cssi/SciSciGPT-SciSciNet huggingface dataset:
Ray tracing visualization toolkit

The Ray Tracing Visualization Toolkit (rtVTK) is a collection of programming and visualization tools supporting visual analysis of ray-based rendering algorithms. rtVTK leverages layered visualization within the spatial domain of computation, enabling investigators to explore the computational elements of any ray-based renderer. Renderers utilize a library for recording and processing ray state, and a configurable pipeline of loosely coupled components allows run-time control of the resulting visualization. rtVTK enhances tasks in development, education, and analysis by enabling users to interact with a visual representation of ray tracing computations.
Molecular characterization of two Pepino mosaic virus variants from imported tomato seed reveals high levels of sequence identity between Chilean and US isolates

Pepino mosaic virus (PepMV), a member of the genus Potexvirus, was first described in South America on pepino (Solanum muricatum A.). Only in recent years, it was reported to infect greenhouse-grown tomatoes. Genome nucleotide sequences from several European isolates showed extensive sequence identity (>99%). Recent genome nucleotide sequences from two US isolates (US1 and US2) however showed much greater sequence divergence from that of the European PepMV isolates. My interest in characterizing virus isolates from South America was due to an active commercial tomato seed production in Chile. Through genome sequence comparison and phylogenetic analyses, we may be able to understand the source of virus infection and control this devastating disease from further spreading into new tomato growing regions of the world. Complete genome nucleotide sequences from two PepMV variants (designated as Ch1 and Ch2) were determined from a virus isolate obtained from a commercial tomato seed lot produced in Chile. Using RT-PCR-based genome walking strategy, complete genome sequences from these two variants were determined. Excluding poly (A) tails, the genomes of PepMV Ch1 and Ch2 were 6414 and 6412 nucleotides (nt), respectively. Pairwise comparisons of PepMV Ch1 and Ch2 genomes with other PepMV isolates showed that the highest nucleotide sequence identity was with two US isolates, 98.7% between PepMV Ch1 and US1, and 90.7% between Ch2 and US2. Similar to PepMV US1 and US2, the two Chilean variants were the most divergent from one another (78% nt identity). These two Chilean PepMV variants also shared only 78-86% nucleotide sequence identity to that of five European isolates. The high level of nucleotide sequence identity between Chilean and US isolates suggests a common origin. Phylogenetic analyses with various gene products generated three distinct sequence clusters (or strains): US1 and Ch1 in the first group, US2 and Ch2 in the second, and the European tomato isolates in the third. Based on the host specificity, it was previously suggested that the original pepino isolate should be considered a distinct strain from that of the tomato isolates.
Personal information privacy: implications for MIS managers

Abstract Recent media attention to information privacy issues has shown that citizens are increasingly concerned about information privacy and their right to it. Governmental and other organizations have been collecting data about individuals at an increasing and, to many, alarming rate. The ability to gather so much information on individuals is largely because of advances in information technology (IT). It is important for IS managers and professionals to understand the issues surrounding personal information privacy in order to protect the rights of those from and about whom they collect data. A model is presented to provide managers guidance in dealing with privacy policy. Taking a proactive stance against privacy invasion could help stave off government intervention in passing legislation to create tighter controls over what can be done with an individual's personal data.
Barreloids in adult rat thalamus: three-dimensional architecture and relationship to somatosensory cortical barrels.

Histochemical staining for cytochrome oxidase (CO) and axonal transport of horseradish peroxidase (HRP) were used to investigate thalamocortical connections in the vibrissa-barrel system of adult rats. CO staining revealed that the medial division of the ventrobasal thalamic nucleus (VBm) consists of intensely stained rod-like configurations, containing thalamocortical projection neurons and intervening neuropil, separated by lighter-stained septa. CO-dark rods span the thickness of VBm, are arranged in a pattern of rows and arcs that resembles the distribution of vibrissae on the mystacial pad, and are similar to the cytoarchitectonic structures termed “barreloids” in the mouse thalamus. Based upon the dimensions of CO-dark structures and the numerical density of neurons in VBm we estimated that a barreloid in the rat may contain 250-300 neurons. HRP injections into lamina IV of the somatosensory cortex led to retrograde labeling of neurons within one or more barreloids. When injections were centered within the CO-dark hollows of cortical barrels about 95% of retrogradely labeled neurons were located in the barreloid that is isomorphic to the injected barrel; up to 5% of labeled neurons were located within a single adjacent barreloid. Barrel hollow injections that also included a barrel side yielded a larger proportion of labeled neurons in non-isomorphic barreloids. Interestingly, such extra-barreloid labeling was topologically consistent in that HRP-labeled neurons were distributed among barreloids that corresponded to cortical barrels nearest the injected barrel side. Injections into the septa between barrels similarly resulted in labeling within barreloids that corresponded to cortical barrels flanking the septal injection site. Following lamina IV injections the density of labeled neurons tended to be highest in the ventrolateral one-half to two-thirds of VBm. Retrograde labeling of neurons in the dorsomedial one-third to one-half of VBm was more often observed after HRP injections at the lamina V/VI border. Thus, barreloid neurons may be heterogeneous with respect to their laminar pattern of terminations within the somatosensory cortex. Some HRP injections in the cortex resulted in orthograde labeling of corticothalamic axons in the barreloids. When observed, labeled corticothalamic axons arborized principally within the barreloid isomorphic to the injected barrel column. Indeed, terminal labeling was densest in the vicinity of neurons retrogradely labeled by the same injection.
Diffusion length and grain-boundary recombination velocity measurements with the scanning electron microscope in a finite polysilicon grain

Abstract The three-dimensional boundary-value problem that defines the minority-carrier transport is solved analytically to obtain the EBIC response of a finite-sized polycrystalline grain. The collecting junction is perpendicular to two grain boundary surfaces which are in close proximity. The analysis requires incorporating an additional boundary condition for a second surface into the standard analysis for a junction perpendicular to a surface. The analytic solution uses an infinite number of images for the spherical generation volume and has been completely worked out for the case where the two surfaces have finite (not just zero or inifinite) surface recombination velocities. The resultant analytic expression for the EBIC current is a function of the grain size, the diffusion length in the bulk grain, the distance of the center of the generation volume from the grain boundary, the depth of the gneration volume, and the grain-boundary recombination velocities. Limitations of the solution are discussed and some experimental data, interpreted using the above theoretical analysis, are presented.
Analysis and differentiation of mechanism of tolerance to methadone in methadone-fed rats.

Abstract Rats fed methadone in drinking water (0.5 mg/ml) for 1 or 2 weeks developed tolerance to the analgesic effect of methadone as measured by the hot-plate method. This decreased analgesia was accompanied by an increased methadone N -demethylase activity measured in vitro and an increased methadone metabolism in vivo as judged by increases in the percentages of total 14 C as 14 C-water-soluble metabolites in the liver and urine 3 hr after administration of [ 14 C]methadone. Two-day oral methadone administration and 4-day phenobarbital pretreatment also increased methadone metabolism both in vitro and in vivo and decreased the analgesic effect of methadone but not of morphine, indicating that increased methadone metabolism contributed to the development of tolerance to methadone analgesia (dispositional tolerance). Methadone-fed rats also developed cross-tolerance to morphine-induced analgesia. Two-week feeding caused tolerance to the analgesic effects of methadone and morphine to a greater degree. However, there was no significant difference between the increases in methadone metabolism produced by 1- and 2-week feedings. These results indicate that dispositional tolerance did not account for all of the tolerance seen after chronic methadone feeding. This suggests that chronic methadone feeding also caused cellular adaptive tolerance. This suggestion is further supported by the evidence that 4-day phenobarbital pretreatment, enhanced methadone metabolism more than 2-week methadone feeding, but the decrease in methadone analgesia caused by phenobarbital pretreatment was not as great as that caused by 2-week methadone feeding. It is concluded that tolerance to methadone analgesia as a result of chronic methadone feeding arises due to both increased metabolic inactivation of methadone and cellular adaptation to the drug in the brain.
Authoritarianism and Attitudes toward Children

(1957). Authoritarianism and Attitudes toward Children. The Journal of Social Psychology: Vol. 45, No. 1, pp. 107-110.
Structural, hydrogen storage, and electrochemical properties of Laves phase-related body-centered-cubic solid solution metal hydride alloys

Abstract Structure, gaseous phase hydrogen storage, and electrochemical properties of a series of Laves phase-related BCC solid solution metal hydride alloys with BCC/C14 ratios ranging from 0.09 to 8.52 were studied. Some properties are correlated to the phase abundance and V-content in the alloy with monotonic evolutions, for example, lattice constant, phase abundance, and hydrogen storage pressure. Other properties such as gaseous phase capacities, PCT hysteresis, high-rate dischargeability, and bulk hydrogen diffusion correlate better with the C14 phase crystallite size, which are considered to be more related to the synergetic effect between main and secondary phases. In contrast with conventional metal hydride alloys used in NiMH batteries, the electrochemical discharge capacities of these alloys are not between the maximum and the reversible hydrogen storage measured in the gaseous phase. The current study's alloys have electrochemical capacities that are insensitive to composition but have much room for improvement, with high-rate dischargeabilities that are superior compared to other commercially available alloys. With further research, these alloys show potential for high-rate battery applications.
Leveraging rule-based designs for automatic power domain partitioning

Leakage power reduction through power gating requires considerable design and verification effort. We present a scheme which uses high-level design description to automatically generate a collection of fine-grain power domains and associated control signals. We also describe a method of collecting the dynamic activity characteristics of a domain, viz. total inactivity and frequency of inactive-active transitions, which are necessary to decide the domain's suitability for power gating. Our automated power-gating technique provides power savings without exacerbating the verification problem because the power domains are correct by construction. We illustrate our technique using two wireless decoder designs.
BYPASS1: How a Tiny Mutant Tells a Big Story about Root-to-shoot Signaling

Plants coordinate their development using long-distance signaling. The vascular system provides a route for long-distance movement, and specifically the xylem for root-to-shoot signaling. Root-to-shoot signals play roles communicating soil conditions, and these signals are important for agricultural water conservation. Using genetic approaches, the Arabidopsis bypass1 (bps1) mutant, which over-produces a root-derived signal, was identified. Although bps1 mutants have both root and shoot defects, the shoot can develop normally if the roots are removed, and the mutant root is sufficient to induce arrest of the wild-type shoot. BYPASS1 encodes a protein with no functionally characterized domains, and BPS1-like genes are found in plant genomes, but not the genomes of animals. Analyses of hormone pathways indicate that the mobile compound that arises in bps1 roots requires carotenoid biosynthesis, but it is neither abscisic acid nor strigolactone. The current model suggests that BPS1 is required to prevent the synthesis of a novel substance that moves from the root to the shoot, where it modifies shoot growth by interfering with auxin signaling.
Finding cancer in asymptomatic people. Estimating the benefits, costs and risks.

There are no absolute criteria for determining the effect of early detection on cancer mortality, and evidence from many sources must be examined. The best evidence is provided by randomized controlled trials that use mortality as an endpoint (RCTMs), but this type of evidence is available for only two cancers, i.e., of the breast and colon. The decision to recommend a test for a particular person must take into account the strength of the evidence that early detection reduces mortality, the expected amount of the reduction, the chance the person will ever get the cancer, and the anticipated costs and risks. This paper describes the evidence that early detection of various cancers reduces mortality, and estimates the expected reduction in mortality to be achieved by various tests. Three specific examples are discussed: breast self-examination, mammography in women younger than age 50 years, and chest x-rays for male smokers over age 40.
Sulfur-poisoning of the oxidation of H2 and CO over A (Pd+CeO2)γ-A1203 catalyst

Abstract The effect of SO 2 on the activity of a (Pd+CeO 2 )γ-A1 2 0 3 catalyst was evaluatedwith respect to the oxidation of H 2 and CO by 0 2 . The presence of SO 2 at a concent-ration of 20 ppm adversely affected the catalyst activity in varying degrees. Inthe case of H 2 oxidation, the extent of poisoning increased with the H 2 /0 2 ratioand the overall reaction was found to be of negative order (-0.5 or 1 depending on temperature) with respect to H 2 and of second order with respect to 0 2 . The H 2 oxidation was also significantly inhibited by CO. In the case of CO oxidation in the absence of H 2 , the S-poisoning was found to be relatively moderate and the overall reaction was of 1/2 order with respect to both CO and 0 2 . The S-poisoning of CO oxidation was enhanced by the presence of H 2 , especially when the oxygen present was below the stoichiometric amount.
Evaluation of the potential of Hyperion for fire danger assessment by comparison to the Airborne Visible/Infrared Imaging Spectrometer

Parameters derived from remote sensing that can be used to assess fire danger include surface reflectance, live and dead biomass, canopy water content, species composition, and fuel state. Spectral bands and wavelength locations of traditional multispectral data make assessment of fire danger in Mediterranean shrublands difficult, although fire danger parameters have been derived from Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data. We compare nearly simultaneous acquisition of Hyperion and AVIRIS to evaluate spaceborne monitoring potential of fire danger in Southern California chaparral. Field spectra were acquired to support reflectance retrieval and construct a spectral library for vegetation mapping. Reflectance spectra retrieved from Hyperion and AVIRIS had similar shape and albedo, but SNR was five times higher in AVIRIS. Fuel condition was assessed using the endmember fractions from spectral mixture analysis, with both Hyperion and AVIRIS imaging spectrometer data providing similar fractions and spatial distributions. Hyperion demonstrated good capability for separating spectral signals from bare soil and dry plant litter. Canopy water content was compared using the 980- and 1200-nm liquid water bands, the water index, and the normalized difference water index. Results showed that Hyperion is capable of retrieving canopy water at 1200 nm, but demonstrates poor performance at 980 nm. Sensor noise and instrumental artifacts account for poor performance in this spectral region. Overall, full-spectrum measures outperformed band ratios because of a lower sensitivity to sensor noise in individual bands. Species and community mapping showed similar patterns with better accuracy for AVIRIS relative to Hyperion, but with both instruments achieving only 79% and 50% overall accuracy, respectively.
From polynomial matrices to markov parameters and back: Theory and numerical algorithms

Abstract We consider polynomial matrix representations of MIMO linear systems and their connection to Markov parameters. Specifically, we consider polynomial matrix models in an arbitrary operator ρ, and develop theory and numerical algorithms for transforming polynomial matrix models into Markov parameter models, and vice versa. We also provide numerical examples to illustrate the proposed algorithms.
The esg locus of Myxococcus xanthus encodes the E1α and E1β subunits of a branched‐chain keto acid dehydrogenase

Summary The esg locus of Myxococcus xanthus appears to control the production of a signal that must be transmitted between cells for the completion of multicellular development DNA sequence analysis suggested that the esg locus encodes the E1 decarboxylase (composed of E1α and E1β subunits) of a branched-chain keto acid dehydrogenase (BCKAD) that is involved in branched-chain amino acid (BCAA) metabolism. The properties of an esg ::Tn5 insertion mutant supported this conclusion. These properties include: (i) the growth yield of the mutant was reduced with increasing concentrations of the BCAAs in the medium while the growth yield of wild-type cells increased, (ii) mutant extracts were deficient in BCKAD activity, and (iii) growth of the mutant in media with short branched-chain fatty acids related to the expected products of the BCKAD helped to correct the mutant defects in growth, pigmentation and development. The esg BCKAD appears to be involved in the synthesis of long branched-chain fatty acids since the mutant contained reduced levels of this class of compounds. Our results are consistent with a model in which the esg-encoded enzyme is involved in the synthesis of branched-chain fatty acids during vegetative growth, and these compounds are used later in cell-cell signalling during development.
Comparison of the extent and severity of myocardial perfusion defects measured by CT coronary angiography and SPECT myocardial perfusion imaging.

Objectives We compared electrocardiogram-gated computed tomography (CT) myocardial perfusion imaging (MPI) based on quantification of the extent and severity of perfusion abnormalities to that measured with single-photon emission computed tomography (SPECT) MPI. Background Contrast-enhanced CT-MPI has been used for the identification of myocardial ischemia. Methods We performed CT-MPI during intravenous adenosine infusion in 30 patients with perfusion abnormalities on rest/adenosine stress SPECT-MPI acquired within 60 days (18 stress-rest CT-MPI and 12 stress CT-MPI only). The extent and severity of perfusion defects on SPECT-MPI were assessed on a 5-point scale in a standard 17-segment model, and total perfusion deficit (TPD) was quantified by automated software. The extent and severity of perfusion defects on CT-MPI was visually assessed by 2 observers using the same grading scale and expressed as summed stress score and summed rest score; visually quantified TPD was given by summed stress score/(maximal score of 68) and summed rest score/68. The magnitude of perfusion abnormality on CT-MPI in regions of the myocardium was defined. Results On a per-segment basis, there was good agreement between CT-MPI and SPECT-MPI with a kappa of 0.71 (p Conclusions Stress and reversible myocardial perfusion deficit measured by CT-MPI using a visual semiquantitative approach and a visually guided software-based approach show strong similarity with SPECT-MPI, suggesting that CT-MPI–based assessment of myocardial perfusion defects may be of clinical and prognostic value.
A Model for Social Work Field Practicums in African American Churches

Abstract In this paper the authors will give an overview of the history of the African American church, discuss the reciprocal benefits of social work educational practicums in this institution for both students and the church, and give a model for practicum learning that can be met through this arrangement.
Non-aggregated hyperbranched phthalocyanines: single molecular nanostructures for efficient semi-opaque photovoltaics

A series of single molecular nanostructured hyperbranched phthalocyanines, HBMPc-COOH (M = H2, AlCl, Co, Cu, Zn), have been synthesized, characterized, and systematically studied as efficient semi-opaque sensitizers of TiO2 by using ultraviolet-visible absorption, steady-state and femtosecond time-resolved fluorescence, cyclic voltammetry, current–voltage and photoelectric measurements. The inherent steric effect within these hyperbranched structures effectively suppresses the aggregation of phthalocyanine rings on TiO2 surface, providing a facile approach for improving the photovoltaic performance of phthalocyanine-based dye sensitized solar cells (DSSCs). A power conversion efficiency of 1.15% along with a high incident photon to current conversion efficiency of 66.7% at 670 nm is achieved from HBZnPc-COOH sensitized solar cells. These results are consistent with findings from the femtosecond time-resolved fluorescence study, which reveals an ultrafast and efficient multi-phasic interfacial electron injection from both the Soret and Q bands to the conduction band of TiO2. The changing of the metal centers dramatically affects the optical, photophysical, electrochemical, and photovoltaic properties of the hyperbranched phthalocyanines. Zinc has been found to be the best metal center in the whole series for the design of hyperbranched phthalocyanine-based dyes for DSSC applications.
Active surveillance of very-low-risk prostate cancer in the setting of active treatment of benign prostatic hyperplasia with 5α-reductase inhibitors.

Objective To review the efficacy of treating benign prostatic hyperplasia and very-low-risk prostate cancer (PCa) in patients receiving active surveillance and 5α-reductase inhibitor (5-ARI; finasteride or dutasteride) treatment. Materials and Methods Eighty-two men with very-low-risk PCa (clinical stage T1c, Gleason score ≤6, 3 ) received active surveillance and were treated with a 5-ARI. Results All 82 men completed 1 year of 5-ARI therapy (n = 79) or underwent early biopsy for cause (n = 3). Restaging biopsies were performed for 76 men (22 underwent a second restaging biopsy and 1 a third restaging biopsy), 4 patients were awaiting biopsy, and 2 were lost to follow-up before the first restaging biopsy. At the first restaging biopsy, of the 76 men, 41 (54%) had no PCa, 16 (21%) continued to have very-low-risk PCa, 15 (20%) had progressed to low-risk PCa (>2 cores positive and Gleason score ≤6), and 4 (5%) had progressed to intermediate-risk PCa (Gleason score 7). Of the 76 biopsies, 20 were performed early for cause, with 11 (55%) showing PCa progression. Of the 82 patients, 22 (27%) underwent treatment of PCa. Conclusion Active surveillance of very-low-risk PCa in the setting of 5-ARI therapy for benign prostatic hyperplasia appears to be a safe therapeutic option, because most (57 of 82; 70%) patients maintained very-low-risk PCa or had negative follow-up biopsies during a 3-year follow-up period. Complementary to the Prostate Cancer Prevention Trial, our results indicate that 5-ARI therapy increases prostate-specific antigen sensitivity and can aid the clinician in appropriately targeting biopsies.
An online multimedia language assistant for people with aphasia and other language barriers

Individuals with aphasia, a language disorder, are seldom able to utilize the Internet as a source of information, because their disability makes many written words incomprehensible. A similar situation exists for individuals who read and speak a second language but do not possess a vocabulary as extensive as in their native language. Pictures have been demonstrated to help in both cases. However, few existing paper or electronic picture dictionaries provide efficient, scalable, and adaptable support for looking up unknown terms encountered when browsing the web. For my thesis research, I am designing and developing an Online Multimedia Language Assistant, which allows a reader to click on an unknown word and receive interpretations of the word in as many as five different multimedia representations. The system provides a popup dictionary, images, animations and audio, where applicable. It is also adaptable (by user) and adaptive (system).
A new concept for high-cycle-life LEO : rechargeable MnO2-hydrogen batteries

Abstract The nickel—hydrogen secondary battery system, developed in the early 1970s, has become the system of choice for geostationary earth orbit (GEO) application. However, for low earth orbit (LEO) satellites with long expected lifetimes the nickel positive limits performance. This requires derating of the cell to achieve very long cycle life. A new system, rechargeable MnO2—hydrogen, which does not require derating, is described here. For LEO applications, it promises to have longer cycle life, higher rate capability, a higher effective energy density, and much lower self-discharge behavior than those of the nickel—hydrogen system.
Detection of Photochemical Oxidation of Sulphur Dioxide by Condensation Nuclei Techniques

THE purpose of the tests reported in this communication was to prove that condensation nuclei techniques could be used in a qualitative way in the determination of the predominating reaction. Since quantitative performance depends on controlling several variables, proof that qualitative determinations were possible was needed to justify further work. Since sulphuric acid particles have been found to act readily as condensation nuclei, the manner of their formation from sulphur dioxide in the atmosphere was chosen as the subject of the investigation.
Ultra-low noise avalanche photodiodes with a "centered-well" multiplication region

We report avalanche photodiodes with a "centered-well" multiplication region that have achieved high gain, low noise, and low dark current. The multiplication region consists of an /spl sim/80 nm-thick Al/sub 0.2/Ga/sub 0.8/As layer sandwiched between two thin (10/spl sim/20 nm) layers of Al/sub 0.6/Ga/sub 0.4/As. Monte Carlo simulation shows the beneficial effect of spatial modulation of the ionization rates in this structure compared to homojunctions.
Calcium dependence of rat brain tryptophan hydroxylase.

The effects of various concentrations of ionized Ca were examined on the activity of rat brain tryptophan hydroxylase previously treated with EGTA. Within the range of ionized Ca-concentrations thought, to be physiologically important (10−8 to 10−5 M), no significant activation of the enzyme occurred, although activation was observed at higher concentrations of the metal.
A lower bound for the distribution of a partial product of latent roots

A lower bound is given for the cumulative distribution of T=θ1 θ1…θs , the product of the s largest solutions to |E-θ(E+H)|=0 wherein E .and H are Wishart variables with equal dispersion; E is centrally distributed; H has noncentrality matrix Δ and rank(Δ)<r=m−s. The application is in tests of dimensionality, that is, tests concerning the rank Δ on those occasions where large sample theory may not be pertinent.
The effects of anterior infarction complicated by bundle branch block upon the form of the QRS complex of the canine electrocardiogram

Abstract In dogs, myocardial infarcts induced by ligating the anterior descending coronary artery in its middle third do not usually modify the QRS complexes of the standard limb leads in a characteristic manner when bundle branch block is present. When such infarcts are complicated by right bundle branch block, the QRS complexes of unipolar leads from the right side of the precordium display a large, initial Q deflection, followed by an R wave which attains its summit late in the long QRS interval. The first component is due to potential variations transmitted from the epicardial surface of the infarcted region, and the second to potential variations transmitted from the epicardial surface of the free wall of the right ventricle. Leads from that part of the precordium overlying the infarct present large, broad QS deflections, often conspicuously slurred or notched. When left branch block is present, infarction of the kind in question does not give rise to characteristic changes in the QRS complexes of the precordial leads because the potential of the left ventricular cavity and, therefore, of the epicardial surface of the infarcted region is positive during the earliest part of the QRS interval. In direct leads from the epicardial surface of the infarct the QRS complex consists of an initial R deflection of variable size, followed by an S component of like or greater voltage. In the case of very large lesions, QRS complexes of this kind probably occur in leads from precordial points overlying the part of the left ventricular wall which is affected, but cannot be considered reliable evidence of infarction.
Presenilin 1 Deficiency Alters the Activity of Voltage-Gated Ca2+ Channels in Cultured Cortical Neurons

Presenilins 1 and 2 (PS1 and PS2, respectively) play a critical role in mediating γ-secretase cleavage of the amyloid precursor protein (APP). Numerous mutations in the presenilins are known to cau...
Computer Vision with Theme-Based Learning (Prince, S.J.D.; 2012) [Book review]

Wesley Snyder reviews a book, "Computer Vision, Models, Learning, and Inference," that uses a theme-based (rather than a technique-based) approach to teach the basics of computer vision.
Morphogenetic Signalling: Responses to Hedgehog

Protein kinase A activity is required for signalling by the extracellular molecule Hedgehog in developing Drosophila imaginal discs, but does the kinase actually respond to the Hedgehog signal?
An estimate of average annual temperature variations for North America, 1602 to 1961

Annual surface temperature variations, 1602 to 1961, averaged over 77 United States and southwestern Canadian stations, are reconstructed from 65 aridsite tree-ring chronologies of western North America. Annual sea-level pressure reconstructions averaged over the North Pacific sector including North America and eastern Asia are inversely related to the temperature variations. Both the instrumental and reconstructed North American temperature averages are well correlated with Northern Hemisphere average temperatures during the early 20th-century warming but the correlation diminishes after the mid-1940s. The 1918 to 1947 interval is reconstructed to have been the warmest and 1877 to 1906 the coolest. The correlations between the temperature record and other high resolution temperature series from the Northern Hemisphere are generally insignificant. However, significant correlations are noted for certain 30-yr time periods. North American temperatures appear to have been out of phase with temperatures in Europe during the late 18th and early 19th centuries. Significant variations in the 30-yr mean temperatures are noted in several of the North American series. The warming early in the 20th century is the most marked followed by warming from 1717 to 1723 and from 1850 to 1866. Significant cooling occurs from 1810 to 1821 and from 1659 to 1669.
Statistical Mechanics of Hard Ellipsoids. I. Overlap Algorithm and the Contact Function

Abstract A contact function for two arbitrary ellipsoids is derived. The numerical value of the contact function is less than 1 if they overlap, and greater than 1 if they do not. This extends previous work by Vieillard-Baron, who derived an overlap criterion for spheroids without use of a contact function. The equivalence of the two criteria has been checked by extensive numerical test with spheroids. It is shown that the use of the contact function greatly facilitates the calculation of the pressure in Monte Carlo simulations.
Dynamics of exploding plasmas in a magnetic field.

The expansion of laser-ablation plasmas in a magnetic field is studied with a new Faraday-rotation magnetic imaging probe and Fourier-analyzed optical plasma images over a wide range of ion magnetization. Plasma instabilities are observed during the plasma expansion which evolve from short to long wavelengths and significantly affect the magnetic structure.
Forces due to fluctuations in the anisotropic phase-field model of solidification

Abstract Stochastic forces due to thermodynamic fluctuations are derived for the anisotropic phase-field model of solidification. The stochastic forces turn out to be anisotropic. The derivation utilizes the general principles of irreversible thermodynamics. One of the forces is the divergence of the stochastic heat flux derived by Landau and Lifshitz (Statistical Physics, Pergamon Press, Oxford, 1958). The other force is the phase-field counterpart of the interface force introduced by Karma (Phys. Rev. E 48 (1993) 3441).
Sequential sampling to determine the minimum number of host examinations required to provide a reliable flea (Siphonaptera) index.

Sequential flea indices were computed for 2 species of fleas, Dinopsyllus lypusus and Xenopsylla bantorum , collected from Nile Grass Rats ( Arvicanthis niloticus ) live-trapped during the first 6–8 days of each of 13 consecutive months in Lake Nakuru National Park, Kenya. The average number of fleas per host was calculated after each successive host capture, beginning with the 1st examination. Most of the 26 monthly sequential indices demonstrated that after 20 hosts were examined, the flea index remained stable with additional sampling. The sequential flea index will allow workers to determine their own acceptable sample size and avoid sampling the large number of hosts required for statistical accuracy.
Decreased weight gain in BB rats before the clinical onset of insulin-dependent diabetes

Inbred specific pathogen-free diabetes-prone (DP) and diabetes-resistant (DR) BB rats were crossed to produce F1 and intercrossed to produce F2 rats. Diabetes segregates in these crosses as a recessive trait on rat chromosome 4. The weight gain of genetically diabetes-prone rats born to F1 healthy parents was studied to avoid effects of maternal diabetes. The weight gain of the F2 rats was initially not different from the F1 parents. The F2 rats later developing diabetes grew in parallel with their non-affected siblings up until the last 9 days before onset. During these 9 days they showed a decreased weight gain compared to their healthy litter-mates regardless of age. We conclude that decreased weight gain precedes the abrupt clinical onset of diabetes in BB rats and that it may be due to processes associated with the selective loss of β cells.
Production of dense vapor targets for laser-plasma interaction studies with intense ultrashort pulses

The technique of laser-induced ablation of thin films from glass slide substrates has been investigated as a candidate vapor target production method for studies of both tunneling-driven x-ray/xuv recombination lasers and relativistic propagation using intense, ultra-short laser pulses. It is shown by simultaneous two-wavelength interferometry that particle densities of order 1019/cm3 are readily achieved and that some intrinsic ionization accompanies the plume formation. Absorption measurements with both 100 picosecond and 125 femtosecond pulses are consistent with observed edge velocities near 106 cm/sec. The level of ionization drive by the intense 125 femtosecond laser pulse has been coarsely estimated. Averaged estimates from spectral blue shifting of spectra transmitted through the plume are consistently lower than those obtained from evaluation of saturation intensity thresholds based on the sequential nonresonant optical field ionization (OFI) process.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
The effect of removal of the smear layer on microleakage of Class V restorations in vitro

Abstract The effect of removal of the dentinal smear layer on microleakage of Class V restorations in vitro was evaluated using 3 restorative techniques: a composite resin with its dentin bonding agent, a composite based with glass-ionomer lining cement, and a glass-ionomer restorative cement. The agent used to remove the smear layer was a commerical 10% polyacrylic acid. Removal of the smear layer did not have any affect on microleakage of each of 3 types of restorations considered separately. The results favor removal of the smear layer only when a glass-ionomer linear is used under the composite restoration. The microleakage of the glass-ionomer restorations was greater than either the composite or composite based with glass-ionomer liner.
Synthesis and Biological Activity of Nω-Hemiphthaloyl-α,ω-diaminoalkanoic Acid Analogues of Aminopterin and 3′,5-Dichloroaminopterin

Analogues of N~-(4-amino-4-deoxypteroyl)-N~-(hemiphthaloyl)-~-ornithine (PT523) with 3',5'dichloro substitution in the p-aminobenzoyl moiety or with one less or one more CH2 group in the amino acid moiety were synthesized and tested as inhibitors of dihydrofolate reductase (DHFR) activity and cell growth. Replacement of L-ornithine in PT523 by ~-2,4-diaminobutanoic acid or L-lysine did not decrease binding to human recombinant DHFR but resulted in some loss of activity against SCC25 human and SCC VI1 murine squamous cell carcinoma and against MCF-7 human breast carcinoma in culture. PT523 was several times more potent than methotrexate (MTX), aminopterin (AMT), or trimetrexate (TMQ). 3',5'-Dichloro substitution did not decrease either DHFR binding or cytotoxicity. A new synthetic route to PT523 from 2,4-diamino-6(hydroxymethy1)pteridine and methyl N~-(4-aminobenzoyl)-Nb-phthaloyl-~-ornithinate was investigated but was not found superior to previously described methods. In comparative experiments on the ability of PT523 and MTX to competitively inhibit the influx of (6R)-5,10-dideazatetrahydrofolate (DDATHF, lometrexol), used here as a surrogate for MTX and reduced folates, the Ki of PT523 was lower than that of MTX in both wild-type CCRF-CEM human leukemic lymphoblasts and the transport- and polyglutamylation-defective subline CEM/MTX. The CCRFCEM cells were 10-fold more sensitive to PT523 than to MTX, whereas the CEM/MTX cells were 240-fold more sensitive. However, in contrast to other MTX-resistant cells where collateral sensitivity to PT523 has been seen. CEM/MTX cells still showed substantial cross resistance to PT523 which may reflect an unusual heightened ability to utilize exogenous folic acid. The good correlation observed with both cell lines between the cytotoxicity of PT523 and MTX and the ability to inhibit DDATHF influx supported the view that PT523 and MTX share, at least in part, a common protein carrier for membrane transport. N~-(4-Amino-4-deoxypteroyl)-Nb-hemiphthaloyl-~
Effect of reduced air pressure on dye penetration in standardized voids

Objective. This study determined the correlation between the degree of dye penetration in standardized voids to various reduced pressures. Study design. Standardized voids of 0.50 and 0.22 mm in diameter were created in 60 human roots ; specimens were divided into five groups. Four groups were subjected to a 2% filtered aqueous methylene blue dye solution under different conditions of atmospheric pressure for 7 days and reduced pressures of a 10 torr, a 260 torr, and a 510 torr for 30 minutes. The conditions for the fifth group were similar to the last group except that ethyl alcohol was substituted for water in the dye. Results. All positive control specimens showed complete dye penetration. The least linear dye penetration was observed in passively immersed specimens. The results were significantly different from those when reduced pressure had been used (p < 0.001). There were no significant differences among the groups with reduced pressure. No significant difference was found at any pressure level between the means of dye diffusion in the 0.50 and the 0.22 mm voids. The smallest standard deviations were observed for the most reduced air pressure of 10 torr, followed by the group of the least reduced pressure of 510 torr, with the use of the tincture dye solution. Conclusions. A 10-torr reduced pressure and an application of the tincture dye solution would provide an improved method for microleakage studies.
Changes Across Time in Spike Rate and Spike Amplitude of Auditory Nerve Fibers Stimulated by Electric Pulse Trains

We undertook a systematic evaluation of spike rates and spike amplitudes of auditory nerve fiber (ANF) responses to trains of electric current pulses. Measures were obtained from acutely deafened cats to examine time-related changes free from the effects of hair-cell and synaptic adaptation. Such data relate to adaptation that likely occurs in ANFs of cochlear-implant users. A major goal was to determine and compare rate adaptation observed at different pulse rates (primarily 250, 1000, and 5000 pulse/s) and describe them using decaying exponential models similar to those used in acoustic studies. Rate-vs.-time functions were best described by two-exponent models and produced time constants similar to (although slightly greater than) the “rapid” and “short-term” components described in acoustic studies. There was little dependence of these time constants on onset spike rate, but pulse-rate effects were noted. Spike amplitude changes followed a time course different from that of rate adaptation consistent with a process related to ANF interspike intervals. The fact that two time constants governed rate adaptation in electrically stimulated and deafened fibers suggests that future computational models of adaptation should not only include hair cell and synapse components, but also components determined by fiber membrane characteristics.
Morphological pattern restoration: optimal structuring elements

Abstract — In this paper, we derive the optimal structuring elements of morphological filters in image restora-tion. The expected pattern transformation of random sets is presented. An estimation theory framework for randomsets is subsequently proposed. This framework is based on the least mean difference (LMD) estimator. The leastmean difference (LMD) estimator is defined to minimize the cardinality of the expected pattern transformation of theset-difference of the parameter and the estimate. Several important results for the determination of the least meandifference (LMD) estimator are derived. The least mean difference (LMD) structuring elements of morphologicalfilters in image restoration are finally derived.Keywords: mathematical morphology, nonlinear filtering, pattern restoration, random set theory. I. Introduction Pattern restoration is an important problem in image processing and analysis applications. Various methods havebeen proposed for pattern restoration. Among the most important techniques is the median filter (and its repeatediterations) [1-2]. The median filter has been proven to minimize the absolute-value of the error [1]. The ubiquity ofthe median filter (and its repeated iterations) is further attributed to its superior performance in pattern restorationapplications [2]. The implementation of this technique, however, results in a high computational complexity due tothe large number of iterations required.A more recent approach to pattern restoration is based on morphological filters (i.e., increasing and idempotentoperators) [3-9]. In [10-13] morphological filters have been demonstrated to provide an approximation of medianfilters. The popularity of morpholoigcal filters in pattern restoration applications is ultimately attributed to theirperformance [14-19]. The main advantage of morphological filters is due to their idempotence (i.e., single iterationfilters) [3-9]. Fast algorithms for the implementation of morphological filters have also been proposed [20]. As aresult, a very low computational complexity is required for the implementation of morphological filters.In the theory of mathematical morphology an image is probed by a siruduring element which interacts withthe image in order to extract useful information about the geometrical structure of the image {3-9J. A fundamentalproblem in the application of mathematical morphology is the determination of the optimal structuring element. Theperformance of the morphological filters in pattern restoration is critically dependent on the choice of the structuringThis work was supported by the Office of Naval Research Award N00014-91-J-1725.
How to Solve a Cubic Equation, Part 4: The 111 Case

It should not be surprising that in solving cubic equations, sooner or later you are going to have to take the cube root of something. But it's not immediately obvious what cubic equations have to do with arc cosines. Well, in the general case of complex coefficients and roots we would need to take the cube root of a complex number
Stem cell factor, interleukin-16, and interleukin-2 receptor alpha are predictive biomarkers for delayed and slow graft function.

Introduction. Delayed graft function (DGF) and slow graft function (SGF) due to ischemic and reperfusion injury (IRI) are common complications of deceased donor kidney transplantation. We tested whether a panel of serum and urine cytokines represent early biomarkers for DGF and SGF. Methods. We collected serum and urine samples from 61 patients 48 hours posttransplantation and used a multiplex enzyme-linked immunosorbent assay (ELISA) technique to measure levels of 23 cytokines. Fourteen patients developed poor graft function (PGF), with 6 having DGF and 8 with SGF. Results. Area under receiver operation characteristics curve (AUC) demonstrated the following: serum levels of SCF (0.88) and interleukin (IL) 16 (0.74). Conclusions. This study showed that a select panel of cytokines measured early post kidney transplantation may predict poor graft function.
Can including pros and cons increase the helpfulness and persuasiveness of online reviews? The interactive effects of ratings and arguments ☆

One guideline given to online reviewers is to acknowledge a product's pros and cons. Yet, I argue that presenting two sides is not always more helpful and can even be less persuasive than presenting one side. Specifically, the effects of two- versus one-sided arguments depend on the perceived consistency between a reviewer's arguments and rating. Across a content analysis and three experiments that vary the information provided in the online review and whether the ratings are positive or negative, the results support these predictions. Furthermore, beliefs that the reviewer is able (vs. willing) to tell the truth mediated the effects.