cssi/SciSciGPT-SciSciNet huggingface dataset:
The Case for Simultaneous Toxicity Testing at Different Levels of Biological Organization

The structure and organization of hazard evaluation and toxicity testing protocols are discussed. It was concluded that more expensive, sophisticated tests can be carried out more efficiently if the results from simpler toxicity tests are available when the complex tests are designed. Simultaneous testing at different levels of biological organization is supported. The author believes there is no compelling evidence that single-species tests can be used to predict reliable responses at more complex levels of organization. Although tests at higher levels of organization may be expensive, many are less expensive than or comparable in cost to long-term, continuous-flow exposure tests of single species.
Quieting T cells with Slfn2

The mechanisms that enforce T cell quiescence are incompletely understood. Slfn2 has now been identified as another participant in this process, functioning as a critical regulator of T cell– and monocyte-mediated immunity.
Forecasting exposure to volcanic ash based on ash dispersion modeling

A technique has been developed that uses Puff, a volcanic ash transport and dispersion (VATD) model, to forecast the relative exposure of aircraft and ground facilities to ash from a volcanic eruption. VATD models couple numerical weather prediction (NWP) data with physical descriptions of the initial eruptive plume, atmospheric dispersion, and settling of ash particles. Three distinct examples of variations on the technique are given using ERA-40 archived reanalysis NWP data. The Feb. 2000 NASA DC-8 event involving an eruption of Hekla volcano, Iceland is first used for analyzing a single flight. Results corroborate previous analyses that conclude the aircraft did encounter a diffuse cloud of volcanic origin, and indicate exposure within a factor of 10 compared to measurements made on the flight. The sensitivity of the technique to dispersion physics is demonstrated. The Feb. 2001 eruption of Mt. Cleveland, Alaska is used as a second example to demonstrate how this technique can be utilized to quickly assess the potential exposure of a multitude of aircraft during and soon after an event. Using flight tracking data from over 40,000 routes over three days, several flights that may have encountered low concentrations of ash were identified, and the exposure calculated. Relative changes in the quantity of exposure when the eruption duration is varied are discussed, and no clear trend is evident as the exposure increased for some flights and decreased for others. A third application of this technique is demonstrated by forecasting the near-surface airborne concentrations of ash that the cities of Yakima Washington, Boise Idaho, and Kelowna British Columbia might have experienced from an eruption of Mt. St. Helens anytime during the year 2000. Results indicate that proximity to the source does not accurately determine the potential hazard. Although an eruption did not occur during this time, the results serve as a demonstration of how existing cities or potential locations of research facilities or military bases can be assessed for susceptibility to hazardous and unhealthy concentrations of ash and other volcanic gases.
Protein catabolism in suckling and fasting northern elephant seal pups (Mirounga angustirostris)

Nursing elephant seal pups are hypothesized to be preadapted to the postweaning fast, yet no comparison of lipid or protein use for meeting metabolic costs has been made between these contrasting nutritional periods. To address this, protein catabolism was estimated in five elephant seal pups from measurements of urea turnover made twice during nursing and twice during the postweaning fast. Changes in body composition were measured in ten separate weaned pups via tritiated water dilution and matched to fasting urea turnover measurements in order to assess errors in protein catabolism derived from urea turnover rates. Estimates of lean mass loss based upon urea turnover and tritiated water dilution were in general agreement, supporting estimates of protein catabolism derived from urea turnover measurements. Protein catabolism was estimated to contribute less than 4% to the average metabolic rate of suckling and fasting pups implying strict protein conservation during both periods and supporting the hypothesis that suckling pups are preadapted to fasting. It is proposed that strict protein conservation across suckling and fasting compensates for relative reductions in maternal investment associated with the abbreviated lactation period of the elephant seal.
Lying to the Future

We don't really have an organized industry until we have a model for the typical; then we may cast the future into the mold of the present. The Web extra at http://youtu.be/ov5qZ7xeR-E is an audio recording in which author David Alan Grier discusses how we don't really have an organized industry until we have a model for the typical.
DEVELOPMENT OF CREATIVE TALENT: PORTRAIT OF AN ARTIST AS A MIDDLE-AGED MAN '

Summary.-This article examined environmental factors contributing to the development of artistic talent. The subject is a 56-yr.-old internationally acclaimed ceramic artist. Interviews with the artist, his family, students, colleagues, and acquaintances provided the main source OF data; records, tapes of lectures, photographs, and actual artistic products yielded additional information. The subject was the product of a warm, stable, achievement-oriented home atmosphere where little attention was paid to the arts. His early association with a culturally enriched family, his urban environment, his propitious university experience, and his personal ambition-all contributed to the full realization of his abilities. Gifted in the areas of music, sports, and drawing, he experienced a crystallizing experience at the age of 17 which set the course of Further creative productivity. The findings are consistent with prior views expressed by Ammons and Ammons in 1962, by Bloom in 1985 and by Walker in 1986. Research is needed to describe the environmental antecedents of creative productivity, especially the uniqueness exhibited in the earlier lives of persons of outstanding ability. This study is in the tradition of the literature which addresses the question stated in the monumental work of Cox (1926): "Given equally 'high abilities,' what conditions of nurture will accelerate the development of these abihties to the point of the highest achievement possible, and what conditions will retard it so that neither that point nor yet the minimum for 'eminence' will be reached?" (p. 13). The investigation presented here examines the development of creativity of one in ceramic art. Attention is upon creative achievement, rather than potential or process. The subject is a 56-yr.-old internationally recognized artist whose creative productivity is well established. How he achieved this eminence is the focus of this paper. Foster (1986) noted that research on the gifted and talented has usually employed large samples, resulting in generalizations about which we could be reasonably confident. However, he believed that the aim of research should not necessarily be such generalization, especially in studies of development of talent. Single-subject studies are the best way to glean knowledge about the idiosyncratic character of giftedness. The nature of exceptionality implies accounting for the unusual and the unique. There is a recent useful distinction among the terms creativity, giftedness, and talent. Young (1985) defines creativity as the skill of bringing about
RNAi-based biosynthetic pathway screens to identify in vivo functions of non-nucleic acid–based metabolites such as lipids

This protocol uses RNAi-based biosynthetic pathway screens combined with genetic and biochemical analyses to identify the functions of non-nucleic acid-based metabolites such as lipids beyond their roles in metabolism.
Atmospheric deposition of nitrogen, sulfur and base cations in jack pine stands in the Athabasca Oil Sands Region, Alberta, Canada

Atmospheric deposition in the Athabasca Oil Sands Region decreased exponentially with distance from the industrial center. Throughfall deposition (kg ha−1 yr−1) of NH4–N (.8–14.7) was double that of NO3–N (.3–6.7), while SO4–S ranged from 2.5 to 23.7. Gaseous pollutants (NO2, HNO3, NH3, SO2) are important drivers of atmospheric deposition but weak correlations between gaseous pollutants and deposition suggest that particulate deposition is also important. The deposition (eq ha−1) of base cations (Ca + Mg + Na) across the sampling network was highly similar to N + S deposition, suggesting that acidic deposition is neutralized by base cation deposition and that eutrophication impacts from excess N may be of greater concern than acidification. Emissions from a large forest fire in summer 2011 were most prominently reflected in increased concentrations of HNO3 and throughfall deposition of SO4–S at some sites. Deposition of NO3–N also increased as did NH4–N deposition to a lesser degree.
Compiler-assisted synthesis of algorithm-based checking in multiprocessors

The task of synthesizing algorithm-based checking techniques for general applications is investigated. The problem is approached at the compiler level by identifying linear transformations in Fortran DO loops and restructuring program statements to convert nonlinear transformations to linear ones. System-level checks based on this property are proposed. The approach is demonstrated with example problems of matrix multiplication and the LINPACK routine: DGEFA. >
Balancing the astigmatic fields when all other aberrations are absent.

When all aberrations are absent other than third-order astigmatism and Petzval, it is demonstrated that selection of a flat tangential astigmatic field is optimum if the smallest maximum spot size is desired over the entire field of view. With balanced sagittal and tangential fields the spot size is observed to be smaller than the flat-tangential-field case until the field angle reaches √⅔ of the full-field angle. Comparisons of the spot sizes and shapes for these cases and the flat-sagittal-field case are made for flat and optimally curved image surfaces.
Do Ethnic Groups Retain Homogenous Preferences in African Politics? Evidence from Sierra Leone and Liberia

It is frequently argued that ethnic groups across Africa retain homogenous preferences stemming from a sense of collective identity and shared destiny, and that they unvaryingly prefer the same outcomes in zero-sum competitions for scarce resources. This article presents results from comparative field surveys examining these claims in Sierra Leone and Liberia following postconflict elections. In contradiction with conventional expectations, the results show corroboration on several issues across voters from several ethnic groups as well as heterogeneity in preferences among voters from the same ethnic groups in both countries. The implications for democratization and conflict resolution in Africa are discussed. E-mail: fbatty@colgate.edu Resume: On avance souvent que les groupes ethniques a travers l'Afrique conservent des preferences d'homogeneite provenant d'un sens d'identite collective et d'une destinee partagee, et qu'ils favorisent les memes opinions dans la concurrence pour les ressources limitees. Cet article presente les resultats de sondages comparatifs mettant en question ces affirmations en Sierra Leone et au Liberia, a la suite du vote d'elections apres un conflit. Contre toute attente, les resultats montrent un esprit de collaboration sur plusieurs questions entre les membres d'ethnies differentes, ainsi que des differences d'opinion entre les membres des memes ethnies, dans les deux pays. Cet article aborde les implications de la democratisation et des processus de resolution des conflits en Afrique.
Definition of inseparably fused ventricular myocardium in thoracopagus: fetal echocardiographic utility and pathologic refinement.

Correlative echocardiographic and pathological findings in a thoracopagus with conjoined hearts are reported. One twin had tricuspid atresia with discordant atrioventricular connections and concordant ventriculoarterial connections. The morphologic right ventricle was hypoplastic and there was a large muscular ventricular septal defect. The other twin had hypoplasia of the mitral valve anulus and left ventricle with double-outlet right ventricle and pulmonary valve atresia. The tricuspid valve was severely insufficient in part because of a large orifice and redundant, elongated leaflets with abnormal chordal attachments. The left ventricles of these two twins shared a perforated common “free wall” with at least two large defects allowing mixing of the circulations at that level. Not all anatomic details were established conclusively by fetal echocardiography; however, sufficient diagnostic information was obtained to support a decision not to aggressively resuscitate these twins after elective cesarean delivery at 31 weeks' gestation.
Magnetic resonance imaging investigation of axonal remodeling and angiogenesis after embolic stroke in sildenafil-treated rats.

Interaction between angiogenesis and axonal remodeling after stroke was dynamically investigated by MRI in rats with or without sildenafil treatments. Male Wistar rats were subjected to embolic stroke and treated daily with saline (n=10) or with sildenafil (n=11) initiated at 24 h and subsequently for 7 days after onset of ischemia. T2*-weighted imaging, cerebral blood flow (CBF), and diffusion tensor imaging (DTI) measurements were performed from 24 h to 6 weeks after embolization. T2* and fractional anisotropy (FA) maps detected angiogenesis and axonal remodeling after stroke, respectively, starting from 1 week in sildenafil-treated rats. Areas demarcated by MRI with enhanced angiogenesis, elevated local CBF, and augmented axonal remodeling were spatially and temporally matched, and FA values were significantly correlated with the corresponding CBF values (R=0.66, P<4 × 10−5) at 6 weeks after stroke. Axonal projections were reorganized along the ischemic boundary after stroke. These MRI measurements, confirmed by histology, showed that sildenafil treatment simultaneously enhanced angiogenesis and axonal remodeling, which were MRI detectable starting from 1 week after stroke in rats. The spatial and temporal consistency of MRI metrics and the correlation between FA and local CBF suggest that angiogenesis, by elevating local CBF, promotes axonal remodeling after stroke.
An improved aerosol generator.

An aerosolizer has been developed which automatically compensates for changes in the concentration and volume of a solution during aerosolization by adjustment of the temperature and pressure of the atomizing air jet. It represents the redesign of a generator previously used for short-term inhalation exposures (one-half to a few hours) where variability in solution concentration was not of great concern and solutions could be replenished daily. The stability of the original generator was quite inadequate, and it was not satisfactory for production of aerosols of constant physical characteristics over longer or repetitive time periods or where a minimum of manipulation is required—viz., for radioactive and other highly noxious materials. The redesigned aerosolizer should be valuable for long-term or repetitive use, since it requires no cleaning, merely refilling, and can be made as small or as large as experimental needs require. It should be particularly useful where correlations between the amount of dep...
Creep, stress relaxation, and plastic deformation in Sn-Ag and Sn-Zn eutectic solders

Because of the high homologous operation temperature of solders used in electronic devices, time and temperature dependent relaxation and creep processes affect their mechanical behavior. In this paper, two eutectic lead-free solders (96.5Sn-3.5Ag and 91Sn-9Zn) are investigated for their creep and stress relaxation behavior. The creep tests were done in load-control with initial stresses in the range of 10-22 MPa at two temperatures, 25 and 80°C. The stress relaxation tests were performed under constant-strain conditions with strains in the range of 0.3-2.4% and at 25 and 80°C. Since creep/relaxation processes are active even during monotonie tensile tests at ambient temperatures, stress-strain curves at different temperatures and strain rates provide insight into these processes. Activation energies obtained from the monotonic tensile, stress relaxation, and creep tests are compared and discussed in light of the governing mechanisms. These data along with creep exponents, strain rate sensitivities and damage mechanisms are useful for aiding the modeling of solder interconnects for reliability and lifetime prediction. Constitutive modeling for creep and stress relaxation behavior was done using a formulation based on unified creep plasticity theory which has been previously employed in the modeling of high temperature superalloys with satisfactory results.
A mathematical model for retrospective impression formation of small group interaction

Abstract We assume that a group member’s summary impressions of the others in a group are a function of their behavior during a session of interaction, plus a possible “bias” component. Data are collected by observers scoring acts in a session of interaction. Regard observers’ reactions to be surrogates for the group members, who retrospectively record their impressions of the others in terms of the same scoring categories. We argue that functions that transform the observers’ data to approximate each group member’s retrospective ratings lie in a five-parameter class of formulae. We discuss possible social–psychological meaning of the parameter values.
Flexure Mounts For High-Resolution Optical Elements

Flexures are passive mechanical-structural devices used to isolate optical elements from the mechanical and thermal effects of the structural support system in such a way that these effects on optical instrument quality are minimized. Mechanical effects include gravity, and inertial and vibratory loadings, as well as possible stresses resulting from assembly errors. Thermal effects include both steady-state and transient environments. For example, if an optical device, with a mirror or lens having a coefficient of thermal expansion orders of magnitude less than that of the material of the support structure (e.g., steel or aluminum), is assembled at a given temperature but operates in a thermally different environment, the optical quality of the instrument may degrade very significantly unless the mirror or lens is isolated from the thermal strain of the support structure. Normally, the mechanical precision of the mount is much less than the precision of the optical surface of the element. If the optical element is rigidly clamped to the mount, this lack of precision in the mount may distort the optical element, and degrade the optical quality of the element.
Dynamics of up-conversion for photoexcited pairs of Er3+ ions in CsCdBr3 crystals

Abstract Pulsed excitation of Er 3+ -doped CsCdBr 3 crystals at 547.5 nm produces observable fluorescences at 338 and 385 nm which are attributable to up-conversion from interacting pairs of excited Er 3+ ions. The decay curves from the blue-shifted emissions show a well-resolved rise and fall. Analysis of the curves indicates that the relaxation of the excited pairs which appears to be largely due to energy transfer processes has a 25 to 30 μs lifetime at both 77 and 300 K. There are significant differences between the up-conversion fluorescence observed under pulsed excitation and that previously reported for continuous excitation.
Converging Technologies: A Critical Analysis of Cognitive Enhancement for Public Policy Application

This paper investigates cognitive enhancement, specifically biological cognitive enhancement (BCE), as a converging technology, and its implications for public policy. With an increasing rate of technological advancements, the legal, social, and economic frameworks lag behind the scientific advancements that they support. This lag poses significant challenges for policymakers if it is not dealt with sufficiently within the right analytical context. Therefore, the driving question behind this paper is, “What contingencies inform the advancement of biological cognitive enhancement, and what would society look like under this set of assumptions?” The paper is divided into five components: (1) defining the current policy context for BCEs, (2) analyzing the current social and economic outcomes to BCEs, (3) investigating the context of cost-benefit arguments in relation to BCEs, (4) proposing an analytical model for evaluating contingencies for BCE development, and (5) evaluating a simulated policy, social, technological, and economic context given the contingencies. In order to manage the risk and uncertainty inherent in technological change, BCEs’ drivers must be scrutinized and evaluated.
Propagation features of cylindrical waveguides with thin chiral coatings

Abstract The propagation behavior of a circular waveguide with a thin internal coating of chiral material is studied. Numerical results for the phase constant as a function of the outer radius, coating thickness and chiral admittance are presented for the modes with azimuth indices of ± 1 and 0.
On the diffusion of an axial load from an infinite cylindrical bar embedded in an elastic medium

his investigation is concerned with the decay of the resultant axial force in an infinite cylindrical elastic bar that is completely bonded to an all around infinite elastic medium of distinct mechanical properties. The bar is subjected to an axial loading confined to, and uniformly distributed over, one of its cross-sections. First, a solution to this problem, exact within classical three-dimensional elastostatics, is obtained for the special case of a circular cylindrical bar. Next, an approximative solution scheme applicable to a cross-section of arbitrary shape is developed. This scheme is subsequently used to deduce an approximate solution for the bar of circular cross-section. The exact and the approximate solution appropriate to the circular bar are compared with each other, particular attention being given to their asymptotic behavior near the load and at large distances from the applied loading. The present work is preliminary to an approximate treatment of the physically more important problem pertaining to The diffusion of load from a transverse tension-bar that is immersed to a finite depth in an elastic halfspace. In addition, the results established here are of interest in connection with the study of fiber-reinforced materials.
Using space-time grid for efficient management of moving objects

Efficient storage and retrieval of moving objects in DBMS have received significant interest recently. There are applications that would benefit from the management of dynamically changing information about moving objects. In this paper, we develop a system that manages such information interacting with moving objects. We model the space-time domain space as a grid (Space-Time Grid) and model the trajectory of a moving object as a polyline in the Space-Time Grid. The polyline is the result of the interactions among other moving objects. In this paper, the insertion algorithm and several other query processing algorithms are presented.
Relaxation dynamics in the first excited singlet state of a cyanine dye: HITC

The S1 state relaxation dynamics of HITC were examined with 200 fs time resolution. The sample was excited at 780, 700, 650 or 600 nm, and the transmission at 780 nm was recorded. In the nondegenerate experiments there is an instantaneous ground state depletion and a stimulated emission signal with a bi-exponential rise with time constants of 300 ± 100 fs and 2.9 ± 0.3 ps. The degenerate experiments show the ground state depletion component and a small stimulated emission signal with a 1.1 ± 0.2 ps decay. The dynamics are assigned to vibrational relaxation and/or solvation effects.
Mechanism of Action of Phenolic Disinfectants III: Uptake of Phenol-C-14, 2,4-Dichlorophenol-C-14, and p-tert- Amylphenol-C-14 by Escherichia Coli

Cell suspensions of Escherichia coli ATCC 11229 were incubated with phenol-C 14 (P-C 14 ), 2,4-dichlorophenol-C 14 (DCP-C 14 ), or p-tert -amylphenol-C 14 (PTAP-C 14 ); radioactivity of the cells was determined. In general, the amount of a phenol associated with the cells increased directly with concentration of the phenol. Increasing the pH between 4.8 and 10 did not significantly affect the radioactivity of the cells incubated with P-C 14 or PTAP-C 14 , but decreased the activity of cells incubated with DCP-C 14 . Temperature had no marked effect on labeling of the cells, and kinetic data indicated that the cells became labeled to the maximum extent very rapidly. The activity of P-C 14 labeled cells was almost entirely extractable by saline-buffer at 22°. Activity from cells incubated with DCP-C 14 and PTAP-C 14 could be partially extracted with saline-buffer at 22°, more activity was extractable in a boiling water bath, and most of the activity was extractable with 70 per cent ethanol at 70°. Polysorbate 80 in a concentration of 1 per cent markedly reduced labeling of cells with DCP-C 14 and PTAP-C 14 and extracted much of the activity from labeled cells, the effect being greater with the latter phenol. These findings suggest that the phenols partition themselves between the aqueous medium and cellular lipids.
Instruction on the Go: Reaching out to Students from the Academic Library.

The purpose of this paper is to describe how a series of one-shot or single class library instruction webinars were created for on-campus and distance education students at Virginia Tech, a land grant institution in rural southwestern Virginia. Virginia Tech's distance learning department on campus trained in Centra 7.6 software and the lead librarian collaborated with peer librarians to offer a wide range of instructional sessions. In this study, interviews were conducted one-on-one with five webinar participants at Virginia Tech. Interviews were digitally audio-taped and transcribed. These interviews were used to gain feedback and information regarding the library-based webinars. Results were organized into thematic codes using NVivo 10 software. Results showed strong interest in the library webinars, especially in the playback or archiving features and interactivity.
Factors Influencing Early Stages of Compaction of Clays and Sands--Review: ABSTRACT

Variations in the water content and fabric of clay, and the porosity of sand during compaction under pressures of 0-100 kg./cm.2 reflect the influence of sediment texture and composition, and are not related uniquely to increases in overburden load. The porosity and water content of sand, silt, and clay under these pressures are inversely related to particle size. This relation commonly is strong enough to obscure the expected decrease in porosity with increasing depth of burial. Variations in the water content of saturated clay reflect the physico-chemical influences on the sorption of water on the surfaces of clay minerals. Water content and surface area per unit mass in the common clay minerals increase in the order kaolinite-illite-montmorillonite. In montmorillonite, at pressures less than 50 kg./cm.2, the water content changes with the exchangeable cation--Na-montmorillonite holds more water than montmorillonite whose exchange positions are filled with Ca, Mg, K, or Al. Increasing concentrations of interstitial electrolyte tend to increase the water content of most clay at a given pressure less than 50 kg./cm.2, presumably by increasing the tendency of the clay particles to form open-work flocculated aggregates that resist compactio . The main exception to this is in very fine-grained clay saturated with Na electrolytes in concentrations less than 0.3 molar. Most of the development of preferred orientation in clay compacted under pressures of 0-100 kg./cm.2 takes place very early--at pressures near 1 kg./cm.2 The most critical factor for this development may be the amount of water held by the clay. If enough water is present, the particles may slip past one another into preferred positions; if not, preferred orientation may be either poorly developed End_Page 626------------------------------ or absent. Large amounts of carbonaceous matter seem to enhance the development of preferred orientation, perhaps by its ability to retain large amounts of water. Specific effects of other factors on clay fabric are less well known, but one might expect the development of preferred orientation to be enhanced by decreasing concentrations of interstitial electrolytes, decreasing valence of exchangeable cations, and decreasing acidity. The main influences on the porosity of sand are the textural characteristics of the constituent particles: size, sorting, roundness, shape, and flexibility. Well-sorted sand has greater porosity than poorly sorted sand. Angular sand has greater initial porosity and is more compressible than rounded sand of the same size. Admixtures of platy mica particles increase the porosity, compressibility, and elasticity of sand. The influence of most of these factors--except for particle size--is inferred from laboratory experiments on simple systems. Little is known of their relative importance in complex natural sediments. End_of_Article - Last_Page 627------------
Removal of organic acids from EfOM using anion exchange resins and consequent reduction of fouling in UF and MF

Abstract The objective was to evaluate anion exchange (IEX) resins to remove organic acids and thus reduce fouling in low-pressure membrane filtration. A secondary objective was to demonstrate the usefulness of a new fractionation strategy for identifying the organic components of wastewater effluent organic matter (EfOM). We previously showed that organic acids (14–60% of EfOM) caused almost all short-term fouling in polyethersulfone (PES) UF. Investigators using different fractionation strategies (without strict removal of colloids and with dramatic pH changes during fractionation) reported that the hydrophilic base/neutral fraction of EfOM was the most important foulant, but colloids were present or had formed in that fraction during processing. In this work we report that resistance to filtration was partially reduced with removal of colloids but nearly all short-term fouling was eliminated with removal of organic acids for PES-UF and for polyvinylidene fluoride (PVDF) MF. Critical flux was increased from 75 to 200 L m −2 h −1 after fixed-bed treatment with weak-base DEAE or strong-base MIEX. Strong-base IRA-958 or non-ionic DAX-8 in column operation, or MIEX with in-line addition, were less effective in reducing fouling and increasing critical flux. These results confirmed our earlier observation that organic acids were primarily responsible for short-term fouling from EfOM and also demonstrated that IEX was effective for removal of organic acids, reducing fouling, and increasing critical flux.
Electrocardiographic Changes Following Balloon Dilatation of Valvar Pulmonic Stenosis

The purpose of this paper was to study the electrocardiographic changes following balloon pulmonary valvuloplasty for pulmonic stenosis and to see if such changes reflect improvement in pulmonary valve gradient following balloon valvuloplasty. Forty-one patients, ages 7 days to 20 years, underwent balloon valvuloplasty for severe valvar pulmonic stenosis. In 35 of these patients ECGs were available 3 to 34 months (mean 11) following valvuloplasty and were compared with pre-valvu-loplasty electrocardiograms. In 30 children with excellent relief of pulmonic stenosis (group I), frontal plane mean QRS vector moved toward the left from 127 ±25° to 81 ±47°as did the horizontal plane mean QRS vector, 88 ± 36° to 27 ±51°. The amplitude of R wave in V1, 19 ± 11.6 mm, and V2, 19.7 ± 12.2 mm, decreased respectively to 9.5 ± 5.9 mm and 11.3 ±6.1 mm. S wave amplitude in V5 and V6 also decreased. The improvement in the electrocardiogram is associated with a decrease in pulmonary valve gradient from 95 ± 50 to 29 ± 23 mm Hg. In five children with significant residual pulmonary valve gradient (group II), the electrocardiograms did not show any significant change. Evaluation of the time course of ECG changes in group I revealed that recognizable electrocardiographic improvement was first observed at 6 months following successful balloon pulmonary valvuloplasty. Normal electrocardiogram suggests minimal residual pulmonary valve gradient while right ventricular hypertrophy suggests significant residual obstruction unless the electrocardiogram was recorded at or before six months following balloon valvuloplasty. These data suggest that electrocardiogram is a good indicator of improvement following balloon pulmonary valvuloplasty. (J. Interven Cardiol 1988:1:3)
Dimensions of Students' Behavior Disorders: An Alternative to Medical Model Classification Practices.

Traditional medical oriented classification schemes have been criticized for their limited reliability and validity. The major deficiency of these approaches is their failure to produce treatment-relevant information. This paper discusses an alternative approach to classifying students' behavior disorders. The approach considers the topography of deviant behaviors, the degree of exceptionality, the nature of deviance, and events influencing the deviance. The proposed approach is discussed in the context of developing and monitoring education/treatment programs.
Molecular dynamics simulations of model trans-membrane peptides in lipid bilayers : A systematic investigation of hydrophobic mismatch

Hydrophobic mismatch, which is the difference between the hydrophobic length of trans-membrane segments of a protein and the hydrophobic width of the surrounding lipid bilayer, is known to play a role in membrane protein function. We have performed molecular dynamics simulations of trans-membrane KALP peptides (sequence: GKK(LA)nLKKA) in phospholipid bilayers to investigate hydrophobic mismatch alleviation mechanisms. By varying systematically the length of the peptide (KALP15, KALP19, KALP23, KALP27, and KALP31) and the lipid hydrophobic length (DLPC, DMPC, and DPPC), a wide range of mismatch conditions were studied. Simulations of durations of 50-200 ns show that under positive mismatch, the system alleviates the mismatch predominantly by tilting the peptide and to a smaller extent by increased lipid ordering in the immediate vicinity of the peptide. Under negative mismatch, alleviation takes place by a combination of local bilayer bending and the snorkeling of the lysine residues of the peptide. Simulations performed at a higher peptide/lipid molar ratio (1:25) reveal slower dynamics of both the peptide and lipid relative to those at a lower peptide/lipid ratio (1:128). The lysine residues have favorable interactions with specific oxygen atoms of the phospholipid headgroups, indicating the preferred localization of these residues at the lipid/water interface.
Virulent and avirulent strains of equine arteritis virus induce different quantities of TNF-α and other proinflammatory cytokines in alveolar and blood-derived equine macrophages

Equine arteritis virus (EAV) infects endothelial cells (ECs) and macrophages in horses, and many of the clinical manifestations of equine viral arteritis (EVA) reflect vascular injury. To further evaluate the potential role of EAV-induced, macrophage-derived cytokines in the pathogenesis of EVA, we infected cultured equine alveolar macrophages (AMphi), blood monocyte-derived macrophages (BMphi), and pulmonary artery ECs with either a virulent (KY84) or an avirulent (CA95) strain of EAV. EAV infection of equine AMphi, BMphi, and ECs resulted in their activation with increased transcription of genes encoding proinflammatory mediators, including interleukin (IL)-1beta, IL-6, IL-8, and tumor necrosis factor (TNF)-alpha. Furthermore, the virulent KY84 strain of EAV induced significantly higher levels of mRNA encoding proinflammatory cytokines in infected AMphi and BMphi than did the avirulent CA95 strain. Treatment of equine ECs with the culture supernatants of EAV-infected AMphi and BMphi also resulted in EC activation with cell surface expression of E-selectin, whereas infection of ECs with purified EAV alone caused only minimal expression of E-selectin. The presence of TNF-alpha in the culture supernatants of EAV-infected equine AMphi, BMphi, and ECs was confirmed by bioassay, and the virulent KY84 strain of EAV induced significantly more TNF-alpha in all cell types than did the avirulent CA95 strain. Thus, the data indicate that EAV-induced, macrophage-derived cytokines may contribute to the pathogenesis of EVA in horses, and that the magnitude of the cytokine response of equine AMphi, BMphi, and ECs to EAV infection reflects the virulence of the infecting virus strain.
Woman's autobiographical writings: New forms

(1985). Woman's autobiographical writings: New forms. Prose Studies: Vol. 8, Modern Selves Essay on Modern British and American Autobiography, pp. 14-28.
Multicomputer Networks: Message-Based Parallel Processing

High-performance message-based supercomputers have only recently emerged from the research laboratory. The commercial manufacturing of such products as the Intel iPSC, the Ametek s/14, the NCUBE/ten, and the FPS T Series - all based on multicomputer network technology - has sparked lively interest in high-performance computation, and particularly in the message-passing paradigm for parallel computation.This book makes readily available information on many aspects of the design and use of multicomputer networks, including machine organization, system software, and application programs. It provides an introduction to the field for students and researchers and a survey of important recent results for practicing engineers. The emphasis throughout is on design principles and techniques; however, there are also descriptions and comparison of research and commercial machines and case studies of specific applications."Multicomputer Networks" covers such major design areas as communication hardware, operating systems, fault tolerance, algorithms, and the selection of network topologies. The authors present results in each of these areas, emphasizing analytic models of interconnection networks, VLSI constraints and communication, communication paradigms and hardware support, multicomputer operating systems, and applications for distributed simulation and for partial differential equations. They survey the hardware designs and the available software and present a comparative performance study of existing machines.
SYNOVIAL SARCOMA METASTATIC TO THE PENIS AND PROSTATE

Synovial sarcoma is the fourth most common of all soft tissue sarcomas. Its typical presentation is in the paraarticular soft tissues of the lower extremities in young adults. We report a case of sarcoma initially discovered near the spine that became metastatic to the penis and prostate 6 years after treatment. CASE REPORT A 46-year-old man presented in 1992 with a synovial sarcoma of the lower back, which was resected at diagnosis. In 1997 he had metastatic disease to the upper lobe of the left lung and underwent thoracotomy with lobectomy. Disease recurred in the same area 4 months later and was resected. In 1998 the patient had a lesion on the penis, which was biopsied and consistent with synovial sarcoma. He received 7,000 rad to the penis and perineum. In April 2000 he had a firm nodule at the left base of the penis, which was biopsied and revealed recurrent sarcoma. The patient was referred to us for definitive treatment. Total penectomy and perineal urethrostomy were performed. Frozen sections from the proximal margin of the penectomy and the subcutaneous tissues near the urethrostomy were positive for sarcoma. After discussion the patient underwent total emasculation and cystoprostatectomy. Pathological examination was consistent with the diagnosis of monophasic type synovial sarcoma (fig. 1). Cancer was in the remaining penis, prostate and surrounding fibroadipose tissue (fig. 2). All surgical margins were negative. Convalescence was uneventful. Back pain developed 7 months postoperatively and magnetic resonance imaging revealed lesions in 5 contiguous segments of the thoracolumbar spine with circumferential compression at T11 to T12. The patient complained only of lower extremity parathesias, and the neurological examination was normal. He received a maximum dose of radiation to the area following initial tumor resection and underwent thoracolumbar decompression, fixation and instrumental fusion from T9 to L3. Convalescence was uneventful. DISCUSSION
Saturation of deuterium retention in carbon a new calibration for plasma edge probes

Abstract Depth profiles were measured for deuterium implanted in carbon at 530, 1500, and 3000 eV. Measured profiles were in good agreement with profiles calculated using the TRIM code. Comparison between profiles for high and low fluence implants show a scaling of the local deuterium concentration with incident deuterium fluence up to a saturation concentration of 0.44 ± 0.08 D/C ratio. New measurements of retention versus fluence for monoenergetic deuterium implanted in carbon for incident energies from 300 to 1500 eV are in very good agreement with the retention behavior predicted by a saturation model using the observed depth profiles and saturation concentrations. The retention is calculated for deuterium with a Maxwellian velocity distribution to provide a new calibration for the determination of the energy and flux of deuterium incident on carbon probes exposed to the edge of magnetically confined plasmas. This new calibration gives deuterium energies and fluxes significantly different from those obtained using earlier calibrations. A simple analytic representation is also presented for retention of deuterium with a Maxwellian velocity distribution which provides a systematic approach for analyzing probe data.
Time-domain terahertz spectroscopy of artificial skin

Time-domain Terahertz (THz) spectroscopy and imaging is currently evaluated as a novel tool for medical imaging and diagnostics. The application of THz-pulse imaging of human skin tissues and related cancers has been demonstrated recently in-vitro and in-vivo. With this in mind, we present a time-domain THz-transmission study of artificial skin. The skin samples consist of a monolayer of porous matrix of fibers of cross-linked bovine tendon collagen and a glycosaminoglycan (chondroitin-6-sulfate) that is manufactured with a controlled porosity and defined degradation rate. Another set of samples consists of the collagen monolayer covered with a silicone layer. We have measured the THz-transmission and determined the index of refraction and absorption of our samples between 0.1 and 3 THz for various states of hydration in distilled water and saline solutions. The transmission of the THz-radiation through the artificial skin samples is modeled by electromagnetic wave theory. Moreover, the THz-optical properties of the artificial skin layers are compared to the THz-optical properties of freshly excised human skin samples. Based on this comparison the potential use of artificial skin samples as photo-medical phantoms for human skin is discussed.
Surface Plasmon-Assisted Transmission and Emission from Subwavelength Patterned Apertures

We optimize surfaces with patterned apertures for maximized transmission and emission by coupling into and out of surface plasmon modes. We shift transmission and emission peaks in the spectrum through control of device parameters.
Prediction of Metabolic Flux Distribution from Gene Expression Data Based on the Flux Minimization Principle

Prediction of possible flux distributions in a metabolic network provides detailed phenotypic information that links metabolism to cellular physiology. To estimate metabolic steady-state fluxes, the most common approach is to solve a set of macroscopic mass balance equations subjected to stoichiometric constraints while attempting to optimize an assumed optimal objective function. This assumption is justifiable in specific cases but may be invalid when tested across different conditions, cell populations, or other organisms. With an aim to providing a more consistent and reliable prediction of flux distributions over a wide range of conditions, in this article we propose a framework that uses the flux minimization principle to predict active metabolic pathways from mRNA expression data. The proposed algorithm minimizes a weighted sum of flux magnitudes, while biomass production can be bounded to fit an ample range from very low to very high values according to the analyzed context. We have formulated the flux weights as a function of the corresponding enzyme reaction's gene expression value, enabling the creation of context-specific fluxes based on a generic metabolic network. In case studies of wild-type Saccharomyces cerevisiae, and wild-type and mutant Escherichia coli strains, our method achieved high prediction accuracy, as gauged by correlation coefficients and sums of squared error, with respect to the experimentally measured values. In contrast to other approaches, our method was able to provide quantitative predictions for both model organisms under a variety of conditions. Our approach requires no prior knowledge or assumption of a context-specific metabolic functionality and does not require trial-and-error parameter adjustments. Thus, our framework is of general applicability for modeling the transcription-dependent metabolism of bacteria and yeasts.
A Mitochondrial ATP Synthase Subunit Interacts with TOR Signaling to Modulate Protein Homeostasis and Lifespan in Drosophila

SUMMARY Diet composition is a critical determinant of lifespan, and nutrient imbalance is detrimental to health. However, how nutrients interact with genetic factors to modulate lifespan remains elusive. We investigated how diet composition influences mitochondrial ATP synthase subunit d (ATPsyn-d) in modulating lifespan in Drosophila. ATPsyn-d knockdown extended lifespan in females fed low carbohydrate-to-protein (C:P) diets but not the high C:P ratio diet. This extension was associated with increased resistance to oxidative stress; transcriptional changes in metabolism, proteostasis, and immune genes; reduced protein damage and aggregation, and reduced phosphorylation of S6K and ERK in TOR and mitogenactivated protein kinase (MAPK) signaling, respectively. ATPsyn-d knockdown did not extend lifespan in females with reduced TOR signaling induced genetically by Tsc2 overexpression or pharmacologically by rapamycin. Our data reveal a link among diet, mitochondria, and MAPK and TOR signaling in aging and stresses the importance of considering genetic background and diet composition in implementing interventions for promoting healthy aging.
OPTIMAL PORTFOLIO SELECTION STRATEGIES IN THE PRESENCE OF TRANSACTION COSTS

We consider an investor who has available a bank account (risk free asset) and a stock (risky asset). It is assumed that the interest rate for the risk free asset is zero and the stock price is modeled by a diffusion process. The wealth can be transferred between the two assets under a proportional transaction cost. Investor is allowed to obtain loans from the bank and also to short-sell the risky asset when necessary. The optimization problem addressed here is to maximize the probability of reaching a financial goal a before bankruptcy and to obtain an optimal portfolio selection policy. Our optimal policy is a combination of local-time processes and jumps. In the interesting case, it is determined by a non-linear switching curve on the state space. This work is a generalization of Weerasinghe [20], where this switching boundary is a vertical line segment.