cssi/SciSciGPT-SciSciNet huggingface dataset:
Ozone in the free atmosphere

The present book provides a summary of the state of scientific knowledge of stratospheric and free tropospheric ozone as it exists at the beginning of 1983. Ozone photochemistry in the stratosphere is discussed, taking into account fundamental molecular properties, the absorption spectrum of ozone, photodissociation, ozone formation and destruction in the upper atmosphere, the photochemistry of odd-hydrogen, the photochemistry of odd-nitrogen, the photochemistry of odd-chlorine, and photochemistry-temperature coupling. The observed distribution of atmospheric ozone and its variations are considered along with ozone transport, ozone in the troposphere, stratospheric ozone perturbations, and climatic and biological effects. Attention is given to the techniques of observing atmospheric ozone, horizontal-vertical ozone transport and conservative quantities, measurements of tropospheric ozone, the tropospheric ozone budget, ozone models, natural ozone variations, and anthropogenic ozone perturbations.
The effect of nitric acid uptake on the deliquescence and efflorescence of binary ammoniated salts in the upper troposphere

[1] Thermodynamic equilibrium model calculations are used to show that HNO3 can lower the relative humidity barrier to deliquesce binary ammoniated salts in the upper troposphere, particularly in aerosol solutions with an (NH4)2SO4 composition. Also in the case of (NH4)2SO4 or NH4HSO4 there is no abrupt change in the physical state of the thermodynamic system (instantaneous change of a dry salt particle into an aqueous solution) at the deliquescent point, which is typical for such a phase transition. Model results show that HNO3 dissolution in ammoniated aerosol solutions can prevent the efflorescence of (NH4)2SO4 and NH4HSO4 salts in favor of (NH4)3H(SO4)2 (letovicite) crystallization. Future laboratory experiments, where binary ammoniated salts are studied at cold temperatures in the presence of both HNO3 and H2O, are needed to confirm the results of our model calculations.
Calcium channels coupled to glutamate release.

Publisher Summary This chapter reviews the current understanding of the properties of presynaptic calcium channels and considers how defects in the channels or their interactions might result in pathological abnormalities. Voltage-gated calcium channels stand as the pivotal regulatory element of excitation–secretion coupling at nerve endings in brain. Recent advancement has resulted in an explosive increase in information about the identity of both the calcium channels and the proteins that comprise the neurosecretory machinery. Analysis of calcium channel gene expression has revealed numerous related genes, each of which with splice variants that, in principle, could amount to impressive combinatorial possibilities. The nerve terminal is of particular importance to neuroscientists, because it is the cellular locus where electrical information is transduced to intercellular chemical messages, and calcium channels play a pivotal role in this transduction. Calcium channels, by virtue of regulating excitation–secretion coupling, provide an attractive target for pharmacological management of neuronal activity.
From Noxious to Public? Tracing Ethical Dynamics of Social Media Platform Conversions

Sometimes, some social media marketplaces turn from noxious to public. Why do such conversions happen, what do they reveal about a platform’s definition of “public,” and when should they happen? Dr...
Wide-Field Infrared Explorer spacecraft system design

Following a formal and competitive process, the Wide-Field Infrared Explorer (WIRE) instrument was selected in 1994 to become a participant in NASA/Goddard Space Flight Center's Small Explorer Program (SMEX). The WIRE instrument will be used to conduct a deep infrared, extra galactic science survey 500 times more sensitive than the Infrared Astronomy Satellite (IRAS) Faint Source Catalog. The WIRE instrument includes a cryogenically cooled (<7.5 K), 128/spl times/128 pixel, long wave, infrared detector embedded within an optical assembly which is cooled by a two-stage, solid-hydrogen cryostat. The WIRE spacecraft is being configured to be placed into a 470/spl times/540 km sun-synchronous orbit using an Orbital Sciences Corporation Pegasus XL launch vehicle. Total spacecraft mass will be less than 275 kg. Orbit average power consumed will be less than 175 W. The WIRE instrument will be delivered to NASA/Goddard Space Flight Center in early 1998 to undergo integration and test with the WIRE spacecraft bus and subsequently will be launched in the fall of 1998. The SMEX program uses a strict design-to-cost approach to manage and to contain overall mission cost. This paper will present the major instrument, operational and cost requirements driving the spacecraft systems design for the mechanical, structural, thermal, attitude control, command and data handling, power and electrical systems. It will document major system trade studies results and the subsequent spacecraft design to meet mission requirements.
An exponential power life-testing distribution

An extreme-value type life-testing distribution is studied which has the property that the hazard function say assume a U-shaped form. Also the hazard function is exponentially increasing on the right. Some general properties of least squares type estimators are discussed for the case of location-scale parameter distributions, and these estimators are applied to the proposed model. Properties of the estimators are studied by Monta Carlo simulation, and procedures for interval estimation and tests of hypotheses for the parameters and reliability are provided. A numerical example is also considered.
The Role of R&D Intensity, Technical Development and Absorptive Capacity in Creating Entrepreneurial Wealth in High Technology Start-Ups

Abstract This study uses 80 newly public pharmaceutical biotechnology companies to explore the relationship between a high technology venture’s R&D intensity, technical capabilities and absorptive capacity and the amount of entrepreneurial wealth created by the venture. A novel measure of absorptive capacity based on co-citation analysis of a firm’s scientific publications is developed and several indicators of technical capabilities are used to develop early and late stage measures of a firm’s technical capabilities. The results provide strong evidence of a positive relationship between a high technology venture’s R&D intensity, late stage technical capabilities and absorptive capacity and the amount of entrepreneurial wealth created by a high technology venture.
Infants' persistence at tasks: Relationships to cognitive functioning and early experience

A technique for measuring one aspect of infants' motivation to master the environment—persistence at tasks—is described. Forty-four 13-month-old infants engaged in persistent, task-directed behaviors about 60% of the time during 11 mastery tasks. As a measure of concurrent validity, persistence during a Bayley examination was rated by another examiner; a moderately high correlation ( r = .48) was found. Significant relationships were also found between persistence at the mastery tasks and Bayley MDI, suggesting considerable intertwining of cognition and motivation in infancy. In a subsample of 25 infants tested at 6 months, significant relationships were found between goal-directedness, an index of directed persistent behavior, and both cognitive functioning and infant competence on the mastery tasks at 13 months. Several aspects of the 6-month environments of these 25 infants, especially maternal kinesthetic and auditory stimulation, maternal responsiveness, and responsiveness of toys were related to persistence and competence at 13 months.
The effect of antenatal dexamethasone on maternal and fetal retinol-binding protein.

Abstract Sixteen rhesus monkeys received 0.1 to 15 mg/kg of antenatal dexamethasone at 132 days' gestation; seven control animals received placebo. At 135 days' gestation they underwent cesarean section, and maternal and fetal serum was assayed for retinol-binding protein. Fetal and maternal concentrations of retinol-binding protein increased after dexamethasone (p
The Penetration of Submerged Round Turbulent Gas Jets in Water

Direct measurements of the interfacial behavior of submerged high speed gas jets with speeds ranging from subsonic to supersonic Mach numbers were performed using high speed digital photography and shadowgraphs. The results indicate that the jets preferentially pinch-off near the axial position which in previous experimental work has been shown to correspond to the location of the maximum streamwise velocity turbulence fluctuations. Using the optical method presented in this paper, the data indicates that the electroresistivity probe technique used by past researchers to quantify the jet penetration into the ambient fluid biases the measurement by up to 30 diameters as the probe cannot identify true jet continuity as opposed to advecting bubbles. We introduce a theoretical jet penetration distance based on a simple force balance of the jet cross-section which compares reasonably well with the measured data. This theoretical jet penetration distance scales with the square of the Froude number and requires an estimation of the jet centerline properties as they evolve downstream of the orifice to accurately predict the pinch-off point. An experimental jet penetration distance is introduced and is defined as the 98.5% contour of the orifice attached gas jet presence over the measurement time.Copyright © 2010 by ASME
Continuous Retrieval of Replicated Data from Heterogeneous Storage Arrays

Replicated declustering techniques reduce response times of disk requests by distributing data among multiple disks and retrieving in parallel. Efficient retrieval of replicated data from multiple disks is a challenging problem, especially for heterogeneous storage architectures receiving continuous disk requests. Existing techniques either do not consider the heterogeneity of the disks or handle the requests in a discrete manner assuming the storage system is idle. In this paper, we focus on continuous retrieval techniques in heterogeneous storage architectures to minimize the response time of disk requests considering waiting time and service time of the requests as well as the execution time of the retrieval algorithm. We investigate multiple trade-offs between these three factors affecting the response time of a disk request and propose a maximum flow based adaptive retrieval strategy. Performance of the proposed and existing continuous retrieval techniques are evaluated using simulations driven by real world traces and various homogeneous and heterogeneous multi-disk storage configurations.
The Sphingosine Kinase-Sphingosine-1-Phosphate Axis Is a Determinant of Mast Cell Function and Anaphylaxis

Summary Sphingosine-1-phosphate, a key mediator in immune cell trafficking, is elevated in the lungs of asthmatic patients and regulates pulmonary epithelium permeability. Stimulation of mast cells by allergens induces two mammalian sphingosine kinases (Sphk1 and Sphk2) to produce sphingosine-1-phosphate (S1P). Little is known about the individual role of these kinases in regulating immune cell function. Here we show that in mast cells, Sphk2 is required for production of S1P, for calcium influx, for activation of protein kinase C, and for cytokine production and degranulation. However, susceptibility to in vivo anaphylaxis is determined both by S1P within the mast cell compartment and by circulating S1P generated by Sphk1 predominantly from a non-mast cell source(s). Thus, sphingosine kinases are determinants of mast cell responsiveness, demonstrating a previously unrecognized relationship with anaphylaxis.
Differences in narrative productions of closed head-injured adults

The purpose of this study was to compare the abilities of 9 high-level, closed head-injured (CHI) adult subjects (M age = 31 years, age range = 20–56 years) utilizing the narrative tasks of storytelling and story generation. Analysis of the language used under the two conditions was found to be similar to that described in a study by Liles, Coelho, Duffy, and Zalagens (1989), which characterized discourse problems observed in four closed head-injured subjects. Findings appeared to indicate that the performances of the subjects on the two narration tasks demonstrated significant differences in length, complexity, and focus of narrations. The described procedure appeared to be a useful method of characterizing the kinds of language deficits displayed by this population of subjects.
Dietary Studies with American Shad Fry

Abstract Studies were conducted to evaluate foods for fry of American shad (Alosa sapidissima) in earthen ponds and outdoor tanks. Fry grew rapidly (more than 100 mg in 4 weeks) in both ponds and tanks when suitable food was available. Live Daphnia magna and D. pulex were excellent food sources. A commercial fry feed for trout and a mixed culture of rotifers and wild Moina sp. also produced acceptable growth. Despite the fact that a considerable amount of phytoplankton was found in the stomach contents, phytoplankton alone did not appear to be a suitable diet for shad fry.
National Medical Care Spending

For the first time since Medicare and Medicaid were implemented, the annual rate of increase for medical care expenditures from 1983 to 1984 was under 10 percent Gerard Anderson of the Johns Hopkins' Center for Hospital Finance and Management examines this and other trends in national medical care spending. Also in this issue, Joseph Valvona and Frank Sloan of Vanderhilt University present data on the rising rates of surgery among the elderly.
Vale Susan Noffke: person holding door

Susan Noffke was a professor in the Department of Curriculum and Instruction at the College of Education at the University of Illinois, Urbana-Champaign from 1993 to 2013. For more than 25 years – ...
Modification of matrix polysaccharides during avocado (Persea americana) fruit ripening: an assessment of the role of Cx-cellulase.

The role of Cx-cellulase (EC 3.2.1.4) in fruit ripening and softening is unknown. In the present study, avocado (Persea americana) fruit, a rich source of Cx-cellulase, were examined to determine if the enzyme plays a role in ripening-related hemicellulose metabolism. Hemicelluloses (4 M alkali-soluble) from avocado fruit exhibited a very broad distribution of polymer sizes and an overall decrease in Mr during ripening. Polymers affected were primarily those of large Mr (relative molecular mass). The characteristic total hemicellulose Mr distribution and changes with ripening were also evident for xyloglucan (XG), a putative substrate for avocado Cx-cellulase. Hydrolytic activity toward hemicelluloses from preripe fruit was detected in crude buffer-soluble protein extracts derived from ripe avocado mesocarp tissue. XG was also degraded, and in a pattern similar to that observed during ripening. Purified Cx-cellulase also exhibited activity against specific components of isolated hemicelluloses; however, in contrast to the crude protein. Cx-cellulase alone was without influence on the Mr distribution of avocado XG. Protein depleted of Cx-cellulase was capable of moderate XG depolymerization. We conclude from the present studies that the enzyme Cx-cellulase is not involved in the ripening-related depolymerization of XG in avocado fruit.
Stable hydrogen isotopes in iron oxides—II. DH variations among natural goethites

Abstract Goethite samples analyzed for this study have a δD range from −202 to −98 per mil with a corresponding δD range of associated waters from about −110 to +7 per mil. Goethites with the most positive δD values are from marine environments. Goethite-water equilibrium D H fractionation factors measured in this laboratory at 100°C and 145°C and estimated for sedimentary temperatures from data on natural samples have values of about 0.900 at all three temperatures. These data suggest that goethite δD values may be a direct, temperature-independent measure of the δD values of the waters with which the goethite last equilibrated. Most of the goethite δD values in this study reflect the δD values of the modern waters in the locales of origin. Substitution of Mn and/or Al for Fe in the goethite structure may affect the mineral-water fractionation factor. Manganese appears to decrease the value of α. The effect of Al substitution on α has not yet been measured, but preliminary arguments suggest that increasing Al content could increase α values.
Regulation of limb development by the sphingosine 1-phosphate receptor S1p1/EDG-1 occurs via the hypoxia/VEGF axis.

Abstract Angiogenesis, also known as new blood vessel formation, is regulated coordinately with other tissue differentiation events during limb development. Although vascular endothelial cell growth factor (VEGF) is important in the regulation of angiogenesis, chondrogenesis and osteogenesis during limb development, the role of other angiogenic factors is not well understood. Sphingosine 1-phosphate, a platelet-derived lipid mediator, regulates angiogenesis and vascular maturation via its action on the G-protein-coupled receptor S1P1 (also known as EDG-1). In addition to vascular defects, abnormal limb development was also observed in S1p1−/− mice. Here we show that strong induction of S1P1 expression is observed in the blood vessels and the interdigital mesenchymal cells during limb development. Deletion of S1P1 results in aberrant chondrocyte condensation and defective digit morphogenesis. Interestingly, the vasculature in the S1p1−/− limbs was hyperplastic and morphologically altered. In addition, the hypoxia inducible factor (HIF)-1α and its response gene VEGF were induced in S1p1−/− limbs. However, aberrant regulation of HIF-1α and VEGF were not observed in embryonic fibroblasts derived from S1p1−/− mice, suggesting a non-cell autonomous effect of S1P1 on VEGF expression. Indeed, similar limb defects were observed in endothelium-specific S1P1 null mice in vivo. These data suggest that the function of S1P1 in the developing vasculature is essential for proper limb development.
Leverage Plots for General Linear Hypotheses

Abstract Leverage plots are a generalization of partial-regression leverage plots, extending the idea to apply to general linear hypothesis tests. Leverage plots can show the point-by-point composition of the sum of squares for a hypothesis test. They are valuable in revealing the degree of fit, the parameter estimates, the residuals, a measure of the variance of the fit, influential points, nonfitting points, nonlinearities, and even collinearity.
A SIMPLIFIED METHOD FOR RADIOIODINE ANALYSIS

Abstract A radiochemical method of analysis for gross iodine activity in the primary coolant of pressurized water reactors has been developed at K.A.P.L. It is based upon the rapid isotopic exchange which occurs under suitable conditions between fission product iodine and the iodine atoms in preformed silver iodide. The principal steps in the procedure are the following: (a) about 20 ml of the slightly basic coolant is oxidized with sodium hypochlorite. Lanthanum hydroxide is formed by adding lanthanum nitrate to the solution, (b) the lanthanum hydroxide scavenger is removed by filtration, (c) the solution is acidified and treated with sodium bisulfite to reduce the iodine to an exchangeable form, (d) the solution is contacted with preformed silver iodide, (e) the silver iodide is removed by filtration, washed, mounted and counted. The procedure has been found to give excellent decontamination from fission products and activated corrosion products which occur in the primary coolant of pressurized water reactors. The recovery of iodine has been shown to be 88 ± 5 per cent. During the past year, the procedure has been used extensively at K.A.P.L. for applications where speed and simplicity are of greater importance than highest accuracy.
Aphid‐induced reduction of shoot and root growth in Douglas‐fir seedlings

1. The short- and long-term effects of photosynthate removal by sapsucking herbivores on plant growth were examined by experimentally manipulating densities of an aphid Cinara pseudotsugae (Wilson) on 2-year-old Douglas-fir seedlings Pseudotsuga menziesii (Mirb.) Franco under greenhouse conditions. An 18-week test was conducted to determine short-term effects. Effects of long-term aphid feeding were examined by exposing seedlings to aphid feeding for two consecutive growing seasons. A third experiment evaluated the extent of recovery during 1 year following a single season of aphid feeding. At least 35 seedlings were used in each test. 2. Volume and dry weight of both shoots and roots decreased significantly with increasing aphid feeding in all three experiments. 3. The most significant and severe aphid effect was reduced root tissue density, suggesting carbohydrate depletion due to translocation from roots to shoots. 4. There was no sign of recovery, of either root or shoot growth, during the year following one season of feeding. 5. The results of this study indicate that short-term feeding by aphids can affect plant growth and structure for a relatively long time.
Social cognition and subclinical paranoid ideation.

Objective. A number of cognitive biases have been identified relevant to persecutory thought (e.g. exaggerated self-serving bias). Moreover, findings of increased depressed mood in conjunction with high levels of self-esteem have contributed to theories of persecutory ideation (e.g. Bentall, Kinderman, Kaney, 1994). Using a nonclinical sample, the present study sought to expand upon previous research by examining the linear relationship between persecutory ideation and multiple clinical and social cognitive variables. Design. A cross-sectional design was used. Correlational and multiple regression analyses were conducted. Method. One hundred and ninety-three undergraduate students were administered a battery of questionnaires which assessed the following domains: Paranoid ideation, depression, social anxiety, self-monitoring, attributional style and self-esteem. Results. Higher levels of paranoid ideation were significantly associated with greater depressed mood, social anxiety and avoidance, evaluation apprehension, self-monitoring and lower self-esteem. There were no significant associations between paranoid ideation and attributional biases. Conclusions. These findings suggest that mood, anxiety and perceptions of the self are related to paranoid ideation in a nonclinical sample. These findings are tempered, however, by studying a nonclinical sample and the self-report measures of paranoid ideation that might be assessing multiple aspects of paranoid thought (e.g. ideas of reference).
A visual analysis of anthropomorphism in the Kabbalah: dissecting the Hebrew alphabet and Sephirotic diagram

A complex series of mystical texts and rituals within medieval Judaism, the Kabbalah endeavors to explain God by contemplating the anthropomorphic traits of designed artefacts - the Hebrew letterfo...
Bayley's infant behavior record ratings of infants with recurrent apnea: behavioral profile and correlates with apnea, age, and developmental status.

ABSTRACTThe goal of this study was to provide a behavioral profile of apneic infants and to examine relationships between behavioral ratings, apnea frequency, age, and concurrent developmental status. Two samples of previously apneic infants were included in this exploratory analysis using the Infan
Private Sector Foreign Investment and the Environment

Summary The industrialization of the developing world is now and will continue to be predominately financed by private capital rather than bilateral or multilateral assistance. To the extent that associated pollution problems spill across national boundaries, this industrialization can no longer be viewed by the developed world as simply an investment opportunity but must also be seen as a potential source of pollution harm. Just as governments have an interest in investments made within their borders, the way in which capital is invested in developing countries has become a legitimate interest of policy makers in developed countries. Governments can advance their international environmental interests by direct assistance, and by providing incentives to the private sector. The private sector can assist in the establishment of environmental guidelines, labelling criteria, and investment guidelines. However, to be effective these mechanisms must be co-ordinated transnationally.
Neurogenic inflammation and the peripheral nervous system in host defense and immunopathology

Although the nervous and immune systems have been classically considered to modulate physiologically distinct functions, recent evidence points to coordinated activities during neurogenic inflammation. In this perspective, the authors examine the interactions between the peripheral nervous system and the immune response during health and disease.
Sequential Lineup Laps and Eyewitness Accuracy

Police practice of double-blind sequential lineups prompts a question about the efficacy of repeated viewings (laps) of the sequential lineup. Two laboratory experiments confirmed the presence of a sequential lap effect: an increase in witness lineup picks from first to second lap, when the culprit was a stranger. The second lap produced more errors than correct identifications. In Experiment 2, lineup diagnosticity was significantly higher for sequential lineup procedures that employed a single versus double laps. Witnesses who elected to view a second lap made significantly more errors than witnesses who chose to stop after one lap or those who were required to view two laps. Witnesses with prior exposure to the culprit did not exhibit a sequential lap effect.
Multi-sigmoidal neural networks and back-propagation

A new neural network architecture based on dynamically created nonmonotonic activation functions that are modeled by a set of sigmoidal functions is introduced. A modification of the backpropagation algorithm is presented that is capable to learn both the weights and the unit activation functions themselves. The new architecture reveals an existing tradeoff in capturing interactions of the inputs via hidden units or nonmonotonic activation functions. In the classification problems examined, the new architecture resulted in very shallow networks with fewer degrees of freedom than the corresponding backpropagation networks. Those networks converged very fast to a solution and resulted in optimal or nearly optimal sigmoidal configurations.
Airburst warning and response

It is virtually certain (probability499%) that the next destructive NEO event will be an airburst. Planetary defense is usually assumed to have the primary goal of maximizing the number of lives saved, but it can be argued that more emphasis should be placed on maximizing the probability of saving lives. For the latter goal, it is far more effective to create an early warning and civil defense plan than a mitigation plan that involves deflecting a large NEO. Because early warning and civil defense will almost certainly be needed long before the first deflection is ever required, the credibility of the planetary defense community and its recommendations will be put to its first serious test by an airburst. Successful response to an airburst event will make it much more likely that recommendations for mitigation by deflection will be accepted by decision makers and the public. Focusing more attention on the second goal will, as a side effect, benefit the primary goal.
The role of ferroelectric domains in PTC thermistors

Abstract The role of ferroelectric domains in positive temperature coefficient of resistivity (PTCR) barium titanate thermistors will be discussed. Domain related phenomena in this class of technologically important material are analyzed in terms of the grain boundary barrier layer model.
Quantification of Dosimetric Impact of Implementation of On-Board Imaging (OBI) for IMRT Treatment of Head-And-Neck Malignancies

Abstract Implementation of daily kilovoltage imaging for setup verification improves the reproducibility of treatment by eliminating small random setup errors. We evaluate the dosimetric consequences of such shifts, not yet evaluated, in a group of head-and-neck cancer patients (ENT) treated with intensity modulated radiation therapy (IMRT) at Emory University. Twelve patients with ENT malignancies were analyzed. On-Board Imaging (OBI) was used in at least 70% of each patient’s treatment sessions. An isodose distribution was generated for each fraction, with the isocenter shifted to its calculated location prior to OBI repositioning. These plans were summed and then compared to the simulation plan for coverage of target structures. For these 12 patients, there were a total of 18 planning target volumes (PTV). The mean (range) percent reduction in minimum dose was 12.1% (−1.0 to 43.3). For 10 right necks and 9 left necks treated, the mean percent reduction in minimum dose was 11.8% (−0.6 to 39.7) and 13.3% (−3.6 to 31.2), respectively. The mean reduction in mean dose to the PTV was 1.3% (0 to 5.1). The mean reduction in mean dose to the right and left necks was 1.0% (0.2 to 3.9) and 1.13% (0.4 to 3.4), respectively. From this analysis, we conclude that the shifts made were small and random, with essentially no change in mean dose delivered to target structures. There is, however, significant improvement in the minimum dose delivered. Underdosing even a small portion of the tumor potentially sacrifices the probability of local control; correcting these setup errors seems desirable.
Penalties of Nonoptimal Turnback Manuevers

Turning back after engine failure during the takeoff phase of flight in a single-engine aircraft is reexamined to determine the penalties for using nonoptimum parameters. The effects of using nonoptimum parameters is least for small variations in initial climb speed increasing when using bank angles less than the optimum 45 deg bank angle and most critical when using higher speeds in the turn. Comparisons with typical general aviation recommendations for lower bank angles and higher speeds in the turn are drawn, all of which are found to be significantly nonoptimal.
Compositional Transient Stability Analysis of Multimachine Power Networks

During the normal operation of a power system, all the voltages and currents are sinusoids with a frequency of 60 Hz in America and parts of Asia or of 50 Hz in the rest of the world. Forcing all the currents and voltages to be sinusoids with the right frequency is one of the most important problems in power systems. This problem is known as the transient stability problem in the power systems literature. The classical models used to study transient stability are based on several implicit assumptions that are violated when transients occur. One such assumption is the use of phasors to study transients. While phasors require sinusoidal waveforms to be well defined, there is no guarantee that waveforms will remain sinusoidal during transients. In this paper, we use energy-based models derived from first principles that are not subject to hard-to-justify classical assumptions. In addition to eliminate assumptions that are known not to hold during transient stages, we derive intuitive conditions ensuring the transient stability of power systems with lossy transmission lines. Furthermore, the conditions for transient stability are compositional in the sense that one infers transient stability of a large power system by checking simple conditions for individual generators.
Dielectric studies of the cure of epoxy matrix systems

Dielectric spectroscopy was used to monitor the curing process of two epoxy resin systems. The basic system (system I) consisted of DGEBA (a difunctional epoxy) and a polyamide in a 50–phr mixture. In addition, a comparative analysis was performed on a high–performance resin system (system II) used primarily in unidirectional composite applications. This system contained TGDDM (a tetrafunctional epoxy) and DDS (a tetrafunctional amine) in a 25–phr mixture. The dielectric data were obtained using a simple yet functional sample cell electrode designed and constructed in the laboratory. For system I, isothermal dielectric data were used to determine apparent activation energies for the temperature range from 22 to 70°C. The data showed that the activation energy was a function of temperature and increased as the temperature of the cure increased. This indicated that the reaction mechanism was also a function of temperature. For system II, data were collected between 140 and 190°C and an overall activation energy for that temperature range was determined. The overall activation energies for both systems, calculated using dielectric spectroscopy, compared favorably to those obtained using differential scanning calorimetry. Also, using a wider frequency range (240 Hz to 2 MHz), Argand diagrams were constructed and modeled with the Cole–Cole empirical equation for systems with a distribution of relaxation times. This justified the calculation of average relaxation times, which could then be related to the bulk physical properties of the polymer, such as viscosity. Modified Argand diagrams, where e″ is plotted against e′ at one frequency as a function of time, were also constructed, which aided in the understanding of the curing processes for these thermosetting systems.
Mode localization and eigenvalue loci veering phenomena in disordered structures

An investigation of the effects of disorder on the modes of vibration of nearly periodic structures is presented. It is shown that, in structures with close eigenvalues, small structural irregularities result in both strong localization of the mode shapes and abrupt veering away, or mutual repulsion, of the loci of the eigenvalues when these are plotted against a parameter representing the disorder in the system. Perturbation methods for the eigenvalue problem are applied to predict the occurrence of strong localization and eigenvalue loci veering, which are shown to be two manifestations of the same phenomenon. Also, perturbation methods that handle the dramatic effects of small disorder are developed to analyze eigenvalue loci veering and strong localization. Two representative disordered nearly periodic structures are studied: a mistuned assembly of coupled oscillators and a multi-span beam with irregular spacing of the supports.
Transport of dietary phenethyl isothiocyanate is mediated by multidrug resistance protein 2 but not P-glycoprotein.

Abstract We demonstrated recently that phenethyl isothiocyanate (PEITC), a potent anticarcinogen present in cruciferous vegetables, inhibited P-glycoprotein (P-gp) and multidrug resistance protein 1 (MRP1) and that MRP1 can transport PEITC and/or its metabolites. In this study, we have examined whether PEITC is transported by P-gp and MRP2, two transporters with high expression in human intestine, liver and kidney. Using 14C-PEITC, no significant difference was observed for the intracellular accumulation of PEITC in human breast cancer MCF-7/sensitive (control) and MCF-7/ADR (P-gp overexpressing) cells at PEITC concentrations of 1, 10 and 50 μM. Moreover, the presence of verapamil or PSC833, two P-gp inhibitors, had no significant effect on the intracellular accumulation of PEITC in P-gp overexpressing MCF-7/ADR and MDA435/LCC6MDR1 cells, indicating that PEITC may not be a substrate for P-gp. In contrast, 14C-PEITC intracellular accumulation in the kidney epithelial MDCK II/MRP2 cells (transfected with human MRP2) was significantly lower than in the wild-type MDCK II/wt cells at PEITC concentrations of 1, 5, 10 and 50 μM. The presence of MK571, an MRP inhibitor, significantly enhanced 14C-PEITC accumulation in MDCK II/MRP2 but not MDCK II/wt cells. Furthermore, depletion of intracellular glutathione (GSH) following treatment with buthionine sulphoximine, an inhibitor of GSH biosynthesis, significantly increased 14C-PEITC intracellular accumulation in a concentration-dependent manner. Transcellular transport studies also demonstrated that depletion of intracellular GSH reduced the mean ratio of basal-to-apical transport to apical-to-basal transport of PEITC in MDCK II/MRP2, but not MDCK II/wt cell monolayers. These results indicate that GSH plays an important role in the MRP2-mediated transport of PEITC. The findings provide new information concerning the interactions between PEITC and membrane transporters and suggest the possibility of PEITC interactions with xenobiotics that are MRP2 substrates.
Comparative anatomy and phylogeny of the cloacae of salamanders (amphibia: Caudata). III. Amphiumidae

Histological descriptions of female and male cloacae are pre- sented for the three species of Amphiuma. Little interspecific variation occurs in either females or males. Females possess numerous spermathecae around the walls of the posterior cloacal tube and anterior cloacal chamber as well as rudimentary vent glands, of uncertain homology, in the caudal end of the cloacal chamber. Ventral glands such as those known from female salamanders in other families are absent, likely a secondary loss in the amphiumid clade. In a female A. tridactylum with large ovarian follicles (5- to 8-mm diameter), the lips of the cloacal orifice are highly cornified, and stored sperm in the spermath- ecae appear in organized bundles, either free in the lumen or with the sperm heads seemingly buried in the spermathecal epithelium. Males possess some gland clusters present in other members of the suborder Salamandroidea (dorsal pelvic glands, vent glands, Kingsbury's glands, anterior ventral glands) but lack others (lateral pelvic glands, posterior ventral glands), resulting in the most plesiomorphic cloacal anatomy in the suborder. However, males possess an autapomorphic gland cluster, called the pit glands, in the posterior wall of the cloacal chamber. The pit glands consist of shallow infoldings of the cloacal epithelium unlike other cloacal glands, which are relatively tubular and elon- gate. The "pits" contain columnar eosinophilic cells that give positive staining reactions for acid mucopolysaccharides and proteins. The salamander family Amphiumidae con- sists of three species of Amphiuma found in the southeastern United States. Amphiumas are elongate salamanders with reduced limbs, and adults retain one external gill slit, a paedomorphic character (Duellman and Trueb, '86). Individuals of two species, Amph- iuma means and A. tridactylum, are large, often in excess of 70-cm snout-vent length (SVL), and are aquatic, while A. pholeter is a dwarf species, 20- to 25-cm SVL, that usually is found burrowing in mucky banks (Conant, '75). Davison (1895) described the gross anat- omy of the cloacae of male and female Amph- iuma means and was the first to provide anatomical evidence for internal fertilization in the family. Kreeger ('42) provided a histo- logical description of the cloaca of female A. tridactylum, but the only such account for male amphiumids is an abstract by Wilson ('41) on the same species. Sever ('91) listed presencelabsence data for 23 cloacal charac- ters in amphiumids and other salamanders, and his cladistic analysis of these characters found that amphiumids possess the most ple- siomorphic cloacal anatomy in the suborder Salamandroidea. This paper presents histo- logical descriptions of amphiumid cloacae in order to extend the observations of Wilson ('41) and Kreeger ('42) and to provide the anatomical basis for the character states used by Sever ('91).
Silon as a sac in the treatment of omphalocele and gastroschisis.

Abstract Four babies with prenatal exposed intestines were treated by creating a temporary sac made from dacron coated with Silastic. This material can be sutured to the fascia of the abdominal wall but at the present time it seems advisable to simply suture the prosthesis to the full thickness of the abdominal wall with no preliminary dissection. The use of gamma globulin, systemic and local antibiotics, and strict sterile precautions in the postoperative period diminish the risk of infection which accounted for one death in the series. The gradual reduction of the viscera by simple compression and ligation of the distal portion of the sac avoids the complications associated with abdominal crowding and seems to allow for earlier normal intestinal alimentation. Steroids have been used, hopefully to reduce the inflammatory state of the intestinal tract allowing for earlier intestinal motility. It is important that the extruded viscera simply be covered at the time of the first operation with little or no reduction. These babies looked well in the immediate postoperative period and had no cardiopulmonary complications. The babies stooled normally by the second to fourth day, but feedings were delayed until the abdominal wall was completely closed. Growth and development have been normal in the survivors.
Mammary tumor development in transplanted hyperplastic alveolar nodules of the mouse.

SummaryNodules from adult C3H/Crgl females produce a high incidence of mammary tumors following transplantation into young females. On the other hand, nodules from two C3H sublines which lack demonstrable biologically active mammary tumor virus (MTV) rarely develop mammary tumors when similarly transplanted. Simple exposure to MTV (achieved by transplanting nodular outgrowth from the MTV-free sublines into MTV-infected C3H/Crgl hosts) does not create tumor potentials in these outgrowths equivalent to those seen in the C3H/Crgl population of nodules. It is concluded that a different population of nodules (with regard to tumor potential) is formed in the absence of the MTV than in its presence.
Sperm competition in the Drosophila female.

Modified BS translocation males were developed at 26.0° C where univalentbearing gametes are recovered with less than half the frequency than at 18.0° C. Upon eclosion the males were stored for definite time periods at either temperature before mating individually to single y free-X females. the transfer cultures of the females show a higher frequency of recovery of univalent-bearing progeny regardless of the temperature or storage treatment of the male. In addition, postmeiotic temperature treatment does not appear to fundamentally alter the overall frequency of recovery of univalent-bearing gametes which is presumably determined by the developmental temperature of the male. A similar trend is observed for matings of y females to single X.YSYL/O males in which the males were developed and stored at 26.0° C; namely, a higher frequency of recovery of attached-XY gametes in the transfer cultures.
Towards an understanding of nonlinearity in scintillator detector materials

It has been known for more than 50 years that the light emitted by a scintillator under high-energy excitation (gamma, alpha, proton) is not always proportional to the amount of absorbed energy. The deviation from the linearity of luminosity versus absorbed energy is known as nonproportionality. In addition to its academic interest, this phenomenon has been considered central for scintillator development due to its implication in the limitation of achievable detector performance. Although non-proportional response was studied intensively during the second part of the 20th century, the understanding of its origin and implications on scintillator performance are mainly qualitative. Research in the 1960s uncovered a correlation between proportional response and ionization density, while in the 1980s nonproportionality was proposed as the main reason of energy resolution deviation from the counting statistics limit. It is only recently that the bridge between qualitative and quantitative understanding has been crossed, mainly driven by the large effort undertaken to discover new high-resolution scintillators. Developing such detector materials prompted efforts to gain a deeper understanding of the microscopic processes involved in scintillation mechanisms and so in nonproportionality. In this manuscript, the phenomenology of past and present understanding of non-proportional response will be reviewed. Based on recent experimental, computational and theoretical works, the relation between nonlinear response and energy resolution degradation will be addressed. Finally, the relation between material parameters and proportionality will be evaluated. These recent works are leading towards a deeper understanding of nonlinearity in scintillator detector materials and should result in the development of new high performance scintillator materials.
Control of Cd concentrations in a coastal diatom by interactions among free ionic Cd, Zn, and Mn in seawater

Cadmium and phosphate concentrations in seawater are closely correlated, suggesting that Cd distributions, like those of PO{sub 4}, are controlled by algal uptake and regeneration. But the factors controlling Cd levels in phytoplankton are poorly known. Experiments in metal ion buffer systems with a coastal diatom Thalassiosira pseudonana revealed that cellular Cd:C ratios within the Cd ion concentration ([Cd{sup 2+}]) range in seawater were generally proportional to [Cd{sup 2+}] and inversely related to concentrations of Zn and Mn ions ([Zn{sup 2+}] and [Mn{sup 2+}]) and specific growth rate. The effects of Mn and Zn reflect cellular uptake of Cd by two inducible transport systems: the Mn system whose capacity (V{sub max}) is enhanced at low [Mn{sup 2+}] and a separate system induced at low cellular zinc. At the low [Zn{sup 2+}] of surface oceanic waters ({le}10{sup {minus}11.0} M), Cd uptake is controlled by this latter system and, therefore, is inversely related to ionic zinc levels. However, at the higher [Zn{sup 2+}] range of coastal waters, Cd uptake by this system is strongly suppressed and Cd instead is taken up by the Mn system; as a result it is inversely related to [Mn{sup 2+}] and largely independent of variations in [Zn{supmore » 2+}]. Because of the suppression of Cd uptake by high [Zn{sup 2+}] and [Mn{sup 2+}] in coastal waters, algal Cd concentrations may be lower in these waters than in the ocean despite the presence of higher coastal [Cd{sup 2+}].« less
Reports of chronic pain in childhood and adolescence among patients at a tertiary care pain clinic.

Abstract Although chronic pain in childhood can last into adulthood, few studies have evaluated the characteristics of adults with chronic pain who report childhood chronic pain. Thus, 1,045 new patients (mean age, 49.5 ± 15.4) at an academic tertiary care pain clinic were prospectively evaluated using validated self-report questionnaires. Patients also responded to questions about childhood pain. We found that almost 17% (n = 176) of adult chronic pain patients reported a history of chronic pain in childhood or adolescence, with close to 80% indicating that the pain in childhood continues today. Adults reporting childhood chronic pain were predominantly female (68%), commonly reported widespread pain (85%), and had almost 3 times the odds of meeting survey criteria for fibromyalgia (odds ratio [OR] = 2.94, 95% confidence interval [CI] = 2.04–4.23) than those denying childhood chronic pain. Similarly, those with childhood pain had twice the odds of having biological relatives with chronic pain (OR = 2.03, 95% CI = 1.39–2.96) and almost 3 times the odds of having relatives with psychiatric illness (OR = 2.85, 95% CI = 1.97–4.11). Lastly, compared to patients who did not report childhood chronic pain, those who did were more likely to use neuropathic descriptors for their pain (OR = 1.82, 95% CI = 1.26–2.64), have slightly worse functional status (B = −2.12, t = −3.10, P = .002), and have increased anxiety (OR = 1.77, 95% CI = 1.24–2.52). Perspective Our study revealed that 1 in 6 adult pain patients reported pain that dated back to childhood or adolescence. In such patients, evidence suggested that their pain was more likely to be widespread, neuropathic in nature, and accompanied by psychological comorbidities and decreased functional status.