclear spins is evaluated.
Transient Cavitation in Fluid-Structure Interactions

A generalized column separation model is extended to predict transient cavitation associated with fluid-structure interactions. The essential feature of the combined fluid-structure interaction calculations is the coupling between the fluid transient, which is computed one dimensionally, and the structural response which can be multidimensional. Proper coupling is achieved by defining an average, one-dimensional, structural velocity and by assuming a spatially uniform pressure loading of the structure. This procedure is found to be effective even for complex finite element structural models for which the required computational time step is orders of magnitude smaller than that for the fluid transient. Computational examples and comparison with experimental data show that neglecting cavitation and setting the fluid velocity at all times equal to that of the structural boundary leads to unreal negative pressure predictions. A properly coupled column separation model reproduces the important features of fluid-structure interactions, converges rapidly, and gives reasonable fluid and structural response predictions. 9 refs.
The relationship between demographic factors and attitudes toward mental health services

Considerable effort has been exerted in recent years toward educating the public concerning mental illness and the efficacy of various treatment modalities. Most previous studies of attitudes have focused solely on attitudes toward the mentally ill. In this study we investigated attitudes toward mental health services and found that most people are positively disposed toward the use of these services. Attitudes toward the use of mental health services were affected by the age, sex, race, education, and income of the subjects. In general, differences of attitude lie in the direction that would tend to inhibit utilization among those most at risk.
The nature and evolution of cooperative fishing arrangements in extended jurisdiction zones

Abstract Following the global extension of marine fishery jurisdiction, cooperative fishing arrangements have emerged between coastal nations and distant water fleets. Economic analysis of these arrangements to date has emphasized their bilateral nature and the associated difficulties of influencing and monitoring behavior, including incentive gaps resulting from differing perceptions of the future. When it is recognized that there are many buyers and sellers of “access”, and that the resources themselves are heterogeneous, the magnitude of such gaps diminishes. We develop a theoretical model and provide empirical evidence supporting the position that a competitive “international market for access” is evolving.
“Teacher by day. Lesbian by night”: Queer(y)ing identities and teaching

This article reports on a study that examined how nine K-12 teachers who self-identified as gay or lesbian connected their classroom practices to their experiences as gays and lesbians. The author found that in doing so, they taught in ways that put queer pedagogy into practice. Using a coconstructive grounded theory approach, the author explored participants’ relationships with the term queer and how they enacted queerness as teachers. The author found that even though participants (with one notable exception) rejected the term queer as a means of self-identification, they practiced a range of queer pedagogy. Although all participants queered their teaching practices and saw relationships between their teaching and their experiences as gays and lesbians, the openly gay participants were explicitly able to use their gayness to queer their teaching.
Factors Associated with Unprotected Exposure to 2009 H1N1 Influenza A among Healthcare Workers during the First Wave of the Pandemic

Protecting healthcare workers (HCWs) from occupational exposure to 2009 H1N1 influenza was a challenge. During the first wave of the pandemic, many HCWs reported that they had been exposed to 2009 H1N1 when they were not using respiratory personal protective equipment. Unprotected exposures tended to be more frequent among HCWs caring for patients with atypical clinical presentations.
Titles versus titles and abstracts for initial screening of articles for systematic reviews

Background There is no consensus on whether screening titles alone or titles and abstracts together is the preferable strategy for inclusion of articles in a systematic review. Methods TWO METHODS OF SCREENING ARTICLES FOR INCLUSION IN A SYSTEMATIC REVIEW WERE COMPARED: titles first versus titles and abstracts simultaneously. Each citation found in MEDLINE or Embase was reviewed by two physician reviewers for prespecified criteria: the citation included (1) primary data; (2) the exposure of interest; and (3) the outcome of interest. Results There were 2965 unique citations. The titles first strategy resulted in an immediate rejection of 2558 (86%) of the records after reading the title alone, requiring review of 239 titles and abstracts, and subsequently 176 full text articles. The simultaneous titles and abstracts review led to rejection of 2782 citations (94%) and review of 183 full text articles. Interreviewer agreement to include an article for full text review using the titles-first screening strategy was 89%-94% (kappa = 0.54) and 96%-97% (kappa = 0.56) for titles and abstracts combined. The final systematic review included 13 articles, all of which were identified by both screening strategies (yield 100%, burden 114%). Precision was higher in the titles and abstracts method (7.1% versus 3.2%) but recall was the same (100% versus 100%), leading to a higher F-measure for the titles and abstracts approach (0.1327 versus 0.0619). Conclusion Screening via a titles-first approach may be more efficient than screening titles and abstracts together.
Obtaining generalizability coefficients for clinical evaluations.

This article discusses the determination of reliability coefficients for clinical evaluation forms by use of generalizability theory. This method is contrasted to some of the commonly used measures of interobserver agreement, interobserver reliability, and classical reliability. The value of this method in terms of making recommendations, such as the number ofjudges and the number of items on a form, in order to improve reliability is illustrated by two examples. Also, the difference between norm-referenced decisions and criterion-referenced decisions in determining reliability with this method is presented.
Das neue Transplantationsrecht – ein Abriß

Habemus legem! Am 1.12.1997 trat in Deutschland das “Gesetz uber die Spende, Entnahme und Ubertragung von Organen” (Transplantationsgesetz–TPG) vom 5.11.1997 in Kraft. Eine lang und zah gefuhrte Auseinandersetzung um die Regelung eines bis dato offenen Fragenkreises hatte damit nach fast 30 Jahren zu einem Ergebnis gefuhrt. Nachfolgend wird das Gesetz in seinen Grundzugen vorgestellt und anschliesend unter Einbeziehung der vorangegangenen Diskussion gewurdigt.
In vivo three-dimensional displacement of the distal radioulnar joint during resisted forearm rotation.

Purpose The in vivo displacement of the distal radioulnar joint (DRUJ) while under resisted pronation or supination has never been previously quantified. Being a joint with 3 dimensions of motion (dorsopalmar translation, changes in ulnar variance, and radioulnar coaptation), our purpose was to determine its 3-dimensional (3D) displacement during resisted rotational torque. Methods Ten normal subjects (aged 31.8 years ± 7.8; F, 5; M, 5) were recruited. Computed tomography scans of a subjects' distal forearms were obtained while grasping the handles of a custom apparatus to keep the fist and forearm in neutral rotation. Scanning was performed in 3 conditions: no rotational torque (control), maximum isometric supination, and maximum isometric pronation. The 3D displacement of the DRUJ, using the ulnar fovea as the reference point, during isometric rotational torque was determined using markerless bone registration techniques. Results The mean 3D displacement of the ulnar fovea during maximum isometric pronation and maximum isometric supination was 3.09 mm ± 0.94 and 2.17 mm ± 1.55, respectively. During maximum isometric pronation, the ulnar fovea displaced a mean of 0.51 mm ± 1.79 dorsally . During maximum isometric supination, the ulnar fovea displaced a mean of 0.13 mm ± 2.07 volarly . In both conditions, ulnar variance increased (0.23 mm ± 2.52 for isometric pronation and 0.44 mm ± 1.57 for isometric supination), and there was increased radioulnar coaptation (0.37 mm ± 0.86 for isometric pronation, 0.039 mm ± 0.66 for isometric supination). Conclusions Resisted rotational torque can be applied to the DRUJ while in neutral rotation during computed tomography imaging, producing measurable displacements in 3D. This technique of studying the DRUJ has the potential to improve our ability to detect and quantify instabilities of the DRUJ.
The forest or the trees? Behavioral and methodological considerations for geochemical characterization of heavily-tempered ceramic pastes using NAA and LA-ICP-MS

Abstract In this paper, the utility of LA-ICP-MS for instrumentally separating clay and temper within pottery samples is examined through a well-known case study that has been previously characterized through NAA and petrography. Coarse Orange pottery is composed of kaolinitic clays heavily tempered within volcanic ash from the basalt-rich Tuxtla Mountains of southern Veracruz, Mexico. We attempt to address the following topics with analyses on this pottery: 1) can LA-ICP-MS replicate the same groups previously identified by NAA and petrography; 2) can instrumental isolation of the clay fraction within the pottery replicate known patterns in raw clay source geochemistry in the Tuxtla Mountains; 3) can data for both the clay and volcanic ash fractions of each pottery sherd be combined to simulate the bulk INAA data? The results demonstrate that the clay fraction of the pottery sherds can be isolated. Furthermore, the LA-ICP-MS data for the clay fractions display nearly identical chemistry to available NAA data for raw clay samples collected from geological contexts in the region. Instrumentally isolating the clay fraction in this case eliminates the homogenizing effects of adding a common temper and increases the chemical separation among groups making it easier to identify clay procurement strategies for each specimen. However, focusing only on the clay fraction ignores significant tempering variation. Attempts to simulate the bulk NAA by combining LA-ICP-MS data for clays and temper was reasonably successful in reestablishing the tempering variation lost by exclusive focus on clays, but such an approach could not replace the more precise data generated from NAA and petrography.
Navigating the Ethical Terrain of Spiritually Focused Psychotherapy Goals: Multiple Worldviews, Affective Triggers, and Personal Practices

Constructing mutual, spiritually focused psychotherapy goals is a practice activity fraught with numerous ethical and countertransferential challenges. This article seeks to inform the thinking and enhance the ability of clinical social workers to engage in collaborative and responsive dialogues with their clients regarding the goals of spiritually focused clinical practice by (1) identifying the multiple value frameworks that influence decisions regarding practice goals, (2) articulating some of the ethical complexities and common countertransferential reactions associated with goal setting, and (3) providing self-reflection questions and guides to help therapists navigate the complexities of this material.
Structure and axon outgrowth inhibitor binding of the Nogo-66 receptor and related proteins

The myelin-derived proteins Nogo, MAG and OMgp limit axonal regeneration after injury of the spinal cord and brain. These cell-surface proteins signal through multi-subunit neuronal receptors that contain a common ligand-binding glycosylphosphatidylinositol-anchored subunit termed the Nogo-66 receptor (NgR). By deletion analysis, we show that the binding of soluble fragments of Nogo, MAG and NgR to cell-surface NgR requires the entire leucine-rich repeat (LRR) region of NgR, but not other portions of the protein. Despite sharing extensive sequence similarity with NgR, two related proteins, NgR2 and NgR3, which we have identified, do not bind Nogo, MAG, OMgp or NgR. To investigate NgR specificity and multi-ligand binding, we determined the crystal structure of the biologically active ligand-binding soluble ectodomain of NgR. The molecule is banana shaped with elongation and curvature arising from eight LRRs flanked by an N-terminal cap and a small C-terminal subdomain. The NgR structure analysis, as well as a comparison of NgR surface residues not conserved in NgR2 and NgR3, identifies potential protein interaction sites important in the assembly of a functional signaling complex.
Zeranol (β-resorcylic acid lactone), a common residous component of natural foodstuffs, stimulates developmental growth of the mouse mammary gland

ICR mice ovariectomized at 6 weeks of age were divided into 5 groups and injected s.c. daily for 20 days with: (1) 0.9% NaCl solution containing 0.1 mg/ml gum arabic (controls); (2) zeranol (Z) (1.0 μg/day); (3) progesterone (P) (1.0 mg/day); (4) Z + P or (5) 17β-estradiol (1.0 μg/day) + P (E + P). Mammary gland (no. 4, inguinal) growth was assessed by analysis of mammae wet weight, dry fat free weight, DNA content and mammae whole mount evaluation. Administration of Z, alone or in combination with P, increased all 4 measures of mammary growth (P < 0.05). The combination of Z + P was highly mammogenic, with mammary wet weight, dry weight and DNA content comparable to that obtained with E + P. Mammae development scores of Z + P treated mice were only slightly less than those from E + P treated mice. The mammary glands of Z treated mice had increased duct number (branching) and thickening. The glands of Z + P treated mice had extensive duct branching with occasional lobule-alveolar development. These data indicate that Z, alone or in combination with P, is an effective mammogen possessing mammogenic properties similar to the potent natural estrogen 17β-estradiol.
ɣ And pulse radiolytic study of the antioxidant activity of vitamin E

The radical mechanisms involved in the antioxidant activity of vitamin E are examined by pulse and steady state ɣ radiolysis. A kinetic scheme is proposed for ɣtocopherol oxidation by H3C-CH(OH)OO. radicals.
Rotation, pairing and blocking in high-K isomers explored through the rotational g-factor

The paired superfluid system of nucleons in nuclei, and their excitations, present properties of general physics interest. Collective magnetic g-factors gR, obtained from a novel analysis of data for multi-quasi-particle configurations in high- Kisomers, are shown to exhibit a striking systematic variation with the relative number of proton and neutron quasi-particles, Np − Nn. Basic ideas of pairing, its quenching by quasi-particle excitation and the consequent changes to moment of inertia and collective magnetism are discussed. Existing model calculations do not reproduce the observed gR variation adequately. The new findings open a fresh window on these effects and raise the important question of just which nucleons contribute to the ‘collective’ properties of these nuclei.
Controlling filament pattering by microsecond-pulsed dielectric barrier discharge plasma for biomedical applications

Research investigating the use of non-thermal plasmas for biomedical application has shown plasmas can enhance both survival and death depending on the application. For example plasma can both enhance wound healing [1] cell differentiation and tissue development [2] and induce apoptosis in cancer cells [3]. All of these studies have been performed using either or both types of non-thermal plasmas; plasma jets and dielectric barrier discharge plasmas (DBD). Plasma jet treatments are usually applied to a liquid while DBD plasma treatment can be applied directly cell and tissue surface. Additionally, depending on the application the DBD electrode size can be modified to treat larger surface areas with a single treatment. However, this can affect the discharge characteristics, including streamer and filament formation and patterning, which in turn can result in cell and tissue damage. Therefore controlling the filament patterning, including filament distribution and speed in atmospheric air is of a great concern for biomedical application. In this work we report the range of parameters affecting the filament pattern and their effect on plasma characteristics such as OH-production and reduced electric field. We tested discharge condition at the power range of 0.105 W to 2.1 W for three electrodes with area of 4.15 cm2, 2 cm2 and 0.83 cm2. Using discharge photographs and image analysis it was found that the larger area electrodes (4.15 cm2) for discharge frequencies below 1 kHz resulted in a fast filament kinetics, with a random distribution, contributing to a more uniform filling of the electrode area over time. Frequencies above 1 kHz for the same electrode resulted in repeated filament pattern over time which can cause damage to cells and tissue. In the smaller area electrode (0.83 cm2) fast filament movement was observed only for frequencies less than 500 Hz. In conclusion, DBD treatment uniformity can be controlled by optimizing discharge parameters and electrode area. Changing filament pattern can extended the biological application range for DBD discharges.
New formulation for interferometric synthetic aperture radar for terrain mapping

The subject of interferometric synthetic aperture radar (IFSAR) for high-accuracy terrain elevation mapping continues to gain importance in the arena of radar signal processing. Applications to problems in precision terrain-aided guidance and automatic target recognition, as well as a variety of civil applications, are being studied by a number of researchers. Not unlike many other areas of SAR processing, the subject of IFSAR can, at first glance, appear to be somewhat mysterious. In this paper we show how the mathematics of IFSAR for terrain elevation mapping using a pair of spotlight mode SAR collections can be derived in a very straightforward manner. Here, we employ an approach that relies entirely on Fourier transforms, and utilizes no reference to range equations or Doppler concepts. The result is a simplified explanation of the fundamentals of interferometry, including an easily-seen link between image domain phase difference and terrain elevation height. The derivation builds upon previous work by the authors in which a framework for spotlight mode SAR image formation based on an analogy to 3D computerized axial tomography (CAT) was developed. After outlining the major steps in the mathematics, we show how a computer simulator which utilizes 3D Fourier transforms can be constructed that demonstrates all of the major aspects of IFSAR from spotlight mode collections.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
β-adrenergic stimulation activates early afterdepolarizations transiently via kinetic mismatch of PKA targets

Sympathetic stimulation regulates cardiac excitation-contraction coupling in hearts but can also trigger ventricular arrhythmias caused by early afterdepolarizations (EADs) in pathological conditions. Isoproterenol (ISO) stimulation can transiently cause EADs which could result from differential kinetics of L-type Ca current (ICaL) vs. delayed rectifier potassium current (IKs) effects, but multiple PKA targets complicate mechanistic analysis. Utilizing a biophysically detailed model integrating Ca and β-adrenergic signaling, we investigate how different phosphorylation kinetics and targets influence β-adrenergic-induced transient EADs. We found that: 1) The faster time course of ICaL vs. IKs increases recapitulates experimentally observed ISO-induced transient EADs (which are due to ICaL reactivation). These EADs disappear at steady state ISO and do not occur during more gradual ISO application. 2) This ICaL vs. IKs kinetic mismatch with ISO can also induce transient EADs due to spontaneous sarcoplasmic reticulum (SR) Ca release and Na/Ca exchange current. The increased ICaL, SR Ca uptake and action potential duration (APD) raise SR Ca to cause spontaneous SR Ca release, but eventual IKs activation and APD shortening abolish these EADs. 3) Phospholemman (PLM) phosphorylation decreases both types of EADs by increasing outward Na/K-ATPase current (INaK) for ICaL-mediated EADs, and reducing intracellular Na and Ca loading for SR Ca-release-mediated EADs. Slowing PLM phosphorylation kinetics abolishes this protective effect. 4) Blocking phospholamban (PLB) phosphorylation has little effect on ICaL-mediated transient EADs, but abolishes SR Ca-release-mediated transient EADs by limiting SR Ca loading. 5) RyR phosphorylation has little effect on either transient EAD type. Our study emphasizes the importance of understanding non-steady state kinetics of several systems in mediating β-adrenergic-induced EADs and arrhythmias.
Designing a field experience tracking system in the area of special education

Purpose – To improve the quality of field experience, support field experience cooperation and streamline field experience management, the purpose of this paper is to describe the experience in using Activity Theory to design and develop a web-based field experience tracking system for a special education program. Design/methodology/approach – The authors used Activity Theory to design and develop a web-based field experience tracking system for a special education program. An in-depth evaluation of the developed web-based system including usability testing and actual use of the system was conducted. Findings – The evaluation and data analysis results demonstrate the value of Activity Theory and show that a web-based tracking system is a valuable tool to support the management of pre-service teachers’ field experiences. Originality/value – This is the first paper to discuss the design and development of field experience tracking system using Activity Theory. This paper can be used to motivate other develo...
Effect of decoupled fluid loading on nonlinear vibration of a flat plate

Numerical simulations of nonlinear responses of a flat plate subject to decoupled fluid loading are carried out. Under clamped boundary conditions and subject to forced vibration at its natural frequency corresponding to the (5,1) mode, the various response modes of the plate are determined. It is found that increasing the excitation amplitude, the response changed from periodic to chaotic. In addition, the fluid-wall shear stresses are found to change the response from linear to nonlinear and vice versa depending on their magnitudes. When a static pressure load is combined with fluid-wall shear stresses and low excitation amplitude, the resulting response was chaotic.
Mechanisms in T-wave alternans caused by intraventricular block

It is recognized that 2:1 intraventricular (IV) block can result in T-wave alternans but is usually assumed that it would also affect QRS waveform. Block in a local region is not, however, varied activation sequence of the same muscle mass because the blocked region is not activated and is not part of the mass that is activated in cycles without block. Also, the block region may have electrocardiogram (ECG) effects when its state differs from other regions. In view of those considerations, the ECG effects of IV block were evaluated by using a computer model of excitation and recovery. ECGs were calculated from differences between the excited state and various degrees of recovery. Results provided evidence that boundaries associated with regions of block rather than regions having varied activation sequence were the major factors in T-wave alternans caused by IV block. Effects of the boundaries included cancellation of the effects of IV block on QRS complexes. Findings suggest that IV block cannot be excluded as a mechanism of T-wave alternans in the absence of QRS alternans.
Differential Perceptions of Elementary School Children Representing Distinct Socio-Cultural Backgrounds:

The difference in meaning of ten school-related concepts for 882 fifth grade students representing three socio-economic status levels (SES), two ethnic groups, two sex groups, and three levels of achievement was studied through the use of the semantic differential technique. Ninety three-way analyses of variance tests were run within and between the two ethnic groups. It was concluded: (1) high achievers do not necessarily perceive school-related concepts more positively, potently, and actively than do middle and low achievers; (2) Anglo-and Spanish-American fifth graders perceive school related concepts more similarly than differently; (3) middle and high SES level students perceive school-related concepts more positively, potently, and actively than do low SES level students; (4) females view school related concepts more positively than do males but males tend to view concepts related to self-identity more potently and actively.
Unbalanced synaptic inhibition can create intensity-tuned auditory cortex neurons

Intensity-tuned auditory cortex neurons have spike rates that are nonmonotonic functions of sound inten- sity: their spike rate initially increases and peaks as sound intensity is increased, then decreases as sound intensity is further increased. They are either "unbalanced," receiving disproportionally large synaptic inhibition at high sound in- tensities; or "balanced," receiving intensity-tuned synaptic excitation and identically tuned synaptic inhibition which nei- ther creates enhances nor creates intensity-tuning. It has remained unknown if the synaptic inhibition received by un- balanced neurons enhances intensity-tuning already present in the synaptic excitation, or if it creates intensity-tuning that is not present in the synaptic excitation. Here we show, using in vivo whole cell recordings in pentobarbital-anesthetized rats, that in some unbalanced intensity-tuned auditory cortex neurons synaptic inhibition enhances the intensity-tuning; while in others it actually creates the intensity-tuning. The lack of balance between synaptic excitation and inhibition was not always apparent in their peak amplitudes, but could sometimes be revealed only by considering their relative timing. Since synaptic inhibition is essentially cortical in or- igin, the unbalanced neurons in which inhibition creates in- tensity-tuning provide examples of auditory feature-selectiv- ity arising de novo at the auditory cortex. © 2007 IBRO. Published by Elsevier Ltd. All rights reserved.
Trichloroethylene Cancer Risk: Simplified Calculation of PBPK-Based MCLs for Cytotoxic End Points

Cancer risk assessments for trichloroethylene (TCE) based on linear extrapolation from bioassay results are questionable in light of new data on TCE's likely mechanism of action involving induced cytotoxicity, for which a threshold-type dose-response model may be more appropriate. Previous studies have shown that if a genotoxic mechanism for TCE is assumed, algebraic methods can considerably simplify the use of physiologically based pharmacokinetic (PBPK) models to estimate virtually safe environmental concentrations for humans based on rodent cancer-bioassay data. We show here how such methods can be extended to the case in which TCE is assumed to induce cancer via cytotoxicity, to estimate environmentally safe concentrations based on rodent toxicity data. These methods can be substituted for the numerical methods typically used to calculate PBPK-effective doses when these are defined as peak concentrations. We selected liver and kidney as plausible target tissues, based on an analysis of rodent TCE-bioassay data and on a review of related data bearing on mechanism. Tumor patterns in rodent bioassays are shown to be consistent with our estimates of PBPK-based, effective cytotoxic doses to mice and rats used in these studies. When used with a margin of exposure of 1000, our method yielded maximum concentration levels for TCE of 16 ppb (87 micrograms/m3) for TCE in air respired 24 hr/day, 700 ppb (3.8 mg/m3) for TCE in air respired for relatively brief daily periods (e.g., 0.5 hr while showering/bathing), and 210 micrograms/liter for TCE in drinking water assuming a daily 2-liter ingestion. Cytotoxic effective doses were also estimated for occupational respiratory exposures. These estimates indicate that the current OSHA permissible exposure limit for TCE would produce metabolite concentrations that exceed an acute no observed adverse effect level for hepatotoxicity in mice. On this basis, the OSHA TCE limit is not expected to be protective.
Learning-by-doing and unemployment dynamics☆

Abstract This paper attempts to assess the impact of skill loss on the persistence of cyclical unemployment. The observations from the Current Population Survey and the Bureau of Labor Statistics suggest a countercyclical total unemployment rate that exhibits high persistence. A framework that features search frictions is developed. Households choose search intensities, and firms create vacancies. Workers accumulate skills through past work experience, or a process of learning-by-doing. This paper extends the learning-by-doing framework to consider endogenous skill loss by the unemployed, or a process of loss-of-learning-by-not-doing. An adverse aggregate technological shock induces workers to reduce their search intensity and firms to reduce their creation of vacancies. As unemployment increases, workers lose their accumulated skills. The skill obsolescence causes a decline in the future marginal productivity of workers. The decline in productivity causes a persistence in the cyclical downturn, and a delay in the recovery of the economy. This allows the model to capture the observed unemployment persistence.
Creation and use of a Talairach-compatible atlas for accurate, automated, nonlinear intersubject registration, and analysis of functional imaging data

Spatial normalization in functional imaging can encompass various processes, including nonlinear warping to correct for intersubject differences, linear transformations to correct for identifiable head movements, and data detrending to remove residual motion correlated artifacts. We describe the use of AIR to create a custom, site-specific, normal averaged brain atlas that can be used to map T2 weighted echo-planar images and coplanar functional images directly into a Talairach-compatible space. We also discuss extraction of characteristic descriptors from sets of linear transformation matrices describing head movements in a functional imaging series. Scores for these descriptors, derived using principal components analysis with singular value decomposition, can be treated as confounds associated with each individual image in the series and systematically removed prior to voxel-by-voxel statistical analysis. Hum. Brain Mapping 8:73–79, 1999. © 1999 Wiley-Liss, Inc.
Quantification of Therapists' Manual Assistance on the Leg during Treadmill Gait Training with Partial Body-Weight Support after Spinal Cord Injury

We are studying the forces applied by therapists when assisting on the legs of patients with spinal cord injury (SCI) during body-weight supported treadmill training (BWSTT). This paper presents results from three experiments with three patients and six different therapists. We attached a sensorized orthosis to one of the legs of the patients and measured the forces exerted by the therapists when assisting on that leg through the orthosis. We also measured the kinematics of the shank. The hips and opposite leg were assisted by two other therapists as usual. We found a high repeatability across steps for the forces applied by each therapist. Better-skilled therapists elicited significantly better leg extension in stance phase by exerting significantly larger horizontal forces on the knee during stance. Better-skilled therapists also elicited better toe clearance during initial-to-mid swing, with fewer or no episodes of toe dragging. This better toe clearance was not generally correlated with larger therapist push-up forces at the ankle. We did find, however, that better toe clearance in swing was correlated with better extension of the same leg in stance, suggesting that a normative leg extension in stance contributed to better muscle activity of the same leg in swing. These results provide insight into therapist-assisted gait training, which may be useful for optimizing robotic gait-training devices.
Accurate optical parameter extraction procedure for broadband near-infrared spectroscopy of brain matter.

Modeling behavior of broadband (30 to 1000 MHz) frequency modulated near-infrared (NIR) photons through a phantom is the basis for accurate extraction of optical absorption and scattering parameters of biological turbid media. Photon dynamics in a phantom are predicted using both analytical and numerical simulation and are related to the measured insertion loss (IL) and insertion phase (IP) for a given geometry based on phantom optical parameters. Accuracy of the extracted optical parameters using finite element method (FEM) simulation is com- pared to baseline analytical calculations from the diffusion equation (DE) for homogenous brain phantoms. NIR spectroscopy is performed using custom-designed, broadband, free-space optical transmitter (Tx) and receiver (Rx) modules that are developed for photon migration at wavelengths of 680, 780, and 820 nm. Differential detection between two optical Rx locations separated by 0.3 cm is employed to eliminate systemic artifacts associated with interfaces of the optical Tx and Rx with the phantoms. Optical parameter extraction is achieved for four solid phan- tom samples using the least-square-error method in MATLAB (for DE) and COMSOL (for FEM) simulation by fitting data to measured results over broadband and narrowband frequency modulation. Confidence in numerical modeling of the photonic behavior using FEM has been established here by comparing the transmission mode's experimental results with the predictions made by DE and FEM for known commercial solid brain phan- toms. © The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or