cssi/SciSciGPT-SciSciNet huggingface dataset:
On some properties of contracting matrices

Abstract The concepts of paracontracting, pseudocontracting and nonexpanding operators have been shown to be useful in proving convergence of asynchronous or parallel iteration algorithms. The purpose of this paper is to give characterizations of these operators when they are linear and finite-dimensional. First we show that pseudocontractivity of stochastic matrices with respect to ‖ · ‖ ∞ is equivalent to the scrambling property, a concept first introduced in the study of inhomogeneous Markov chains. This unifies results obtained independently using different approaches. Secondly, we generalize the concept of pseudocontractivity to set-contractivity which is a useful generalization with respect to the Euclidean norm. In particular, we demonstrate non-Hermitian matrices that are set-contractive for ‖ · ‖ 2 , but not pseudocontractive for ‖ · ‖ 2 or ‖ · ‖ ∞ . For constant row sum matrices we characterize set-contractivity using matrix norms and matrix graphs. Furthermore, we prove convergence results in compositions of set-contractive operators and illustrate the differences between set-contractivity in different norms. Finally, we give an application to the global synchronization in coupled map lattices.
Stresses induced in an infinite medium by the coupled diffusion of heat and moisture from a spherical hole

Abstract The diffusion of heat and moisture are interdependent processes. The mutual dependence is described by coupled equations which are solved in this paper for an infinite body with a spherical hole. The temperature and moisture concentration are initially uniform throughout the body when the values on the surface of the hole are suddenly changed to new values and held constant thereafter. The resulting nonuniform temperature and moisture distribution is time dependent and approaches a steady state, nonuniform distribution as time increases. The hygrothermal strains therefore produce a stress field which is time dependent and approaches a self-equilibrating steady state of stress. The dynamic effects of wave motion are neglected in a quasistatic solution of the elasticity equations for a rotationally symmetric analysis. Several curves showing the temperature and moisture fields and typical displacement and stress distributions are included. The results are useful for studying the growth of holes influenced by moisture and temperature. An environmentally sensitive situation can increase the possibility of unstable growth and the coupling can increase it further.
Protein Stabilization by Removal of Unsatisfied Polar Groups: Computational Approaches and Experimental Tests†

The role of polar and charged side chains in partially buried protein environments has been probed in a variant of Arc repressor (MYL) in which hydrophobic interactions between Met31, Tyr36, and Leu40 replace the wild-type salt-bridge interactions between Arg31, Glu36, and Arg40. In the absence of this salt-bridge triad, three additional side chains were identified by continuum electrostatic calculations as incurring larger desolvation penalties during folding than were recovered in favorable electrostatic interactions in the folded state. These side chains (Asn29, Ser44, and Glu48) were mutated singly and collectively to alanine in the MYL background, and the thermodynamic stabilities of the resulting mutant proteins were found to be increased by 0.1 to 1.3 kcal/mol of dimer. All of the mutants displayed cooperative thermal melts and appeared to have well-packed hydrophobic cores by near-UV circular dichroism spectroscopy, indicating that conformational specificity is maintained. The Arc variant (MYL-NA2...
Evaluation of nitrate analysis using test strips : Comparison with two analytical laboratory methods

Abstract Nitrate remains a contaminant of concern for users of well water. Well‐water evaluation, either to assess nitrate contamination or to evaluate sites prior to including them in a larger water quality study, often involves costly laboratory analysis. A cost effective alternative to laboratory analysis are dip‐style test strips. However, the accuracy of these types of products must be reliable, as failure to identify the contaminant may, for example, persuade a homeowner to neglect to have a potential problem further investigated. The testing of nitrate using such strips typically involves dipping the strip into the water sample and reading the color development after a specific period of time. The color development is then compared to a color scale which corresponds to concentration provided with the test. The results of these types of analysis are especially open to interpretation by the evaluator of the results. An experiment was conducted to evaluate test strips in which individuals or “readers”...
Moving toward knowledge-building communities in health information website design

In this paper, we have described our work with the Arthritis Source website and our efforts to develop a community of learners in that context. We argue that given proper architectural support, efforts to listen to learners can effectively foster collaboration between the authors of an informational website and its visitors and help community building among its users through a dynamic knowledge base.
The McFadyen-Stevens synthesis of aliphatic aldehydes containing α-hydrogens

Flash pyrolytic technique applied to McFayden- Stevens reaction for various simple aliphatic aldehydes
Cytotoxicity and deoxyribonucleic acid damage associated with bromoacetate

Abstract Bromoacetate, one of the hydrolysis products of bromoacetylcholine, has been shown previously to inhibit the growth of neuroblastoma cells in culture. Its mechanism of action is unknown. In this work we have further characterized the cytotoxic effect of bromoacetate in C-1300 neuroblastoma cells in culture and extended it to a cell line not of neural origin, the mouse leukemia L-1210 line. Doses required to inhibit the growth of L-1210 cells in culture were similar to those that inhibited the C-1300 line. Cytotoxicity depended on concentration and duration of exposure. L-1210 colony formation in soft agar was also inhibited by bromoacetate. Bromoacetate was shown to produce DNA single strand breaks in L-1210 cells by the alkaline elution assay. These breaks continued to form after the drug was removed from the medium. Taken together, the toxicity demonstrated toward L-1210 cells and the evidence of DNA damage following drug exposure indicate that the anti-tumor action of bromoacetate may be based on monofunctional alkylation of DNA and not related to inhibition of the cholinergic receptors.
Image composition for object pop-out

We propose a new data-driven framework for novel object detection and segmentation, or “object pop-out”. Traditionally, this task is approached via background subtraction, which requires continuous observation from a stationary camera. Instead, we consider this an image matching problem. We detect novel objects in the scene using an unordered, sparse database of previously captured images of the same general environment. The problem is formulated in a new image composition framework: 1) given an input image, we find a small set of similar matching images; 2) each of the matches is aligned with the input by proposing a set of homography transformations; 3) regions from different transformed matches are stitched together into a single composite image that best matches the input; 4) the difference between the input and the composite is used to “pop-out” new or changed objects.
Creating a Continuum: An Anthropology of Postcompulsory Education

L'auteur etablit ici une approche anthropologique de l'education post-secondaire qui se propose d'augmenter le champ de recherche a un secteur dont il est necessaire de definir la structure et les objectifs.
On the size, shape, and orientation of noctilucent cloud particles

Conclusions about the size of noctilucent cloud particles are often made under the assumption that they are spherical. The small degree of circular polarization observed in the light from noctilucent clouds suggests, however, that the particles may be aligned, and hence nonspherical: unpolarized light is elliptically polarized upon single scattering by aligned particles. Yet no suitable mechanism-aerodynamic, electrical, magnetic-has been proposed which will align small (< 10 μm) mesospheric particles. A more likely explanation for the observed circular polarization is that the light illuminating noctilucent clouds has acquired ellipticity because of multiple scattering in the long atmospheric paths it traverses. Even if noctilucent cloud particles are nonspherical, however, presently accepted upper limits on their size (~0.1 μm) and volumetric scattering need not be revised: scattering by small ice spheres as well as ice ellipsoids of any shape is consistent with the observed angular dependence of the degree of linear polarization. Moreover, particles much larger than 0.1 μm, regardless of shape, will lower the maximum degree of linear polarization below that which has been observed. DOI: 10.1111/j.1600-0889.1983.tb00008.x
Fluxes of living radiolarians and their skeletons along a northeast Pacific transect from coastal upwelling to open ocean waters

Abstract Sinking fluxes of living polycystine and phaeodarian radiolarians and their intact empty skeletons were measured from surface waters to 2000 m using free-floating particle interceptor traps at three sites ranging from highly productive coastal upwelling to oligotrophic central gyre waters in the northeast Pacific Ocean. Total radiolarian fluxes and living pheodarian fluxes were generally highest at the coastal site throughout the water column. There was no consistent site-specific pattern for fluxes of living polycystines, polycystine empty skeletons, and phaeodarian empty skeletons. Living phaeodarians were the only group that showed the same rank order of sites with respect to flux at both the base of the euphotic zone and at 2000 m. Thus different short-term processes occurring in the water column (e.g. destructive and non-destructive predation and midwater addition of living radiolarians) altered radiolarian fluxes. Neither radiolarian fluxes at the base of the euphotic zone nor fluxes at 2000 m showed a simple correspondence with primary production, indicating that short-term measurements did not reveal long-term patterns. At most depths at all sites, fluxes of living, skeleton-bearing phaeodarians outnumbered fluxes of empty phaeodarian skeletons. In contrast, at most depths at all sites, fluxes of empty polycystine skeletons outnumbered fluxes of living, skeleton-bearing polycystines. Relatively large, living skeleton-less phaeodarians were the numerically dominant radiolarian in the uppermost traps at the oceanic and coastal sites. These phaeodarians agglutinate siliceous skeletons of other plankton and contributed 5% of the silicoflagellate flux, 16% of the polycystine flux, and 2% of the centric diatom flux at these depths. The resemblance of skeleton-less phaeodarians to fecal pellets may cause them to be misidentified as fecal material when trap contents are dried for processing.
Rat liver membranes contain a 120 kDa glycoprotein which serves as a substrate for the tyrosine kinases of the receptors for insulin and epidermal growth factor.

Abstract The receptors for insulin and epidermal growth factor possess tyrosine-specific protein kinase activity which may play a role in mediating the biological actions of these two peptides. We have identified a 120 kDa glycoprotein (pp120) in rat liver plasma membranes which can be phosphorylated by the insulin receptor in a cell-free system and in intact cultured hepatoma cells. In the present report, we have demonstrated in a cell-free system that solubilized epidermal growth factor receptors can phosphorylate tyrosine residues inpp120.
The Assessing of Acidophilia with Biebrich Scarlet, Ponceau De Xylidine and Woodstain Scarlet

Horobin and Bennion stated in 1973 that the bonding of Biebrich scarlet at an alkaline pH is hydrophobic as the isomers of Biebrich scarlet (ponceau de xylidine and woodstain scarlet) do not stain at that pH. If correct this would negate the use of Biebrich scarlet as proposed by Spicer and Lillie in 1961 as a measure of acidophilia. We have found all three isomers to stain similarly at an alkaline pH. Goldstein stated in 1963 that Biebrich scarlet saturated with urea stained elastic fibers only faintly or not at all. This we confirmed; we also found that the staining of other acidophilic structures (Paneth cell granules, sperm heads, etc.) was blacked. If only hydrogen bonding and not ionic bonding u blocked in an aqueous dye solution saturated with urea then the exact meaning of alkaline Biebrich scarlet staining is unknown.
Bandless orthodontic bracket

The bandless M bracket protects adhesives that attach orthodontic brackets directly to teeth. Without the M bracket, tested adhesives encountered moisture and integrity of bond was not maintained.
Can time be a discrete dynamical variable

The possibility that time can be regarded as a discrete dynamical variable is examined through all phases of mechanics: from classical mechanics to nonrelativistic quantum mechanics, and to relativistic quantum field theories.
Automated testing of visual instruments and the problem of best focus

We discuss the problem of how to determine the optimum focus during MTF or similar observerless testing of visual instruments. We review the literature to show that the most commonly employed method, maximization of the response at a single spatial frequency, can lead to very large errors in predicting the visual quality of an instrument. We propose alternative criteria, and examine their behavior through focus and in the presence of aberrations. Current data support the assertion that an appropriately defined radius of encircled energy, or an averaged MTF integral, are the best candidates to serve both as general image quality criteria and as a means for determining the optimum focus. We conclude by proposing an experiment that should resolve any remaining questions.
Surface-enhanced Raman Immunoassay (SERIA): detection of Bacillus globigii in ground water

This work presents the development of new methodologies centering on surfaces with immunologically induced affinities for biomaterials in aqueous systems. The immunologically active surfaces concentrate the biomaterials at the interface and therefore eliminate the need for preconcentration steps. This results in a highly sensitive and rapid immunoassay technique. The very strong localized of surface enhanced Raman scattering (SERS) that occurs at noble metal surfaces is combined with the unparalleled selectivity of immunoassays. Localization of the SERS signal eliminates the problem of washing and allows assays to be performed without treatment steps associated with removing excess agents. Previous work with small illicit drug molecules and large microorganisms clearly demonstrates trace detection of species in aqueous environments is possible. This paper discusses further work to detect Bacillus globigii by couping surface enhanced Raman scattering with immunoassays (SERIA) using citrate reduced silver nanoparticles. The spores of B. globigii are used to simulate the behavior of another bacterium that forms spores-the potential biological warfare agent, Bacillus anthracis, the causative agent of anthrax.
Apparent diffusion of water, ions, and small molecules in the Xenopus oocyte is consistent with Brownian displacement

The incoherent displacement of water in living tissues is of considerable interest because of the widespread use of diffusion-weighted MRI, for which image contrast is based on the water apparent diffusion coefficient (ADC). It has been hypothesized that the decrease in water ADC associated with brain injury is primarily due to a reduction in the ADC of water in the intracellular space. Xenopus oocytes permit direct measurement of ADC values for intracellular molecules, thereby providing insight into the nature of intracellular motion. In this study, the measured ADC values of small molecules and ions are shown to be primarily size-dependent, indicating that intracellular water motion in the oocyte is mainly Brownian displacement with little or no role for cytoplasmic streaming. Further, intracellular water ADC values show no dependence on diffusion time over a broad range (3.4-100 ms), suggesting that barriers to displacement are finely spaced (< or = 2-3 microm). The water diffusion shows some small anisotropy, suggesting that the cell has structure, giving water displacement a directional preference. The calculated intracellular apparent viscosity, which reflects the combined effects of barriers to motion, intermolecular binding, and fluid phase viscosity was 2.07 +/- 0.09 cP.
In vivo dynamic deformation of the mitral valve annulus.

Though mitral valve (MV) repair surgical procedures have increased in the United States [Gammie, J. S., et al. Ann. Thorac. Surg. 87(5):1431–1437, 2009; Nowicki, E. R., et al. Am. Heart J. 145(6):1058–1062, 2003], studies suggest that altering MV stress states may have an effect on tissue homeostasis, which could impact the long-term outcome [Accola, K. D., et al. Ann. Thorac. Surg. 79(4):1276–1283, 2005; Fasol, R., et al. Ann. Thorac. Surg. 77(6):1985–1988, 2004; Flameng, W., P. Herijgers, and K. Bogaerts. Circulation 107(12):1609–1613, 2003; Gillinov, A. M., et al. Ann. Thorac. Surg. 69(3):717–721, 2000]. Improved computational modeling that incorporates structural and geometrical data as well as cellular components has the potential to predict such changes; however, the absence of important boundary condition information limits current efforts. In this study, novel high definition in vivo annular kinematic data collected from surgically implanted sonocrystals in sheep was fit to a contiguous 3D spline based on quintic-order hermite shape functions with C2 continuity. From the interpolated displacements, the annular axial strain and strain rate, bending, and twist along the entire annulus were calculated over the cardiac cycle. Axial strain was shown to be regionally and temporally variant with minimum and maximum values of −10 and 4%, respectively, observed. Similarly, regionally and temporally variant strain rate values, up to 100%/s contraction and 120%/s elongation, were observed. Both annular bend and twist data showed little deviation from unity with limited regional variations, indicating that most of the energy for deformation was associated with annular axial strain. The regionally and temporally variant strain/strain rate behavior of the annulus are related to the varied fibrous-muscle structure and contractile behavior of the annulus and surrounding ventricular structures, although specific details are still unavailable. With the high resolution shape and displacement information described in this work, high fidelity boundary conditions can be prescribed in future MV finite element models, leading to new insights into MV function and strategies for repair.
Short-read sequencing for genomic analysis of the brown rot fungus Fibroporia radiculosa.

The feasibility of short-read sequencing for genomic analysis was demonstrated for Fibroporia radiculosa, a copper-tolerant fungus that causes brown rot decay of wood. The effect of read quality on genomic assembly was assessed by filtering Illumina GAIIx reads from a single run of a paired-end library (75-nucleotide read length and 300-bp fragment size) at three different stringency levels and then assembling each data set with Velvet. A simple approach was devised to determine which filter stringency was “best.” Venn diagrams identified the regions containing reads that were used in an assembly but were of a low-enough quality to be removed by a filter. By plotting base quality histograms of reads in this region, we judged whether a filter was too stringent or not stringent enough. Our best assembly had a genome size of 33.6 Mb, an N50 of 65.8 kb for a k-mer of 51, and a maximum contig length of 347 kb. Using GeneMark, 9,262 genes were predicted. TargetP and SignalP analyses showed that among the 1,213 genes with secreted products, 986 had motifs for signal peptides and 227 had motifs for signal anchors. Blast2GO analysis provided functional annotation for 5,407 genes. We identified 29 genes with putative roles in copper tolerance and 73 genes for lignocellulose degradation. A search for homologs of these 102 genes showed that F. radiculosa exhibited more similarity to Postia placenta than Serpula lacrymans. Notable differences were found, however, and their involvements in copper tolerance and wood decay are discussed.
Cystic fibrosis transmembrane conductance regulator: Nucleotide binding to a synthetic peptide

Multiple mutations in the gene responsible for cystic fibrosis are located within a region predicted to encode a nucleotide-binding fold in the amino terminal half of the cystic fibrosis transmembrane conductance regulator protein. A 67-amino acid peptide (P-67) that corresponds to the central region of this putative nucleotide binding site was chemically synthesized and purified. This peptide bound adenine nucleotides. The apparent dissociation constants (Kd's) for the trinitrophenyl (TNP) adenine nucleotides, TNP-adenosine triphosphate, TNP-adenosine diphosphate, and TNP-adenosine monophosphate, were 300 nanomolar, 200 nanomolar, and greater than 1 micromolar, respectively. The Kd for adenosine triphosphate was 300 micromolar. Circular dichroism spectroscopy was used to show that P-67 assumes a predominantly beta sheet structure in solution, a finding that is consistent with secondary structure predictions. On the basis of this information, the phenylalanine at position 508, which is deleted in approximately 70 percent of individuals with cystic fibrosis, was localized to a beta strand within the nucleotide binding peptide. Deletion of this residue is predicted to induce a significant structural change in the beta strand and altered nucleotide binding.
Asthma Prevalence and Risk Factors in Selected Head Start Sites in Chicago

Prevalence of and risk factors for asthma were examined in 1085 Head Start families at 18 Head Start sites in four high-risk community areas in 1994. A total of 13.9% of the families reported diagnosed asthma in their Head Start child and 18.8% reported that their child wheezed in the last 12 months. A total of 26.9% of respondents reported asthma in the immediate family of the child. Low birth weight (1500-2499 g), very low birth weight (<1500 g), and self-reported exposure to dampness or mold in the last 12 months were significantly associated with self-reported diagnosed asthma (OR = 1.93; 95% CI 1.17-8.73), (OR = 4.5; 95% CI 1.25-16.3), and (OR = 1.94; 95% CI 1.23-3.04), respectively. The young age of the children in Head Start, as well as the high prevalence of asthma in their families, suggest that the Head Start programs offer an unusual opportunity for asthma prevention programs.
Switching the Chirality of the Metal Environment Alters the Coordination Mode in Designed Peptides

The effects of switching the chirality of a single layer of amino acids in a three stranded coiled coil has been investigated. X-ray crystallography reveals that this modification is well tolerated and does not alter the designed structure. In contrast, spectroscopic studies of cadmium binding to both the L- and D- enantiomers of the penicillamine, provide evidence that this switch dramatically alters the metal binding capability, the resulting coordination environment and the position of binding.
Identification of cis-elements mediating the stimulation of rat insulin-like growth factor-binding protein-1 promoter activity by dexamethasone, cyclic adenosine 3',5'-monophosphate, and phorbol esters, and inhibition by insulin.

Insulin-like growth factor-binding protein-1 (IGFBP-1) modulates the action of IGFs on target cells. IGFBP-1 transcription is highly regulated by hormonal and metabolic factors. In rat H4-II-E hepatoma cells, IGFBP-1 messenger RNA is stimulated by dexamethasone, cAMP, and phorbol esters, and dominantly inhibited by insulin. To identify the cis-elements that determine transcriptional regulation by these agents, we have coupled rat IGFBP-1 promoter fragments to a luciferase reporter gene and transfected H4-II-E cells using the cationic liposome procedure. Promoter fragments whose 5'-end was at nucleotide (nt) -925 or -327 (with respect to the transcription initiation site, 1) conferred positive regulation of promoter activity by dexamethasone, cAMP, and phorbol esters. Insulin inhibited promoter activity in the presence of any of the three stimulatory agents. Stimulation by cAMP or phorbol esters was abolished when the region between nt -327 and -235 was deleted. Although this region contains potential acti...
Chemotactic factor‐induced generation of superoxide radicals by human neutrophils

Human peripheral neutrophils generated superoxide radicals as assessed by ferricytochrome C reduction in response to activation by the synthetic chemotactic factor, N-formyl-methionyl-leucyl-phenylalanine. Superoxide generation was inhibited by 2-deoxy-D-glucose (ID50 4 X 10(-5)M), 2-iodoacetate (ID50 5 X 10(-5)M), and N-ethyl-maleimide (ID50 5 X 10(-6)M), suggesting a dependence on anaerobic glycolysis and sulfhydryl groups. Ouabain, microtubule-disrupting agents, inhibitors of respiration, oxidative phosphorylation, and protein and nucleic acid synthesis were without appreciable effects. Indomethacin (ID50 1 X 10(-4)M), ibuprofen (ID50 9 X 10(-4)M, and phenylbutazone (ID50 1 X 10(-5)M) all caused dose-dependent inhibition of superoxide generation at concentrations approximating those plasma and tissue levels obtained in human beings at therapeutic doses. Acetylsalicylic acid (125-500) microgram/ml) and aurothioglucose (10(-3)-10(-6)M) were without appreciable effects. Superoxide generation was inhibited only by relatively high concentrations of hydrocortisone (ID50 greater than 10(-3)M). Because superoxide radicals have been implicated in the pathogenesis of tissue injury in several forms of inflammation and arthritis in vivo, these studies suggest that the production of a potential cytotoxic factor may be subject to pharmacologic manipulation and that at least some of the antiphlogistic effects of the nonsteroidal antiinflammatory agents may be mediated through effects on superoxide production.
Past, present and future experiments on muscle

Since the basic outline of the sliding filament mechanism became apparent some 45 years ago, the principal challenge, an experimental one, has been to produce definitive evidence about the detailed molecular mechanisms by which myosin cross-bridges produce force and movement in a muscle. More recently, similar questions could be posed about other molecular motors, in non-muscle cells. This problem proved unexpectedly difficult to solve, in part because of the technical difficulty of obtaining the structural and mechanical information required about rapid events within macromolecules, especially in a working system, and this triggered many remarkable technical developments. There is now very strong evidence for a large change in shape of the myosin heads during ATP hydrolysis, consistent with a lever-arm mechanism. Whether this does indeed provide the driving force for contraction and movement--and, if so, exactly how--and whether some other processes could also play a significant role, is discussed in the light of the experimental and theoretical findings presented at this meeting, and other recent and long-term evidence.
Effect of imperfect detectability on adaptive and conventional sampling: simulated sampling of freshwater mussels in the upper Mississippi River

Adaptive sampling designs are recommended where, as is typical with freshwater mussels, the outcome of interest is rare and clustered. However, the performance of adaptive designs has not been investigated when outcomes are not only rare and clustered but also imperfectly detected. We address this combination of challenges using data simulated to mimic properties of freshwater mussels from a reach of the upper Mississippi River. Simulations were conducted under a range of sample sizes and detection probabilities. Under perfect detection, efficiency of the adaptive sampling design increased relative to the conventional design as sample size increased and as density decreased. Also, the probability of sampling occupied habitat was four times higher for adaptive than conventional sampling of the lowest density population examined. However, imperfect detection resulted in substantial biases in sample means and variances under both adaptive sampling and conventional designs. The efficiency of adaptive sampling declined with decreasing detectability. Also, the probability of encountering an occupied unit during adaptive sampling, relative to conventional sampling declined with decreasing detectability. Thus, the potential gains in the application of adaptive sampling to rare and clustered populations relative to conventional sampling are reduced when detection is imperfect. The results highlight the need to increase or estimate detection to improve performance of conventional and adaptive sampling designs.
From “shattered mummies” to “an epic life”: Casaubon’s key to all mythologies and Dorothea’s mythic renewal in George Eliot’sMiddlemarch

The emergence over the course of George Eliot’sMiddlemarch of Dorothea Brooke as a new sort of epic hero clearly has much to do with her character’s starting point in an ill-suited marriage to the elderly cleric Edward Casaubon. The present paper argues that Casaubon’s unachieved life’s work,The Key to All Mythologies, functions very precisely in the novel as a textual, mythic figure against which, and even through which, Dorothea’s new character is defined.
An investigation of perceived sharpness and sharpness metrics

Sharpness is an important attribute that contributes to the overall impression of image quality. As digital photography becomes more and more popular, digital photo enhancement has been a topic of great interest. In this paper, we investigate two issues related to digital photo sharpness. 1) How do we quantitatively measure the sharpness of a digital image? 2) What is the preferred sharpness of a digital image, and what is the relation between preferred sharpness and sharpness detection threshold? Both issues are of practical use to the digital photography market. First, we present the design and properties of three sharpness metrics to answer the first question. Next, we describe psychophysical experiments to investigate the second question. It is found that 1) the sharpness metric Digital Sharpness Scale (DSS) and Average Edge Transition Slope (AETS) are highly correlated to the perceived sharpness; 2) Both DSS and AETS predict sharpness equality with acceptable error; 3) the sharpness detection threshold is relatively consistent across subjects and across image contents, compared with the sharpness preference; 4) the average level of preferred sharpness is consistently higher than the detection threshold across image contents and across subjects, which implies that observers in general prefer a sharpened image to the original image; and 5) the preferred level of sharpness has a strong dependency on image content.
Assessment of ancestry probabilities in the presence of genotyping errors

This paper extends an approach for estimating the ancestry probability, the probability that an inbred line is an ancestor of a given hybrid, to account for genotyping errors. The effect of such errors on ancestry probability estimates is evaluated through simulation. The simulation study shows that if misclassification is ignored, then ancestry probabilities may be slightly overestimated. The sensitivity of ancestry probability calculations to the assumed genotyping error rate is also assessed.
Experimental studies on photodissociation of HI in crystalline xenon

Abstract The photodissociation of HI at 277 nm in crystalline xenon is followed by monitoring the Xe 2 I exciplexic emission. Above 110 K, the product I atoms diffuse and recombine as I 2 . Between 110 and 80 K dissociation is permanent, and diffusion of I atoms is halted. Below 80 K amorphization of the solid is observed. The inclusion crystals are grown from the melt. Crystallinity is verified by the exciplexic lineshift.
Economic efficiency of agricultural production in Brazil

This study measures levels of technical, allocative and economic efficiency in agricultural crop production for Brazil in 1995. A nonparametric frontier model (DEA) under constant returns to scale was used. On average, the results suggest that the sector suffers from moderate technical inefficiency and from strong allocative inefficiency. If full technical efficiency were achieved, the crop production would increase by more than 30% over that obtained in 1995. Land and labor were overutilized, while fertilizers and pesticides were underutilized. Climate, soil conditions and irrigation use affected technical efficiency levels, and education in rural areas helped explain the extent of allocative efficiency. The state of Sao Paulo State was the only production unit in Brazil operating in full efficiency in 1995.
Constitutive model for densification of corn stover and switchgrass

A constitutive model (i.e., stress–natural strain and strain rate relationship) was developed for predicting and characterising the compression behaviours of corn stover and switchgrass grinds. The constitutive model characterised the biomass as an elasto-visco-plastic solid through five model parameters: elastic modulus, strength coefficient, strain hardening exponent, viscous coefficient, and frictional loss factor. The constitutive model parameters were found to be affected by the densification conditions (i.e., pressure, particle size, moisture content, and preheating temperature). During compression of biomass grinds, the development of structure of the compact inside the die was captured by the elastic modulus. Also, the elastic modulus and viscous coefficient correlated with the compressive strength and durability of briquettes made from corn stover and switchgrass at various densification conditions.
Fecal mutagens and Bacteroides fragilis levels in the feces of dimethylhydrazine-treated rats: influence of diet

Abstract In a study designed to investigate the effects of dietary synergisms on 1,2-dimethylhydrazine (DMH)-induced rat colon carcinogenesis, fecal pellets were examined for the presence of direct-acting fecal mutagens and levels of Bacteroides fragilis group organisms. Intraperitoneal injections of DMH at 10 mg/kg were given for 16 weeks (weeks 3–18) to 160 male F344 rats consuming 4 supplemental dietary factors in all possible combinations. The dietary factors examined were wheat bran (15%), cholesterol (1%), beef tallow (18%) and indole-3-carbinol (IC) (0.1%). Feces were collected 3, 10, 17, 24 and 31 weeks after commencing the dietary treatments and dichloromethane extracts were assayed using the Salmonella typhimurium TA100 without metabolic activation. The numbers of B. fragilis group organisms were enumerated in feces collected at the same time. Most feces samples were negative for mutagens but extracts from weeks 17–31 showed a significant mutagenic response from the IC factor in the diet. The fecal levels of B. fragilis were significantly increased by the inclusion of cholesterol in the diets. The B. fragilis counts and fecal mutagen production were not correlated ( r = 0.09), although species of the B. fragilis group have been implicated in the production on human fecal mutagens.
Comparison of the expression-linked extra copy (ELC) and basic copy (BC) genes of a trypanosome surface antigen.

A recombinant clone of an expression-linked extra copy (ELC) gene of a trypanosome-variable surface glycoprotein was sequenced. In addition the sequences of the corresponding cDNA and portions of the two basic copy genes were determined. Comparison of these sequences reveals that the 5′ boundary of the ELC-transposed segment (2.2 kb) occurs within a repetitive sequence about 700 bp upstream from the start codon of the coding sequence. This sequence does not contain internal symmetries and is not homologous with the repetitive sequence at the 3′ boundary. The first 35 nucleotides of the cDNA are different than the corresponding ELC sequence and presumably were transcribed from another genomic location. A restriction fragment containing predominantly sequences outside of the 5′ boundary hybridizes to a Pst I fragment whose length is variable in different trypanosome clones. This hybridization pattern is similar to that observed using probes for surface glycoprotein genes that are expressed via the nonduplication-associatcd (NDA) mechanism rather than the ELC mechanism. This indicates that there is a sequence correlation between these two DNA rearrangement mechanism.
Mismatch Between the Resting Membrane Potential and the Voltage at Maximum Amplification in Outer Hair Cells (OHCS) of Mammalian Cochlea

OHCs amplify sound by an electromechanical mechanism. Sound-induced vibrations cause OHC membrane potential (E) to change from its resting voltage (Em) to a new value (Em+dE). The induced receptor potential (dE) initiates charge movement (Q) and force production to counteract viscous losses incurred by the traveling wave. Q exhibits a sigmoidal function with E and because it is most sensitive to dE at the midpoint (Vm), Em should equal Vm to ensure maximum amplification. Vm was measured with isolated OHCs extracted from guinea pig with whole-cell patch clamp under constant intracellular pressure in presence of KCNQ4 blocker XE991 (≥ 30 μM) to ensure robust voltage clamp (conductance < 1.5 nS at Vm). After correcting for physiological conditions the results show Vm is coincident with in vitro measurements of Em (Neuron 2011 70: 1143), but a mismatch of 40 mV is apparent when comparing with in vivo measurements of Em made at basal (J. Physiol. 1987 383: 551 and Proc. R. Soc. Lond. B. 1992 247: 97) or apical (J. Neuroscience 1985 5: 1591) regions of cochlea. Results also reveal variation of Vm across the cochlea as a function of a non-uniform charge density of the lateral wall (σ); when σ is uniform Vm is constant, and when σ varies inversely with area of lateral wall (ALW)Vm increases monotonically from a hyperpolarized value at the high frequency region of cochlea to a depolarized value at low frequency region. Although the relationship between Vm and σ is satisfying as it reflects the electric field, the disparity between in vitro and in vivo measurements highlights the need to reconcile them to ascertain the operating position of the amplifier.
IMAIDS: intelligent mobile agent-based intrusion detection system

Peer-to-peer networks provide many advantages over the conventional client-server network architecture. The one primary drawback of the peer-to-peer architecture is the difficulty in maintaining network security. In this paper we propose to use intelligent mobile agents to detect intrusion in peer-to-peer networks. Towards this we have presented two heuristics which will decide the location of agents in a given peer-to-peer network. The goal of our heuristics is to place the agents in the network such that it can detect intrusion as soon as possible, in other words the response time is minimum. The first heuristic finds the location for a single agent. The second heuristic finds the location of multiple agents where each agent is responsible for certain nodes in the network. The second heuristic also assigns nodes to each agent. We have also performed simulation experiments to evaluate the performance of our proposed heuristics.
Finer grain size increases effects of error and changes influence of environmental predictors on species distribution models

Abstract Spatial resolution and zoning affect models and predictions of species distribution models. I compared grain sizes of 90 m grid cells to ecological units of soil polygons (approximately 209 ha composed of discontinuous polygons of 16 ha), and then introduced error into samples and examined influence of topographic and soil variables. I used random forests, which is a machine learning classifier, and open access data. Predictions based on 90 m grid cells were slightly more accurate than coarser-sized polygons, particularly false positive rates (mean values of 0.11 and 0.16, respectively). The trade-off for accuracy was the number of mapping units required to increase resolution. Probability of presence decreased with resolution. Similarly to grain size comparisons, error affected probability of presence more than accuracy of prediction. Unlike grain size comparisons, the relationship between count of each species (i.e., relative abundance) and area predicted as present was lost with addition of error. Introduction of absences into the modeling sample of presences through plot location error increased probability of presence and introduction of presences into the modeling sample of absences through use of background pseudoabsences decreased probability of presence. Finer resolution amplified the effect of background absences; area predicted for presence was reduced by a factor of 5.4 for grid cells and 1.4 for soil polygons. The choice of fine resolution grid cells or coarser shaped polygons resulted in different models, due to varying influence of topographic variables on models. Use of coarser resolution (tens to hundreds of hectares) may be a worthwhile exchange for greater spatial extent of species distribution models and use of ecologically zoned polygons appeared to avoid the modifiable areal unit problem.
Analysis of Debris from the Collision of the Cosmos 2251 and the Iridium 33 Satellites

The collision between the active American Iridium 33 satellite and the retired Russian Cosmos 2251 satellite on 10 February 2009, is the first on-orbit collision between satellites. As of 1 December 2009, the U.S. space tracking system catalogued 1,632 fragments from the collision, many of which will stay in orbit for decades. This paper estimates the total number, size, area-to-mass ratio, and relative velocity of the catalogued fragments; calculates the lifetime and orbital evolution of the fragments; and evaluates the short- and long-term hazards they pose in the space environment. It is shown that previous estimates of the probability that an intact object in space will collide with another object appear to be lower than is indicated by observed collisions. How the collision probability depends on the shapes of the colliding objects is analyzed, and results indicate that including shape dependence will increase estimates of collision probability. Previous analyses have not considered the effects of sa...
Ohio pharmacists' opinions concerning required residency

Abstract Objective To determine the opinion of Ohio pharmacists as it concerns the necessity and value of required residencies for current Doctor of Pharmacy graduates. Methods A self-administered survey was sent to 1000 randomly selected Ohio pharmacists. The survey consisted of 15 items that had to do with residencies and used a Likert scale. Next, nine items used a semantic differential scale to assess opinions of required residencies for hospital, academic, and community pharmacy practice. The study methods were approved by the university's Institutional Review Board. Results A response rate of 44.8% was achieved. The average respondent was a 45-year-old female with a BS degree who worked full time in community practice. Most pharmacists (80.6%) thought that a one-year post graduate residency (PGY1) should not be required for a pharmacist entering community pharmacy. In comparison, 49.9% of pharmacists disagreed or strongly disagreed that a PGY1 residency should be required for a pharmacist entering hospital pharmacy. Respondents in the semantic differential scale indicated that PGY1 residencies were most important for academics (3.06 ± 1.83), then hospital practice (3.13 ± 1.73), and least important for community practice (4.59 ± 1.89). Conclusion Overall, Ohio pharmacists responded that residencies should not be required. Residencies were considered most valuable for academic pharmacists, then hospital pharmacists, and least valuable for community pharmacists. Ohio pharmacists were of the opinion that current Doctor of Pharmacy curricula adequately prepare students to successfully practice pharmacy, and further postgraduate training was not necessary.
Simulation of models involving mixed selfing and random mating : II. Effects of selection and linkage in finite populations.

The joint effects of linkage, inbreeding, and drift due to finite population size were investigated in terms of population changes under selection involving gene interaction. Six-locus models with the same amount of recombination between adjacent pairs of loci, mixed selfing and random mating, and selection of basically three forms (heterotic, optimizing and mixed optimum-heterotic) were used for Monte Carlo simulation. The results were primarily described in terms of certain measures of gene dispersion, genetic variability, gametic unbalance (linkage disequilibrium) and the approach to stable gene frequency equilibria. Under both cumulative and diminutive heterosis models, a steady state with polymorphisms could be attained with random gene dispersion being small and different replicate populations evolved high degrees of gametic unbalance in the direction of excess of either coupling or repulsion phase linkages depending on the random drift in gene frequencies. Under optimum models, on the other hand, all populations approached steady decay toward fixation at all loci although gene dispersion was governed by rather complex interactions between the parameters of selfing, linkage and selection intensity. Gene dispersion was not necessarily proportionately greater with the higher levels of inbreeding. An excess of repulsion linkages with mean population fitness approaching unity was noted in all runs with the optimum models, more so with tight linkage and heavy inbreeding. Any asymmetry in the sense of selection favoring one or the other allele tends to reinforce gene fixation particularly under inbreeding. Heterozygote advantage, on the other hand, seemed to play a relatively greater role under inbreeding in terms of retaining heterozygosity. Mixed optimum-heterotic models provide a favorable compromise between these conflicting attributes of multilocus systems in terms of the maintenance of polymorphisms and the maximization of fitness in relation to certain optimal linked gene complexes. In general, for moderate to large population size these results are, as expected, in line with those reported previously for two-locus deterministic models.
Comprehensive diagnosis of whole-body acid–base and fluid-electrolyte disorders using a mathematical model and whole-body base excess

A mathematical model of whole-body acid–base and fluid-electrolyte balance was used to provide information leading to the diagnosis and fluid-therapy treatment in patients with complex acid–base disorders. Given a set of measured laboratory-chemistry values for a patient, a model of their unique, whole-body chemistry was created. This model predicted deficits or excesses in the masses of Na+, K+, Cl− and H2O as well as the plasma concentration of unknown or unmeasured species, such as ketoacids, in diabetes mellitus. The model further characterized the acid–base disorder by determining the patient’s whole-body base excess and quantitatively partitioning it into ten components, each contributing to the overall disorder. The results of this study showed the importance of a complete set of laboratory measurements to obtain sufficient accuracy of the quantitative diagnosis; having only a minimal set, just pH and PCO2, led to a large scatter in the predicted results. A computer module was created that would allow a clinician to achieve this diagnosis at the bedside. This new diagnostic approach should prove to be valuable in the treatment of the critically ill.