cssi/SciSciGPT-SciSciNet huggingface dataset:
Psychosocial adjustment and physical growth in children with imperforate anus or abdominal wall defects

Abstract Pediatric surgeons have the unique responsibility of performing surgical procedures that will enable their patients to function normally throughout a lifetime. Good anatomic results may not ensure that this goal will be achieved. Using a battery of psychological testing instruments, we evaluated the academic achievement and psychosocial status of 56 children (mean age, 10.6 years) with imperforate anus (IA) and abdominal wall defects (AWDs). Physical growth was assessed by measurement of standard anthropometric parameters, and a parent questionnaire was used to define clinical status. As a group, the children presented with average intellectual ability. Achievement in both reading and math was in the normal range. In 12.5% of the children a reading learning disability was noted and 10.7% had a disability in math. On the basis of parental assessments, 25% of the children demonstrated externalizing behavior disorders (eg, conduct problems) and 29% displayed internalizing symptomatology (eg, withdrawal, anxiety). Social competency deficits were described in 23% of the children. Data obtained from the teachers were consistent with the parental assessments. No major differences between the IA and AWD patients in academic achievement, psychosocial status, or physical growth were discovered. Routine screening of these children for learning disabilities and behavior problems is recommended.
On a Generalized M/G/1 Queuing Process in Which the First Customer of Each Busy Period Receives Exceptional Service

The following generalization of the M/G/1 queue is considered. If a customer arrives when the server is busy, his service time has a distribution function, Gbx; while if he arrives when the server is idle, his service time has a different distribution function, Gex. Results are obtained that characterize the transient and asymptotic distributions of the queue size, waiting time, and waiting-plus-service time. These results are then applied to the special case of a queue with a single service time distribution function, but with additional independent delay times that have one distribution function for the customers arriving when the server is idle and another for the customers arriving when the server is busy.
Adolescents' Submission and Conflict Behaviors with Mothers Predicts Current and Future Internalizing Problems

We tested hypotheses that adolescent behaviors indicating difficulty with individuation from mothers predict current internalizing and increases in internalizing problems a year later. Seventy-eight rural, primarily White working-class adolescents used video recall methods to rate their behaviors with their mothers during a conflict resolution task. Multiple regression and sequential analyses revealed that girls, particularly those with prior internalizing problems, evidenced increased internalizing problems if they had high levels of Conflict and Submission (“agitated submission”). Boys' internalizing problems increased as their Submission, but not Conflict (“disengaged submission”), rose. These behavior patterns may represent gendered vulnerabilities in mastering individuation.
Toward a Theory of Community Conflict: Factors Influencing the Initiation and Scope of Conflict*

A theory of the structure and process of community conflict is developed around concepts used in earlier works in the field. Then propositions relating to the central elements of community conflict are presented by concentrating on the primary variable: scope. Propositions constructed with other relevant structural variables are introduced. To begin with, procedures used in developing the propositions are discussed; and, then, suggestions for measuring them are given. Finally, implications of the theory in analyses of change are discussed.
Level structure of 32P from 31P(d, p)32P reactions

Abstract States up to an excitation energy of 6.8 MeV of the nucleus 32 P are investigated by studying the angular distribution of protons in the reaction 31 P(d, p) 32 P. One new state is found at 1.51 MeV. A state previously reported at 6.56 MeV is found to be a doublet with excitation energies 6.58 MeV and 6.53 MeV. The angular distributions for 28 of the stronger levels are fitted with Butler curves, and probable l n values are given for these levels. Relative reduced widths are given for the same levels. The results are discussed in terms of the Nilsson rotational model and the shell model.
Proton distribution and site energies in group IIIB metal hydrides

Abstract The proton occupation of octahedral sites adjacent to dilute Er ions in ScH x and YH x is determined from electron spin resonance signal intensities, and explained by a lattice-gas model which yields bulk proton site energy differences in these isostructural materials.
An ultra-thin interposer utilizing 3D TSV technology

To achieve ultra small form factor package solution, an ultra-thin (50µm) Si interposer utilizing through-silicon-via (TSV) technology has been developed. Challenges associated with handling thin wafer and maintaining package co-planarity have been overcome to stack thin dies (200 µm) on ultra-thin interposer. Improved electrical performance and the advantages of this innovative thin interposer are highlighted in this paper. Warpage behavior is investigated with simulation and experiments to ensure reliability and robustness of the Si stack. Reduction in package thickness is realized to achieve high functionality, small form factor, better electrical performance and robust reliability by stacking thin dies on ultra-thin interposer.
Effect of resin surface sealers on improvement of stain resistance for a composite provisional material.

Background: Resistance to staining is desirable to maintain the esthetic appearance of a provisional material. A resin sealant may improve stain resistance. Purpose: Color changes of a resin composite provisional material were measured by reflection spectrophotometry after storage in three staining solutions and water to determine stain resistance when treated with three methacrylate or urethane dimethacrylate resin surface sealants and when left untreated. Materials and Methods: Specimens of a resin composite provisional material received one of three resin sealants (Fortify Plus°, Bisco, Inc., Schaumburg, IL; Jet Seal°, Lang Dental Manfacturing, Wheeling, IL; Triad LC°, Dentsply International, York, PA, USA) or no surface sealer and then were stored for 72 hours in one of four staining solutions (water [control], black coffee, cranberry juice, red wine). Color was measured by CIE L*a*b*on a reflection spectrophotometer (Color-Eye° 7000, Macbeth Division, Kollmorgen Instruments, Newburgh, NY, USA) at baseline and after storage. Color change (ΔE*) was calculated and analyzed statistically by two-factor analysis of variance, with four solutions and four surface treatments as independent variables. Results:ΔE* ranged from 0.7 to 1.7 in water, from 1.1 to 5.5 in cranberry juice, from 1.1 to 6.5 in black coffee, and from 1.5 to 3.9 in red wine. Statistically significant differences were observed (p 3.3) and Jet Seal and Triad LC showing decreased staining (AE* < 2.0) in cranberry juice and coffee compared with staining of the unsealed specimens. Only Jet Seal provided resistance to staining in red wine. Conclusions: Specimens without a surface sealer had statistically higher (p <.05) and perceptible or nearly perceptible color changes in cranberry juice, black coffee, and red wine than in water. Specimens coated with Jet Seal had statistically lower (p < .05) color changes than uncoated specimens in cranberry juice, black coffee, and red wine. When coated, the color changes of the stained specimens were not perceptible. Specimens coated with Triad LC had statistically lower (p < .05) color changes than unsealed specimens in cranberry juice and black coffee. When sealed, the color changes of the specimens stained with cranberry juice and black coffee were not perceptible. Both unsealed and sealed specimens stained with red wine were nearly perceptible. Specimens coated with Fortify Plus had statistically higher (p <.05) color changes than uncoated specimens in cranberry juice and black coffee but statistically the same (p <.05) color change as uncoated specimens in red wine. These specimens had perceptible color changes in cranberry juice, black coffee, and red wine. CLINICAL SIGNIFICANCE Surface sealers of methacrylate or dimethacrylate resins can improve resistance of a resin composite provisional material to staining caused by cranberry juice, black coffee, and red wine.
Location of frame overlap choppers on pulsed source instruments

A detailed study has been performed to investigate the effect of frame overlap in a cold neutron chopper spectrometer. The basic spectrometer is defined by two high-speed choppers, one near the moderator to shape the pulse from the moderator, and one near the sample to define energy resolution. Using ray-tracing timing diagrams, we have observed that there are regions along the guide where the trajectories of neutrons with different velocities converge temporally at characteristic points along the spectrometer. At these points of convergence, a frame overlap chopper would be totally ineffective, allowing neutrons of all velocities to pass through. Conversely, at points where trajectories of different velocity neutrons are divergent, a frame overlap chopper is most effective. An analytical model to describe this behaviour has been developed, and leads us to the counterintuitive conclusion that the optimum position for a frame overlap chopper is as close to the initial chopper as possible. We further demonstrate that detailed Monte Carlo simulations produce results which are consistent with this model.
Residual thermal stresses and strains in a WC-base cemented carbide composite

Abstract Residual thermal strains in a WC-Ni cemented carbide composite at various temperatures were computed using a spheroidal geometry of the WC particles. The results were compared with residual strains measured in the WC particles by a neutron diffraction technique. The anisotropy and the variations of the measured strains with temperature were correctly predicted by assuming that the aspect ratio (L a :L c ) of the particles is 1.8.
The Ultrastructure and Functional Morphology of a Captaculum in Graptacme calamus(Mollusca, Scaphopoda)

The structure and function of the captaculum in Graptacme calamuswere studied using light microscopy, videomicrography, and transmission electron microscopy. Graptacme calamusutilizes a longitudinal ciliary band to transport small food particles along the outstretched filament. The head of the captaculum, which bears the alveolar indentation, contains a large ganglion, at least three types of gland cells, circular and longitudinal muscles, and connective tissue. It is likely that gland 1 secretes mucus which is used in the transport of food particles and that gland 2 secretes material which promotes adhesion of the alveolus to the substratum. The function of gland 3 is unknown. Critical observation of the captaculum surface revealed that the cilia of the alveolar region have truncated tips unlike those found on other regions of the captaculum. These alveolar cilia probably aid in the distribution of adhesive substance and in adhesion.
Nano-structure computation with coupled momentum phase ordering kinetics models

When a system such as a binary liquid is cooled rapidly from a homogeneous phase into a two-phase region, domains of the two equilibrium phases form and grow (coarsen) with time. In the absence of external forcing, such as by gravity or an imposed shear flow, a dynamical-scaling regime emerges in which the domain morphology is statistically self-similar at different times, with an overall length-scale (coarsening scale) that grows with time. In the first part of the paper, the scaling phenomenology will be reviewed and the time-dependence of the coarsening scale will be discussed in the context of a number of different physical systems and scaling regimes. In the second part, the influence of external drives, in particular gravity and shear flow, will be addressed and recent results reviewed. In particular, we find that multiple length scales emerge since in the shear case the system coarsens more rapidly in the mean flow direction while in the gravity case the coarsening is more rapid in the direction of the gravity. We characterized the scales by calculations of the anisotropic growth laws. Further for the shear we show that it is possible to control the asymptotic morphology of the phase separation in order to obtain either lamellae or cylindrical structures and potentially create for example nano-conductive wires or materials with particular optical properties. Investigating gravitational effects we find that scaling laws are significantly affected even for small density mismatch or low gravity, and the growth mechanism has some similarities to the sedimentation process.
Adrenalectomy increases phosphoinositide hydrolysis induced by norepinephrine or excitatory amino acids in rat hippocampal slices.

Abstract Phosphoinositide hydrolysis induced by norepinephrine, quisqulate, or trans-1-amino-1,3-cylopentanedicarboxylic acid (ACPD), but not by carbachol, was approximately 50% greater in hippocampal slices from adrenalectomized (14 days) rats compared with controls. These changes appeared to be selective for the hippocampus because no effects of adrenalectomy on phosphoinositide hydrolysis were detected in cortical or striatal slices. The enhanced response to norepinephrine in hippocampal slices after adrenalectomy was observed throughout the effective concentration range of norepinephrine, was not influenced by in vitro addition of corticosterone, was not mimicked or altered by incubation with dibutyryl cyclic adenosine 3′,5′-monophosphate (AMP), and did not appear to be due to impaired inhibition of the response to norepinephrine which was elicited by activation of protein kinase C or by inclusion of an inhibitory concentration of quisqualate. These findings indicate that adrenalectomy either removes an inhibitory influence of glucocorticoids on the phosphoinositide system in the hippocampus or that the neurodegeneration of granule cells in the dentate gyrus following adrenalectomy is associated with neurotransmitter-selective increases in phosphoinositide hydrolysis. These data provide further evidence that glucocorticoids modify signal transduction in the brain and extends their known influence to the phosphoinositide second messenger system.
Complicated Clostridium difficile colitis in children with cystic fibrosis: Association with gastric acid suppression?

Patients with cystic fibrosis (CF) have several risk factors for Clostridium difficile colonization such as frequent hospitalization and exposure to a broad array of antibiotics utilized for the control, eradication, and prophylaxis of respiratory pathogens. However, despite this high rate of colonization, the occurrence of C. difficile infection (CDI) in CF is rare. We report three children with CF who presented with severe community-associated CDI. All three children had complicated courses and one died. These children were in good health without significant morbidities, and were not frequently hospitalized nor did they receive frequent antibiotic courses. The occurrence of 3 severe cases within a 15-month period prompted us to report these cases and review the literature in regard to CDI. We reviewed the CF GI tract as possible risk factors for a high rate of C. difficile colonization in individuals with CF. Since a high percentage of individuals with CF are on gastric acid blocking agents, we also focused on gastric acid suppression as a potential risk factor for CDI.
AirSR, a [2Fe-2S] cluster-containing two-component system, mediates global oxygen sensing and redox signaling in Staphylococcus aureus.

Oxygen sensing and redox signaling significantly affect bacterial physiology and host-pathogen interaction. Here we show that a Staphylococcus aureus two-component system, AirSR (anaerobic iron-sulfur cluster-containing redox sensor regulator, formerly YhcSR), responds to oxidation signals (O2, H2O2, NO, etc) by using a redox-active [2Fe-2S] cluster in the sensor kinase AirS. Mutagenesis studies demonstrate that the [2Fe-2S] cluster is essential for the kinase activity of AirS. We have also discovered that a homologue of IscS (SA1450) in S. aureus is active as a cysteine desulfurase, which enables the in vitro reconstitution of the [2Fe-2S] cluster in AirS. Phosphorylation assays show that the oxidized AirS with a [2Fe-2S]2+ cluster is the fully active form of the kinase but not the apo-AirS nor the reduced AirS possessing a [2Fe-2S]+ cluster. Overoxidation by prolonged exposure to O2 or contact with H2O2 or NO led to inactivation of AirS. Transcriptome analysis revealed that mutation of airR impacts the ...
Phenol/acetone cogeneration via solid acid catalysis

Abstract Phenol/acetone cogeneration via cumene hydroperoxide (CHP) cleavage has been demonstrated using various classes of novel solid acid catalysts. Mineral acid-treated montmorillonite silica-alumina clays, heteropoly acids impregnated into Group IV oxide supports, fluorophosphoric acid and HF-treated oxides, as well as montmorillonite clays modified with heteropoly acids or certain Lewis acids, are each effective. The influence of solid acid structure upon phenol yields has been examined while minimizing by-product acetophenone, 2-methylstyrene, 2-phenyl-2-propanol, mesityl oxide formation, etc. For the more promising candidates, decomposition of 80% CHP solutions in continuous, plug-flow reactor systems, under mild conditions (ca. 60°C at LHSVs≈10) has been realized.
Inactivation of papain by pulsed electric fields in a continuous system

Papain (E.C. 3.4.22.2), a cysteine protease in papaya, was activated with reducing agents and treated with pulsed electric fields (PEF) in a continuous system at 10°C. Irreversible reduction of activity was observed in PEF-treated papain after 24 h storage at 4°C. Oxidation of papain active site, a cyteine residue, was not the major cause of papain inactivation by PEF. Temperature did not increase over 35°C during PEF treatment. The pH of papain solution was not changed after PEF treatment. Structural change was observed in PEF-treated papain by CD analysis. Inactivation of PEF-treated papain was related to the loss of α-helix structure. Heating at 60-80°C for 2 min did not significantly reduce the activity of papain.
Pioneering Risk: Lessons from the US Teletext/Videotex Failure

Digital teletext/videotex services enjoyed a decades-long heyday in Europe, and only recently have largely given way to the far more capable Internet. But neither service succeeded in the US. This article assesses multiple reasons behind the American failure to adopt this technology, some of which apply to today's digital services
Revolution to Secession: Constitution Making in the Old Dominion

Traces the development of Virginia's Constitution and looks at the forces shaping its change.
Concluding Observations and Implications of E-Portfolios for Student Affairs Leadership and Programming

This chapter provides an overview of the preceding chapters and concluding observations and recommendations.
Symptoms with acid and nonacid reflux may be produced by different mechanisms

Twenty-four-hour multichannel intraluminal impedance and pH (MII-pH) esophageal monitoring detects both acid and nonacid gastroesophageal reflux episodes. The MII-pH catheter contains six impedance segments placed 3, 5, 7, 9, 15, and 17 cm above the lower esophageal sphincter (LES). A pH electrode at 5 cm above the LES identifies the type of reflux, i.e. acid or nonacid. Patients with acid and nonacid reflux exhibit typical and atypical symptoms often within 5 min following a reflux episode. The aim of this study is to compare the timing of symptoms after reflux episodes in patients with acid and nonacid reflux. Methods include a review of 70 MII-pH tracings (42 females, mean age 40, range 18-85 years) either on (50 points) or off (20 points) acid suppression therapy. Typical (heartburn, regurgitation) and atypical (cough) symptoms with acid or nonacid reflux episodes detected by impedance were analyzed. Symptoms were considered positive with acid reflux if there was a pH drop to 4 and MII detected a reflux episode. The timing of the symptom after each reflux episode was recorded. Symptom perception occurred significantly sooner after acid versus nonacid reflux (P < 0.05). Acid reflux episodes are more likely to be perceived in the first 2 min following the reflux episode. Patients with acid reflux are likely to perceive symptoms earlier, and symptoms with acid and nonacid reflux may be produced by different mechanisms.
Design Principles for Nanoparticles Enveloped by a Polymer-Tethered Lipid Membrane

We propose the design for a nanoparticle carrier that combines three existing motifs into a single construct: a liposome is stabilized by anchoring it to an enclosed solid core via extended polymeric tethers that are chemically grafted to the core and physisorb into the surrounding lipid membrane. Such a design would exhibit several enticing properties, among them: (i) the anchoring stabilizes the liposome against a variety of external stresses, while preserving an aqueous compartment between core and membrane; (ii) the interplay of design parameters such as polymer length or grafting density enforces strong constraints on nanoparticle size and hence ensures a high degree of uniformity; and (iii) the physical and chemical characteristics of the individual constituents equip the construct with numerous functionalities that can be exploited in many ways. However, navigating the large parameter space requires a sound prior understanding for how various design features work together, and how this impacts potential pathways for synthesizing and assembling these nanoparticles. In this paper, we examine these connections in detail, using both soft matter theory and computer simulations at all levels of resolution. We thereby derive strong constraints on the experimentally relevant parameter space, and also propose potential equilibrium and nonequilibrium pathways for nanoparticle assembly.
Determinants of Police Job Satisfaction

This paper reports the results of a partial replication and extension of Reiss's (1967) study of police job satisfaction. Utilizing indicators similar to those employed by Reiss, the study first determines the applicability of his results to a second sample of police officers at a more recent time. Second, it explores two new variables potentially related to job satisfaction: years on the force and years in current rank. Third, it employs multiple regression analysis to isolate the most predictive of the variables related to job satisfaction. Four variables account for most of the variance explained. The implications of the findings for enhancing police job satisfaction are examined.
Bandwidth measurements of polymer optical fibers

Instrumentation and general methodology to conduct time domain dispersion measurements on polymer optical fiber are described. The equipment and analysis procedures for performing these measurements at 670 nm are presented together with experimental results on PMMA core fiber. Measured bandwidths are very dependent on launching conditions and may be substantially greater than those predicted for ideal step-index fibers. Effects such as mode dependent attenuation and mode coupling which© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
8.1: Experimental verification of a λ/50 optical spot size of a C-aperture nano antenna tip for photo-electron emitter applications

We propose a photo-electron emitter structure whose electron beam size is 20nm using CsBr photo-emission layer and a novel nano-optical antenna structure. The optical spot size of 20nm has been experimentally demonstrated.
A Peptide Derived from Endostatin Ameliorates Organ Fibrosis

Fibroproliferative disorders such as idiopathic pulmonary fibrosis and systemic sclerosis have no effective therapies and result in significant morbidity and mortality due to progressive organ fibrosis. We examined the effect of peptides derived from endostatin on existing fibrosis and fibrosis triggered by two potent mediators, transforming growth factor–β (TGF-β) and bleomycin, in human and mouse tissues in vitro, ex vivo, and in vivo. We identified one peptide, E4, with potent antifibrotic activity. E4 prevented TGF-β–induced dermal fibrosis in vivo in a mouse model, ex vivo in human skin, and in bleomycin-induced dermal and pulmonary fibrosis in vivo, demonstrating that E4 exerts potent antifibrotic effects. In addition, E4 significantly reduced existing fibrosis in these preclinical models. E4 amelioration of fibrosis was accompanied by reduced cell apoptosis and lower levels of lysyl oxidase, an enzyme that cross-links collagen, and Egr-1 (early growth response gene–1), a transcription factor that mediates the effects of several fibrotic triggers. Our findings identify E4 as a peptide with potent antifibrotic activity and a possible therapeutic agent for organ fibrosis.
Interacting boson approximation model analysis of E 2 transition probabilities for transitions in Er 1 6 6 − 1 7 0

The experimental results from Coulomb excitation of vibrational-like ${2}^{+}$ states in $^{166\ensuremath{-}170}\mathrm{Er}$ are compared with the predictions of the interacting boson approximation model. The breaking of the SU(3) symmetry by the pairing term plays a crucial role in giving a much better account of the $B(E2)$ values for decay of the $K$,${J}^{\ensuremath{\pi}}=0,{2}^{+}$ state. In general, the interacting boson approximation model provides a detailed quantitative description of the level energies and of the $E2$ transition probabilities.
Luminescence phenomena in CsI:Na☆

Abstract Absorption, emission and excitation spectra of CsI : Na were measured on bulk single crystals and thin films at room temperature (RT) and liquid nitrogen temperature (LNT) Excitonic absorption peaks as well as absorption in the long-wavelength tail of the fundamental absorption which is not present in pure CsI were observed. In addition to emission at 4250 A, excitonic emission at 3400 A, normally found at LNT, has also been observed at RT, This room temperature UV emission is closely related to the heat treatment process that the specimen received.
Self-monitoring in the treatment of tics: A single-subject analysis

Abstract The effectiveness of self-monitoring in the treatment of a 17-yr-old female's tics was evaluated using a modified, multiple baseline single-subject design. Self-monitoring was found to reduce both the frequency and intensity of the tics. The advantages of using self-monitoring are discussed.
Differential Binding of Ions and Water in the Unfolding of DNA Hairpins

Stem-loop motifs are appropriate models for the thermodynamic description of the stability and melting behavior of native DNA. In order to improve our understanding of the role of both ions and water in the stability and melting behavior of DNA secondary structures, we used a combination of UV and CD spectroscopies, and DSC calorimetric techniques to determine standard thermodynamic profiles, the differential binding of ions (Δnion) and water (ΔnW) for the unfolding of 22 hairpin loops with different stem sequence and loops of 5 thymines. The CD spectra indicated that all hairpins adopted the B-conformation at low temperatures. The UV and DSC data showed all hairpins unfold in two-state transitions, and accompanied by water releases of 12-24 mol H2O/mol hairpin and ion releases of 0.38-0.76 mol Na+/mol hairpin. Therefore, the folding of each hairpin is accompanied by a favorable free energy term, resulting from the compensation of a favorable enthalpy and unfavorableentropy contributions, due to formation of base-pair stacks and uptake of both water and counterions, respectively.Complete thermodynamic parameters, including ΔnW and Δnion, for all 10 W-C nearest-neighbor contributions were determined by solving the matrix of the thermodynamic data. This allows us to predict the overall thermodynamics, hydration and ion binding properties for the unfolding of a hairpin loop from knowledge of its stem sequence. Supported by Grant MCB-0616005 from the National Science Foundation.
Rapid-cycling populations of Brassica

Rapid-cycling populations of six economically important species in the genus Brassica have unusual potential for resolving many problems in plant biology and for use in education. Rapid-cycling brassicas can produce up to ten generations of seed per year and serve as models for research in genetics, host-parasite relations, molecular biology, cell biology, plant biochemistry, population biology, and plant breeding. Brassicas are a highly diverse group of crop plants that have great economic value as vegetables and as sources of condiment mustard, edible and industrial oil, animal fodder, and green manure. These plants can also be used in the classroom as convenient, rapidly responding, living plant materials for "hands on" learning at all levels of our educational system.
Action of atropine on the turtle heart.

SummaryThe direct action of atropine on cardic muscle has been studied in the whole auricle and ventricular strips of turtle heart. In concentrations far above those that could be used therapeutically, its affect on rhythmicity, contractility, absolute refractory, contractility, absolute refractory period, tonus, and on conductivity at low rates of beating was slight and inconstant. The only significant direct action of atropine on heart muscle appears to be a power to depress conductivity at relatively high rates of beating.
Crayfish walking leg neuronal biosensor for the detection of pyrazinamide and selected local anesthetics

Abstract Neuronal biosensors based on the use of crayfish Procambarus clarkii walking legs are reported for the first time and possible analytical applications are explored. The neuronal biosensor is shown to respond selectively to the antitubercular drug and potent food marker, pyrazinamide. The sensor is characterized with respect to selectivity, dose-response relationship, reproducibility and operating lifetime. The detection of local anesthetics is accomplished by monitoring the decrease in pyrazinamide-induced nerve firing in the crayfish walking leg. This decrease is a result of the local anesthetic block of the axonal sodium channels in the nerves. Applicability of this novel procedure to analytical measurements is demonstrated by the construction of dose-response curves for several local anesthetics. Problems associated with the current sensor configuration are presented and future research directions that may improve the neuronal-based biosensor are discussed.
Effect of penicillic acid on adenosine triphosphatase activity in the mouse.

Abstract The effect of penicillic acid on mouse tissue ATPase was examined both in vitro and in vivo . Penicillic acid inhibited in vitro the (Na + , K + )-activated ATPase in the 13,000 g (B) fraction in a dose-dependent manner with calculated I50 values of 2.5 and 3.3 × 10 −5 m for brain and kidney, respectively. Similar inhibition in the microsomal fraction also was observed with I50 values of 6.0 and 1.0 × 10 −5 m for brain and kidney tissues, respectively. Brain and kidney (Na + , K + )-ATPase activity also was inhibited by penicillic acid in vivo . An inhibition time response of (Na + , K + )-stimulated ATPase in brain and kidney tissue from mice receiving 80 mg/kg penicillic acid in saline was noted while a dose-dependent effect was demonstrated in the brain microsomal fraction and in the kidney B and microsomal fractions. Mg 2+ -Activated ATPase activity was not significantly impaired except for oligomycin-insensitive Mg 2+ -ATPase in the brain B fraction. Thus, in vitro and in vivo results suggested a possible correlation between inhibition of (Na + , K + )-ATPase activity and penicillic acid-mediated toxicity.
Mg2+-dependent conformational change of RNA studied by fluorescence correlation and FRET on immobilized single molecules

Fluorescence correlation spectroscopy (FCS) of fluorescence resonant energy transfer (FRET) on immobilized individual fluorophores was used to study the Mg2+-facilitated conformational change of an RNA three-helix junction, a structural element that initiates the folding of the 30S ribosomal subunit. Transitions of the RNA junction between open and folded conformations resulted in fluctuations in fluorescence by FRET. Fluorescence fluctuations occurring between two FRET states on the millisecond time scale were found to be dependent on Mg2+ and Na+ concentrations. Correlation functions of the fluctuations were used to determine transition rates between the two conformations as a function of Mg2+ or Na+ concentration. Both the opening and folding rates were found to vary with changing salt conditions. Assuming specific binding of divalent ions to RNA, the Mg2+ dependence of the observed rates cannot be explained by conformational change induced by Mg2+ binding/unbinding, but is consistent with a model in which the intrinsic conformational change of the RNA junction is altered by uptake of Mg2+ ion(s). This version of FCS/FRET on immobilized single molecules is demonstrated to be a powerful technique in the study of conformational dynamics of biomolecules over time scales ranging from microseconds to seconds.
Comparative metabolism of 2-acetylaminofluorene by rainbow trout and rat liver subcellular fractions

Abstract In order to assess the cause of the resistance of rainbow trout ( Oncorhynchus mykiss ), Shasta strain, to the hepatocarcinogenic effects of 2-acetylaminofluorene (AAF), we have investigated the metabolism of this model chemical by subcellular fractions from trout liver. Treatment of trout with 3-methylcholanthrene (3-MC) enhanced the rate of metabolism of AAF by liver microsomes. The major AAF metabolites produced by trout liver microsomes at saturating substrate concentration (34.3 and 19.5 μM AAF for control and 3-MC-induced microsomes, respectively) were 7-hydroxy-AAF and 5-hydroxy-AAF which represented 75 and 21% of total AAF metabolites, respectively for control microsomes, and 79 and 18% of total metabolites, respectively for induced microsomes. With both control and 3-MC-induced microsomes, N-hydroxy-AAF (the proximate carcinogen of AAF) was a minor metabolite accounting for less than 1% of total AAF metabolites. At a low substrate concentration (0.18 μM AAF), 7-hydroxy-AAF formation accounted for 95 and 91% of total metabolites for control and 3-MC induced microsomes, respectively, and a slight relative increase in N-hydroxy-AAF production (1.5–2.5%) was observed. Liver microsomes from untreated male Sprague-Dawley rats (a species susceptible to hepatocarcinogenesis by AAF) formed N-hydroxy-AAF in greater proportions (14-fold) and ring-hydroxylated metabolites in smaller proportions compared to trout liver microsomes. The activities of cytosolic N-hydroxy-AAF sulfotransferase and acyltransferase in trout liver (24 and 17 pmol/mg h −1 , respectively) were found to be substantially lower than those reported for Sprague-Dawley rats. The low activity of hepatic enzymes implicated in the metabolic activation of AAF (AAF-N-hydroxylase, N-hydroxy-AAF-sulfotransferase, and N-hydroxy-AAF acyltransferase) coupled with a relatively high capacity of the trout liver for ring-hydroxylation (detoxification) of AAF may explain, in part, the resistance of rainbow trout to the hepatocarcinogenic action of AAF.
Equality and Responsive Institutions: Elements of a General Model

In the study of American Government, there have been few ideas more persistent or provocative than the notion that the Constitution was designed to restrict governmental responsiveness. At least since Beard, critics of the American system have argued that widely supported progressive policies are thwarted by the institutional features of Madisonian democracy. Since progressive policies include efforts to make income distribution more equal, advocates of "participative" or "expansive" democracy naturally hypothesize that greater institutional responsiveness will lead to greater social and economic equality. It is argued here that this empirical question cannot be constructively addressed within the conceptual frameworks of either the progressive adherents of such reforms or of most established rational choice perspectives. I construct a model to indicate how the effect of institutional responsiveness on equality depends on the distribution across classes of political participation, the differences between ...
A comparative study of the subcellular binding of phenylmercuric acetate and mercuric acetate in rat liver and kidney slices.

Abstract Studies were made to determine the extent of uptake and the rate of binding of 203Hg-labeled phenylmercuric acetate (PMA) and mercuric acetate (Hg++) in rat kidney and liver slices at 37° and their distribution in subcellular fractions, after incubation in Krebs-Ringer phosphate solutions containing 10−4 M mercurials. The time course of uptake showed that the rat kidney slices rapidly took up both PMA and mercuric ion at the same rate while liver slices incorporated the two mercurials at a much slower rate, with PMA at about twice the rate of mercuric ion. In the study of mercury distribution in subcellular fractions the percentages of PMA or Hg++ bound to mitochondrial and microsomal fractions were low and remained almost constant during a 3-hour experimental period. The bindings of 203Hg from PMA or Hg++ into the nuclear fraction were high and tended to increase as the time of incubation increased, while the 203Hg in the soluble fraction was decreased with the time of incubation. When a comparison was made on the specific binding of mercurials, it revealed that the binding of PMA into mitochondrial, microsomal, and soluble fractions was generally 1.5 to 2 times greater than those of mercuric ion. Only in the nuclear fraction of kidney a greater binding of mercuric ion was noted. This difference in intracellular distribution may be responsible for the different toxicity of PMA and mercuric ion in biological systems.
Three-Dimensional Modeling and Experimental Study of a High Temperature PBI-Based PEM Fuel Cell

This paper investigates the performance of a high temperature proton exchange membrane (PEM) fuel cell. Both experimental work and numerical simulation are conducted. The high temperature proton exchange membrane is based on polybenzimidazole (PBI) doped with phosphoric acid. A single cell with triple serpentine flow channels was operated at steady state at various levels of temperature, pressure, and air stoichiometry. A three-dimensional model was used to simulate the cell performance, and polarization curves were used to validate the experimental values. The theoretical model accurately predicts the experimental results. A sound knowledge of the impact of various variables at various levels of the cell operation is necessary for unraveling the parametric influence and can prove extremely useful for optimizing the cell operation.
Episodic Release of Luteinizing Hormone at Mid-menstrual Cycle in Normal Adult Women

Twelve normal women with regularly recurring menstrual periods had electrophysiological recording performed and indwelling venous catheters inserted during 1–4 consecutive nights of sleep at mid-menstrual cycle. Four of these subjects were also studied during daytime waking activity. Plasma samples were collected at frequent intervals in order to study the temporal aspects of LH secretion. LH was measured by double-antibody radioimmunoassay. All subjects demonstrated episodic secretion of LH at a frequency (for major episodes) which resembled that of the human REM-non-REM sleep cycle. However, there was no correlation of plasma LH values with the stages of sleep. In addition, no difference in LH concentration was found between sleep and waking. During the LH surge, episodic secretion of LH continued and was superimposed on a rising baseline. Two subjects, who were studied sequentially before and during the LH surge, demonstrated sudden elevations of plasma LH concentration in the latter part of the sleep ...
Microfluidic circuits with tunable flow resistances

Microfluidic devices, due to their conveniently small size and the unique physicochemical behavior of fluids in microscale volumes, have become essential tools in many areas of science and technology. Fluid flow in microchannels, microvalves, and micropumps have many parallels with electrical current through wires, switches, and current sources of microelectronic circuits. The equivalent of a variable resistor, however, is still unavailable. Here the authors present addressable microarrays of deformable elements producing sixteen levels of flow resistance. Using a purely resistive electrical circuit analog, they predict the steady-state output of a three-inlet mixer.
Issues in Designing a Policy Language for Distributed Management of IT Infrastructures

The objectives of this paper are twofold. First, we introduce a novel policy language, called CIM-SPL (simple policy language for CIM) that complies with the CIM (common information model) Policy Model and fully incorporates CIM constructs. Currently, the CIM standards from distributed management task force (DMTF) include a policy model, but there is no satisfactory way to render this policy model. CIM-SPL is a language that has been defined for this purpose. Second, we address design and implementation issues for policy languages in general, and for CIM-SPL in particular. The design of CIM-SPL was inspired by our previous experiences in designing various policy languages (e.g., PDL from Bell Laboratories, and ACPL from IBM) and lessons learned from studying other well-known policy languages (e.g., Ponder from Imperial College). We will discuss our design choices, evaluating the pros and cons of various alternatives. The ideas presented in this paper are meant to shed light on our design decisions, and provide guidance for those who want to build a CIM-based policy system or some other policy system in the future.
The IS1167 insertion sequence is a phylogenetically informative marker among isolates of serotype 6B Streptococcus pneumoniae

The phylogenetic utility of the IS1167 insertion sequence was examined with restriction fragment length polymorphism (RFLP) analyses of a sample of 50, predominantly invasive, capsular serotype 6B Streptococcus pneumoniae isolates previously characterized by multilocus enzyme electrophoresis (MLEE). The strains represented a genetically diverse assemblage of 34 distinct clonotypes composed of 26 restriction fragment types and 23 multilocus enzyme types. All isolates carried the IS1167 insertion sequence, with an average of 9.5 copies. The cross-classification of isolates based on RFLP and MLEE typing schemes was 81% concordant. Phylogenetic analyses demonstrated a significant (P < 0.0001) association between strains of a given RFLP lineage with those of a given MLEE lineage. A significant correlation (P < 0.00004) was also found between the proportion of restriction fragments shared by any given pair of isolates and their genetic distances estimated from the MLEE data. Parity between the two genetic markers implied that the sampled isolates were in linkage disequilibrium. The existence of nonrandom associations among genetic loci was confirmed by Monte Carlo analyses of the MLEE data. These studies, thus, demonstrated that invasive pneumococcal isolates of a single capsule type recovered on a regional scale can retain a largely clonal population structure over a period of 8 years. The ability to detect linkage disequilibrium and generate relatively congruent dendrograms based on distance and parsimony methods suggested that the restriction fragment data were robust to phylogenetic analysis.
Theory of dark-state polariton collapses and revivals

We investigate the dynamics of dark-state polaritons in an atomic ensemble with ground-state degeneracy. A signal light pulse may be stored and retrieved from the atomic sample by adiabatic variation of the amplitude of a control field. During the storage process, a magnetic field causes rotation of the atomic hyperfine coherences, leading to collapses and revivals of the dark-state polariton number. These collapses and revivals should be observable in measurements of the retrieved signal field, as a function of storage time and magnetic field orientation.
Magnetic Separation Immunoassay for Digoxin in Plasma with Flow Injection Fluorescence Detection

Immunoassay (IA) is a sensitive and selective approach for low level quantitation of drugs. Magnetic separation immunoassays use magnetic beads to facilitate the separation of bound labeled antigens from free antigens in solution. Digoxin was chosen for this study because low level analysis (ng mL−1) in biological samples isrequired, antibodies to digoxin were commercially available and derivatization procedures for fluorescence labeling were well established. A competitive immunoassay format was used in this study. Streptavidin coated magnetic beads were attached to biotinylated anti-digoxin antibodies for the separation. The inhibition curve for off-line magnetic separation immunoassay of digoxin in spiked plasma was characterized and the dynamic range of the curve was 0.25–2.5 ng mL−1. A power fit weighted by the inverse of concentration was found to provide the best fit to the data (r=0.9934). The percent RSDs for the two controls, 0.8 and 2.2 ng mL−1, were 9.95% and 20.62% (n=6) and the percent errors were 11.75% and 22.63% (n=6), respectively. The limit of detection (LOD) in plasma is 0.14 ng mL−1. The dynamic range of the inhibition curve for on-line magnetic separation immunoassay of digoxin was 0.5–15 ng mL−1 of digoxin. A quadratic fit was found to provide the best fit to the data (r=0.9937). The percent RSDs for the two controls, 4.0 and 12 ng mL−1, were 14.1% and 10.7% (n=6) and the percent errors were 5.8% and 3.3% (n=6) from the spiked value, respectively. The LOD was estimated to be 0.44 ng mL−1 (determined as two times the standard deviation of the blank, n=6). The on-line method has the advantages of being relatively easy to automate in the continuous flow mode and is adaptable for use in conjunction with HPLC separations.
Repetition deficits in three aphasic syndromes

This study examined the repetition errors of three aphasic subgroups during a repetition task. A total of 95 subjects, including 32 conduction, 38 Broca's, and 25 Wernicke's aphasics, repeated phrases and sentences from the Repeating Phrases Subtest of the Boston Diagnostic Aphasia Examination. Conduction aphasics exhibited a greater number of phonemic attempts, word revisions, and word and phrase repetitions. Broca's aphasics demonstrated more phonemic errors and omissions. Finally, Wernicke's aphasics showed more unrelated words and jargon.
Differential and Depreciation Effects of Shared Experience: Evidence from Software Projects

Shared experience (i.e., experience working together) among project team members is known to affect a project team's performance. Yet, little is known of whether the effects of shared experience homogeneous. We empirically find that the effects of shared experience on a project's performance vary by the outcome of shared experience (e.g., successful vs. unsuccessful) as well as project team role (e.g., project managers vs. non-managers) in the context of software development. Moreover, we find the effects of shared experience depreciate over time. Our study has a theoretical contribution by showing differential and depreciation effects of shared experience. It also has practical implications on the project staffing problem.