cssi/SciSciGPT-SciSciNet huggingface dataset:
SMECTITE CLAY ADSORPTION OF AFLATOXIN vs. OCTAHEDRAL COMPOSITION AS INDICATED BY FTIR

The fungus Aspergillus flavus Link ex Fries can infect grains and oil seeds and develop Aflatoxin B1 (AfB1) in the fieldor in storage. Aflatoxin contamination is a serious health hazard — it is extremely toxic and hepatocarcinogenic for animals and humans. A practical approach to solve this problem is to use smectite clay as an amendment to animal feed. The objective of this research is to investigate smectite clay—AfB1 interactions by employing Fourier transform infrared (FTIR) spectroscopy to determine how clay composition influences AfB1 adsorption by smectites. When AfB1 was present in the clay, the spectral region from 1800 to 1300 cm−1 was altered, and the regions between 4000 and 1800 and 1300 and 400 cm−1 were unchanged except for the intensity in the broad region near 3400 cm−1 related to the abundance of water. The 1300–400 cm−1 region is attributed only to smectite clay properties, and it relates to the relative adsorption potential of the different smectites. Bonding between AfB1 and smectite clay appears to be in the furan rings. Other possible bonding is with the two oxygens in the coumarin ring of AfB1 and interlayer cations or their associated water molecules. The FTIR evidence of octahedral Fe in smectite and amorphous silica in the clays both indicate greater AfB1 adsorption potential. Other smectites with spectral absorption indicating predominantly Al in the octahedral positions adsorbed less AfB1.
Delayed singularity formation for solutions of nonlinear partial differential equations in higher dimensions.

Abstract Strict solutions u of genuinely nonlinear homogeneous hyperbolic equations in two independent variables with initial data f(x) of compact support become singular after a time interval of order ∥f∥-1. In higher dimensions solutions initially of compact support are likely to have life expectancies of orders ∥f∥-2+e at least. This is proved for the special case of solutions u(x1,..., xn, t) of a second order equation utt = Σi,jaijuxixj, where n ≥ 3 and where the coefficients aij are C∞-functions in the first derivatives of u, forming a symmetric positive definite matrix.
Microfabricated Ice-Detection Sensor

Knowledge of ice conditions on important aircraft lift and control surfaces is critical for safe operation. These conditions can be determined with conventional ice-detection sensors, but these sensors are often expensive, require elaborate installation procedures, and interrupt the airflow. A micromachined, silicon-based, flush-mounted sensor which generates no internal heat has been designed, batch fabricated, packaged, and tested. The sensor is capable of distinguishing between an ice-covered and a clean surface. It employs a bulk micromachined wafer with a 7 micrometers -thick, boron-doped, silicon diaphragm which serves as one plate of a parallel-plate capacitor. This is bonded to a second silicon wafer which contains the fixed electrodes-- one to drive the diaphragm by application of a voltage, the other to measure the deflection by a change in capacitance. The diaphragm sizes ranged from 1 X 1 mm to 3 X 3 mm, and the gap between parallel-plate capacitors is 2 micrometers . A 200 d.c. was applied to the driving electrode which caused the capacitance to increase approximately 0.6 pf--from a nominal capacitance of 0.6 pf--when the surface was ice free. After the sensor was cooled below the freezing point of water, the same voltage range was applied to the drive electrode. The capacitance increased by the same amount. When a drop of water was placed over the diaphragm and allowed to freeze, no change in capacitance was measured, confirming that the diaphragm was locked to the ice layer. Since the sensor uses capacitive actuation, it uses very little power and is an ideal candidate for inclusion in a wireless sensing system.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Natural Nuclear Radiation Environments for the Grand Tour Missions

The solar flare, galactic, and magnetically trapped (Van Allen) nuclear particle radiation environments expected on three outer planet "Grand Tour" missions have been calculated. The missions are the 1977 4-planet mission (Jupiter - Saturn - Uranus - Neptune), the 1977 3-planet mission (Jupiter - Saturn - Pluto), and the 1979 3-planet mission (Jupiter - Uranus - Neptune). The planetary Van Allen belts contribute the largest doses behind 1 gm/cm2 shielding of aluminum. For the 1977 4-planet mission, which passes within 2.6 planet radii of Saturn, Saturn's Van Allen belts may contribute as much as 95% of the total dose of 5300 rads. For the 1977 3-planet mission, which passes within 4.3 planet radii of Jupiter, Jupiter's Van Allen belts contribute 90% of the calculated total dose of 1900 rads. The 1979 3-planet mission dose of 600 rads is due to approximately equal contributions of solar flare particles, galactic (cosmic ray) particles, and Jupiter's Van Allen belts (periapsis at 6.7 Jupiter radii).
Low-loss negative index metamaterials for X, Ku, and K microwave bands

Low-loss, negative-index of refraction metamaterials were designed and tested for X, Ku, and K microwave frequency bands. An S-shaped, split-ring resonator was used as a unit cell to design homogeneous slabs of negative-index metamaterials. Then, the slabs of metamaterials were cut unto prisms to measure experimentally the negative index of refraction of a plane electromagnetic wave. Theoretical simulations using High-Frequency Structural Simulator, a finite element equation solver, were in good agreement with experimental measurements. The negative index of refraction was retrieved from the angle- and frequency-dependence of the transmitted intensity of the microwave beam through the metamaterial prism and compared well to simulations; in addition, near-field electromagnetic intensity mapping was conducted with an infrared camera, and there was also a good match with the simulations for expected frequency ranges for the negative index of refraction.
Covalent modification of DNA by cis-Rh(phen)2Cl2+ upon irradiation in the red region.

Abstract The metal complex, cis-Rh(phen)2Cl2+ (phen=1,10-phenanthroline), absorbs in the near UV region and is apparently transparent in the red region of the electromagnetic radiation. We have previously shown that the chemical can be photosensitized by the red light absorbing dye, methylene blue, and the activated compound forms permanent bonds with DNA. In the present paper we report that despite the negligible absorption of the metal complex beyond UVA (320–400 nm) region, irradiation with red light populates a highly reactive excited state, which forms covalent linkages with DNA. The purified DNA photoadducts indicate binding as high as 105 nmol Rh, which corresponds to 1.8% metal incorporation. The quantum efficiency for covalent binding of Rh complex to DNA with the 633 nm-excitation is in the range of 0.01–0.02 under anaerobic conditions. These data reveal that one Rh atom occurs approximately every 300 DNA bases. HPLC and UV/Vis analyses of the enzymatic digest of the photoadducts support that the DNA–Rh photoadducts are stable to nucleolytic enzymes. The DNA photomodification is inhibited by the presence of oxygen indicating that the new excited state of cis-Rh(phen)2Cl2+ to be different from that populated by UVA excitation.
Comparison of different perfluorocarbons as ultrasound contrast agents.

RATIONALE AND OBJECTIVES: The sonographic properties of Fluosol 20% (F20), which was recently approved for clinical use as an oxygen carrier for coronary angioplasty, were compared to those of perflubron emulsion, which is still in clinical testing. METHODS: Contrast agents were evaluated in 21 normal rabbits divided into three groups of seven rabbits each. All rabbits received 2.7 g/kg of perfluorocarbon (PFC). One group received 2.7 ml/kg of an experimental formulation of perflubron emulsion AF0102, which contains 1 g of PFC in 1 ml of emulsion (P100), the other received 13.5 ml/kg of F20 (1 ml has 0.2 g of PFC), and the third received 13.5 ml/kg of P100 diluted to a 20% concentration (P20). All rabbits were scanned by a blinded sonographer before, during, and immediately after infusion, and then again at 30 minutes and 48 hours. Doppler enhancement, echogenicity of inferior vena cava lumen, echogenic enhancement of perfused tissues, and reticuloendothelial organs were assessed. RESULTS: P100 and P20 had nearly identical sonographic properties at all points. During their vascular phase they enhanced Doppler signal, filled the lumen of the IVC and hepatic veins with flowing echogenic reflectors, and enhanced perfused tissues. F20 had no detectable sonographic effect during its vascular phase. All three emulsions enhanced the liver relative to kidney to a similar degree at 48 hours. CONCLUSIONS: Because RE enhancement was similar for F20, P100, and P20, and because P100 and P20 had similar properties during the vascular phase, the lack of vascular effect of F20 could not be due to the different PFCs used in these agents, or due to the difference in the dilution or volume. The most likely cause for the observed sonographic behavior of F20 and P100 is the difference in emulsion formulation.
"You can exercise your way out of HIV" and other stories: The role of biological knowledge in adolescents' evaluation of myths

A primary objective for science education is to impart robust knowledge that has applicability to real-world problems. This article presents research investigating the relationship between adolescents' conceptual understanding of the biological basis of HIV and critical reasoning. Middle and high school students were interviewed about their understanding of HIV and were subsequently asked to evaluate scenarios that contained myths about HIV. On the basis of their responses to the interview questions, students' understanding of HIV was categorized into three models, naive, intermediate, and advanced. The results indicate that knowledge mediated students' responses in specific ways. Students at different levels of HIV knowledge reasoned in qualitatively different ways about the myths. A significant relationship was found between students' understanding of HIV biology and the level of biological reasoning. We found that students who employed cellular-level biological reasoning were more likely to reject the myths than students who employed just system-level reasoning or nonspecific biological reasoning. The findings emphasize the importance of conceptual understanding in the critical evaluation of information that may serve as a basis for making decisions about HIV. We conclude with discussing the implications of the findings for science and health education. © 2004 Wiley Periodicals, Inc. Sci Ed88:548–573, 2004
Non-axisymmetric buckling of stiffened supercavitating shells: Static and dynamic analysis

Abstract Supercavitating vehicles undergo high longitudinal forces as a result of their high underwater velocity. The drag force compresses axially the body and may cause its buckling. In addition, the time-dependent properties of the cavity generate time-varying longitudinal loads, which are sources of parametric resonances. Static and dynamic buckling need to be considered as limiting factors for the operating speed of this class of vehicles. The stability of supercavitating underwater vehicles is here investigated through a finite element model that predicts the behavior of plain and stiffened shells and is used to obtain stability maps for varying vehicle’s velocity, as well as frequency and amplitude of the force oscillations. Periodically placed circumferential stiffeners are proposed as means to enhance the stability of the considered class of shells. The results indicate the effectiveness of the stiffening rings in extending the range of stable operating conditions, by increasing the critical static buckling loads, and more importantly by reducing the extension of the regions corresponding to dynamic instability.
Evoked Ink Release in Aplysia Produces Inhibition of the Siphon Withdrawal Reflex in Neighboring Conspecifics

Aplysia californica exhibit a dramatic defensive reaction, the release of a cloud of dark purple ink, in response to noxious stimuli. Although the neural control of this behavior has been studied rather extensively, the functional significance of the inking response is not well understood. We have found that ink released by animals that are subjected to noxious stimuli rapidly induces inhibition of the tail-elicited siphon withdrawal reflex in neighboring Aplysia. Further experiments indicated that the inhibitor is the ink itself, and not some other substance released by the donor animals. Finally, we examined whether ink-induced inhibition of siphon withdrawal might be a secondary consequence of an elevated competing response such as increased locomotion. We found that locomotion is not affected by the concentrations of ink we employed, indicating that the ink probably modulates the withdrawal reflex directly. Because the neural circuits responsible for both tail-elicited siphon withdrawal and the inking response have already been partly delineated, one can now bring the neurobiological advantages of Aplysia to bear on the ethologically important issue of signaling between conspecifics.
Magnifying partial image using fractal method

A new method is proposed, in this paper, to magnify a portion of an image based on the fact that fractal attractor has details at every scale. The formulae for magnifying image portions with fractal method are deduced. The fractal codes, the coefficients of a set of contraction mappings, are determined by encoding the portion to be magnified. The fractal codes are then modified according to the formulae deduced in this paper, and the magnified image is obtained by decoding the modified fractal codes. A portion of Lenna image is enlarged by a factor of 8 at both horizontal and vertical directions with 2 methods respectively, one is the new method described and the other is pixel duplication. Experimental results show that the new method is good for partial image magnification with no block effect.
The “positive woman's” journey: A mythic analysis of the rhetoric of stop ERA

By drawing its structural pattern from the romantic quest mythoi and developing characterizations of supporters and opponents which reflect elements of Jung's mother archetype, the rhetorical vision of STOP ERA becomes especially potent and appealing to many American women. The impact of such mythical archetypes is both subtle and pervasive.
Induction of Nitric-oxide Synthase and Activation of NF-κB by Interleukin-12 p40 in Microglial Cells

Interleukin-12 (IL-12) is composed of two different subunits, p40 and p35. Expression of p40 mRNA but not that of p35 mRNA in excessive amount in the central nervous system of patients with multiple sclerosis (MS) suggests that IL-12 p40 may have a role in the pathogenesis of the disease. However, the mode of action of p40 is completely unknown. Because nitric oxide produced from the induction of nitric-oxide synthase (iNOS) also plays a vital role in the pathophysiology of MS, the present study was undertaken to explore the role of p40 in the induction of NO production and the expression of iNOS in microglia. Both IL-12 and p402, the p40 homodimer, dose-dependently induced the production of NO in BV-2 microglial cells. This induction of NO production was accompanied by an induction of iNOS protein and mRNA. Induction of NO production by the expression of mouse p40 cDNA but not that of the mouse p35 cDNA suggests that the p40 but not the p35 subunit of IL-12 is involved in the expression of iNOS. In addition to BV-2 glial cells, p402 also induced the production of NO in mouse primary microglia and peritoneal macrophages. However, both IL-12 and p402 were unable to induce the production of NO in mouse primary astrocytes. Because activation of NF-κB is important for the expression of iNOS, we investigated the effect of p402 on the activation of NF-κB. Induction of the DNA binding as well as the transcriptional activity of NF-κB by p402 and inhibition of p402-induced expression of iNOS by SN50, a cell-permeable peptide carrying the nuclear localization sequence of p50 NF-κB, but not by SN50M, a nonfunctional peptide mutant, suggests that p402 induces the expression of iNOS through the activation of NF-κB. This study delineates a novel role of IL-12 p40 in inducing the expression of iNOS in microglial cells, which may participate in the pathogenesis of neuroinflammatory diseases.
Job Satisfaction and the Parent Worker: The Role of Flexibility and Rewards.

Abstract The purpose of this study was to examine relative differences in the role of facet satisfactions, including a flexibility facet, in explaining overall job satisfaction and intention to quit for parent workers versus non-parent workers. Survey data were collected from a sample of 88 parent workers and 56 non-parent workers from two departments of a large retail company. Results indicated that facet satisfactions affect parent workers and non-parent workers differently. Traditional facet satisfactions were significantly more important in explaining overall satisfaction for non-parent workers than for parent workers. Additionally, the relations between satisfactions with rewards and flexibility and turnover intentions were stronger for parent workers than for non-parent workers; however these two facets were not more strongly related to overall satisfaction for parent versus non-parent workers. These results are discussed in light of theories in the job satisfaction and work-family literatures.
Warm blood cardioplegia: Benefits and risks

Abstract Warm blood cardioplegia has become the hottest topic in myocardial protection since high potassium solutions were popularized in the mid-1970s [1, 2]. This technique has been endorsed with such evangelistic zeal that a recent survey estimated that 10% of practicing cardiac surgeons are now using warm techniques [3]. Unfortunately, this conversion has occurred with more faith than science. There has been a relative paucity of experimental investigations, and clinical protocols in use are imprecise and change month by month. The consequence of this scenario is predictable: when a new procedure has had such dramatic impact, benefits tend to be overstated, complications tend to be minimized, and a "shaking out interval" must occur as surgical science attempts to sort out the "progress" made by surgical art.
Kinetic Study of the Polymerization of Alkyl Vinyl Ethers by HI/12 Catalyst

Abstract The polymerization of alkyl vinyl ethers initiated by hydrogen iodide and iodine catalyst has been studied in detail. The polymerization showed living behavior in nonpolar solvents at low (-15°) temperatures as reported earlier by others. The observed rate of polymerization under the reaction conditions was linearly dependent on the initial concentration of hydrogen iodide and iodine, respectively. However, the monomer concentration did not influence the rate of polymerization (apparent zero order). From the observed rate equation, two possible reaction schemes were proposed and attempts were made to distinguish them by using UV/visible spectroscopy and 13 C-NMR spectroscopy. In both schemes a reversible interaction between monomer and an iodine molecule was postulated as a necessary elemental reaction to fit the observed expression for rate of polymerization. From the spectroscopic analysis results, the interaction between the iodide compound (chain end) and the iodine molecule seems to be very ...
Analysis of factors affecting the spontaneous closure of a gastrocutaneous fistula

Abstract Background/purpose Few reports have documented the rate of persistence of a gastrocutaneous fistula (GCF) after gastrostomy removal or the reason for the persistence of a GCF. The purpose of this report was to analyze a large group of pediatric patients with a persistent GCF to determine the rate of persistence and any factors that correlate with the persistence of a GCF. Methods This was a retrospective review of 1,042 children from The Children's Hospital, Denver, Colorado who had a gastrostomy constructed between 1992 and 2002. The charts of all children with a persistent GCF after gastrostomy catheter removal were analyzed for correlation between 13 clinical parameters and the persistence of a GCF. Results There were 150 children with a persistent GCF for an incidence of 34%. Time elapsed between the creation of the GCF and removal of the gastrostomy appliance (≤8 months versus >8 months) was the only parameter that showed any correlation with persistence of a GCF ( P Conclusions Time was the only factor that determined whether a surgically created GCF would persist after removal of a gastrostomy appliance.
Alternating Minimization Algorithms for Transmission Tomography

A family of alternating minimization algorithms for finding maximum-likelihood estimates of attenuation functions in transmission X-ray tomography is described. The model from which the algorithms are derived includes polyenergetic photon spectra, background events, and nonideal point spread functions. The maximum-likelihood image reconstruction problem is reformulated as a double minimization of the I-divergence. A novel application of the convex decomposition lemma results in an alternating minimization algorithm that monotonically decreases the objective function. Each step of the minimization is in closed form. The family of algorithms includes variations that use ordered subset techniques for increasing the speed of convergence. Simulations demonstrate the ability to correct the cupping artifact due to beam hardening and the ability to reduce streaking artifacts that arise from beam hardening and background events
NMR Characterization of Hairpin Polyamide Complexes with the Minor Groove of DNA

Polyamides containing N-methylimidazole (Im) and N-methylpyrrole (Py) amino acids can be combined in antiparallel side-by-side dimeric complexes for sequence-specific recognition in the minor groove of DNA. Covalently linking polyamide subunits has led to designed ligands with both increased affinity and specificity. Simple aliphatic amino acid linkers serve as internal guide residues for turn vs extended binding in a head-to-tail-linked polyamide motif. Polyamides of sequence composition ImPyPy-X-PyPyPy containing linkers of incremental length (X = 3-aminopropionic acid (β), 4-aminobutyric acid (γ), or 5-aminovaleric acid (δ)) in complex with an undecamer DNA duplex containing a 5'-(A,T)G(A,T)(3)-3' target site were structurally characterized using NMR spectroscopy. Previous quantitative DNase I footprinting studies identified gamma as the highest affinity of these "turn" linkers. NMR titrations and 2D NOESY data combined with restrained molecular modeling reveal that polyamides with β, γ, and δ linkers all may adopt a hairpin structure. Modeling supports the idea that the linkers in the βand δcomplexes adopt an energetically less favorable turn geometry than the γlinker and confirms that the three-carbon γ linker is sufficient and optimal for the hairpin conformation.
Diagnosis and management of diaper dermatitis

This article presents an overview of diaper dermatitis for the pediatric community. The pathogenesis, differential diagnosis, and management of this common condition in infancy are reviewed. This information will assist in making the appropriate diagnosis and managing this irritant contact dermatitis of the diaper area. With conservative management, most cases of irritant diaper dermatitis are self-limited. When the condition persists, one must consider other diagnoses.
Analog signal processing for the thick radiator neutron spectrometer

Abstract The coincedent pulses from the stilbene radiator and the semiconductor recoil counters of a thick radiator telescope are processed on-line using analog techniques to provide a pulse proportional in amplitude to the energy of the neutron initiating the recoil event. Exponentiation amplifiers are used to analog the observed power law behavior of the scintillator response function to internally generated protons. An energy resolution of about 5% is measured for neutrons in the tens of MeV range.
Reagents for the site-specific cleavage of megabase DNA

The physical mapping of chromosomes will be facilitated by methods of breaking large DNA into manageable fragments, or cutting uniquely at genetic markers of interest. Key issues in the design of sequence-specific DNA cleaving reagents are the specificity of binding, the number of different sequences that can be targeted and the cleavage yield.
Research on Study Abroad, Mobility, and Student Exchange in Comparative Education Scholarship

For many years there has been research on study abroad, student mobility and international student exchange; however in the last two decades the volume and scope of this work has increased signific...
Psychophysical Measurement of Cortical Color Mechanisms Not Sensitive to Spatial Frequency

Virsu and Haapasalo report that the Blakemore and Sutton apparent spatial-frequency shift is not color specific. Also supposedly demonstrated is a McCollough effect that is not specific to spatial frequency. It is suggested that inadequate test procedures and a confusion between retinal and cortical adaptation negate these results.
On the impact noise of a drop falling on water

Abstract An analysis is made of the impact sound generated when a water droplet impinges on a nominally smooth air–water interface. Guo and Ffowcs Williams [Journal of Fluid Mechanics 227 (1991) 345–355] derived a mathematical representation of the sound produced in the initial period of impact of duration ⪡ 1 μ s . The theory of this paper is a simple extension of their method that covers all of the effective life time ( ∼ 100 μ s ) of the impact sound pulse. At the acoustic wavefront the predicted pressure signature in the water consists of a large impulsive peak with the directivity of an acoustic monopole source. Behind this peak lower frequency components of the sound are strongly influenced by the effective pressure-release condition on the free surface of the water, and the radiation acquires the characteristics of a much weaker dipole field (with dipole axis normal to the water interface) accompanied by a rapid decrease in wave amplitude. The dipole pressure exhibits a single cycle oscillation before decaying to evanescence about 0.1 ms after the initial impact. Predictions of the acoustic pressure spectral level are shown to be consistent with measurements available in the literature. Applications of the theory are envisaged to situations where the entrainment of air bubbles by droplets is not important, so that the impact is the dominant source of sound—for example, in estimating the contribution to the self-noise of a supercavitating vehicle from ventilating gas containing a ‘spray’ of small droplets impinging on the cavity gas–water interface.
Potential of mean force and pKa profile calculation for a lipid membrane-exposed arginine side chain.

The issue of ionizable protein side chains interacting with lipid membranes has been the focus of much attention since the proposal of the paddle model of voltage-gated ion channels, which suggested multiple arginine (Arg) side chains may move through the hydrocarbon core of a lipid membrane. Recent cell biology experiments have also been interpreted to suggest that these side chains would face only small free energy penalties to cross membranes, challenging a long-standing view in membrane biophysics. Here, we employ side chain analog and transmembrane helix models to determine the free energy of an Arg side chain, as a function of protonation state, across a membrane. We observe high free energy barriers for both the charged and neutral states that would prohibit lipid-exposed movement. The mechanisms for charged and neutral Arg transport are, however, very different, with the neutral state experiencing simple dehydration, whereas the charged state experiences a complex mechanism involving connections to the bilayer interfaces that deform the local membrane structure. We employ special methods to ensure sampling of these interfacial connections and decompose the free energy to shed light on the mechanisms. These deformations are found to preferentially stabilize the protonated form, such that the Arg side chain remains almost exclusively charged inside the membrane, with a pKa shift of <4.5 units. In contrast, the analog models are found to exaggerate the variations in energetics across the membrane and have larger pKa shifts. These results have implications for models of voltage gated ion channels, suggesting that although Arg side chains are ideally suited for carrying charge, the thermodynamics dictate that they must remain sequestered from the lipid bilayer environment.
Monocyclopentadienyl zirconium(IV) complexes

Abstract CpZrCl3·DME (I, Cp = η5-C5H5, DME = 1,2-dimethoxyethane) has been synthesized by reaction of sublimed ZrCl4 and TlCp in DME in 2:1 mole ratio (sublimation of the ZrCl4 is essential). Alternatively, unsolvated, insoluble and presumably polymeric CpZrCl3 is selectively produced by photolysis of Cp2ZrCl2 in Me3CCl. The crystal structure of compound I shows axial-equatorial coordination of the DME ligand. The latter is easily displaced by tetramethylethylenediamine. In contrast to the above results, CpTiCl3 may be recrystallized from DME with no coordination of solvent to titanium.
Is there a "serotonergic syndrome" in neonatal rat pups?

Abstract Neonatal rat pups given the serotonergic agonist quipazine exhibited alterations in the frequency of several behaviors including an increase in mouting, forward locomotion, forelimb paddling, unusual position of limbs (UPL), and a decrease in twitching and lying still. The serotonergic antagonist metergoline potently blocked quipazine-induced mouthing and UPL, and partially attenuated the increase in forward locomoting and decrease in lying still induced by quipazine. Pretreatment with the α-noradrenergic antagonist phentolamine partially attenuated the quipazine-induced increase in mouthing, with both phentolamine and the dopaminergic antagonist haloperidol exhibiting some tendency to suppress the forward locomotion induced by quipazine. Thus, serotonin appears to be most important for the expression of quipazine-induced behaviors in the neonate, although there appears to be some catecholaminergic involvement as well. While quipazine may induce in neonates some components of the adult “serotonergic syndrome” [8], there are some clear age difference in the response patterns. Serotonergically-influenced behaviors seen only early in ontogeny may subserve adaptive functions for the young organism.
Differences in attention, executive functioning, and memory in children with and without ADHD after severe traumatic brain injury.

Although the development of Attention Deficit Hyperactivity Disorder (ADHD) after traumatic brain injury (TBI) has been described, it is unknown whether children with TBI and ADHD have greater neuropsychological impairments than children with TBI alone. This study examines attention, executive functioning, and memory in children with TBI-only and TBI + ADHD. Caregivers of 82 children with severe TBI completed structured psychiatric interviews at enrollment to diagnose premorbid ADHD and one-year after injury to diagnose post-injury ADHD. Children underwent neuropsychological testing one year after injury. One memory measure significantly differentiated children with TBI-only from children with newly developed ADHD [secondary ADHD (S-ADHD)] and those with premorbid ADHD that persisted after injury [persisting ADHD (P-ADHD)]. Compared with the TBI-only group, children with TBI + ADHD had worse performance on measures of attention, executive functioning, and memory. Results reveal that in children with severe TBI, the behavioral diagnosis of ADHD is associated with more difficulty in attention, executive functioning, and memory. Additionally, results suggest greater deficits in memory skills in the S-ADHD group compared with the P-ADHD group. Although findings provide preliminary support for distinguishing P-ADHD from S-ADHD, further research is needed to investigate neuropsychological differences between these subgroups of children with severe TBI. (JINS, 2005, 11, 645–653.)
Protein Carbonylation and Aggregation Precede Neuronal Apoptosis Induced by Partial Glutathione Depletion

While the build-up of oxidized proteins within cells is believed to be toxic, there is currently no evidence linking protein carbonylation and cell death. In the present study, we show that incubation of nPC12 (neuron-like PC12) cells with 50 μM DEM (diethyl maleate) leads to a partial and transient depletion of glutathione (GSH). Concomitant with GSH disappearance there is increased accumulation of PCOs (protein carbonyls) and cell death (both by necrosis and apoptosis). Immunocytochemical studies also revealed a temporal/spatial relationship between carbonylation and cellular apoptosis. In addition, the extent of all three, PCO accumulation, protein aggregation and cell death, augments if oxidized proteins are not removed by proteasomal degradation. Furthermore, the effectiveness of the carbonyl scavengers hydralazine, histidine hydrazide and methoxylamine at preventing cell death identifies PCOs as the toxic species. Experiments using well-characterized apoptosis inhibitors place protein carbonylation downstream of the mitochondrial transition pore opening and upstream of caspase activation. While the study focused mostly on nPC12 cells, experiments in primary neuronal cultures yielded the same results. The findings are also not restricted to DEM-induced cell death, since a similar relationship between carbonylation and apoptosis was found in staurosporine- and buthionine sulfoximine-treated nPC12 cells. In sum, the above results show for the first time a causal relationship between carbonylation, protein aggregation and apoptosis of neurons undergoing oxidative damage. To the best of our knowledge, this is the first study to place direct (oxidative) protein carbonylation within the apoptotic pathway.
The Flight Telerobotic Servicer (FTS) - A focus for automation and robotics on the Space Station

The concept, fundamental design principles, and capabilities of the FTS, a multipurpose telerobotic system for use on the Space Station and Space Shuttle, are discussed. The FTS is intended to assist the crew in the performance of extravehicular tasks; the telerobot will also be used on the Orbital Maneuvering Vehicle to service free-flyer spacecraft. The FTS will be capable of both teleoperation and autonomous operation; eventually it may also utilize ground control. By careful selection of the functional architecture and a modular approach to the hardware and software design, the FTS can accept developments in artificial intelligence and newer, more advanced sensors, such as machine vision and collision avoidance.
Selective Suspension of Single-Walled Carbon Nanotubes Using β-Sheet Polypeptides

Individual single-walled carbon nanotubes (SWNTs) were suspended in water using amphipathic β-sheet peptides of the general sequence Ac-(XKXE)2-NH2. By substituting natural and nonnatural amino acids of varying aromatic and hydrophobic character in the X position, the interactions between the peptide and the nanotube sidewall could be systematically varied. Surprisingly, enhancing the degree of favorable π–π and hydrophobic interactions, which strongly influence the self-assembly properties of these peptides, did not correlate with an improvement in nanotube dispersion efficiency. We found that substituents in the X-position of the peptides play a significant role in SWNT interaction and contributes to (n,m) structure specificity.
Allende inclusions: volatile-element distribution and evidence for incomplete volatilization of presolar solids

Abstract Neutron activation data on 14 trace elements in Allende bulk samples and in fractions of spheroidal Ca-Al-rich inclusions show several distinct distribution patterns. Refractories Ir and Sc have high inclusion/bulk ratios and show little variation with depth. Manganese, Fe, Co, Ni, Ga, Cd and In have low inclusion/bulk ratios and decrease with increasing depth; their presence in the inclusions reflects matrix contamination. Sodium and other alkalies have high inclusion/bulk ratios (near 0.5) and decrease with increasing depth; their high concentration despite moderate volatility seems related to condensation reactions in which refractory Al-bearing minerals are reactants. Chromium, Zn, Ge and Au show patterns similar to those of the alkalies; this seems to indicate that refractory minerals are reactants in their condensation reactions, but thermodynamic support for this hypothesis has not been found. We propose that the large size of Allende spheroidal inclusions indicates an origin by incomplete vaporization of presolar solid matter followed by recondensation of refractories on a limited number of condensation nuclei. The low abundance of large refractory inclusions in ordinary and enstatite chondrites reflects complete vaporization of presolar solids at their formation locations; constraints on homogeneous nucleation resulted in the simultaneous condensation of refractories and olivine at these locations. Quadruplicate analyses of the Orgueil chondrite are in good agreement with previous determinations with the exception of small systematic differences in Au and Ir.
Finding effective compilation sequences

Most modern compilers operate by applying a fixed, program-independent sequence of optimizations to all programs. Compiler writers choose a single "compilation sequence", or perhaps a couple of compilation sequences. In choosing a sequence, they may consider performance of benchmarks or other important codes. These sequences are intended as general-purpose tools, accessible through command-line flags such as -O2 and -O3.Specific compilation sequences make a significant difference in the quality of the generated code, whether compiling for speed, for space, or for other metrics. A single universal compilation sequence does not produce the best results over all programs [8, 10, 29, 32]. Finding an optimal program-specific compilation sequence is difficult because the space of potential sequences is huge and the interactions between optimizations are poorly understood. Moreover, there is no systematic exploration of the costs and benefits of searching for good (i.e., within a certain percentage of optimal) program-specific compilation sequences.In this paper, we perform a large experimental study of the space of compilation sequences over a set of known benchmarks, using our prototype adaptive compiler. Our goal is to characterize these spaces and to determine if it is cost-effective to construct custom compilation sequences. We report on five exhaustive enumerations which demonstrate that 80% of the local minima in the space are within 5 to 10% of the optimal solution. We describe three algorithms tailored to search such spaces and report on experiments that use these algorithms to find good compilation sequences. These experiments suggest that properties observed in the enumerations hold for larger search spaces and larger programs. Our findings indicate that for the cost of 200 to 4,550 compilations, we can find custom sequences that are 15 to 25% better than the human-designed fixed-sequence originally used in our compiler.
Special Collections in College Libraries: The Vertical File

“Pamphlet material has some definite functions in college libraries and therefore should be accorded more consideration than it usually receives. Often librarians give this part of the collection very little thought, sometimes because of lack of time, but more often because they are not interested in such material and they fail to see the values of it.”
Probabilistic 4D trajectory prediction and conflict detection for air traffic control

In this paper, we study the problem of aircraft 4D trajectory prediction and conflict detection which is one of the key functions of the Next Generation Air Transportation System (NextGen). A stochastic linear hybrid system (SLHS) with two different discrete state transition models is proposed to describe the aircraft motion. Based on the SLHS model, a 4D trajectory prediction algorithm is proposed utilizing some prior information about the aircraft's intent. Also, a computationally efficient conflict detection algorithm is developed based on the cumulative distribution function (cdf) approximation for the quadratic form of Gaussian random variables. The performance of the proposed algorithms is validated through an illustrative air traffic scenario.
Increased Single-Photon Emission Computed Tomography Image Processing Speed Achieved in Personal Computers With Memory-Intensive Algorithms

Recent dramatic reductions in the cost of computer random access memory (RAM) and the ability of newer microprocessors and associated personal computer operating systems to address large amounts of memory make novel strategies for high-speed image processing possible. We developed image processing algorithms that use this newly available memory to achieve increases in effective processing speed. These algorithms rely on the use of precomputed lookup tables to avoid repeated use of relatively expensive machine instructions, such as multiplications and divisions. Programs using this strategy to perform single photon emission computer tomography (SPECT) analysis were written in C and assembly language and tested on a Macintosh Quadra 950 (Apple Computer, Cupertino, CA) having 64 megabytes of RAM. The measured processing times are competitive with most dedicated nuclear medicine computers. A general implementation of such programs will allow personal computers to compete with dedicated imaging systems, at a substantial reduction in cost.
The Asymmetry Between Matter and Antimatter

Phase transitions and massive-neutrino decay are two processes that could lead to the preponderance of matter in the universe. Either way, the standard model for particle physics will have to be modified.
Mixing It Up: Measuring Diffusion in Supercooled Liquid Solutions of Methanol and Ethanol at Temperatures near the Glass Transition

Do liquid mixtures, cooled to temperatures below their freezing point, behave as normal liquids? We address this question using nanoscale films of methanol and ethanol supercooled liquid solutions of varying composition (7 -93% methanol) at temperatures near their glass transition,Tg. The permeation of Kr through these films is used to determine the diffusivities of the supercooled liquid mixtures. We find that the temperature dependent diffusivities of the mixtures are well-fit by a Vogel-Fulcher-Tamman equation indicating that the mixtures exhibit fragile behavior at temperatures just above their Tg. Further, for a given temperature, the composition dependent diffusivity is well-fit by a Vignes-type equation, i.e. the diffusivity of any mixture can be predicted using an exponential weighting of the diffusion of the pure methanol and ethanol diffusivities. These results show that deeply supercooled liquid mixtures can be used to provide valuable insight into the properties of normal liquid mixtures.
In vivo binding of 3,3′-dichlorobenzidine to rat and mouse tissue DNA

The kinetics of total DNA adducts were compared in the liver, bladder epithelium and small intestinal epithelium of rats and mice following a single oral dose (100 mg/kg) of 3,3'-dichlorobenzidine [( 14C]DCB). Peak DNA binding (expressed as pmol DCB bound/mg DNA) in rat tissues was 153.5, 144.8 and 36.9 in the intestine, bladder and liver, respectively, whereas in mouse tissues, the binding was 72.5, 58.2 and 55.8, respectively. In either species, the half-life of the DNA adducts in the liver (13.5 and 13.8 days in rats and mice, respectively) was comparable to that in the bladder epithelium (14.8 and 12.7 days in rats and mice, respectively) but longer than that in the intestinal epithelium (5.9 and 4.7 days in rats and mice, respectively). Peak total DCB binding in hepatic but not intestinal or bladder epithelial DNA correlated positively with total urinary DCB metabolites. In vitro, mouse hepatic S9 was 57% more active in catalyzing the formation of DNA-binding derivatives of DCB, in parallel with the higher in in vivo maximum hepatic DNA binding in mice than in rats. Thus, a single oral dose of DCB in rats and mice leads to extensive binding of the chemical to tissue DNA, with the rate of removal of the adducts not differing between target and non-target tissues.
Strain-gage stability measurements for three years at 150°C in air

The zero shifts of nickel-chromium foil strain gages (modified Karma) were measured over a period of three years at a constant temperature of 150°C in air. Three gage lengths were included—1.585 mm (1/16 in.), 3.170 mm (1/8 in.), and 6.340 mm (1/4 in.). The strain gages were bonded to constant-stress cantilever beams which were subjected to nomial mechanical strain levels of 0, ±780 μm/m, and ± 1350 μm/m. Each strian gage was connected by threewire leads to a Wheatstone-bridge circuit for the test duration. The data support two general observations: (1) short gage lengths suffer larger zero shifts than longer gage lengths, and (2) gages in compression suffer large zero shifts than gages in tension. On the assumption that the major cause of the zero shifts is a combination of corrosion of the foil and creep of the gage/epoxy/beam system, the author suggests a possible way to correct for the zero shift by experimentally determining the combined corrosion/creep effect and substracting it from the strain-gage readings. Some of the data appear to be consistent with this assumption, but some of the data do not.
Etiology and management of a mandarin rind disorder in California.

Recent reports of a preharvest rind disorder of Satsuma mandarin fruit resulted in severe crop losses in some growing areas of California (Butte, Fresno, Tulare, and Kern Counties). Symptoms were more frequently observed on fruit on the outer perimeter of the tree and on the exposed side of the fruit. Fungal isolations from affected fruit were inconsistent among orchard sites and growing seasons. Isolations resulted in species of Alternaria, Fusarium, Macrophomina, Ulocladium, and Cladosporium. In laboratory studies, mandarin fruit that were soaked in water for 6 h at 15 to 35°C, air dried, and incubated at 20°C for 3 days developed lesions similar to those observed in the field. When fruit were treated with an agricultural summer spray oil or the antitranspirant di-1-p-menthene prior to water soaking, the incidence and severity of the disorder were significantly reduced. Similar results were obtained in 2 years of field trials at two sites using one to three preharvest applications with the agricultural antitranspirant or summer oil starting after fruit color break. In most trials, a single application of these treatments at 1 or 2 weeks after color break was highly effective. Fungicides were inconsistent in their efficacy, whereas trees that were physically protected from rain did not develop the disorder. These data suggest that this mandarin rind disorder is a physiological, abiotic disorder rather than a pathological problem caused by fungi and can be economically managed with water-repellant treatments.