cssi/SciSciGPT-SciSciNet huggingface dataset:
A Wave Mechanical Approach to the Plasma Interaction Problems

WHEN an object moves rapidly in an ionized gas, its surface, if electrically conducting, will become charged due to the differential in mobilities of the electrons and ions in the gas. Assuming that the medium is in thermodynamic equilibrium and consists of singly charged particles only, the surface will acquire a negative potential. The equilibrium surface potential will be reached when the incident fluxes of electrons and ions become equalized by the biased surface potential. A charged body influences, by electrostatic interaction, the trajectories and concentrations of the neighbouring charged particles which, in turn, modify the potential field by their presence as space charges. This electrodynamic phenomenon, which occurs in the immediate vicinity of a body moving rapidly in a rarefied ionized medium, is the plasma interaction of interest. A variety of scientific experiments have led to the discussion of this problem. As an example we may cite the measurement of the upper ionosphere by the use of a satellite probing scheme. The ionospheric quantities of interest, for example, electron density and temperature, must be inferred from the planned measurements made at the satellite body which is, of course, shielded by a cloud of charged particles and their associated potential field. The theory of measurement, therefore, must be based on an understanding of the specific plasma interaction developed.
Genetic and environmental factors regulating the expression of an extended longevity phenotype in a long lived strain of Drosophila

More than a century ago, August Weismann (1891) asked what factors accounted for the significant differences in life span observed between different species and among different members of the same species. Although Raymond Pearl (1928) and others began developing the answer to his question, the task was soon dropped in favor of more tractable problems in genetics, evolution, embryology, biochemistry and the like. Evolutionary and population genetic investigations allow us to view the life span as an integral part of the life history of an organism and are valuable in that they allow the identification of probable physiological ‘trade-offs’ (Kirkwood & Rose, 1991). Although such evolutionary analyses permit the identification of the fundamental cause of aging, they do not allow one to identify the specific developmental and physiological mechanisms which are actually responsible for the expression of specific lifespans (Clark, 1990; Mayr, 1961; Rose, 1991). Since what appears to be the same phenotype — that of extended longevity — may actually be brought about by different mechanisms, then it becomes important to characterize each set of proximate mechanisms in some detail.
Equine gene mapping: close linkage between the loci for soluble malic enzyme and Xk (Pa).

Summary Resolution of equine soluble malic enzyme phenotypes is greatly improved by isoelectric focusing as compared with starch gel electrophoresis. Phenotype differences can be recognized in plasma as well as haemolysates. The locus for soluble malic enzyme (ME1) is closely linked to the locus for Xk.
Characterization of biocontrol traits in the entomopathogenic nematode Heterorhabditis georgiana (Kesha strain), and phylogenetic analysis of the nematode’s symbiotic bacteria

Abstract Our objective was to estimate the biocontrol potential of the recently discovered entomopathogenic nematode species Heterorhabditis georgiana (Kesha strain). Additionally, we conducted a phylogenetic characterization of the nematode’s symbiotic bacterium. In laboratory experiments, we compared H. georgiana to other entomopathogenic nematodes for virulence, environmental tolerance (to heat, desiccation, and cold), and host seeking ability. Virulence assays targeted Acheta domesticus, Agrotis ipsilon, Diaprepes abbreviatus, Musca domestica, Plodia interpunctella, Solenopsis invicta, and Tenebrio molitor. Each assay included H. georgiana and five or six of the following species: Heterorhabditis floridensis, Heterorhabditis indica, Heterorhabditis mexicana, Steinernema carpocapsae, Steinernema feltiae, Steinernema rarum, and Steinernema riobrave. Environmental tolerance assays included Heterorhabditis bacteriophora, H. georgiana, H. indica, S. carpocapsae, S. feltiae, and S. riobrave (except cold tolerance did not include S. carpocapsae or S. riobrave). Host seeking ability was assessed in H. bacteriophora, H. georgiana, S. carpocapsae, and Steinernema glaseri, all of which showed positive orientation to the host with S. glaseri having greater movement toward the host than S. carpocapsae (and the heterorhabditids being intermediate). Temperature range data (tested at 10, 13, 17, 25, 30 and 35 °C) indicated that H. georgiana can infect Galleria mellonella between 13 and 35 °C (with higher infection at 17–30 °C), and could reproduce between 17 and 30 °C (with higher nematode yields at 25 °C). Compared with other nematode species, H. georgiana expressed low or intermediate capabilities in all virulence and environmental tolerance assays indicating a relatively low biocontrol potential. Some novel observations resulted from comparisons among other species tested. In virulence assays, H. indica caused the highest mortality in P. interpunctella followed by S. riobrave; S. carpocapsae caused the highest mortality in A. domesticus followed by H. indica; and S. riobrave was the most virulent nematode to S. invicta. In cold tolerance, S. feltiae exhibited superior ability to cause mortality in G. mellonella (100%) at 10 °C, yet H. bacteriophora and H. georgiana exhibited the ability to produce attenuated infections at 10 °C, i.e., the infections resumed and produced mortality at 25 °C. In contrast, H. indica did not show an ability to cause attenuated infections. Based on the phylogenetic analysis, the bacterium associated with H. georgiana was identified as Photorhabdus luminescens akhurstii.
“I've always suffered from sirens'’: The cinema vamp and Djuna Barnes’ Nightwood

The most important source for Robin Vote, the heroine of Djuna Barnes’ modernist novel, Nightwood (1936), is the vamp, whose heyday in the middle teens was also the period of Barnes’ highest productivity as a newspaper journalist. The vamp, as full‐grown femme fatale and “wild child,” appeared first in her early feature articles, later in short plays, stories, and poems. These and her stylish pen and ink sketches of vamps established her reputation as a “specialist.” She was one of the first to note that “vamping” was a habit of mind as well as a mode of fashion. Barnes’ interest in both manifestations of the vamp craze powered her conception of Robin Vote, a vamp malgre lui.
Reduced Uromucoid Excretion in the Elderly

COLLEAGUES Clinicians performing routine urine microscopy have long been aware of the presence of urinary slime or uromucoid. Recently, Orskov et al. [1] have shown that uromucoid, a glycoprotein, is identical or nearly identical to Tamm-Horsfall protein produced in the ascending limb of the loop of Henle. A biologic function for uromucoid has not been established; however, strains of Escherichia coli expressing type I fimbriae specifically adhere to urinary mucus in its extracellular free form as well as when coating uroepithelial cells [2]. Not surprisingly, therefore, uromucoid was shown to be rich in mannose residues that serve as oligosaccharide receptors for the almost universally found type I fimbriae of E. coli. Accordingly, it has been suggested that when bacteria enter the urinary tract and carry only type I fimbriae, they might be captured by the free mucus and removed from the urinary tract upon micturition [2]. Thus, uromucoid would act as a host defence mechanism against urinary tract infection.
Inverse compensation for hysteresis in magnetostrictive transducers

This paper addresses the development of inverse compensation techniques for a class of ferromagnetic transducers including magnetostrictive actuators. If unaccommodated, the hysteresis and nonlinear dynamics can produce severe loss of control authority and potential instabilities when the actuators are incorporated in control design. In this work, hysteresis is modeled through the domain wall theory originally proposed by Jiles and Atherton [1]. This model is based on the quantification of the energy required to translate domain walls pinned at inclusions in the material with the magnetization at a given field level specified through the solution of an ordinary differential equation. A complementary differential equation is then employed to compute the inverse which can be used to compensate for hysteresis and nonlinear dynamics in control design. The performance of the inverse compensator and its employment in LQR control design are illustrated through numerical examples.
Magnetic field effects and the role of spin states in singlet fission

Singlet fission is a photophysical process that has promise for increasing the efficiency of solar cells. The dynamics depend on triplet spin states and can be influenced by external magnetic fields. In 4-electron systems, fission takes an initial singlet state into a superposition of triplet pair states. Direct evidence for this superposition state is provided by quantum beats in the delayed fluorescence of tetracene crystals. The beat frequencies depend on crystal orientation with respect to the magnetic field, consistent with predictions based on solving the full spin Hamiltonian. Magnetic field effects on the kinetics are analyzed in terms of a hybrid quantum-kinetic model. The magnetic field has no effect on the initial fluorescence decay rate but affects the decay after the triplet pair states begin to equilibrate with the singlets. The long-time behavior of the fluorescence decay reflects association and separation of triplet pairs and relaxation into different spin states.
Traumatic spondyloptosis resulting from high-energy trauma concurrent with a tonic-clonic seizure

Abstract Background context Traumatic lumbosacral dislocation injuries are rare, high-energy injuries that are challenging to surgically manage. Purpose To report a patient with a traumatic spondyloptosis of L5 on S1 as a result of bilateral pedicle fractures of L4 and L5 occurring during a motor vehicle accident, concurrent with a tonic-clonic seizure. The mechanism and treatment of the injury are discussed. Study design Clinical case report and literature review. Methods A staged circumferential fusion was performed with posterior reduction of L5 to the sacrum and instrumentation and fusion from L2 to the pelvis, followed 12 days later by anterior diskectomies and arthrodesis from L3 to S1. Results Near anatomic reduction and solid fusion were obtained and maintained at 3-year follow-up. The patient remained neurologically intact in all lumbosacral roots throughout the course of treatment. Conclusions The injury pattern described is quite rare. This case of multilevel, bilateral pedicle fracture with traumatic L5–S1 spondyloptosis was successfully treated by circumferential reduction and arthrodesis without neurological injury.
The transient behavior of weldpools with a deformed free surface

Abstract Transient heat transfer, fluid flow and phase change in a weldpool with a deformed free surface are modelled using a two-dimensional coordinate transformation. The theoretical approach makes it possible to accurately model high Marangoni number flows even when the free surface is not horizontal. The method is used to examine the role of surface deformation and surface tension forces in controlling weld penetration during cathode spot welding of steel and aluminum. The calculated flow fields, temperature distributions and weldpool shapes are consistent with experimental findings, and are in reasonable agreement with previously published modelling efforts.
Afferents to the rat caudoputamen studied with horseradish peroxidase. An evaluation of a retrograde neuroanatomical research method

The potential for using the physiologically occurring retrograde axonal transport of protein as a neuroanatomical tool for identifying the origin of neuronal connections within the adult central nervous system has been evaluated for the case of the rat caudoputamen. Following injections of a marker protein, in this case horseradish peroxidase (HRP), centering on but not limited solely to the caudoputamen, peroxidase labeled cell bodies could be identified in several cell territories known or thought to contain afferents to this structure. These included the pars compacta of the substantia nigra, the intralaminar and parafascicular nuclei of the thalamus, and the dorsal nucleus of the midbrain raphe. In cases where only the caudoputamen and external segment of the globus pallidus were labeled directly at the injection site, no peroxidase- containing cells could be identified in the neocortex or in the thalamus outside the intralaminar and parafascicular nuclei. The evidence presented suggests first, that the degree of localization at the injection site is compatible with approaching some problems in neuroanatomy; second, that anterograde transport of the marker protein, if it occurs, does not appear to confound the interpretation of retrogradely labeled cell bodies; third, that many, though not all, afferent cell populations can be identified; and fourth, that labeling by axons in passage does not appear to be a problem. A detailed description of the method, abilities and limitations of the technique, and sources of misinterpretation are also provided.
Is calpain activity regulated by membranes and autolysis or by calcium and calpastatin

Abstract Although the Ca(2+)-dependent proteinase (calpain) system has been found in every vertebrate cell that has been examined for its presence and has been detected in Drosophila and parasites, the physiological function(s) of this system remains unclear. Calpain activity has been associated with cleavages that alter regulation of various enzyme activities, with remodeling or disassembly of the cell cytoskeleton, and with cleavages of hormone receptors. The mechanism regulating activity of the calpain system in vivo also is unknown. It has been proposed that binding of the calpains to phospholipid in a cell membrane lowers the Ca2+ concentration, [Ca2+], required for the calpains to autolyze, and that autolysis converts an inactive proenzyme into an active protease. Recent studies, however, show that the calpains bind to specific proteins and not to phospholipids, and that binding to cell membranes does not affect the [Ca2+] required for autolysis. It seems likely that calpain activity is regulated by binding of Ca2+ to specific sites on the calpain molecule, with binding to each site eliciting a response (proteolytic activity, calpastatin binding, etc.) specific for that site. Regulation must also involve an, as yet, undiscovered mechanism that increases the affinity of the Ca(2+)-binding sites for Ca2+.
Geometric effects on thermoelastic damping in MEMS resonators

The effects of geometry on the energy dissipation induced by thermoelastic damping in MEMS resonators are investigated numerically using a finite element formulation. The perturbation analysis is applied to derive a linear eigenvalue equation for the exponentially decaying rate of the mechanical oscillation. The analysis also involves a Fourier method that reduces the dimensionality of the problem and considerably improves the computational efficiency. The method is first validated by comparing the two-dimensional model to the existing analytical solutions for a simply supported beam system, and then it is extended to a three-dimensional axisymmetric geometry to obtain the energy loss as a function of the geometric parameters in a silicon ring resonator. The computational results reveal that there is a peak value for the resonant frequency when the radial width of the ring varies. In addition, the quality factor (Q-factor) decreases with the radial width as a monotonic function.
Field effect enhancement of thermoluminescence

Abstract Experiments are described in which average fields of the order of 105 V/cm, applied to powder phosphors, produce an enhancement of thermoluminescence by factors of 100 and more. The enhancement arises in all likelihood from the acceleration of thermally released electrons and subsequent impact ionization. The constancy of the enhancement factors enables the effect to be used for dosimetric purposes.
Improved Intrinsic Motion Detection Using Time-of-Flight PET

Intrinsic or data-driven respiratory and cardiac motion detection often track the center-of-mass (COM) change in PET data to derive a motion gating signal. The effectiveness of this method depends on the contrast of the moving target to the relatively stationary background. The stationary background leads to a reduced COM displacement in PET data. Further, the COM calculated using axially truncated PET data is biased. To improve intrinsic motion detection for motion compensated image reconstruction, we use the time-of-flight (TOF) PET data of the original object $f(x)$ to calculate the non-TOF PET data of a volume-of-interest (VOI) weighted object $f(x)w(x)$ . The VOI-weighting $w(x)$ can be chosen to reduce contribution from the stationary background. The reduced background in $f(x)w(x)$ leads to an observed increase in the COM displacement. We also derive rebinning equations to obtain the exact axial COM using axially truncated PET data. To assess the quality of the motion gating signal, we analyze the variance property of the COM using different methods, including with(out) VOI weighting and with(out) compensation for axial data truncation. Analytical simulations, phantom and patient data demonstrate the effectiveness of the proposed approach in identifying the motion phase and in deriving a gating signal to be used for motion-compensated image reconstruction.
Criminal history in schizophrenia: associations with substance use and disorganized symptoms

Many with schizophrenia tend to experience problems with the legal system. Yet little is still known about the correlates of the history of incarceration, as well as frequency of misdemeanor and felony convictions within community samples. To explore this question, we gathered legal and substance abuse histories, and assessments of symptoms and neurocognitive function from 96 adults in a nonacute phase of schizophrenia. ANOVA revealed history of incarceration to be linked with more severe drug and alcohol abuse histories, and greater positive symptoms. Greater numbers of misdemeanor convictions were linked to more severe drug and alcohol abuse histories and greater levels of disorganized symptoms, whereas a greater number of felony convictions was only associated with more severe drug abuse histories. A stepwise multiple regression revealed that both the severity of severe drug abuse histories and levels of disorganized symptoms contributed to predicting 24% of the variance in the number of reported lifet...
Decreased response to recall antigens is associated with depressed costimulatory receptor expression in septic critically ill patients

Anti-inflammatory substances are released during septic shock that modulate monocyte function. Decreased monocyte responsiveness to bacterial toxins and decreased expression of human-leukocyte-associated antigen-DR (HLA-DR) have been reported during septic shock and critical illness. Impaired antigen presentation has been inferred from these observations but has not been demonstrated. We assessed antigen presentation and costimulatory molecule expression in 12 age-matched control subjects, 10 noninfected critically ill patients (CINS), and 17 critically ill patients with sepsis (CIS). Antigen presentation was assessed by using in vitro lymphocyte 5-bromo-2-deoxyuridine (BrdU) incorporation in response to tetanus toxoid. The expression of HLA-DR and the costimulatory molecules CD28, CD86, and CTLA-4 was assessed by flow cytometry. Serum interleukin-10 (IL-10) was also measured by enzyme-linked immunosorbent assay. Serum IL-10 levels were significantly elevated in CIS patients (91 +/- 38 pg/mL) as compared with levels in control subjects (5 +/- 4 pg/mL)(P < .05). Lymphocyte BrdU incorporation increased by 710% +/- 243% in control subjects but by only 144% +/- 62% in CIS patients and 76% +/- 31% in CINS patients (P < .01 vs control). Monocyte HLA-DR expression, monocyte CD86 expression, and lymphocyte CD28 expression were significantly decreased in CIS patients (P < .01) as compared with control subjects. Conversely, lymphocyte CTLA-4 expression was significantly increased in CIS patients (P < .05 vs control). Monocyte CD86 expression was also significantly decreased in CINS patients as compared with control subjects. These data indicate that antigen presentation is decreased in critically ill patients with sepsis. This appears in part related to decreased expression of HLA-DR and the costimulatory molecules CD86 and CD28. Increased expression of the negative signal receptor CTLA-4 may also impair antigen presentation in patients with sepsis.
Leukocyte Count Is Associated With Aortic Arch Plaque Thickness

Background and Purpose—Leukocyte count has been associated with cardiovascular and cerebrovascular disease, including carotid plaque thickness, in several studies. We hypothesized that white blood cell count is associated with aortic arch plaque thickness (AAPT). Methods—Leukocyte count was measured in randomly selected stroke-free community participants undergoing transesophageal echocardiography. AAPT was measured for each subject and dichotomized into 4 and 4 mm (thick plaque). Multivariate linear and logistic regression was used to calculate the effect of leukocyte count on AAPT after adjustment for potential confounding factors. Mean age of the 145 participants was 68.58.3 years; 43.5% were women; 15.9% were white; 31.7% were black; and 49.0% were Hispanic. Results—Mean leukocyte count was 5.881.7610 9 /L. Each unit increase in leukocyte count was associated with a mean 0.28-mm increase in AAPT (P0.0036). After adjustment for other atherosclerosis risk factors, including age, sex, hypertension, diabetes, hyperlipidemia, and smoking, the relationship persisted (mean increase in AAPT, 0.24 mm; P0.0064). Thirty-five participants (24.1%) had AAPT 4 mm. Mean leukocyte count among those with thick plaque was significantly higher than among those with plaque 4 mm (6.541.60 versus 5.651.7610 9 /L, respectively; P0.009). Each unit increase in leukocyte count was associated with an increased risk of thick plaque (adjusted odds ratio, 1.38; 95% CI, 1.05 to 1.79). The relationships were similar for men and women and for those 70 or 70 years of age. Conclusions—Leukocyte count is associated with AAPT and is specifically correlated with AAPT 4 mm, a degree of thickening associated with increased stroke risk. These findings are consistent with current hypotheses regarding the inflammatory or infectious etiology of risk of atherosclerosis and stroke. (Stroke. 2002;33:2587-2592.)
Tissue-specific Leptin promoter DNA methylation is associated with maternal and infant perinatal factors

Leptin a regulator of body weight is involved in reproductive and developmental functions. Leptin promoter DNA methylation (LEP) regulates gene expression in a tissue-specific manner and has been linked to adverse pregnancy outcomes. In non-pathologic human pregnancies, we assessed LEP methylation, genotyped the single nucleotide polymorphism (SNP) rs2167270 in placental (n=81), maternal and cord blood samples (n=60), and examined the association between methylation, genotype, and perinatal factors. Maternal blood LEP methylation was lower in pre-pregnancy obese women (P=0.01). Cord blood LEP methylation was higher in small for gestational age (SGA) (P=4.6×10(-3)) and A/A genotype (P=1.6×10(-4)), lower (-1.47, P=0.03) in infants born to pre-pregnancy obese mothers and correlated (P=0.01) with maternal blood LEP. Gender was associated with placental LEP methylation (P=0.05). These results suggest that LEP epigenetic control may be influenced by perinatal factors including: maternal obesity, infant growth, genotype and gender in a tissue-specific manner and may have multigenerational implications.
Impact of Erbium-Doped Silicon Nanocrystals on the Properties of Polyphenylene Vinylene Films

This report describes the fabrication and properties of composite films composed of poly(phenylene vinylene) (PPV) and Er-doped Si nanocrystals. For these hybrid nanocrystal/polymer materials, preliminary results have focused on their characterization via atomic force microscopy (AFM), profilometry, absorption/fluorescence spectroscopy, and current-voltage measurements. In general, it is found that the presence of Er-doped Si nanoparticles in the film strongly impacts the steady-state photoluminescence of the PPV, whereas the presence or absence of solvent chosen for the nanocrystals influences the carrier transport and resultant visible electroluminescence of light-emitting diodes fabricated from these materials.
Integration of the soil and water assessment tool with the information system in watersheds modeling

Geographic Information Systems have become indispensable tools for watershed-scale hydrologic analysis and modeling. The integrative capabilities of GIS can emulate real-world complexity, facilitating interdisciplinary research and communication. Landsat Thermal Mapper raster images represent topography, land use, land cover, as well as spatial data of surface and ground water hydrology, weather, and soils types are all integrated in GIS themes such as views, tables, charts, and layouts. GIS is being used in data visualization, processing, and management. This paper presents a case study on the integration between the Geographical Resources and Assessment Support System (GRASS) and the distributed parameter and physical process watershed model, Soil and Water Assessment Tool (SWAT) for the management of land practices. This integration proved to be effective and efficient for input data extraction and management for simulating the baseline conditions as well as other scenarios. SWAT is capable of continuous time simulation and flexible domain delineation. The spatial distribution of SWAT output results was successfully presented by using Geomedia-Intergraph software. By using SWAT-Geomedia integration, areas under sever water quality problems could be identified. Sediment and nutrients loads were studied in order to determine a better management of surface water resources in large agricultural watershed.
SO2 and its metabolite: Effects on mammalian egg chromosomes

Abstract The ubiquity of sulfur dioxide as an air pollutant combined with reports of effects of the gas and its blood metabolite on DNA and chromosomes, prompted a study of possible mutagen action on mammalian oocytes. Utilizing in vitro and in vivo systems, mouse, ewe, and cow oocytes were examined for cytologic evidence of structural or numerical damage in meiosis. Fragmentation with rearrangement seen at M1 and M2 and anaphase lagging seen in vitro in each species are classically known to be etiologic in chromosome abnormalities and must be considered, especially in contaminated areas with foci of fetal loss involving ewe and cow.
The human action image and its application to motion recognition

Recognizing a person's motion is intuitive for humans but represents a challenging problem in machine vision. In this paper, we present a multi-disciplinary framework for recognizing human actions. We develop a novel descriptor, the Human Action Image (HAI), a physically-significant, compact representation for the motion of a person, which we derive from Hamilton's Action. We prove the additivity of Hamilton's Action in order to formulate the HAI and then embed the HAI as the Motion Energy Pathway of the Neuro-biological model of motion recognition. The Form Pathway is modelled using existing low-level feature descriptors based on shape and appearance. Finally, we propose a Weighted Integration (WI) methodology to combine the two pathways via statistical Hypothesis Testing using the bootstrap to do the final recognition. Experimental validation of the theory is provided on the well-known Weizmann and USF Gait datasets.
Women Pursuing Careers in Trades and Construction

The purpose of this article is to review the extant literature on women in skilled trades and construction to identify specific gaps in our knowledge of the career development processes and needs of this understudied and underserved population. Our aim is to stimulate the interest of scholars and their engagement in research and practice relevant to noncollege women with interests in these occupations. Such research is needed to guide successful career interventions, inform public policy, and promote equal opportunity for women in the pursuit of their careers.
Oviposition Site and Food Preference of the Green June Beetle (Coleoptera: Scarabaeidae)

Relative preferences of green June beetle, Cotinis nitida (L.), adults and grubs for different organic fertilizers were determined in field and laboratory choice experiments. Six organic fertilizer treatments (low rate of broiler litter, high rate of broiler litter, cow manure, hay, Milorganite, or no fertilizer [the control]) were applied to sandy-loam soil and exposed to adults in 2.7 by 3.7 by 2.4-m screen cages. More eggs and larvae were found in pots treated with broiler litter (43%), cow manure (23%), and hay (30%) than in pots treated with Milorganite (4%) or no fertilizer (0%). Orientation preferences of third-instar grubs were tested in Y-tube and satellite olfactometers. Of the five treatments (broiler litter, cow manure, hay, Milorganite, and a blank control), preference was greatest for broiler litter and cow manure, but all organic fertilizer treatments were generally preferred over the blank control. These experiments suggest that use of organic fertilizers may result in higher densities of green June beetle grubs both by attracting the ovipositing females, and by acting as a food attractant for the mobile larvae.
Properties of the seeing fibers in the rock lobster: field structure, habituation, attention and distraction.

Abstract The properties of “seeing” fibers in the optic peduncle of the rock lobster Panulirus interrupts (Randall) are described. Sixteen such units, including binocular and multimodal fibers, have been identified. They respond continuously to moving black or white targets. A target stopped in the center part of the excitatory visual field causes a response for up to 30 sec. An object brought into this area during darkness can be seen on illumination, provided the dark period has been short. In most fibers the true “seeing” area is surrounded by a “movement” one. The fibers are unresponsive to moving stripes surrounding the animal, but “see” a dark target on one of its white stripes. The “attention” of the fibers can be distracted by visual events outside the excitatory field. Mechanical stimulation of certain body parts can enhance or inhibit the visual responses. These fibers are suitable input sources for the antennal pointing reaction.
Use of Artificial Intelligence in Well-Test Interpretation

This paper describes techniques for the identification of well-test interpretation models from pressure-derivative data. Artificial intelligence (Al) techniques are used to separate the derivative response from signal and differentiation noise, and a rule-based recognition system characterizes the response using a symbolic representation. The computer's choice of a model is based on the pressure-derivative curve and simulates the visual diagnosis performed by a human expert. The reasoning involved in such a diagnosis uses a symbolic representation of the derivative curve.
Synthesis, Structures and Dynamic Properties of Trimethylene- And Tetramethylene-Bis(CIS-Stilbene-1,2-Dithiolato)Nickel(II)

Abstract The unusual, structurally dynamic behaviour of the Ni(II) dialkyldithiolene Ni[(CH3)2S4Ph4], 1, in solution prompted a study of the related macrocyclic complexes, Ni[(CH2)3S4C4Ph4], 2, and Ni[(CH2)4S4C4Ph4], 3, whose synthesis, structures and dynamic properties in solution are described. Complex 2, isolated as a CHCl3 inclusion compound, crystallizes in space group C2/c with 8 molecules per unit cell, a=29.26(2), b = 8.170(4), c = 30.76(2)A, β = 116.69(6)[ddot]. The complex has the cis-syn configuration with respect to the Ni-S(CH2)- bonds and the coordination geometry of Ni is essentially square planar, with mean Ni-S and Ni-S(CH2) bond lengths of 2.174(4) and 2.162(5)A, respectively. Complex 3 crystallizes in space group P21/n, with 4 molecules per unit cell, a=10.07(1), b=18.22(2) A, c=15.36(2) A, β = 94.56(8)[ddot], and the Ni-S(CH2)- bonds are in the cis-anti-configuration. The mean Ni-S-and Ni-S(CH2) bond lengths are 2.156(5) and 2.153(9) A, respectively. The coordination geometry of Ni is ...
Comparison of splittings used with the conjugate gradient algorithm

We consider several possible criteria for comparing splittings used with the conjugate gradient algorithm. We present sharp upper bounds for the error at each step of the algorithm and compare several widely used splittings with respect to their effect on these sharp upper bounds. We then consider a more stringent comparison test, and present necessary and sufficient conditions for the error at each step with one splitting to be smaller than that with another, for all pairs of corresponding initial guesses.
Effect of chip and bonding defects on the junction temperatures of high-brightness light-emitting diodes

Light-emitting diodes (LEDs) are a strong candidate for the next-generation general illumination applications. LEDs are making great strides in brightness performance and reliability; however, the barrier to widespread use in general illumination still remains the cost (dollars per lumen). LED packaging designers are pushing the LED performance to its limits. This is resulting in increased drive currents and thus the need for lower-thermal-resistance packaging. The efficiency and reliability of solid-state lighting devices strongly depends on successful thermal management, because the junction temperature of the chip is the prime driver for effective operation. As the power density continues to increase, the integrity of the package electrical and thermal interconnects becomes extremely important. Experimental results with high-brightness LED packages show that chip attachment defects can cause significant thermal gradients across the LED chips, leading to premature failures. Perfect chip and interconnect structures for highly conductive substrates showed only a 2 K temperature variation over a chip area of approximately 1 mm2, while defective chips experienced greater than 40 K temperature variations over an identical area. A further numerical study was also carried out with parametric finite-element models to understand the temperature profile variation of the chip active layer due to the bump defects. Finite-element models were utilized to evaluate the effects of hot spots in the chip active layer. The importance of zero defects in one of the more popular interconnect schemes—the epi-down soldered flip-chip configuration—is investigated and demonstrated.
High-Rise Reinforced Concrete Structures: Database-Assisted Design for Wind

Advances in wind pressure measurement and computer technology have made time-domain analyses of wind effects on high-rise structures possible in recent years. Time-domain solutions use aerodynamic and wind climatological databases and provide full phase information on wind-induced response that is lost in the frequency-domain approach; therefore, they can account rigorously for the superposed effects of any number of modes of vibration of any shape; for mode coupling; for wind directionality effects; and for the joint contributions of axial forces, bending moments, and shear forces in interaction equations used for structural design. Unlike the frequency-domain approach, in the time-domain approach, the process of determining wind effects and the structural design process, referred to jointly as database-assisted design (DAD), are integrated, transparent, and fully auditable. The objective of this study is to present the DAD approach as applied to high-rise reinforced concrete (RC) buildings. Given the ti...
Studies on the structure of the postnuclear sheath of water buffalo spermatozoa

Surface replication of chemically treated and sonicated spermatozoa of the Asiatic water buffalo has been utilized to study the relationship of the post-nuclear sheath components to each other and to the plasma membrane. The postnuclear sheath can be considered a complex composed of matrix material, formed elements termed “striations”, and a caudal, posterior ring. These components appear to vary in lability upon being treated by the various reagents and conditions used for disruption. Total removal of postnuclear sheath structures was accomplished after treatment with media containing dithiothreitol. Freeze-etching studies including the use of deep etching conditions support the suggestion that the particulate material comprising the basal striations are in part intramembranous while extending into the postnuclear sheath matrix internally and making contact with (or forming a part of) the surface membrane externally.
Characterization of a dopamine receptor (DA2K) in the kidney inner medulla.

Abstract Dopamine (DA) produces a natriuretic/diuretic response in the kidney by mechanisms that are still not well understood. There is some indication that DA2 receptors may be involved in mediating the effects of DA, but little is known regarding the nature of this receptor in the kidney. Autoradiographic localization of [3H]spiperone, a DA2 antagonist, indicated that high-density binding was restricted to inner medullary collecting ducts (IMCDs). [3H]Spiperone binding was saturable, high affinity (Kd, 17.2 +/- 1.65 nM), and high density (Bmax, 935 +/- 83 fmol per mg of protein). The photosensitive spiperone analogue N-(p-azido-m-[125I]iodophenethyl)spiperone labeled similar sized proteins of Mr = 120,000 in membranes prepared from the kidney inner medulla, striatum, and pituitary. However, the rank-order competition profile for the [3H]spiperone binding in the kidney inner medulla differed from the DA2 receptor in striatum and pituitary and, furthermore, RNA (Northern) blot analyses of kidney inner medullary RNA with brain DA2 receptor oligonucleotide probes were negative. Functionally, DA stimulated prostaglandin E2 production by IMCD cells, an effect that could be blocked by the DA2 antagonist domperidone. These results indicate that the kidney inner medulla expresses a functional DA receptor that may represent a newly identified DA receptor subtype (here designated DA2K). Moreover, these results suggest that the kidney inner medulla may be a significant site at which DA, either directly or indirectly, influences water and electrolyte excretion.
Statement on guidance for genetic counseling in advanced paternal age

In 1996, a practice guideline on genetic counseling for advanced paternal age was published. The current document updates the state of knowledge of advanced paternal age effects on single gene mutations, chromosome anomalies, and complex traits.
Measurement of Aldosterone Secretion Rate by Radioimmunoassay

ABSTRACT The radioimmunoassay for the measurement of aldosterone in plasma (1) has been modified to permit measurement of pH 1 hydrolyzable aldosterone in urine and calculation of aldosterone secretion rate. Between 1/100 and 1/150 of a 24-hr urine specimen is necessary for the assay. Following CH2CI2 extraction, pH 1 hydrolysis is carried out for 24 hr. Purification of the aldosterone extract is achieved by 2 paper chromatographies. The technique can also be modified to permit the determination of urinary aldosterone excretion.
Grain-boundary source/sink behavior for point defects : An atomistic simulation study

Abstract The grain-boundary source and sink strengths for both vacancies and self-interstitials have been determined for columnar nanocrystalline structures of Mo using molecular-dynamics simulation. The microstructures, which are initialized to contain either an over-saturation or under-saturation of one particular point defect species (either vacancies or self-interstitials), are subjected to isothermal annealing at high homologous temperatures (T > 0.75Tm) while the point-defect concentrations are monitored throughout. We clearly observe an exponential approach of the point-defect concentrations to equilibrium, in agreement with classical rate theory. These observed approaches to equilibrium yield grain-boundary source/sink strengths that correlate with analytical solutions that depend solely on the grain size. Finally, we find that grain boundary sinks have an approximately equal affinity, or bias, to vacancies and self-interstitials.
OVI, NV and CIV in the Galactic Halo: II. Velocity-Resolved Observations with the Hubble Space Telescope and Far Ultraviolet Spectroscopic Explorer

We present a survey of N V and O VI (and, where available, C IV) in the Galactic halo, using data from the Far Ultraviolet Spectroscopic Explorer (FUSE) and the Hubble Space Telescope (HST) along 34 sight lines. These ions are usually produced in nonequilibrium processes such as shocks, evaporative interfaces, or rapidly cooling gas, and thus trace the dynamics of the interstellar medium. Searching for global trends in integrated and velocity-resolved column density ratios, we find large variations in most measures, with some evidence for a systematic trend of higher ionization (lower N V/O VI column density ratio) at larger positive line-of-sight velocities. The slopes of log [N(N V)/N(O VI)] per unit velocity range from -0.015 to +0.005, with a mean of -0.0032 ± 0.0022(r) ± 0.0014(sys) dex (km s-1)-1. We compare this data set with models of velocity-resolved high-ion signatures of several common physical structures. The dispersion of the ratios, O VI/N V/C IV, supports the growing belief that no single model can account for hot halo gas, and in fact some models predict much stronger trends than are observed. It is important to understand the signatures of different physical structures to interpret specific lines of sight and future global surveys.
Structure and solvation of melittin in 1,1,1,3,3,3-hexafluoro-2-propanol/water.

Fluorinated alcohols can induce peptides and proteins to take up helical conformations. Nuclear Overhauser effect (NOE) spectroscopy experiments and analysis of CαH proton chemical shifts show that the conformation of melittin in 35% hexafluoro-2-propanol/water is α-helical from residues Ile-2 to Val-8 and from Leu-13 to Gln-25. As has been found in other solvent systems, the two helical regions are not colinear; the interhelix angle (73 ± 15°) in 35% 1,1,1,3,3,3-hexafluoro-2-propanol/water is smaller than the angle found in other fluoroalcohol-water mixtures or in the crystal. Intermolecular 1H{19F} and 1H{1H} nuclear Overhauser effects were used to explore interaction of solvent components with melittin dissolved in this solvent mixture. The NOEs observed indicate that fluoroalcohol and water molecules are both tightly bound to the peptide in the vicinity of the interhelix bend. For the remainder of the molecule, solute-solvent NOEs are consistent with preferential solvation of the peptide by the fluoroalcohol component of the solvent mixture.
Phase Relations in Some Halide Systems

Phase relations in the systems LiF-CdCl2, CdF2-CdCl2, NaF-CdCl2, NaCl-CdCl2, and NaCl-CdF2were studied by the cooling-curve technique with visual observations. The systems LiF-CdCl2and CdF2-CdCl2 showed simple binary eutectics. The compounds NaFCdCl2 and 2NaClCdCl2were observed in the systems NaF-CdCl2 and NaCl-CdCU respectively. It was found that there was reaction between the end members in the system NaCl-CdF2 to give NaF and CdCl2, which then formed the compound NaF.CdCl2.
Intact visual latent inhibition in schizophrenia patients in a within-subject paradigm.

Abstract People are normally slower to learn a CS-UCS association if they first experience the CS without the UCS. This normal slowing, termed “latent inhibition” (LI), is reported by some to be absent in schizophrenia patients. Our previous studies detected generalized learning deficits but not LI deficits in schizophrenia patients, using between-subject auditory and visual LI paradigms. To understand our divergent results, we developed a within-subject visual LI paradigm that detects LI in normal male subjects that we previously reported to be disrupted by acute treatment with dopamine agonists. In the present study, we verified the ability of this dopamine-sensitive within-subject LI paradigm to detect LI among both male and female normal control subjects, and then used this paradigm to assess LI in schizophrenia patients. Among normals, LI exhibited no sex differences or menstrual cyclicity. Compared to normals, schizophrenia patients exhibited learning deficits with both preexposed (PE) and non-preexposed (NPE) stimuli. Despite these generalized deficits, both acutely hospitalized patients and stable outpatients with schizophrenia exhibited robust LI, as evidenced by significantly faster learning with NPE than PE stimuli. LI deficits in schizophrenia may be paradigm-specific and are not detected by a paradigm that we previously reported to be sensitive to disruption by dopamine agonists.
Coordinating Asynchronous and Open Distributed Systems under Semiring-Based Timing Constraints

For asynchronous and open distributed systems, dynamicity, openness, and stringent quality of service requirements pose great challenges to model and develop such systems. The Actor-Role-Coordinator (ARC) model was previously proposed to address these challenges. The role concept in the model addresses the dynamicity and openness issues by providing abstractions of actor behaviors. In this paper, we focus on coordinating actors and roles through message manipulations based on event-based timing constraints. In addition, different types of timing constraints are generalized into a semiring-based constraint structure; and the all-pairs extremal paths algorithm on closed semirings is applied to derive the most stringent constraints which are logical implications of the original set of constraints. The derived implicit constraints are further used to test constraint inclusions and decide intersections between feasible regions of timing constraint sets. The integration of the ARC model and the semiring-based timing constraint models is prototyped using Maude, a rewriting logic language. We further use the proposed approach to solve the Restaurant for Dining Philosophers problem and illustrate the expressiveness of the ARC and the semiring-based timing constraint models for exogenous and composable coordination of open systems.