cssi/SciSciGPT-SciSciNet huggingface dataset:
Fast algorithms for IR drop analysis in large power grid

Due to the extremely large size of power grids, IR drop analysis has become a computationally challenging problem both in terms of runtime and memory usage. Although IR drop analysis can be naturally formulated as the problem of solving a linear system, the system is too large to be solved by existing linear solvers. In this paper, we present two iterative algorithms based on node-by-node traversals and row-by-row traversals of the power grid, respectively. Our algorithms are extremely fast and guarantee convergence to the exact solutions. In fact, they can be considered as efficient implementations of the classical successive over relaxation iterative method for solving linear systems. Our methods take full advantage of the special structure of the power grid. Experimental results show that our algorithms out-perform the random-walk-based algorithm which is the best known method today. For a 16-million node problem, our row-based algorithm took 26.47 minutes while the random-walk-based algorithm took 19.6 hours. Our row-based algorithm produced an exact solution while the random walk produced a solution with maximum error of 5.7 mV.
Maternal socialization of children's postdivorce coping: development of a measurement model

Abstract Although the role of family factors affecting children's adjustment to postdivorce stressors has been investigated, research has yet to explore how children learn strategies to cope with such events. As a first step in this process, the objectives of this study were to: (a) develop a model of mothers' dispositional socialization of coping, (b) compare, through a separate confirmatory factor analysis, this model to one assessing coping socialization situationally, (c) assess the invariance of the model across age and gender, (d) determine the stability of the model over time, (e) assess the validity of the measures, and (f) assess the consistency between mothers' own coping and coping strategies they encouraged their children to use. Participants were 258 divorced mothers who maintained custody of their children and who were divorced within the past 2 years. Results for the dispositional measure indicated that a six-factor model consisting of problem-focused, positive cognitive restructuring, avoidance, distraction, seeking support, and negative actions coping suggestions provided the best fit indexes, and model factors were invariant across age and gender. The six-factor model also fit the situational measure well, and model factor loadings were invariant across age and gender, although several factor intercorrelations differed by age or gender. The six-factor model was found to be stable for the dispositional measure when assessed through confirmatory factor analyses 5 months later. Assessments of validity indicated that the coping socialization factors were related to mothers' reports of their children's coping cross-sectionally and longitudinally, and to mothers' retrospective reports of coping socialization in actual postdivorce stressful events. Finally, there was convergence between mothers' reports of their own coping efforts with those they encouraged in their children.
Undocumented residents in the United States in 1990: issues of uncertainty in quantification.

Censuses and national surveys are monitoring net immigration to the United States as the twentieth century closes with high immigration reminiscent of the early decades. These demographic studies inferred the legal-undocumented composition for census and national survey estimates for the foreign-born population. For both net immigration and that portion attributable as net legal immigration, an increasing trend is evident since 1970. Uncertainties are abundant about the measurement of net undocumented migration and change over the past two decades. This analysis presents possible upper and lower boundaries on components for estimating legal migration in 1980-1989 and on the foreign-born population in 1990. Positing ranges for net undocumented immigration ; between 2 million and 4 million undocumented residents may have been counted in the 1990 census. The total number of undocumented residents may have been as high as 6 million. To more narrowly specify these ranges, greater exercise of judgment would be necessary but not sufficient
A mass transfer model for a twin-screw extruder

A mass transfer model was developed to represent the desorption of a volatile species from a molten polymer in an extruder consisting of co-rotating twin screws in a figure-eight bore. The melt undergoes a series of alternating exposure and mixing processes while being transported axially through the device. The model relates the ratio of entrance to exit concentrations of the volatile species to the dimensions of the screws, the rate of their rotation, the rate of polymer flow, and the diffusion coefficient of the volatile species in the polymer. Experimental data, obtained with a halocarbon-polybutene system in a twin-screw extruder, were compared with predictions of the model. For the observed performance, the model predicts a process screw length about 14 percent below the actual screw length in the experimental extruder.
Waves generated by moving pressure disturbances in rectangular and trapezoidal channels

In this paper, the existing fully nonlinear and weakly dispersive depth-integrated wave equations are modified to include the effects of moving free surface pressure. We focus our investigation on waves generated by a moving free surface pressure distribution in rectangular and trapezoidal channels. For the rectangular channels, the numerical results from the present model are compared with those obtained by the forced KdV equations. Green- Naghdi (GN) equations and the Boundary Integral Equation (BIEM) formulation based on the potential flow theory. Through these comparisons, the limitation for each approach is indicated. The present model is then employed as a tool to study the waves generated in a trapezoidal channel. A moving boundary condition is implemented to simulate the moving shoreline. Numerical experiments are performed for different channel geometry and Froude numbers.
Subnormality and composition operators on the Bergman space

Following the work of C. Cowen and T. Kriete on the Hardy space, we prove that under a regularity condition, all composition operators with a subnormal adjoint on A2(D) have linear fractional symbols of the form. Moreover, we show that all composition operators on the Bergman space having these symbols have a subnormal adjoint, with larger range for the parameterr than found in the Hardy space case.
The He(I) photoelectron spectroscopy of heavy group IV—VI diatomics

Abstract The He(I) photoelectron spectra of the Group IV—VI diatomics GeO, GeS, GeSe, GeTe, SnS, SnSe, and SnTe are presented. The outermost valence structure of these molecules is similar to that observed in the lighter series CO, CS, etc. of this valence isoelectronic group; in each case a relatively sharp peak is assigned to ionization from the nominally non-bonding 3σ orbital and a broader band to ionization from the bonding 1π orbital. At higher binding energies the spectra exhibit several peaks where only a single peak is expected, from the (2σ) −1 hole state. This structure is assigned to correlation peaks resulting from configuration interaction among hole states of 2 Σ + (Ω = 1 2 ) symmetry. Semi-empirical CNDO—MO calculations have been performed for these molecules, and the results are used to interpret the observed trends. In addition, a simple molecular orbital model is employed to estimate the importance of spin—orbit coupling in the valence electronic structure of the heavy IV—VI ions.
THE ELECTIONS: War on terror wins

(2003). THE ELECTIONS: War on terror wins. Bulletin of the Atomic Scientists: Vol. 59, No. 1, pp. 18-19.
Location of anatomic sites in brains of experimental animals based on internal landmarks

The determination of the spatial positions, with respect to a head holder reference, of anatomic structures within the brains of experimental animals, based on measurements of coordinates of ventricular and internal cranial landmarks, is described. If “appropriate” landmark arrays are employed, the uncertainty in coordinate values for prechosen anatomic sites in cat brain, determined by the methods outlined in the paper, is reduced by a factor of the order of five compared to the deviations experienced when the Horsley-Clarke landmarks are employed. The instrumentation system developed for implementing the entire procedure, including precision x-ray contrast ventriculography, and the atlas and roentgenographic data used to obtain the desired coordinate information are illustrated.
Quantitative angioscopy: A novel method of measurement of luminal dimensions during angioscopy with the use of a “lightwire”

To determine the accuracy and reproducibility of luminal dimension measurements of a newly developed method of quantitative angioscopy. A method was developed for quantitation of luminal dimensions during angioscopy, as variation in magnification with lens-object distance and ambiguity associated with identification of corresponding points about the circumference of a given discrete cross-section render subjective estimates unreliable. A transverse ring of fiberoptically transmitted light was emitted from a guidewire or its housing at a known distance from the distal end of an angioscope and discrete cross-sections of interest were observed as the ring of light was reflected from the luminal surface. Caliper measurement of the diameter of the light ring image (< 50 mW at 488/515 nm), obtained on angioscopic video recordings of cylindrical phantom vessels of known dimensions, was performed by three observers on five occasions. The mean absolute difference between measured and known luminal diameter (n = 405 observations) was 65 μm±35 μm and the mean coefficient of variation was 4.2%, and the mean difference between measured and known areas (n = 195 observations) was 0.4 mm2, with a mean coefficient of variation of 6.5%. By use of this new lightwire method, luminal dimensions can now be measuredin vitro with a high degree of accuracy and reproducibility during angioscopy.
A Fundamental Principle Governing Populations

Proposed here is that an overriding principle of nature governs all population behavior; that a single tenet drives the many regimes observed in nature—exponential-like growth, saturated growth, population decline, population extinction, and oscillatory behavior. The signature of such an all embracing principle is a differential equation which, in a single statement, embraces the entire panoply of observations. In current orthodox theory, this diverse range of population behaviors is described by many different equations—each with its own specific justification. Here, a single equation governing all the regimes is proposed together with the principle from which it derives. The principle is: The effect on the environment of a population’s success is to alter that environment in a way that opposes the success. Experiments are suggested which could validate or refute the theory. Predictions are made about population behaviors.
Effect of L-DOPA analogues in Sidman avoidance performance in mice.

Abstract Mice were trained to avoid foot shock by turning a drum mounted in the wall of a behavioral chamber. L-DOPA (178 to 320 mg/kg i.p.) and D-DOPA (320 to 1000 mg/kg, i.p.) but not L-3-0-methyl-DOPA (178 to 560 mg/kg, i.p.) significantly reduced the number of responses made by the animals. Pretreatment with Ro. 4-4602 (50 mg/kg, i.p.), a peripheral DOPA-decarboxylase inhibitor, enhanced the depressant effect of L-DOPA but not that of D-DOPA. Inhibition of central DOPA-decarboxylase (Ro. 4-4602, 500 mg/kg, i.p.) partially reduced the depressant effect of L-DOPA but not that of D-DOPA These results suggest that only part of the depressant action of L-DOPA is due to its central decarboxylation.
Heat pulse propagation studies in TFTR

The time-scales for sawtooth repetition and heat pulse propagation are much longer (tens of milliseconds) in the large tokamak TFTR than in previous, smaller tokamaks. This extended time-scale, coupled with more detailed diagnostics, has led us to revisit the analysis of heat pulse propagation as a method to determine the electron heat diffusivity χe in the plasma. A combination of analytic and computer solutions of the electron heat diffusion equation is used to clarify previous work and to develop new methods for determining χe. Direct comparison of the predicted heat pulses with soft-X-ray and ECE data indicates that the space-time evolution is diffusive. However, the χe determined from heat pulse propagation usually exceeds that determined from background plasma power balance considerations by a factor ranging from two to ten. Some hypotheses for resolving this discrepancy are discussed.
FTD and ALS: genetic ties that bind.

Curiously, amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), seemingly disparate neurodegenerative disorders, can be inherited together. Two groups (DeJesus-Hernandez et al. and Renton et al.) show that the long sought after ALS/FTD mutation on chromosomal region 9p is a hexanucleotide expansion in C90RF72. These studies, plus a study on X-linked ALS/FTD, provide molecular starting points for identifying pathways that link ALS and FTD pathogenesis.
Innovative NARX recurrent neural network model for ultra-thin shape memory alloy wire

The Nonlinear Autoregressive model with Exogenous inputs (NARX) has been utilized in many dynamic systems with complicated nonlinearities. Since NARX models can employ past values of time series as inputs, it is possible to estimate the property of hysteresis to Shape Memory Alloys (SMAs). The innovation of this paper lies in the development of a creative Jordan-plus-Elman NARX recurrent neural network (Jordan-Elman network) model as well as its training procedure. In this paper, the proposed model is applied to an ultra-thin SMA wire with a diameter of 0.001in., which can be actuated/heated by an electric current. Experimental results demonstrate that the Jordan-Elman network dramatically improves the modeling error (mean squared error) in comparison with a Jordan NARX neural network. In addition, with good generalization results, the proposed model successfully identifies and estimates the hysteretic behavior of the ultra-thin SMA wire including major loops and minor loops at various frequencies.
A geographical analysis of multiethnic households in the United States.

Using the household-level data provided by the 5% PUMS [Public Use Microdata Sample] data from the 1990 Census this paper reports the pattern of ethnic mixing at the household level in the U.S. and also describes the geographical patterns of different types of multiethnic households at both the state level and the PUMA [Public Use Microdata Area] level. Several of the largest metropolitan areas are also examined in greater detail. The strong dominance of whites in the process of ethnic mixing is clear as is the expected dominance of blacks in southeastern U.S. and the dominance of Hispanics in the southwest at the state level. The PUMA-level analysis reveals local clusters of ethnic mixing that are not apparent at the state-level analysis. (EXCERPT)
Mouse-strain differences in response to radiation.

Summary1. The acute radiation mortality of mice exposed to x-rays shows that there are radiosensitive regions in the mouse head. 2. The L.D.-50% at 12 days for acute mortality due to whole-body exposure to x-rays is essentially the same for 4 mouse strains and is about 528 r. 3. The sensitivity of the head region varies with mouse strain. In the most sensitive strain, the dba, the M.L.D. for head exposure is the same as for whole-body exposure. Up to more than a 4-fold decrease in head sensitivity in the strains is found in the following order: dba, Marsh, C57 black, and C3H mice.
Pulse combustor modeling demonstration of the importance of characteristic times

A numerical model has been developed to study the sensitivity of a pulse combustor's performance to changes in the relative timing between several of the dominant physical processes. The model is used to demonstrate the importance of the characteristic times associated with acoustics, fluid mixing, and chemical kinetics, which have been identified from both theoretical and experimental evidence. The combination of submodels for acoustics, injection, and combustion produces a pulse combustor model that is dynamic in that it fully couples the injection and mixing processes to the acoustic waves. Comparisons of simulations with experimental results show good agreement, verifying the model over a wide range of operating conditions. Because the model provides more control of the dominant processes than can be obtained in experiments, the parametric study establishes the cause-effect relation between the characteristic times and the resulting combustor performance.
The role of functional assessment in evaluating urinary incontinence

Particularly for older people, ability to function can play an important role in generating and maintaining continence. Assessment of function is essential to proper clinical evaluation and treatment of urinary incontinence. Physical, mental, environmental, and social factors should be evaluated, including mobility, balance, musculoskeletal strength and flexibility, fine motor coordination, vision, body awareness, ability to understand and follow simple instructions, motivation, access to toilet, adequacy of physical supports, availability of a caregiver, caregiver-patient dynamics, and the effect of incontinence on social interactions. Assessment strategies should involve careful first-hand observations, use of clinically appropriate assessment instruments, and, where indicated, use of a geriatric assessment team. A functional profile is useful in tailoring treatment strategies to the needs and strengths of individual patients, as well as in monitoring progress. The development of treatment plans is often best carried out in the setting of a health-care team conference.
Critical Values for Nonparametric Multiple Comparisons

Sumnmy.--Critical values for testing the significance of many-one contrasts, all-pairs contrasts, and two types of complex contrasts are presented in a single table. The table can be used in connection with four nonparametric analogs of analysis of variance, representing the one-way and two-way cases for dichotomous and ranked data: the 2 x K chi-square test, the KruskalWallis test, the Cochran Q test, and the Friedman test. Just as analysis of variance has its nonpararnetric analogs, so do the various tests that have been suggested for performing multiple comparisons (Marascuilo & McSweeney, 1977). And just as ,a number of multiple comparison tests can be cast in a common form, but with different critical values (Games, 1971), so can their nonparametric analogs. The purpose of the present note was to provide critical values for four of these analogs in a single table, thereby facilitating their use. The table can be used in connection with four nonparametric analogs of analysis of variance:
Distribution-free test in Tobit mean regression model

This paper discusses the problem of fitting a parametric model in Tobit mean regression models. The proposed test is based on the supremum of the Khamaladze-type transformation of a partial sum process of calibrated residuals. The asymptotic null distribution of this transformed process is shown to be the same as that of a time-transformed standard Brownian motion. Consistency of this sequence of tests against some fixed alternatives and asymptotic power under some local nonparametric alternatives are also discussed. Simulation studies are conducted to assess the finite sample performance of the proposed test. The power comparison with some existing tests shows some superiority of the proposed test at the chosen alternatives.
Collimator-produced energy degradation of megavoltage x rays.

Monte Carlo computer calculations have been made to assess the effects of small collimators (i.e., output field sizes ≤1 cm) on megavoltage x-ray beams. Such collimators are often used in experiments to measure beam energy, half value layers, and other beam parameters. Our calculations demonstrate, however, that such procedures can introduce significant changes in these same parameters. Under certain conditions, more than 40% of the transmitted photons exiting the collimator do so with degraded energy. Optimum collimator design, however, can greatly reduce these effects. In particular, it is shown that the thickness of material required to effect a good collimator is not only dependent upon the photon energy, but also upon the size of the collimator hole.
Benzodiazepine receptor binding of triazolobenzodiazepines in vivo: increased receptor number with low-dose alprazolam.

Triazolobenzodiazepines are in clinical use as hypnotics and anxiolytics. We analyzed in vivo receptor binding and brain concentrations of alprazolam, triazolam, and estazolam. Drug concentrations measured in the cerebral cortex 1 h after administration were directly proportional to dose for all three compounds. In vivo receptor binding, as defined by the specific uptake of [3H]Ro15-1788, decreased with increasing doses of estazolam and triazolam, a finding indicating dose-related increases in receptor occupancy due to these compounds. Triazolam was substantially more potent, with an IC50 value of 16 ng/g, compared with 117 ng/g for estazolam. At higher doses of alprazolam (greater than 0.2 mg/kg), receptor binding by [3H]Ro15-1788, likewise decreased with increasing dose of the former drug. However, at lower doses of alprazolam (0.02-0.05 mg/kg), which resulted in cortex concentrations of 2-7 ng/g, receptor binding was increased above control values in cortex, hypothalamus, and hippocampus but not in several other brain regions. Binding returned to control values at doses of greater than or equal to 0.01 mg/kg. Similar results were obtained in time course studies. At 8 and 10 h after a dose of 1 mg/kg i.p., corresponding to cortex concentrations of 2.7-7 ng/g, receptor binding was increased compared with controls. Similarly, at 1, 2, and 3 h after a single dose of 0.05 mg/kg, corresponding to cortex concentrations of 3.7-5.8 ng/g, receptor binding was also increased. The apparent affinity of benzodiazepine receptors for clonazepam in mice receiving alprazolam (0.05 mg/kg) was unchanged from that in untreated control mice, an observation suggesting that low doses of alprazolam increased receptor number.(ABSTRACT TRUNCATED AT 250 WORDS)
Life history notes on the sawfly Haplostegus nigricrus Conde (Hymenoptera: Pergidae) on Psidium guajava (Myrtaceae) in Minas Gerais State, Brazil.

Abstract The life history of Haplostegus nigricrus Conde (Hymenoptera: Pergidae), a leaf-feeding sawfly of Psidium guajava L. (Myrtaceae), was studied in Vicosa, Minas Gerais State, Brazil. The life history and morphology are compared with those of Haplostegus epimelas Konow (Hymenoptera: Pergidae), another species that feeds on guava leaves. Haplostegus nigricrus females oviposit in the midrib of guava, and larvae feed on the leaves. Late-instar larvae drop to the ground and construct a cell for pupation. Cocoons are made individually with soil particles and other substrate. Three occurrence peaks of female adults were observed for H. nigricrus and two for H. epimelas. No males of H. nigricrus were found. The importance of this study to the knowledge of South American Pergidae is discussed.
Age-Related Increase in Food Spilling by Laboratory Mice May Lead to Significant Overestimation of Actual Food Consumption: Implications for Studies on Dietary Restriction, Metabolism, and Dose Calculations

It is widely accepted that food consumption in humans declines with advanced age; however, data from mice remain controversial. Based on our previous observation that mice spill a considerable amount of food while eating, we hypothesized that increased food spillage in old mice masks actual food intake. To investigate whether mice exhibit age-associated declines in food consumption, we evaluated the actual food consumption of C57BL/6 mice at various ages by measuring both the amount of food in the food receptacle and the amount dropped to the cage bottom during feeding. We found that old mice dropped significantly more food (36% ± 8%) than young mice (18% ± 5%), which led to overestimations of food consumption, particularly in old mice. Although actual food consumption decreased in very old mice, food intake per body weight did not significantly change. These findings suggest that caution should be taken to accurately quantify food consumption by aged animals.
Decline in platelet count in patients treated by percutaneous coronary intervention: definition, incidence, prognostic importance, and predictive factors.

Aims We investigated the incidence, predictors, and prognostic impact of a decline in platelet count (DPC) in patients treated by percutaneous coronary intervention (PCI). Methods and results A total of 10 146 consecutive patients treated by PCI from 2003 to 2006 were included. According to the magnitude of the DPC, the population was divided into four groups: no DPC (<10%), minor DPC (10–24%), moderate DPC (25–49%), and severe DPC (≥50%). The primary haemorrhagic endpoint was a composite of post-procedure surgical repair major bleeding. The primary ischaemic endpoint was 30-day all-cause mortality–non-fatal myocardial infarction. Among the total population, 36% had a DPC <10%, 47.7% had a DPC of 10–24%, 14% had a DPC of 25–49%, and 2.3% had a DPC ≥50%. On multivariate analysis, moderate and severe DPC were independent predictive factors of the ischaemic outcome. Two procedural practices were identified that, if modified, might reduce the incidence of acquired thrombocytopaenia. Both the intraprocedural use of heparin (as opposed to bivalirudin) and of low molecular weight contrast material were independently associated with severe acquired thrombocytopaenia. Conclusion Moderate and severe DPC are independent predictors of adverse bleeding and ischaemic outcomes in PCI. Adoption of intraprocedural anticoagulant other than heparin and avoidance of a low molecular weight contrast agent could potentially decrease the occurrence of severe acquired thrombocytopaenia.
Competition driven by retinal waves promotes morphological and functional synaptic development of neurons in the superior colliculus

Prior to eye opening, waves of spontaneous activity sweep across the developing retina. These “retinal waves,” together with genetically encoded molecular mechanisms, mediate the formation of visual maps in the brain. However, the specific role of wave activity in synapse development in retino-recipient brain regions is unclear. Here we compare the functional development of synapses and the morphological development of neurons in the superior colliculus (SC) of wild-type (WT) and transgenic (β2-TG) mice in which retinal wave propagation is spatially truncated (Xu HP, Furman M, Mineur YS, Chen H, King SL, Zenisek D, Zhou ZJ, Butts DA, Tian N, Picciotto MR, Crair MC. Neuron 70: 1115–1127, 2011). We use two recently developed brain slice preparations to examine neurons and synapses in the binocular vs. mainly monocular SC. We find that retinocollicular synaptic strength is reduced whereas the number of retinal inputs is increased in the binocular SC of β2-TG mice compared with WT mice. In contrast, in the mainly monocular SC the number of retinal inputs is normal in β2-TG mice, but, transiently, synapses are abnormally strong, possibly because of enhanced activity-dependent competition between local, “small” retinal wave domains. These findings demonstrate that retinal wave size plays an instructive role in the synaptic and morphological development of SC neurons, possibly through a competitive process among retinofugal axons.
Vitamin e supplements: Good in theory, but is the theory good?

In this issue, Miller and colleagues provide good evidence that people should avoid high-dosage vitamin E supplementation. Taking high-dosage vitamin E in later adult life has no favorable health e...
Service learning experience: design of devices to aid children with disabilities

Service learning is a form of experiential learning in which community service provides a means of understanding academic course material and meeting clear cognitive objectives. It is "a credit-bearing, educational, experience in which students participate in an organized service activity that meets identified community needs and reflect on the service activity in such a way as to gain further understanding of course content, a broader appreciation of the discipline, and an enhanced sense of civic responsibility. By nature, service-learning programs are equally beneficial to the student as well as to the community, which differentiates it from other forms of experiential learning such as internship.
The United States Department of Energy funded program: Summer schools in nuclear and radio-chemistry

Following several national surveys that clearly indicated both a paucity of universities offering nuclear chemistry courses, and a severe shortage of personnel trained and educated in nuclear sciences, the US Department of Energy (DOE) agreed to fund a special summer program. This program would take 12 undergraduates on a competitive scholarship basis from across the nation, and provide them with an intensive 6 week course in the fundamentals of nuclear science. The first such course was taught in the summer of 1984 at San Jose State University in California, and has met each summer since that time. In this course, the students cover material equivalent to approximately 2 semester units of health physics and radiological safety, 3 semester units of lecture material on nuclear chemistry, radiochemistry, uses of radionuclides, and nuclear instrumentation, and 3 semester units of laboratory work in radiochemistry, radiation chemistry, and associated topics in nuclear science. A second course was opened in 1989, with the same curriculum and intent, and sited at the Brookhaven National Laboratory on Long Island, New York. With regard to intent, both courses are very successful, with a majority of persons going on to complete graduate degrees in some aspect of nuclear science (nuclear chemistry, nuclear physics, health physics, nuclear medicine PhD programs, and synthesis with radio-nuclides or programs such as nuclear pharmacy or pharmacology) or nuclear medicine and oncology via MD programs.
Three-dimensional biomechanical model of benign paroxysmal positional vertigo

Benign Paroxysmal Positional Vertigo (BPPV) is a common disorder of the vestibular labyrinth of the inner ear. The clinical results point toward the possibility of loose basophilic particles (otoconia) free within the labyrinth resulting in the pathology of the condition. When there is a change in head position relative to gravity, the gravito-inertial forces acting on the debris result in the displacement of the fluid (endolymph) within the labyrinth and hence, an excitatory or inhibitory neural response. This is perceived as a false sense of angular head rotation and leads to inappropriate eye movements, dizziness and severe vertigo. The present study describes biomechanical modeling of the condition of BPPV. The particle(s) were modeled as spheres free to move in the membranous labyrinth lumen (canalithiasis) and/or adhered to the cupula (cupulolithiasis). For this, differential equations describing the gravito-inertial forces acting on particle(s) under the two conditions, and the viscous interactions with the endolymph were coupled together and solved within 3D labyrinthine geometry. Results are relevant to the origin, diagnosis and treatment of Benign Paroxysmal Positional Vertigo (BPPV).
Compositional Effects of Sea-Level Rise in a Patchy Landscape: The Dynamics of Tree Islands in the Southeastern Coastal Everglades

The landscape structure of emergent wetlands in undeveloped portions of the southeastern coastal Everglades is comprised of two distinct components: scattered forest fragments, or tree islands, surrounded by a low matrix of marsh or shrub-dominated vegetation. Changes in the ma- trix, including the inland transgression of salt-tolerant man- groves and the recession of sawgrass marshes, have been attributed to the combination of sea level rise and reductions in fresh water supply. In this study we examined concurrent changes in the composition of the region's tree islands over a period of almost three decades. No trend in species com- position toward more salt-tolerant trees was observed any- where, but species characteristic of freshwater swamps increased in forests in which fresh water supply was aug- mented. Tree islands in the coastal Everglades appear to be buffered from some of the short term effects of salt water intrusion, due to their ability to build soils above the surface of the surrounding wetlands, thus maintaining mesophytic conditions. However, the apparent resistance of tree islands to changes associated with sea level rise is likely to be a temporary stage, as continued salt water intrusion will even- tually overwhelm the forests' capacity to maintain fresh water in the rooting zone.
Implementation of the ECEPP algorithm, the Monte Carlo minimization method, and the electrostatically driven Monte Carlo method on the Kendall square research KSR1 computer

In this article the adaptation of the Empirical Conformational Energy Program for Peptides (ECEPP/3) and two conformational search methods [viz., the Monte Carlo minimization (MCM) method and the electrostatically driven Monte Carlo (EDMC) method] to the Kendall Square Research KSR1 computer is described. The MCM and EDMC methods were developed to surmount the multiple-minima problem in protein folding. Parallelization of these codes led to substantial speedups (expressed as the ratio between the mean time per energy evaluation in one processor and the mean time per energy evaluation in a set of processors) over the serial versions of these codes. A comparison of the performance of these algorithms on the KSR1 and on the IBM ES9000 computers is presented. © 1995 by John Wiley & Sons, Inc.
Data redundancy and reduced-scan reconstruction in reflectivity tomography

In reflectivity tomography, conventional reconstruction approaches require that measurements be acquired at view angles that span a full angular range of 2/spl pi/. It is often, however, advantageous to reduce the angular range over which measurements are acquired, in order, for example, to minimize artifacts due to movements of the imaged object. Moreover, in certain situations, it may not be experimentally possible to collect data over a 2/spl pi/ angular range. We investigate the problem of reconstructing images from reduced-scan data in reflectivity tomography. By exploiting symmetries in the data function of reflectivity tomography, we demonstrate heuristically that an image function can be uniquely specified by reduced-scan data that correspond to measurements taken over an angular interval (possibly disjoint) that spans at least /spl pi/ radians. We also identify sufficient conditions that permit for a stable reconstruction of image boundaries from reduced-scan data. Numerical results in computer-simulation studies indicate that images can be reconstructed accurately from reduced-scan data.
Variability of low‐energy ion flux profiles on interplanetary shock fronts

[1] Time-intensity profiles of 20–126 keV ions across interplanetary shocks are studied using data from ACE and Wind to determine the dependence of the profiles on spacecraft separation. Each pair of time-intensity profiles is examined to determine whether or not the same features (flat, classic energetic storm particle (ESP) rise, spikes, step functions, or complex patterns) are seen at both spacecraft. The persistence of particle profile patterns has a scale length in the plane of the shock of ∼2.9 Mkm, but the scale length along the shock normal direction is not well determined.
Multinet switch: multistage ATM switch architecture with partially shared buffers

An asynchronous transfer mode (ATM) switch architecture, the multinet switch, is presented. It is a self-routing multistage switch with internal buffers capable of achieving 100% throughput. Although it provides incoming ATM cells with multiple paths, the cell sequence is maintained throughout the switch fabric, thus eliminating the out-of-order cell sequence problem. Cells contending for the same output addresses are buffered internally according to a partial buffer sharing discipline. In a partial buffer sharing scheme, buffers are partially to accommodate bursty traffic and to limit the performance degradation that may happen in a completely shared system where a small number of calls ties up the entire buffer space unfairly. Although the hardware complexity is similar to that of the input queueing switches, the multinet switch has throughput and delay performance similar to that of output queueing switches without the hardware complexity. A simple extension of the multinet switch to handle multiple priority traffic and multicast traffic is proposed. >
Fraud and negligence in physical therapy practice: a case example

Evolving social mores and fiduciary restrictions of healthcare delivery have presented practitioners with opportunities to reflect when considering the ethical standards of practice. Using a case e...
Mixed-Lineage Kinases: A Target for the Prevention of Neurodegeneration

The activation of the c-Jun N-terminal kinase (JNK) pathway is critical for naturally occurring neuronal cell death during development and may be important for the pathological neuronal cell death of neurodegenerative diseases. The small molecule inhibitor of the mixed-lineage kinase (MLK) family of kinases, CEP-1347, inhibits the activation of the JNK pathway and, consequently, the cell death in many cell culture and animal models of neuronal death. CEP-1347 has the ability not only to inhibit cell death but also to maintain the trophic status of neurons in culture. The possible importance of the JNK pathway in neurodegenerative diseases such as Alzheimer's and Parkinson's diseases provides a rationale for the use of CEP-1347 for the treatment of these diseases. CEP-1347 has the potential of not only retarding disease progression but also reversing the severity of symptoms by improving the function of surviving neurons.
Comparison of Canal Transportation and Centering Ability of Twisted Files, Pathfile-ProTaper System, and Stainless Steel Hand K-Files by Using Computed Tomography

Abstract Introduction The purpose of this study was to compare canal transportation and centering ability of 2 rotary nickel-titanium (NiTi) systems (Twisted Files [TF] and Pathfile-ProTaper [PP]) with conventional stainless steel K-files. Methods Ninety root canals with severe curvature and short radius were selected. Canals were divided randomly into 3 groups of 30 each. After preparation with TF, PP, and stainless steel files, the amount of transportation that occurred was assessed by using computed tomography. Three sections from apical, mid-root, and coronal levels of the canal were recorded. Amount of transportation and centering ability were assessed. The 3 groups were statistically compared with analysis of variance and Tukey honestly significant difference test. Results Less transportation and better centering ability occurred with TF rotary instruments ( P P Conclusions The TF system was found to be the best for all variables measured in this study.
Growth Simulation of Facial/Head Model from Childhood to Adulthood

AbstractThis paper presents a method to simulate the growth of the facial/head model of a person from childhood to adulthood. The method works by generating continuous data of standard landmarks using auto-regressive moving average based on anthropometry of the head/face. The standard landmarks are assigned to the particular head and face, and vertices of the growing head/facial model are calculated by projecting the vertices to the one dimensional subspace that contains measurements of the landmarks. The vertices of the predicted model are constrained to keep the features of the head/face distinct by grouping vertices into clusters and maintaining proportional change of each cluster in different age periods. This new technology has applications in security, ID search (for missing children), health care (such as, evaluation of dysmorphic children) and forensic sketch artistry.
Increased Synthesis of Norepinephrine in the Rat Heart on Electrical Stimulation of the Stellate Ganglia

Electrical stimulation of the stellate ganglia results in increased formation of radioactive norepinephrine (NE) in the rat heart from L-tyrosine-14C but not from L-dopa-3H. These findings represent additional evidence that the activity of tyrosine hydroxylase, the rate-limiting step in NE synthesis, is increased by sympathetic nerve activity.
Choosing Your Battles: American Civil–Military Relations and the Use of Force

Choosing Your Battles: American Civil–Military Relations and the Use of Force. By Peter D. Feaver and Christopher Gelpi. Princeton: Princeton University Press, 2004. 236p. $37.50. The book addresses two practical and timely research concerns: the existence and significance of differences between civilian and military opinions on the commitment and nature of military force. Quantitative (mostly survey data from the Triangle Institute for Security Studies) and qualitative (case studies) data are used to systematically measure opinions about military operations among the civilian and military elites and the public, and to correlate these with national security decisions from 1819 to 1992. The authors anticipate most questions that could be raised about their methods and identify caveats and research questions yet to be addressed. Choosing Your Battles makes both scholarly contributions and intuitive sense.
The tip of the Dictyostelium discoideum pseudoplasmodium as an organizer.

We have extended Raper9s original work on the organizing ability of the tip of the Dictyostelium discoideum slug. Our new results are that tips from all multicellular (pseudoplasmodial) stages act as organizers; that the structure organized by a tip depends on the developmental stage of the cells responding to the tip9s signal; that tips from all stages release a qualitatively similar signal which is continuous, most probably a gradient of c-AMP; and that the signal from fruiting-body tips appears stronger than that from conus tips. We discuss these results with reference to the control of morphogenetic movement and patterned differentiation and point out that the D. discoideum tip is analagous to a classical organizer, whose signal is interpreted according to the state of determination of cells in its field of influence.
Innovations and Growth

In the modern technology-intensive industries of today investments in R&D and knowledge capital have played a crucial role as engines of growth. The evolution of industry has been profoundly affected by innovations in product design, process of production and software development, which have helped some firms to enhance their core cornpetence and managerial efficiency. This has also intensified the pressure of competition, which has been called a state of hypercompetition by the experts in industrial organization theory and management science.
Digital-analog hybrid SCM for fine-granularity circuit-switched optical networks

Circuit-based optical networks have the potential to provide end-to-end dedicated channels with flexible data rates between edge node pairs. However, the data-rate granularity of spectral-slicing in the optical domain based on wavelength-selective switch (WSS) is limited by the optical filter frequency selectivity. Digital subcarrier multiplexing (DSCM) in the electrical domain is able to provide much finer data rate granularity and flexibility. A downside of DSCM is its increasingly higher speed of digital electronics required to accommodate traffic carried by a wavelength. In this paper we demonstrate a digital-analog hybrid subcarrier multiplexing (SCM) technique that can reduce the speed requirement of digital electronics such as ADC and DAC, while providing wideband capability, high spectral efficiency, controllable data-rate granularity and operational flexibility. Hybrid SCM is a modular approach in which multiple digitally generated subcarriers are aggregated through RF oscillators and IQ mixers for frequency up- and down-conversions. While digital electronic processing provides high level flexibility for software controllable and spectrally efficient modulation, mature RF multiplexing and demultiplexing can inexpensively fill up the relatively wide bandwidth on a wavelength. Thanks to the rapid development of wireless systems, high quality RF oscillators and mixers are readily available with low power consumption and low cost. This paper presents experimental results which demonstrate feasibility and application perspectives of a hybrid SCM system.
Fire-climate history and landscape patterns of high burn severity areas on the California southern and central coast

There is mounting evidence that fire size and severity have been growing on the central and southern California coastal landscape over the past several decades. Landsat satellite data was analyzed for the 20 largest fires on the Central California coast since 1984 to determine the relationships between climate/weather conditions at the time of ignition and the size of high burn severity (HBS) areas. The study also examined the relationship between area burned and landscape patterns of HBS coverage, including patch size, edge complexity, perimeter-to-area ratio, and aggregation metrics. Results showed that climate conditions at the time of ignitions have been significant controllers of the total area of HBS and the complexity of HBS patches on the fire landscape. As maximum air temperatures for the month of ignition approached 40o C, the percentage of HBS to total area burned frequently exceeded 20%. The percentage of HBS to total area burned also exceed 20% when the precipitation total recorded during the previous 12 months was less than 25% of the annual average precipitation. Landscape analysis results showed that, as the total area burned in fires on the Central California coast grows, the edge lengths and areas of HBS patches also grows at a rapid rate. At the same time, the perimeter-to-area ratio of HBS patches decreases gradually and the HBS patches become more aggregated as total burned area grows.
Vocational Rehabilitation Service Patterns: An Application of Social Network Analysis to Examine Employment Outcomes of Transition-Age Individuals With Autism:

Young adults with autism spectrum disorder (ASD) face poor employment outcomes following transition from school to adult life. Social network analysis is a useful approach for examining service pat...