cssi/SciSciGPT-SciSciNet huggingface dataset:
l-Homoarginine studies provide insight into the antimetabolic properties of l-canavanine

A method for the chemical synthesis of L-homoarginine, based on the guanidination of L-lysine with O-methylisourea, has been developed; this procedure provides radiochemically pure L-[guanidino-14C]homoarginine in high yield. Radiolabeled homoarginine is incorporated readily into the newly synthesized hemolymphic proteins of larvae of the tobacco hornworm, Manduca sexta without adversely affecting larval growth and development. This finding stands in sharp contrast to the effect of L-canavanine, another L-arginine analog, which is markedly deleterious to these larvae. Homoarginine is incorporated into M. sexta lysozyme, and the antibacterial proteins of the fly, Phormia terranovae with impunity. In contrast, the comparable canavanine-containing enzymes are inhibited severely. Experimental evidence is presented that the innocuous nature of homoarginine results from the elevated pKa value of its guanidino group which arguably exceeds even that of arginine. As a result, homoarginine does not disrupt essential residue interactions. In contrast canavanine, which is much less basic than arginine, does adversely affect R group interactions forming the requisite three-dimensional conformation of the protein.
Phospholipid metabolism in neural microvascular endothelial cells after exposure to lead in vitro

Lead (Pb2+) is known to alter the permeability of brain capillaries. A possible mechanism for this alteration may be related to the ability of Pb2+ to substitute for Ca2+. Products derived from phospholipid metabolism, namely eicosanoids and diacylglycerol, control endothelial permeability, are partly regulated by intracellular Ca2+, and thus may be sensitive to Pb2+. We asked in this study whether Pb2+ increased arachidonic acid release or stimulated phosphatidylcholine breakdown in an in vitro model of brain capillaries, namely cultured bovine retinal endothelial (BRE) cells. Pb2+ stimulated arachidonic acid release and phosphatidylcholine and phosphatidylinositol metabolism in the presence of ionomycin, but not by itself. More arachidonic acid was released than phosphorylcholine in BRE cells stimulated with ionomycin and Pb2+, but the magnitudes of these responses were similar in cells exposed to ionomycin plus Ca2+. Ionomycin plus Pb2+ or plus Ca2+ resulted in the activation of phospholipase A2, since an increase in lysophosphatidylcholine and arachidonic acid was observed. Protein kinase C was not required for arachidonic acid release because release was observed in cells with a down-regulated enzyme. Ionomycin plus other metals (La3+, Cd2+, or Mg2+) did not result in arachidonic acid release, but Cd2+ or Co2+ inhibited arachidonic acid release by more than 80% when cells were exposed to ionomycin with either Pb2+ or Ca2+. Thapsigargin or maitotoxin plus Ca2+ increased arachidonic acid release that was inhibited by the receptor-dependent calcium channel antagonist SK&F 96365 but not by the voltage-dependent calcium channel antagonist nifedipine. However, thapsigargin or maitotoxin plus Pb2+ failed to stimulate arachidonic release. Since in this in vitro model Pb2+ stimulated phospholipid metabolism solely in the presence of an ionophore, the increase in permeability observed in Pb2+-exposed animals is probably not due to a release of metabolites of arachidonic acid.
Lifetimes of complexes of the antibiotic X-537A (lasalocid A) with physiological cations in methanol. Determination by NMR using a dissociative shift reagent.

Abstract Using a magnetic resonance method we have determined the lifetimes of the following complexes of X-537A (HX) in methanol solution at 25° C, BaX+, 132 μs; SrX+, 34 μs; CaX+, 24 μs, and KX, 15 μs, each with an estimated uncertainty of 30%. For NaX and LiX the lifetimes are too short to measure by the present method, The lifetime found for BaX+ is considerably shorter than the result obtained by Patel and Shen using a different method. The present method depends upon the broadening of the resonance lines of certain protons in X− due to reactions such as X− + Ba2+ = BaX+, when the resonance of the proton in the “free” X− has been shifted from its normal frequency by Pr(III) which acts via the exchange PrX3 ⇌ PrX+2 + X−. To determine the lifetimes of interest the equations for a three-state spin system were derived; under the relevant conditions the final equations take the form of the Swift-Connick equations for a two-state system, with the characteristics of one of the states dependent upon the PrX3 concentration. This dependence is used to extract the life-times from the data in a novel and simple way.
Influence of microstructure on rock elastic properties

Depending on details of the composite microstructure, different theories may be needed to obtain good agreement with measured elastic properties. This observation is especially pertinent whenever the composite is porous, as is normally true for rocks. Predictions of three theories are compared to data for porous glass samples. The differential effective medium (DEM) theory and Hashin's composite spheres assemblage (H) do a good job of predicting elastic behavior of a porous foam composed of glass. The self-consistent (SC) effective medium theory does equally well at predicting behavior of a sintered glass-bead sample. The realizable microstructure of each theoretical model is a good analog of the microstructure for one or the other of these two very different porous glasses. Velocities of granular rocks such as sandstones may be estimated accurately using the SC theory, whereas velocities of rocks such as basalts having isolated cracks and pores may be better estimated using either the DEM theory or Hashin's model.
Hypersensitivity of mesenteric veins to 5-hydroxytryptamine- and ketanserin-induced reduction of portal pressure in portal hypertensive rats.

Abstract Isolated superior mesenteric veins from portal hypertensive rats were 3 to 10 times more sensitive to 5-hydroxytryptamine (5-HT) and 3 times less sensitive to (-)-noradrenaline than veins from sham-operated rats. The sensitivity to vasopressin did not differ in the 2 groups. Ketanserin competitively antagonized the effects of 5-HT in superior mesenteric veins and portal veins with high affinity (KB values 0.1-0.3 nM), as expected for 5-HT2-receptors. The affinity of ketanserin for 5-HT2-receptors was similar in veins from normal, sham-operated or portal-hypertensive rats. Intraportal injections of low doses of 5-HT caused increases in portal pressure which were more pronounced in portal hypertensive rats than in sham-operated rats and were blocked by 0.3 mg kg-1 ketanserin in both groups. Ketanserin 0.3 mg kg-1 did not block the portal pressor response to (-)-noradrenaline in either group of rats. In portal hypertensive rats but not in sham-operated rats, 0.3 mg kg-1 ketanserin caused decreases in portal pressure, portal flow and cardiac output, as estimated by radioactive microspheres. The reduction in portal pressure caused by ketanserin was due mainly to a decrease in portal venous inflow secondary to a decreased cardiac output. The reduction in cardiac output, which was observed only in the portal hypertensive rats but not in sham-operated rats, is consistent with venous dilatation and pooling of blood in the portal venous system. The venous pooling could be secondary to the blockade of 5-HT2-receptors in the portal venous system. It is proposed that ketanserin should be explored for the treatment of patients with portal hypertension.
Contribution to the probabilistic theory of neural nets: II. Facilitation and threshold phenomena

The output curve of a single neuron with a threshold of response with respect to the frequency of the stimuli is derived. If the stimuli are regularly spaced in time, the output curve has discontinuities. If the threshold and/or refractory period are sufficiently large, the output curve approaches the “all-or-none” curve.
Intraspecific competition in developing Tyrophagus putrescentiae (Acari: Acaridae)

Abstract Intraspecific competition in developing stages of the mite Tyrophagus putrescentiae was examined as a function of initial larval density. When the K-value is plotted against log density the slope had a b-value of infinity. This slope is attributed to scramble competition rather than to contest competition. The developing stages of T. putrescentiae were not influenced by the direct actions of other mites, but instead by the increased difficulty of finding food that has not been used by other mites.
Remote imaging of internal solitons in the coastal ocean

Abstract During a combined in situ and airborne remote sensing exercise off Oceanside, CA, a Compact Airborne Spectrographic Imager (CASI) observed alongshore lineations, which were associated with an internal soliton packet accompanying a tidally generated internal solitary wave (solibore). The soliton packets were most evident in the images at green wavelengths, which penetrate the deepest into the water column, and only weakly evident at optical wavelengths with shallower penetration. We believe that this is the first observation of internal soliton packets determined from remotely sensed upwelled radiance. We hypothesize that the lineations were produced by changes in the upwelling radiance from the interior of the water column, not by changes in surface reflectance. Using a simulation, it is demonstrated that such lineations can be produced by vertical modulation of the inherent optical properties (IOPs) during the passage of the internal soliton packet. Since surface manifestations are not always present, this opens the potential for broadly based inventories of internal solitons in coastal waters.
Hyperthermic intraoperative intraperitoneal chemotherapy for peritoneal carcinomatosis and sarcomatosis using a cardioplegia heat exchanger and a two-pump system: a case report

A 34-year-old male diagnosed with pseudomyxoma peritoneii presented for an exploratory laparotomy and hyperthermic intraoperative intraperitoneal chemotherapy. A circuit using two roller pumps and a cardioplegia administration set was assembled to deliver the chemotherapy perfusate at a consistent temperature. The authors discuss a case in which this treatment modality was used, describing the perfusionist’s role and the circuit design.
A rheological mechanism sufficient to explain the kinetics of cell sorting.

Abstract When two different vertebrate embryonic tissues are dissociated into individual cells, which are then recombined into mixed aggregates, the differing cells sort out within the aggregates to form a characteristic structure. The kinetics of cell sorting closely resembles the kinetics of breaking of an unstable emulsion of two immiscible liquids. We investigate the consequences of the postulate that cell rearrangement in such a system is driven by the tension at the interfaces between the two cell populations and resisted by “tissue viscosities”, the latter being a newly recognized parameter of cell sorting. Using preliminary experimental data on cell population interfacial tensions and on the time for fusion of two identical spherical aggregates, the viscous liquid model leads to estimates for tissue viscosities in the range of 0.4 × 10 6 to 0.7 × 10 8 poise. Also, using two other independent sets of data, one on the time for breaking of a roughly cylindrical cell aggregate into a few clusters, and the other on the time for the rounding-up of an approximately ellipsoidal tissue mass into a roughly spherical mass, tissue viscosities are again estimated to be in the range of 10 6 to 1.5 × 10 8 poise. In attempting to find a possible basis for such high effective viscosities, we propose that: (i) tissue viscosities would most likely result from sliding friction between the cell membranes; (ii) the cell membranes would have to possess protrusions of molecular or macromolecular dimensions; and (iii) the ratio of the surface tension to the logarithm of viscosity should, if this model is correct, be approximately constant, independent of the tissue.
Slow Degradation of Hydrogenated Amorphous Silicon Photoconductivity Under Pulsed Illumination

The authors degraded hydrogenated amorphous silicon (a-Si:H) using red light pulses of 32 microseconds to 2 milliseconds. These metastable photoconductivity degradations were compared to degradation with continuous light of the same intensity and same exposure time. For a given integrated exposure time they observe higher degraded photoconductivities (by up to 40%) as they shorten the pulses. For example, to obtain the same amount of degradation with 120 microsecond pulses as with continuous illumination, the integrated sample exposure time must be doubled. Experiments were conducted to exclude thermal effects. The result cannot be explained with a simple recombination-driven degradation mechanism, because electron and hole populations rise and fall to steady-state values in only a few microseconds. They conclude that carrier recombination creates a more proximate precursor to metastable degradation of a-Si:H. When illumination begins, this precursor's density rises more slowly than the density of photocarriers and therefore degradation is delayed.
Clustering-based roadway segment division for the identification of high-crash locations

This article introduces a clustering approach to roadway segment division, in place of the traditional fixed-length and variable-length division methods, to improve the calibration of safety performance functions (SPFs) for the purpose of identifying high-crash locations. The clustering approach helps to reduce crash heterogeneity for within-group elements by grouping roadway segments with similar crash distributions into homogeneous groups. For comparison purpose, all three segment division methods were applied to a 142.6-kilometer (88.6-mile) stretch of freeway on Interstate 95 that spans three counties in southern Florida in the United States. Using 5 years of crash data occurring on segments generated from each of the three division methods, the corresponding SPFs were calibrated using the negative binomial model. The calibrated SPFs were then used in the empirical Bayes approach of identifying high-crash locations. The results showed that clustering method produced a much better-fitted SPF than that ...
SUSY partners of Majorana neutrinos in lepton number violating processes

Abstract We consider the effects of light supersymmetric partners of Majorana neutrinos in (i) neutrinoless double beta decay and (ii) muonium-antimuonium conversion together with the crossed channel ee → μμ . The first process is unaffected. The second process is dominated by the exchange of such sneutrinos and provides an amplitude two orders of magnitude greater than most previous estimates.
Abstract 2875: Meta-iodo-benzylguanidine (MIBG) is a MYCN/MYC destabilizer that specifically targets neural crest derived tumors

Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL Melanoma and malignant pheochromocytoma are known for high MYC expression. MYCN amplification and its over-expression are associated with the worst neuroblastoma disease outcome. Meta-iodo-benzylguanidine (MIBG) is a norepinephrine analogue and a mitochondrial respiration inhibitor. 131I-MIBG has been used for scintigraphic detection of neural crest derived tumors (neuroblastoma, pheochromocytoma and melanoma) that specifically uptake MIBG by norepinephrine transporters (NET). 131I-MIBG is also used for targeted radiotherapy of neuroblastoma and pheochromocytoma. Non-radiolabeled MIBG had been reported to be cytotoxic to neuroblastoma cells in vitro and in vivo. However, the molecular mechanism of its growth suppressive effect was not elucidated. Our previous studies showed that FCCP, a well-known mitochondrial respiration inhibitor, destabilized MYCN and MYC in neuroblastoma cells and caused growth suppression. In this study we confirmed that MIBG suppressed growth of neuroblastoma cell lines (SKNBE(2)C, IMR5, Nb69, and SKNAS), and its growth suppressive effect in each cell line correlated with NET expression in these cells. In addition, MIBG suppressed growth of neuroblastoma stem cells derived from SKNBE(2)C. MIBG treatment of SKNBE(2)C and SKNAS resulted in an increase expression of growth suppressive gene (GADD45B) and genes encoding for biomarkers of favorable neuroblastoma (CD44, EPHB6, EFNB2, EFNB3, NTRK1). Treatment of MYCN amplified (SKNBE(2)C, IMR5) and non-MYCN amplified (Nb69, SKNAS) neuroblastoma cells with MIBG resulted in marked reduction of MYCN and MYC expression, respectively in dose and time dependent fashions. Collectively, our studies suggest that MIBG not only targets neural crest derived tumors, but also is a MYCN/MYC destabilizing agent. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2875. doi:1538-7445.AM2012-2875
Detection of the formyl radical in a methane/oxygen flame by resonance ionization

Abstract Formyl radicals have been detected in a low-pressure methane/oxygen flame by resonance-enhanced multiphoton ionization (REMPI). Single-photon ionization following two-photon excitation of vibronic subbands near 397 nm of the 3p 2Π(A″)←X2Π(A′) band system of HCO was monitored for measurements of the spatial profile of HCO above the burner. The results exhibit the sensitivity and spatial resolution required for quantitative studies of the role of HCO in hydrocarbon combustion.
Annual production of leaf‐decaying fungi in a woodland stream

1. Fungi are thought to be important mediators of energy flow in the detritus-based food webs of woodland streams. However, until recently, quantitative methods to assess their contribution have been lacking. Growth rates of leaf-decaying fungi can be estimated from rates of acetate incorporation into ergosterol which, together with estimates of fungal biomass from ergosterol concentrations, enables calculation of fungal production. In this study, I used this method to estimate total production of leaf-decaying fungi over an annual cycle in a small woodland stream, Walker Branch, Tennessee, U.S.A. To calculate fungal biomass and production on an areal basis, I determined the amount of leaf litter occurring in the stream by sampling transects randomly selected in each of ten 10-m sections every 20–50 days. Subsamples of leaves chosen from five of the transects were used to determine ergosterol concentrations and in situ rates of acetate incorporation into ergosterol. 2. Leaf litter, fungal biomass m–2, and fungal production m–2 were highly seasonal. Leaf litter ranged from 249 g m–2 in November to less than 5 g m–2 during the summer. Fungal biomass as percentage of leaf litter ranged from 4.4 to 8.8% during the year, but on an areal basis ranged from 11 to 13 g m–2 during November to January to 0.25 g m–2 in June, primarily due to the seasonal variation in amount of leaf litter present. Fungal growth rates averaged 2.6% day–1 (0.9–7.0% day–1) during the year. Daily production of leaf-decaying fungi ranged from 0.49 g m–2 in November, when the amount of leaf litter was at its maximum, to 0.006 g m–2 during the summer when the amount of leaf litter was low. Annual production of leaf-decaying fungi was 34 g m–2, with an annual production to biomass ratio (P/B) of 8.2. 3. Fungal spore concentrations in the stream were also seasonal and were correlated with amount of leaf litter m–2 and fungal biomass m–2. Spore concentrations varied between one and four spores ml–1 throughout most of the year, but increased to eighteen spores ml–1 shortly after the greatest amount of leaf litter was present in the stream during November.
994 NEUTRALIZATION OF HERPES SIMPLEX VIRUS BY ANTIBODY IN AMNIOTIC FLUID

The incidence of natally acquired Herpes simplex infections (HSI) has been estimated to be 1/7500 births, despite the fact that rates of asymptomatic shedding by pregnant women have been shown to be as high as 1/154. To investigate mechanisms which may explain the lower than expected incidence of clinical infection, amniotic fluid (AF) obtained during gestation and amniotic fluid and secretions (AF-S) obtained from the infants' mouths at delivery were tested for ability to neutralize HS. AF or AF-S were incubated with an equal volume of virus inoculum for 1 hr at 37°C. Neutralization of virus was assessed by reduction in expected plaque forming units (pfu). Maternal serum antibody was considered absent if the neutralization titer was <1:5, low if 1:5-1:39, and high if ≥1:40. AF and AF-S from 22 women whose serum titers were <1:5 did not neutralize HS. Ninety-six percent of AF or AF-S from 32 women with high serum antibody neutralized 50 pfu/0.lcc and 83% neutralized 500 pfu/0.1cc. Among women with low serum antibody, 52% of samples neutralized 50 pfu/0.1cc and 31% neutralized 500 pfu/0.1cc. Treatment with protein A to remove IgG also removed the neutralizing activity. Antibody to HS is, therefore, present in AF and the quantity present correlates with the mother's serum antibody titer. These results are consistent with a decreased risk of infection in infants of mothers with high antibody titers.
Rootstock influence over 25 years on yield, yield efficiency and tree growth of cultivars ‘delicious’ and ‘golden delicious’ apple (Malus domestica Borkh.)

Abstract The influence of nine rootstocks on growth and production of cultivars ‘Goldspur’ (GS) and ‘Wellspur Delicious’ (WS) and of three rootstocks on growth and production of cultivars ‘Red King Delicious’ (RK) and ‘Golden Delicious’ (GD) apple was evaluated. With spurred scions (WS and GS), the largest trees were on seedling (sdlg), Malling Merton (MM) 104 and MM 109 roots, and the smallest were on Malling (M) 26. Annual yields of most combinations had reached a plateau but none showed significant signs of decline after 25 years. WS cumulative yields were not significantly greater than RK (non-spur). GD produced greater cumulative yields than GS. When cumulative yields among nine stocks within spurred scions were compared, GS/MM 106 and MM 104 and WS/MM 109 and MM 106 ranked highest. Yield efficiencies were superior with M 26, spurred growth habit and clonal stocks.
Mesoscale Associations Between Midwest Land Surface Properties and Convective Cloud Development in the Warm Season

The study of land surface-atmosphere interactions is vital to understanding climatic variations in the Earth's planetary boundary layer, particularly given continual land cover modifications by hum...
Watermass Properties of the Antarctic Slope Front: A Simple Model*

Abstract In the Antarctic, dense shelf water is formed in coastal polynyas and is differentiated from the fresher surface water by the wind-induced ice motion that displaces offshore the ice melt from production zones. Where the shelf water discharges into the deep ocean, the Antarctic Slope Front (ASF) is V shaped, separating the shelf and surface waters (referred to as “frontal” waters) from the Circumpolar Deep Water (CDW). To elucidate basic constraints on frontal properties, a minimal model of homogeneous water masses forced by offshore wind and freshwater input in a perpetual winter is considered. With the surface water stirred by—and hence aligned with—the ice cover, there is little leakage of ice or meltwater from the frontal system, so ice production and melt merely redistribute heat and salt between frontal waters. As such, the heat loss to the atmosphere needs to be supplied by entraining CDW, which then necessitates the shelf water discharge on account of the mass balance. Because of the fresh...
Do Terrorist Attacks Increase Closer to Elections

The shadow of violence that elections cast remains poorly understood. A key obstacle impeding cross-national empirical analysis of electoral violence has been the varied nature of such violence. To address this challenge, I examine terrorist attacks as one particular form of electoral violence. By tracking the incidence of terrorist violence relative to election dates over time and across countries using an original dataset for the period from 2000–2005, I find strong support for the hypothesis that terrorist violence increases as we move closer to an election date. In fact, terrorist violence approximates a normal distribution centered on the election date.
Cardiovascular effects of breathing 95 percent oxygen in children with congenital heart disease

The hemodynamic effects of breathing 95% oxygen were evaluated in 26 children with congenital heart disease. Aortic, pulmonary arterial, right atrial, and pulmonary arterial wedge pressure, aortic and pulmonary artery oxygen saturation, and blood gas, cardiac index, and heart rate were measured in room air and after each patient had breathed 95 % oxygen for 10 (n = 26) and 20 (n = 5) minutes. Measurements were repeated with the patient again breathing room air for 10 (n = 11) and 20 (n = 6) minutes. After 10 minutes of 95% oxygen, arterial partial pressure of oxygen increased from 85 ± 13 to 420 ± 89 torr (p < 0.001). Aortic mean pressure increased from 80 ± 10 to 83 ± 10 mm Hg (p < 0.01), and systemic vascular resistance increased from 20 ± 7 to 26 ± 8 U (p < 0.001). The cardiac index decreased by 21 % from 3.96 ± 0.94 to 3.12 ± 0.74 liters/min/m2 (p < 0.001) and the stroke index decreased by 11% (p < 0.001). A 23% decrease in oxygen consumption (p < 0.001) was observed, and oxygen transport decreased from 763 ± 179 to 600 ± 161 ml O2/min/m2 (p < 0.001). Cardiac index, stroke index, and systemic vascular resistance did not return to normal until 20 minutes after cessation of oxygen breathing. To determine whether reflex bradycardia is responsible for these oxygen-induced hemodynamic changes, heart rate was kept constant by atrial pacing in a second group of 5 patients. In these children, significant decreases in cardiac index, stroke index, and oxygen consumption, and increases in systemic vascular resistance also occurred with 95% oxygen. Thus, in children with acyanotic congenital heart disease, hyperoxia increases aortic pressure and systemic vascular resistance and decreases cardiac index, stroke index, oxygen consumption, and oxygen transport.
SFG studies on interactions between antimicrobial peptides and supported lipid bilayers

The mode of action of antimicrobial peptides (AMPs) in disrupting cell membrane bilayers is of fundamental importance in understanding the efficiency of different AMPs, which is crucial to design antibiotics with improved properties. Recent developments in the field of sum frequency generation (SFG) vibrational spectroscopy have made it a powerful and unique biophysical technique in investigating the interactions between AMPs and a single substrate supported planar lipid bilayer. We will review some of the recent progress in applying SFG to study membrane lipid bilayers and discuss how SFG can provide novel information such as real-time bilayer structure change and AMP orientation during AMP-lipid bilayer interactions in a very biologically relevant manner. Several examples of applying SFG to monitor such interactions between AMPs and a dipalmitoyl phosphatidylglycerol (DPPG) bilayer are presented. Different modes of actions are observed for melittin, tachyplesin I, d-magainin 2, MSI-843, and a synthetic antibacterial oligomer, demonstrating that SFG is very effective in the study of AMPs and AMP-lipid bilayer interactions.
Heuristic Generation of Layouts (HeGeL): Based on a Paradigm for Problem Structuring

Based on protocol analysis of the designers solving spatial problems in architecture, a paradigm for the designers' behavior was proposed in terms of: problem (re)Structuring, when problem parameters are established or transformed, and problem solving, when these parameters are satisfied in a design solution. In order to calibrate and verify the paradigm, a computer-based system called HeGeL (Heuristic Generation of Layouts) was implemented. The development of HeGeL, its architecture and performance are all described. Implemented as a production system, the computer program simulates behavior of the designers observed in the protocol experiments conducted earlier. This paper is intended to serve multiple purposes. First, architecture of HeGeL is described in terms of representations and operations used, and flow of actions. Based on performance of HeGeL, the validity of the proposed paradigm for the designers' behavior and adequacy of the methodology is discussed. Some research issues that need further ex...
Flashback in Prevaporizing/Premixing Combustion Systems

Upstream flame propagation in prevaporizing/premixing continuous combustors was examined. Simplified axisymmetric burners used in this investigation were selected to simulate the same fundamental combustion processes in practical hardware. Straight cylindrical premixing tubes were used to reduce the possibility of upstream flame propagation mechanisms not associated with classical flashback. Combustor pressure oscillations were monitored and indicated that no flashback occurred due to these oscillations. Propane was selected as the test fuel because of its rapid vaporization characteristics.A characteristic time approach was used to analyze the data because the flashback process can be viewed as a competition between a fluid mechanic time and a chemical reaction time. Use of this technique revealed that stoichiometric contours existed in the premixing tubes of this system at most overall equivalence ratios tested, since the flashback limit was observed to be independent of overall stoichiometry.© 1983 ASME
Effect of particulates and fiber reinforcements on the curing behavior of unsaturated polyester resin

The effect of particulates and reinforcement on the curing behavior of unsaturated polyester resin was investigated. Also investigated was the effect of surface treatment of particulates on the curing behavior of unsaturated polyester resin. We have found that (1) an increase in the surface area, by either increasing the loading of particulates for a fixed particle size or decreasing the size of particulates for a fixed loading of particulates, enhanced the rate of cure, and (2) the treatment of glass beads with γ-methacryloxy propyltrimethoxy silane enhanced the rate of cure of unsaturated polyester resin.
The evolution and status of requirements for ocean data products from the Joint Polar Satellite System (JPSS)

The Joint Polar Satellite System (JPSS) is a successor to the former National Polar-orbiting Operational Environmental Satellite System acquisition program and is responsible for fulfilling civil sector operational requirements for Earth observations applicable to polar-orbiting satellite systems. As the sponsor of the JPSS acquisition, the National Oceanic and Atmospheric Administration (NOAA) is establishing system-level requirements for the sensor and environmental data products, including ocean data products, which will be produced and delivered by the system. Most of the requirements represent an evolution from those driving the acquisition of the predecessor program but there are some important differences, particularly for ocean products associated with normalized water-leaving radiances. Through agreements between NOAA and the Japan Aerospace Exploration Agency, the JPSS requirements accommodate ground system processing and delivery of ocean products that will be available from the Advanced Microwave Scanning Radiometer-2 instrument on the planned Global Change Observation Mission - Water. The requirements also include the processing and delivery of ocean data products from the Microwave Imager-Sounder instrument expected to be manifested as part of the Defense Weather Satellite System.
Algebraic Java classes for numerical optimization

Our software, Jest, comprises a general and extendible library for numerical optimization for science and engineering, Jam, and a particular extension of that framework for seismic image processing, Jag. Jest successfully separates optimization and application software without imposing limitations on an application's vector representation, on an application's operator implementation, or on a solver's ability to manipulate vectors and operators. To ensure the compatibility of solver and application, Jest includes a set of simple interfaces that define method invocations for the fundamental mathematical objects of numerical optimization, such as vectors, vector spaces, operators, and solvers. Jest's solvers are implemented in terms of these mathematical objects and consequently possess the generality of the original abstract mathematical algorithm. Jest's seismic imaging library, Jag, demonstrates that Jest incurs no restrictions and little or no programming overhead for scientific or engineering software packages. While generally implemented in Java, Jest links some computationally intensive applications to C-routines to improve performance. Once Jest is integrated in our laboratory's electronic book, our research becomes reproducible by the push of a button in any World Wide Web browser. © 1998 John Wiley & Sons, Ltd.
Role of measurement in determining science and technology policy

The United States clearly needs an explicit policy toward research and development for high technology products and manufacturing processes. Gomory & Schmitt (1988) and Cohen & Zysman (1988) present qualitative arguments that this is so. Our research into the technology of semiconductors, computers, and telecommunication equipment (Norsworthy and Jang, 1992) provides concrete quantitative evidence as well. The costs of research and development and early manufacturing experience coupled with the nearly costless diffusion of the results of these activities, create special economic circumstances in most high technology industries. These circumstances are more complex than economies of scale, but equally powerful in their implications for market behavior. Like economies of scale, these circumstances will favor those organizations and countries whose competitive strategies acknowledge their existence, and most successfully exploit their effects. They involve aspects not only of scale economies, but of public goods, learning curves, the time value of information, and the after tax cost of capital. In this essay we attempt to describe the phenomena and illustrate them by reference to the semiconductor and related industries. It is generally understood that the benefits of research are difficult to capture by the company or industry that undertakes the research; the more basic the research, the more difficult it will generally be for the sponsoring agency to capture its benefits. Therefore, profit-seeking enterprises under conditions of competition will generally undertake less research than would be optimal from the point of view of society as a whole. A number of studies, confirm this general proposition (Griliches, 1987; Mansfield et al., 1982). Their estimates of the overall rate of return to R&D to the whole society is far above the return to private investment in general. These facts have been recognized in federal government policies that encourage research through the National Science Foundation, the National Institutes of Health, the R&D tax credit, and so forth.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
WE‐D‐L100J‐06: Ultrasonic Scatterer Size Estimations in Liver Tumor Differentiation

Purpose: To evaluate the utility of an ultrasoundscatterer size estimation method (combined with B‐mode features) to differentiate liver hemangioma (benign) from malignant liver tumors in a clinical study. Method and Materials:Scatterer size is estimated from the frequency dependence of the backscatter coefficient, obtained using a reference phantom method. A tissue mimicking phantom containing glass beads randomly distributed in gel was scanned by a Siemens Antares scanner equipped with a linear array transducer to verify the scatterer size data reduction methodology prior to use in clinical determinations. Excised normal human livertissues and in vivoliver hemangiomas and malignant tumors were evaluated using the methodology using either the Siemens Antares or GE Logic 9 scanners. The results were correlated with biopsy findings. Results: For power spectra estimation, Welch's average approach yields better results than a periodogram and an autoregressive approach. Averaging over 15 independent samples with a gating window length of around 10 wavelengths is desirable to obtain reasonable size estimates based on the trade off between spatial resolution and signal‐to‐noise ratio. Therefore, angular or elevational compounding was used for in vivo data acquisition. A liver hemanigomas exhibited larger effective scatterer sizes than surrounding normal livertissues. Combining B‐mode features, such as a halo sign, with scatterer size estimates may be useful to confirm the benign or malignant classification. Conclusion:Ultrasoundscatterer sizes estimated from frequency dependent backscatter properties may provide useful clinical information, not readily available in conventional ultrasound B‐mode images. Preliminary in vivo results suggest that it may be an effective processing method for distinguishing liver hemangiomas.
Private record matching using differential privacy

Private matching between datasets owned by distinct parties is a challenging problem with several applications. Private matching allows two parties to identify the records that are close to each other according to some distance functions, such that no additional information other than the join result is disclosed to any party. Private matching can be solved securely and accurately using secure multi-party computation (SMC) techniques, but such an approach is prohibitively expensive in practice. Previous work proposed the release of sanitized versions of the sensitive datasets which allows blocking, i.e., filtering out sub-sets of records that cannot be part of the join result. This way, SMC is applied only to a small fraction of record pairs, reducing the matching cost to acceptable levels. The blocking step is essential for the privacy, accuracy and efficiency of matching. However, the state-of-the-art focuses on sanitization based on k-anonymity, which does not provide sufficient privacy. We propose an alternative design centered on differential privacy, a novel paradigm that provides strong privacy guarantees. The realization of the new model presents difficult challenges, such as the evaluation of distance-based matching conditions with the help of only a statistical queries interface. Specialized versions of data indexing structures (e.g., kd-trees) also need to be devised, in order to comply with differential privacy. Experiments conducted on the real-world Census-income dataset show that, although our methods provide strong privacy, their effectiveness in reducing matching cost is not far from that of k-anonymity based counterparts.
Cylindrical void in a rigid-ideally plastic single crystal III: Hexagonal close-packed crystal

The analytical solution is derived for the plane strain stress field around a cylindrical void in a hexagonal close-packed single crystal with three in-plane slip systems oriented at the angle π/3 with respect to one another. The critical resolved shear stress on each slip system is assumed to be equal. The crystal is loaded by both internal pressure and a far-field equibiaxial compressive stress. The deformation field takes the form of angular sectors, called slip sectors, within which only one slip system is active; the boundaries between different sectors are radial lines. The stress fields are derived by enforcing equilibrium and a rigid, ideally plastic constitutive relationship, in the spirit of anisotropic slip line theory. The results show that each slip sector is divided into smaller regions denoted as stress sectors and the stress state valid within each stress sector is derived. It is shown that stresses are unique and are continuous within stress sectors and across stress sector boundaries, but the gradient of stresses is not continuous across the boundaries between stress sectors. The solution shows self-similarity in that the stresses over the entire domain can be determined from the stresses within a small region adjacent to the void by invoking certain scaling and symmetry properties. In addition, the stress state exhibits periodicity along logarithmic spirals which emanate from the void. The results predict that the mean value of in-plane pressure required to activate plastic deformation around a void in a single crystal can be higher than that necessary for a void in an isotropic material and is sensitive to the orientation of the slip systems relative to the void.
Serotonin involvement in cocaine sensitization: Clues from studies with cocaine analogs

While the behavioral effects of cocaine are generally ascribed to its ability to inhibit the uptake of dopamine, there is evidence to indicate that some of the other pharmacological properties of cocaine may play a significant role in its actions. Behavioral, biochemical, and electrophysiological data suggest that the potent inhibition of serotonin uptake elicited by cocaine is a mechanism that may contribute to its overall effects in vivo. Cocaethylene is the ethyl ester of benzoylecognine which is formed in vivo during concurrent ingestion of cocaine and ethanol. Cocaethylene is equipotent with cocaine as an inhibitor of dopamine uptake, but less potent as an inhibitor of serotonin uptake. We have compared the effects of acute and chronic cocaine and cocaethylene on rat locomotor activity in an attempt to determine the serotonin component in this behavior. Acute dose-response studies revealed that at higher doses (20 mg/kg ip) cocaethylene produced less stimulation of locomotor activity than cocaine. Prior exposure to cocaine resulted in an augmented response to a subsequent challenge dose of either cocaine (sensitization) or cocaethylene (cross-sensitization). However, previous treatment with cocaethylene did not significantly affect the locomotor activity produced by challenges with cocaethylene or cocaine. The involvement of serotonergic systems in the development of cocaine-induced sensitization is one intriguing possible explanation of these data. Biochemical studies have shown that other cocaine analogs possess even more selectivity for the dopamine uptake site than cocaethylene. In terms of comparative potency as inhibitors of dopamine, serotonin, and norepinephrine uptake, isopropylcocaine (isopropyl ester of benzoylecognine) is more selective than even cocaethylene. A metabolically resistant analog of cocaine, β-CIT (2β-carbomethoxy-3β-(4-iodophenyl)tropane), was shown to be extraordinarily long-acting, stimulating locomotor activity for 10 h following a dose of 0.1 mg/kg ip. Furthermore, β-CIT was extremely potent, inhibiting dopamine or serotonin uptake in vitro at a concentration 100 times lower than is required for cocaine. Thus, isopropyl or other substitutions at the carbomethoxy position of the cocaine or β-CIT structures may provide useful tools for the analysis of the serotonin or norepinephrine components in cocaine's actions and as selective probes of central dopamine systems in imaging studies. © 1993 wiley-Liss, Inc.
Is the amount of death instinct constant among U.S. Indian health service areas: A replication

Death rates for nonmotor vehicle related accidents, heart disease, and murder were obtained from the U.S. Indian Health Service for all 11 health service areas. In contrast to predictions derived from Tabachnick and Klugman's hypothesis that the amount of death instinct per capita in different regions should be constant, no statistically significant negative correlations were found for these three variables. These findings replicate results from earlier studies using Native and non-Native American populations.
Exploring the Role of “Global Mindset” in Leading Change in International Contexts

In this article we introduce “global mindset” as an individual-level variable to help explain the effectiveness of managers leading change in international contexts. We describe and analyze an organization change effort at Johnson & Johnson Consumer Products Brazil with a focus on the degree to which the change leader possessed the intellectual, psychological, and social capitals that compose a global mindset. This is an exploratory analysis intended to help map out the key characteristics of managers associated with effectively leading change in cross-culturally complex situations.
Stability of Protease Q against Autolysis and in Sodium Dodecyl Sulfate and Urea Solutions

Protease Q, a recently discovered subtilisin-like protease, exhibited unusual stability in 10% sodium dodecyl sulfate (SDS) and 8 M urea solutions. In 2% SDS it exhibited higher activity than the control, and in 10% SDS it retained 50% of its original activity when azocoll was used as substrate. Kinetic studies showed that the decrease in the activity of protease Q in SDS solutions followed a first order kinetics with a half-life of 446, 278, 78, and 24 h in 1%, 2%, 5%, and 10% SDS, respectively, at 25 degrees C. Protease Q was also stable against autolysis. In 20 mM Tris-HCl buffer (pH 8.3) containing 1.0 mM CaCl2, protease Q had a half life of 2822 h and 725 h at room temperature and at 37 degrees C, respectively. The enzyme was able to completely hydrolyze beta-lactoglobulin, beta-casein, and keratin in 8-10 M urea.
Evaluation of Nine Teat Dip Formulation Under Experimental Challenge to Staphylococcus Aureus and Streptococcus Agalactiae

Abstract Nine postmilking teat dips were evaluated by an experimental challenge model against either Staphylococcus aureus, Streptococcus agalactiae , or both. Formulations containing .9 and .6% sodium hypochlorite, 1% sodium dichloro-s-triazene-trione, .55% chlorhexidine gluconate, and .35% povidone iodine reduced incidence of Staphylococcus aureus infections 56.8, 28.3, 75.9, 92.5, and 77.9%. Incidence of infections with Streptococcus agalactiae was reduced 48.1 and 63.2% by 1.7 and 1% sodium dichloro-s-triazene-trione formulations. The 1% chlorhexidine gluconate and .35% povidone iodine products reduced Streptococcus agalactiae infections 71.0 and 67.0%. Three experimental 1% iodophor formulations reduced Streptococcus agalactiae infections 28.9, 44.8, and 50.7%. The experimental challenge model was refined further and provided an efficient method to determine efficacy of post-milking teat dips.