cssi/SciSciGPT-SciSciNet huggingface dataset:
Immobilization of hydroperoxide lyase from Chlorella

Hydroperoxide lyase (HPLS) isolated from microalgae is an enzyme that oxidatively cleaves 13-hydroperoxy-cis-9-trans-11-octadecadienoic acid to a C 13 oxocarboxylic acid and a small C 5 fragment. Acetone powder extracts from Chlorella pyrenoidosa and C. fusca that contained HPLS were partly purified by chromatography on DEAE-Sepharose CL-6B. Five commercially available gels were evaluated for their ability to immobilize the HPLS preparations by determining their capacity for protein binding and the activity and stability of immobilized HPLS. It was found that Reacti-Gel (6X) and Affi-Gels 10, 15, 102 and 501 could bind 60-90% of the available protein. However, HPLS activity was detected only when the enzyme was immobilized on Am-Gels 10, 15 and 501. The stability of immobilized HPLS during storage at 5°C for several months was determined. Product yields with repeated use of the immobilized preparations were also determined. These measurements demonstrated that Affi-Gel 10 and 501 are the best gels for the immobilization of HPLS. A pH study of HPLS immobilized on Affi-Gel 501 showed that enzymic activity was retained from pH 6 to pH 9, with maximal activity at pH 6.5.
EFFECTS OF AUXIN ON RATES, PERIODICITY, AND OSMOTIC RELATIONS IN EXUDATION

IN EXPERIMENTS in which indole-3-acetic acid was applied to plants which were subsequently decapitated it was observed that bleeding was increased in treated plants. The process of exudation by which water and nutrients move through decapitated plants is not in all respects identical with the process of translocation in intact plants, since transpiration and perhaps other influences of the shoot have been eliminated or greatly reduced. Early experimenters conceived of transpiration and exudation as two forms of one physiological process. This view has in general been accepted and extended in so far as the processes which are responsible for exudation are now also considered to be active in a similar manner, though not directly measurable, in transpiring intact plants. An influence of auxin on exudation, therefore, is of interest in its possible relation to absorption and translocation of water and nutrients in the growth of plants. In this article results of exudation experiments with Pisum and Helianthus are presented. The influences of applied indole-3-acetic acid on rates of bleeding, composition of exudates, and the characteristics of diurnal changes exhibited by the latter species are reported. The experiments were carried out from October, 1936, to October, 1937. EXPERIMENTS WITH PIsuM.Material and methods.-Pisum plants (Alaska 89) were grown in sand kept at suitable moisture content with tap water, or a solution 2 of similar known composition, in a dark room, at 24 to 26 degrees C. A low intensity ruby red light was used during observations. Eight to ten days after germination, when the plants had reached lengths of from 20 to 30 cm., they were decapitated, as specified, just below the upper or lower lateral bud (bud 2 and 1, respectively). Auxin paste, 10 milligrams of indole-3-acetic acid (Merck) dissolved directly in one gram of lanum anhydrous (Merck), was applied to the stems. Care was taken to treat all plants alike, each with about 5 mg. of paste. The same amounts of auxin-free lanolin paste were applied to an equal number of control plants grown in the same vessel. Glass tubes, tapered to fit, were carefully slipped about 3 to 5 mm. over the cut ends. Exudates collecting in these tubes were removed and measured at intervals.
Effects of Cerium and Aluminum in Cerium-Containing Hierarchical HZSM-5 Catalysts for Biomass Upgrading

We report the synthesis of multifunctional, hierarchical, cerium-containing HZSM-5 catalysts with various aluminum and cerium contents using a dry-gel, dual templating method. The catalysts were characterized by X-ray diffraction, N2 physisorption, scanning electron microscopy, diffuse reflectance UV–Visible spectroscopy, diffuse reflectance Fourier transform infrared spectroscopy, Fourier transform Raman spectroscopy, NH3 temperature programmed desorption and X-ray photoelectron spectroscopy. At low theoretical Si:Al ratios (15 and 20), the formation of amorphous silica–alumina materials was observed. However, at higher theoretical Si:Al ratios (30, 40, and 50), crystalline materials were formed. Furthermore, with Si:Al ratios of 50, cerium incorporation as high as 2.2 wt% was obtained using this procedure. To understand the role of aluminum and cerium in the catalyst, the crystalline materials were studied in the catalytic fast pyrolysis of glucose at 600 °C. The catalysts with cerium incorporated showed an increase in the production of oxygenated chemicals as well as CO, compared with their non-cerium containing analogs.
Transport properties of S0.8Se16M0.2 (M = Al, Ag or Cu) system

Abstract The results are presented of a study of the electrical and optical properties of vacuum evaporated amorphous thin films in the S 0.8 Se 16 M 0.2 (M=Al, Ag or Cu) system. The activation energy and the pre-exponential factor which appear in the dc conductivity are found to be higher in case of Cu than in case of Ag and Al. The reflectance and transmission are used to measure the optical gap. The glass S 0.8 Se 16 Cu 0.2 behaves as a quasi intrinsic semiconductor (the electrical activation energy is about half of the optical gap). The electrical activation energy is about one-third of the optical gap for the chalcogenide glasses S 0.8 Se 16 Al 0.2 and S 0.8 Se 16 Ag 0.2 . The variation in the refractive index and the imaginary part of the dielectric constant with photon energy have also been reported. The influence of composition on the investigated parameters is reported.
Experiments and observations of prothonotary warblers indicate a lack of adaptive responses to brood parasitism

It has been suggested that prothonotary warblers, Protonotaria citrea, respond adaptively to brood parasitism by brown-headed cowbirds, Molothrus ater, even though they lack historical habitat and range overlap with cowbirds. I studied behaviours functioning as potential defences against brood parasitism in the prothonotary warbler, a cavity-nesting host species. Opening sizes preferred by prothonotary warblers were not small enough to exclude cowbirds, and warblers were parasitized heavily in nests with larger openings. Male and female prothonotary warblers were always away from their nests before sunrise when cowbirds laid eggs in their nests. Prothonotary warblers infrequently (6% of 560 nests) deserted nests that were parasitized during the egg-laying period, but frequently (56% of 151 nests) deserted nests that were parasitized before a female warbler laid her first egg. Prothonotary warblers also deserted 60–70% of nests where a cowbird egg, warbler egg or die were experimentally added before egg laying. However, the experimental addition of one of these three objects during the egg-laying period did not elicit desertion. The desertion of parasitized nests was not affected by nest site availability as has been reported elsewhere in the literature. This lack of a response to brood parasitism by prothonotary warblers may be an example of evolutionary lag, because it is likely that they have only recently been exposed to widespread parasitism, and they accept parasitism at a high cost to their own reproductive success.  2003 Published by Elsevier Science Ltd on behalf of The Association for the Study of Animal Behaviour.
The legacy of September 11: Shared trauma, therapeutic intimacy, and professional posttraumatic growth.

This article describes the personal and professional experiences of the author as a result of her direct exposure to the World Trade Center Disaster. The author proposes the use of the term shared ...
Managing the network with Merlin

This paper presents the Merlin network management framework. With Merlin, administrators express network policy using programs in a declarative language based on logical predicates and regular expressions. The Merlin compiler automatically partitions these programs into components that can be placed on a variety of devices including switches, middleboxes, and end hosts. It uses a constraint solver and parameterizable heuristics to allocate resources such as paths and bandwidth. To ease the administration of federated networks, Merlin provides mechanisms for delegating management of sub-policies to tenants, along with tools for verifying that delegated sub-policies do not violate global constraints. Overall, Merlin simplifies the task of network administration by providing high-level abstractions for directly specifying network policy.
Host Plant Preference, Consumption, Growth, Development, and Survival of Tyta luctuosa (Lepidoptera: Noctuidae) on Biotypes of Field Bindweed and Hedge Bindweed

Larval feeding preference, consumption, and development were assessed for the imported noctuid moth Tyta luctuosa (Denis & Schiffermuller) on 4 biotypes of field bindweed, Convolvulus arvensis L., and on hedge bindweed, Calystegia sepium L. No preference, either innate or induced, was observed in 4th and 5th instars for any of the plant types tested. The food source of early instars did not significantly affect later instar development. Food plant type also did not significantly affect maximum larval weight or survival of 1st-5th instars. However, prepupal survival was significantly greater on field bindweed biotype 1. Development from the 4th instar to the prepupa was slower on hedge bindweed than on any of the field bindweed biotypes. Delayed development on hedge bindweed may be related to its higher wet/dry weight ratio. Our findings suggest that T. luctuosa may feed nonselectively on mixed biotypes of bindweed in the field. They also indicate that these biotypes would be generally, but not uniformly, suitable for the development and survival of T. luctuosa .
Oncogene alterations in in vitro transformed rat tracheal epithelial cells.

Abstract 10 derivations of rat tracheal epithelial (RTE) cells, including normal cells, normal primary cultures, 7 tumorigenic cell lines and 1 nontumorigenic cell line transformed in vitro by treatment with 7,12-dimethyl-benz[ a ]anthracene (DMBA), benzo[ a ]pyrene (BP) and/or 12- O -tetradecanoylphorbol-13-acetate (TPA) were examined for oncogene alterations. No abnormalities of Ha- ras were seen that were suggestive of amplification, rearrangement or the presence of RFLPs. Analysis of specific-point mutations in Ha- ras using Pst I digestion (codon 12, GGA to GCA) or Ha- ras and Ki- ras using Xba I (codon 61, CAA to CTA) were negative. In one cell line derived by DMBA treatment, changes in the c- myc restriction digest pattern were seen after incubation with Bam HI and Hind III. Northern analysis revealed consistent differences between normal and transformed cells when probed with Ha- ras ; c- myc expression was of low intensity, and the expression of Ki- ras could not be detected. Transfection of RTE cell DNAs into NIH/3T3 cells did not result in the appearance of morphologic transformants. The studies suggest that Ha- ras or Ki- ras codon 61 A to T transversions (CAA to CTA) are not associated with the immoral/tumorigenic phenotype in RTE cells transformed by DMBA or TPA, and are in contrast to results reported in some other biological systems.
The adsorption and reactions of hydrocarbons on Molybdenum single crystal surfaces; when clean and in the presence of co-adsorbed sulfur or carbon

Abstract The chemisorption and reactions of thiophene, 1,3-butadiene, butenes, and n-butane on clean Mo(100), and with sulfur or carbon overlayers, have been investigated using thermal desorption spectroscopy (TDS). The predominant reaction at low additive coverage (0–0.2 monolayers of S or C), and at low ambient pressure (10 -10 Torr) for unsaturated hydrocarbons is decomposition. Butane is the least reactive of the hydrocarbons, and a large fraction (95%) desorbs molecularly at all additive coverages. As additive (S or C) coverage increases the amount of decomposition decreases, enabling other reaction pathways to become more probable. Hydrogenation, partial dehydrogenation, and isomerization reactions are detected. Molecular binding on the additive overlayers was also found to be very different. On sulfur overlayers the binding of the hydrocarbons was weak (physisorption), usually on the order of the heat of sublimation (9–10 kcal/mol). However, molecular binding on carbon overlayers was stronger: the heat of desorption was 17–23 kcal/mol for thiophene and butadiene, 12–15 kcal/mol for the butenes, and 11 kcal/mol for butane. In addition, isomerization of 1-butene to 2-butene, occurred on the carbon overlayer. It is suggested that the metal sites control the reactions observed (except for isomerization). This accounts for the similarity in surface reaction product distributions, and explains why the difference in molecular hydrocarbon binding between the sulfur covered and carbon covered surface plays a minor role in these reactions.
And the Best Picture is — the HIV gp120 envelope, please!

X-ray crystallographic structure of the gp 120 core coupled with mutagenesis analyses reveal details of receptor interactions and multiple layers of immune evasion.
On robustness of the test for detection of multivariate outliers

In this paper, Wilks' [Wilks, S.S., 1963, Multivariate statistical outliers. Sankhya, Ser. A, 25, 407–426.] multivariate normal results for detection of outliers are extended to the multivariate elliptically symmetric case, with mean slippage and dispersion slippage outlier model. The main result can be viewed as a robustness property of Wilks' [Wilks, S.S., 1963, Multivariate statistical outliers. Sankhya, Ser. A., 25, 407–426.] statistic as a likelihood ratio test statistic to detect outliers against non-normal multivariate distributions.
Unusual intramedullary vascular lesion: report of two cases.

Objective and importance Spinal arteriovenous malformations have been divided by location into dural (Type I), intramedullary glomus (Type II), juvenile (Type III), and perimedullary direct arteriovenous fistulae (Type IV). We report two cases of an unusual intramedullary proliferation of hyalinized capillaries that do not fit into any of these categories. Clinical presentation A 27-year-old woman and a 62-year-old man presented with subacute progressive caudal myelopathy. Magnetic resonance imaging revealed focal spinal cord enlargement, high signal on T2-weighted images, and patchy enhancement with gadolinium consistent with tumor. No serpentine flow voids were visualized on the surface of the spinal cord. Spinal angiography revealed nothing abnormal. No abnormal vasculature was grossly visible on open biopsy. Histological examination of the tissue specimens revealed a proliferation of capillary-sized vessels with varying degrees of vascular wall changes ranging from endothelial hyperplasia to concentric hyalinization, suggesting ongoing evolution of the lesion. Surrounding neural tissue demonstrated ischemic changes characterized by myelin and axonal loss and astrocytosis but no necrosis. Intervention Patients were treated with chronic anticoagulation, which seemed to slow, but not halt, symptomatic disease progression. Conclusion Although the pathological substrate seems to be an acquired intramedullary vascular lesion characterized primarily by capillary proliferation, the cause of this lesion is unknown. This disease differs from Foix-Alajouanine syndrome and subacute necrotizing myelopathy by an absence of abnormal surface vessels and a lack of intramedullary necrosis. The histological findings are reminiscent of the process that occurs in the kidney and various end organs from long-standing mild to moderate elevations in blood pressure or chronic diabetes. Tissue ischemia may result from luminal obstruction by severe hyalinization and thrombosis. Because the natural history of this disease is unknown, it is unclear whether anticoagulation slowed disease progression.
Development, validation, and results of a survey to measure understanding of cardiopulmonary resuscitation choices among ICU patients and their surrogate decision makers

Shared-decision-making about resuscitation goals of care for intensive care unit (ICU) patients depends on a basic understanding of cardiopulmonary resuscitation (CPR). Our objective was to develop and validate a survey to assess comprehension of CPR among ICU patients and surrogate decision-makers. We developed a 12-item verbally-administered survey incorporating input from patients, clinicians, and expert focus groups. We administered the survey to 32 ICU patients and 37 surrogates, as well as to 20 resident physicians to test discriminative validity. Median (interquartile range) total knowledge scores were 7 (5-10) for patients, 9 (7-12) for surrogates, and 14.5 (14-15) for physicians (p <.001). Forty-four percent of patients and 24% of surrogates could not explain the purpose of CPR. Eighty-eight percent of patients and 73% of surrogates could not name chest compressions and breathing assistance as two components of CPR in the hospital. Forty-one percent of patients and 24% of surrogates could not name a single possible complication of CPR. Forty-three percent of participants could not specify that CPR would be performed with a full code order and 25% of participants could not specify that CPR would not be performed with a do-not-resuscitate order. Internal consistency (Cronbach’s alpha = 0.97) and test-retest reliability (Pearson correlation = 0.96, p < .001) were high. This easily administered survey, developed to measure knowledge of CPR and resuscitation preference options among ICU patients and surrogates, showed strong face validity, content validity, internal consistency, test-retest reliability, and discriminative validity. A substantial proportion of ICU patients and surrogates decision-makers have poor knowledge of CPR and basic resuscitation options.
Mechanism of the serum thyroid hormone lowering effect of perfluoro‐n‐decanoic acid (PFDA) in rats

The mechanism and consequences of the serum thyroid hormone lowering effect of perfluorodecanoic acid (PFDA) were examined. Thyroid and pituitary gland functions in PFDA‐treated rats were assessed by measuring radioiodine uptake from the circulation and the ability of the thyroid gland to secrete thyroxine (T4) and triiodothyronine (T3) in response to thyrotropin‐releasing hormone (TRH) stimulation. Serum levels of reverse triiodothyronine (rT3) were measured to test for possible conversion of T4 to a biologically inactive product and the displacement of radiolabeled T4 from rat albumin in vitro by PFDA was examined. Finally, changes in activity of the thyroid hormone‐sensitive liver enzymes glycerophosphate dehydrogenase (CPD) and malic enzyme (ME) in response to PFDA were analyzed. Functional activities of the thyroid and/or pituitary glands appear to be somewhat depressed by PFDA treatment. There was no increased conversion of T4 to rT3. PFDA displaced radiolabeled T4 from rat albumin with an affinity ...
Gastrulation: Wnts Signal Constriction

Recent work shows that Wnt signaling directly regulates the apical constriction that drives gastrulation movements in Caenorhabditis elegans, and also promotes invagination in sea urchins, providing a novel and possibly conserved mode of developmental regulation.
Wiggins interpersonal adjective scales : a dimensional view

Abstract The Wiggins 2-dimensional circumplex is defined by eight scale scores of the Interpersonal Adjective Scales—Revised (IAS-R). The study hypothesis was that 4 biporal factors can account for the correlations among the 64 adjectives of the IAS-R. On the basis of the Cattell scree test, 5 principal components were extracted from the intercorrelations. Following a direct oblimin rotation, the rotated factors were interpreted as Agreeable-Cold-hearted, Extraverted-Introverted, Calculating-Ingenuous. Dominant-Submissive, and Shy. Thus, 4 of the hypothesized factors were confirmed. The findings suggest that a dimensional conception and the interpersonal circumplex are complementary approaches to understanding the interpersonal behavior domain.
Configurational Entropy Approach to the Kinetics of Glasses.

A kinetic theory of glasses is developed using equilibrium theory as a foundation. After establishing basic criteria for glass formation and the capability of the equilibrium entropy theory to describe the equilibrium aspects of glass formation, a minimal model for the glass kinetics is proposed. Our kinetic model is based on a trapping description of particle motion in which escapes from deep wells provide the rate-determining steps for motion. The formula derived for the zero frequency viscosity η (0,T) is log η (0,T) = B - AF(T)kT where F is the free energy and T the temperature. Contrast this to the Vogel-Fulcher law log η (0,T) = B + A/(T - Tc). A notable feature of our description is that even though the location of the equilibrium second-order transition in temperature-pressure space is given by the break in the entropy or volume curves the viscosity and its derivative are continuous through the transition. The new expression for η (0,T) has no singularity at a critical temperature Tc as in the Vogel-Fulcher law and the behavior reduces to the Arrhenius form in the glass region. Our formula for η (0,T) is discussed in the context of the concepts of strong and fragile glasses, and the experimentally observed connection of specific heat to relaxation response in a homologous series of polydimethylsiloxane is explained. The frequency and temperature dependencies of the complex viscosity η (ω< T), the diffusion coefficient D(ω< T), and the dielectric response e (ω< T) are also obtained for our kinetic model and found to be consistent with stretched exponential behavior.
Visual Consciousness Revisited Magnocellular and Parvocellular Contributions to Conscious and Nonconscious Vision

Current theoretical approaches to consciousness and vision associate the dorsal cortical pathway, in which magnocellular (M) input is dominant, with nonconscious visual processing and the ventral cortical pathway, in which parvocellular (P) input is dominant, with conscious visual processing. We explored the known differences between M and P contrast-response functions to investigate the roles of these channels in vision. Simulations of contrast-dependent priming revealed that priming effects obtained with unmasked, visible primes were best modeled by equations characteristic of M channel responses, whereas priming effects obtained with masked, invisible primes were best modeled by equations characteristic of P channel responses. In the context of current theoretical approaches to conscious and nonconscious processing, our results indicate a surprisingly significant role of M channels in conscious vision. In a broader discussion of the role of M channels in vision, we propose a neurophysiologically plausi...
Identification of unknown intraocular material after cataract surgery: Evaluation of a potential cause of toxic anterior segment syndrome

PURPOSE: To describe and identify unknown opaque material between the optic of an AR40 intraocular lens (IOL) injected with the Emerald Series implantation system (both AMO, Inc.) and the posterior capsule at the conclusion of routine phacoemulsification to prevent an outbreak of toxic anterior segment syndrome (TASS). SETTING: Ambulatory care center operating room, University of North Carolina Hospitals and Department of Ophthalmology, University of North Carolina School of Medicine at Chapel Hill, Chapel Hill, North Carolina, USA. METHODS: After coaxial phacoemulsification in multiple patients, opaque material was present between the optic of a posterior chamber IOL and the posterior capsule. Although there was no TASS, the material was removed from 2 eyes and analyzed with scanning electron microscopy (SEM) and x-ray microanalysis (XRM). Similarly, crystalline lens, Klenzyme (Steris Corp.), Viscoat (sodium hyaluronate 3.0%-chondroitin sulfate 4.0%), and Provisc (sodium hyaluronate 1.0%) were analyzed. RESULTS: On SEM, the material had an irregular undulating surface similar to that of Provisc. Viscoat and the crystalline lens had smoother surfaces. On XRM, the material contained sodium, chlorine, and calcium, like Viscoat and Provisc, and phosphorous and sulfur, like Viscoat. The material also contained silicone, magnesium, aluminum, titanium, iron, and zinc. Klenzyme had smaller peaks of sodium, chlorine, and calcium and a higher carbon background than the unknown material. CONCLUSIONS: The material was likely ophthalmic viscosurgical device that was chemically and structurally altered by the cleaning and sterilization process. The silicone and metallic elements were probably from the Emerald Series implantation system as the disposable cartridge is coated with silicone and the reusable injector is metal.
Grasshopper (Orthoptera: Acrididae) communities respond to fire, bison grazing and weather in North American tallgrass prairie: a long-term study

Because both intrinsic and extrinsic factors influence insect population dynamics, operating at a range of temporal and spatial scales, it is difficult to assess their contributions. Long-term studies are ideal for assessing the relative contributions of multiple factors to abundance and community dynamics. Using data spanning 25 years, we investigate the contributions of weather at annual and decadal scales, fire return interval, and grazing by bison to understand the dynamics of abundance and community composition in grasshopper assemblages from North American continental grassland. Each of these three primary drivers of grassland ecosystem dynamics affects grasshopper population and community dynamics. Negative feedbacks in abundances, as expected for regulated populations, were observed for all feeding guilds of grasshoppers. Abundance of grasshoppers did not vary in response to frequency of prescribed burns at the site. Among watersheds that varied with respect to controlled spring burns and grazing by bison, species composition of grasshopper assemblages responded significantly to both after 25 years. However, after more than 20 years of fire and grazing treatments, the number of years since the last fire was more important than the managed long-term fire frequency per se. Yearly shifts in species composition (1983-2005), examined using non-metric multidimensional scaling and fourth-corner analysis, were best explained by local weather events occurring early in grasshopper life cycles. Large-scale patterns were represented by the Palmer Drought Severity Index and the North Atlantic Oscillation (NAO). The NAO was significantly correlated with annual mean frequencies of grasshoppers, especially for forb- and mixed-feeding species. Primary grassland drivers-fire, grazing and weather-contributing both intrinsic and extrinsic influences modulate long-term fluctuations in grasshopper abundances and community taxonomic composition.
Torsion freeness of symmetric powers of ideals

Let I be an ideal in a Noetherian commutative ring R with unit, let k > 2 be an integer, and let αk i S k I → I k be the canonical surjective R-module homomorphism from the kth symmetric power of I to the kth power of I. When pd R I < 1 or when I is a perfect Gorenstein ideal of grade 3, we provide a necessary and sufficient condition for αk to be an isomorphism in terms of upper bounds for the minimal number of generators of the localisations of I. When I = m is a maximal ideal of R we show that ακ is an isomorphism if and only if R m is a regular local ring. In all three cases for I our results yield that if α κ is an isomorphism, then at is also an isomorphism for each 1 ≤t≤k.
A simple procedure for approximate factor analysis

A variation of the centroid method is described and illustrated. By the application of new rules for reflecting signs, it may be possible to reduce to insignificance the factor loadings of tests showing insignificant correlation (original or residual) with clusters of tests having relatively high intercorrelations. As a result, a factor common to any one of these clusters may be revealed by the centroid method itself with little or no need for rotation of axes or further calculations.
Cardioprotective effects of monophosphoryl lipid A, a novel endotoxin analogue, in the dog.

Objective: The major objective of the present study was to determine the effects of a new endotoxin analogue, monophosphoryl lipid A (MLA), on myocardial infarct size in dogs. A second aim was to determine if potential cardioprotective effects of MLA might be mediated via an enhancement of antioxidant defence mechanisms. Methods: Barbiturate anaesthetised dogs were subjected to a 60 min left circumflex coronary artery occlusion followed by 5 h reperfusion. Either of two different doses of MLA (30 and 100 μg·kg−1) or an equivalent volume of vehicle were given intravenously 24 h prior to the infarct experiments. Transmural myocardial blood flow was measured at 30 min of occlusion by the radioactive microsphere technique and infarct size was determined at the end of 5 h of reperfusion by triphenyltetrazolium staining. Tissue catalase and myeloperoxidase activities were measured at 5 h of reperfusion as indices of antioxidant activity and neutrophil infiltration, respectively. Results: There were no significant differences between groups in systemic haemodynamic variables, myocardial oxygen demand, ischaemic bed size, or coronary and collateral blood flow to the ischaemic region. However, administration of MLA produced a marked dose dependent reduction in myocardial infarct size: 19.8(SEM 3.7)% and 14.1(2.5)%, respectively, v 32.7(2.9)% in the vehicle control group, p < 0.05. Pretreatment with either 30 or 100 μg·kg−1 of MLA resulted in small increases in tissue catalase activity in the non-ischaemic region of the heart: 0.169(0.033) and 0.197(0.013) K·g−1, respectively, v 0.136(0.013) K·g−1 tissue in the control; however, the increases were not statistically significant by ANOVA. Myeloperoxidase activity in the border zone immediately adjacent to the infarct was markedly decreased in both MLA treated groups: MLA 30 μg·kg−1, 2.69(0.82); MLA 100 μg·kg−l, 2.49(0.47), v control group, 5.81(1.20) units·g−1 tissue; p < 0.05. Conclusions: These data are the first to show a marked cardioprotective effect of a lipid A derivative of endotoxin in an in vivo model of myocardial infarction. Although the mechanism responsible for the reduction in infarct size by MLA is unknown, a reduction in neutrophil migration at the site of ongoing tissue injury, the border zone, may be partially responsible. Cardiovascular Research 1993; 27 :832-838
Angular distribution of alpha particles from the 10B(3He, α)9B reaction☆

Abstract The angular distribution of the ground state alpha particles from the 10 B( 3 He,α) 9 B reaction has been measured at a bombarding energy of 5.50 MeV. A strong backward peak is observed, suggesting significant contributions from a direct exchange mode. The implications of this result on the possible formation of a low lying positive parity state in 9 B are discussed.
Prediction and Measurement of High Quality in Still Image Coding

In image coding applications, quantitative quality metrics which approximate the perceived quality of an image can be used for evaluating the performance of coders, designing new coders and optimizing existing coders. In this paper, we consider images of high quality levels for which most of the errors are in the threshold region of perception, and perceptible errors are sparsely distributed. Two different methodologies are used; first, we use an objective picture quality scale (PQS) which combines partial measures, denoted distortion factors, of random as well as structured perceived distortions due to coding. We also consider an alternative approach, applicable at high quality, that is based on a multi-channel vision model, the visible differences predictor (VDP) proposed by Scott Daly. The VDP produces a probability detection map identifying regions in which errors are sub-threshold, threshold and supra-threshold. For the Phe PQS, since distortion factors due to structured errors and errors in the vicinity of high contrast image transitions are most important at high quality, these two factors are analyzed to compute spatial distortion maps of their contributions. This paper compares the spatial distortion maps produced by both methods for high quality still images to experimental observations. Global values for the quality have been obtained by integrating the factor images obtained using PQS and yield a correlation of 0.9 with mean opinion of score values for JPEG, subband and wavelet coded images.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Estimating of chromophoric dissolved organic matter (CDOM) with in-situ and satellite hyperspectral remote sensing technology

The influence of land surface characteristics and climate conditions on the source, quantity, quality, and timing of dissolved organic carbon (DOC) fluxes to coastal waters is not well understood. The significant correlation between DOC and chromophoric dissolved organic matter (CDOM) leads to an increasing need of CDOM monitoring for understanding the DOC land-water dynamics. This study is to report the results of using hyperspectral in-situ data and satellite images to estimate riverine CDOM from rivers to oceans and Great Lakes. A major research goal is to demonstrate that advancement of hyperspectral and high spatial resolution remote sensing technology is vital to the study of interactive processes between terrestrial ecosystems and aquatic environments. Our research results confirm that hyperspectral remote sensing is effective in extracting riverine CDOM loading.
Learning to See in Irmgard Keun's Das kunstseidene Mädchen

This essay examines Irmgard Keun's novel Das kunstseidene Madchen (1932) against the backdrop of Weimar-era discourses on the emancipatory potential of vision. While the narrative's thematization of vision has been productively analyzed from the perspective of feminist and film theory, less attention has been paid to its ties to contemporary discourses concerned with retooling a vision enhanced by new technologies like film into an instrument of emancipatory self-fashioning. As the article shows, Keun's novel reflects critically on these discourses by casting its heroine's sentimental journey in terms of an education in vision that leads to acknowledging the distance between the visual as a mode of inscription and the visible as a domain of perception. In so doing the novel delivers a critical commentary on contemporary discourses that located agency in a conquest of the visible attained by manipulating the visual.
Intra-Cell Channel Allocation Scheme in IEEE 802.22 Networks

Cognitive radio based IEEE 802.22 wireless regional area networks have been proposed to harness the highly underutilized sub 900 MHz TV bands. In such networks, both base stations and the consumer premise equipments (CPEs) continuously perform spectrum sensing and transmit only on those channels which are not being used by the primary incumbents. In this paper, we propose a heuristic for an efficient channel allocation by a base station to the CPEs in that cell. Due to the lack of dedicated control channels, the BS and CPEs within a cell go through a process of exchanging control messages on free channels. The benefit of such sharing of their mutual spectrum usage helps the base station make informed decisions on the allocation of uplink and downlink channels to CPEs. This, in turn, guarantees no interference to and from the primary licensed incumbents. For validation of the proposed allocation scheme, we conducted simulation experiments. The results show how the proposed scheme ensures allocation to almost all the CPEs in a cell and how the nature of allocation is dependent on the total number of channels scanned, probability of getting a free channel and number of CPEs in the cell.
Mechanistic and response studies of iridium oxide pH sensors

Abstract Results are presented on the pH-potential response of iridium oxide films prepared by d.c. magnetron reactive sputtering. Freshly deposited films exhibit a nearly Nernstian response to pH and little hysteresis. The redox sensitivity of films prepared by sputtering in water-saturated oxygen and annealed in an oxygen atmosphere has been examined as well. In addition, methods are described for preparing model iridium oxide sensor surfaces for ultrahigh vacuum surface analytical studies. Stoichiometric IrO 2 -like surfaces are shown to be relatively inert to gas phase water. Hydroxylation of IrO 2 -like surfaces can be induced, however, by r.f. water plasma treatment.
Occupational Structure and the Employment of American Mothers of Young Children

Explanations for the increase of employment for American mothers with young children have focused on women’s motivations and skills or on increased wages. Instead, this analysis considers how access to professional and managerial occupations may explain this employment trend. Relying on Current Population Survey data (1968–1995), the study reports that growing availability of these occupations explains less than 1/4 of employment growth. The percentage of full-time employed newer mothers in professional and managerial occupations, while having grown substantially over time, remains relatively small. Part-time employment does not explain the trend. Relatively high rates of full-time work, even for low-prestige occupations, affirm existing research emphasizing family economic need and validate questions about the structure of work for accommodating family obligations.
The effects of browse time on the Internet on students’ essay scores

This study examined how 30 minutes of search time on the Web affected students’ essay scores in response to a writing prompt. Expository essays were obtained from 49 fourth- and fifthgrade students enrolled in an elementary school in Virginia, in the United States. Students were placed by random assignment into three groups with the same writing prompt for all three groups. Data analyses using ANOVA indicate that there was statistical significance in two components of writing. The group that received instruction on using the Internet to conduct research in the prewriting phase outperformed the control group in two areas: the total essay score (p=.053) and usage/mechanics (p=.028). The study also produced effect sizes ranging from small to large when the Internet users were compared to the control group. Implications for the future of Internet use in the school system are discussed.
Golgi apparatus buds — vesicles or coated ends of tubules?

Based on cell-free processing whereby membrane glycoproteins from one cell type were processed by enzymes located in Golgi apparatus from another cell type, J. Rothman and colleagues postulated that vesicles budding from one Golgi apparatus stack migrated to and fused with cisternal membranes of other Golgi apparatus stacks in the cell-free milieu. An extension of this hypothesis was that these same or similar vesicles were involved in the trafficking of membrane material from one cisterna to the next even in the same Golgi apparatus stack [W. G. Dunphy, J. E. Rothman: Compartmental organization of the Golgi stack. Cell 42: 13–21 (1985)]. A coated bud revealed by tannic acid-containing fixatives was the morphological entity associated with this intercompartment Golgi apparatus transfer. This report summarizes information from the author's laboratories that suggests that perhaps the majority of these coated buds, while associated with the Golgi apparatus, are not vesicles per se but rather coated ends of tubules. Golgi apparatus tubules have been postulated to permit interconnections among adjacent Golgi apparatus stacks but not to function in transport between contiguous cisternae of the same Golgi apparatus stack.
Experiences with 230 kv on the bonneville system

SOME PAST PRACTICES in the high-voltage transmission of power have been more conservative than proved necessary. Liberalized practices put into effect on the 230-kv system of the Bonneville Power Administration have resulted in sizable annual savings.
Demonstration of a no-moving-parts axial scanning confocal microscope using liquid crystal optics

Abstract For the first time, to the best of authors’ knowledge, a no-moving-parts axial scanning confocal microscope (ASCM) system is designed and demonstrated using a combination of a large diameter liquid crystal (LC) lens and a classical microscope objective lens. By electrically controlling the 5 mm diameter LC lens, the 633 nm wavelength focal spot is moved continuously over a 48 μm range with a measured 3-dB axial resolution of 3.1 μm using a 0.65 numerical aperture (NA) micro-objective lens. The ASCM is successfully used to image an Indium Phosphide (InP) twin square optical waveguide sample with a 10.2 μm waveguide pitch and 2.3 μm height and width. Using fine analog electrical control of the LC lens, a super-fine sub-wavelength axial resolution of 270 nm is demonstrated. The proposed ASCM can be useful in various precision three-dimensional (3D) imaging and profiling applications.
Robust transmit nulling in phased array antennas

The ability to create nulls in the transmit pattern of a phased array antenna has many applications for radar systems, including interference and clutter mitigation. Most nulling techniques introduce small perturbations in amplitude and phase, or phase-only, at each element of the phased array. For practical reasons, phase-only perturbations are desired and they create acceptable rms levels of null depth. However, the phase shift at each element will vary with the frequency of the transmitted signal. As a result, the depth and pointing accuracy of the transmit null will not be uniform over the bandwidth of the transmitted signal. This paper will describe some of the inherent limitations in achieving robust transmit nulling performance over a wide bandwidth when using phase-only, open-loop control on a typical phased array antenna. Some solutions to overcome these limitations and improve the performance of transmit nulls will be proposed.
Chromosome abnormalities in ovarian adenocarcinoma: I. Nonrandom chromosome abnormalities from 244 cases.

Cytogenetics provides important insights into the molecular pathogenesis of human cancers. Although extensive data exist on recurring cytogenetic abnormalities in hematologic cancers, data on individual solid tumor types remain limited. Previous studies of ovarian carcinoma indicated the presence of multiple, complex clonal chromosome abnormalities. Cytogenetics remains one of a few techniques capable of detecting these multiple, simultaneously occurring genetic abnormalities. We describe cytogenetic abnormalities from a series of 244 primary ovarian cancer specimens referred to a single institution. A total of 201/244 cases had fully characterized clonal chromosome abnormalities, of which 134 showed clonal chromosome breakpoints. We used a novel statistical technique to detect nonrandom chromosome breakpoints at the level of chromosome regions. Nonrandom occurrence of chromosome breakpoints was detected at regions 1p1*, 1q1*, 1p2*, 1q2*, 1p3*, 1q3, 3p1*, 1q4*, 6q1*, 6p2, 6q2, 7p1*, 7q1, 7p2*, 11p1*, 11q1, 11q2*, 12p1, 12q2*, 13p1, and 19q1. Simultaneous occurrence of multiple abnormalities was common. However, 120/134 cases had breakpoints at one or more of 13 commonly involved regions (*), suggesting a hierarchy of genetic abnormalities. Among clinical and tumor variables that predict patient survival, tumor grade was significantly associated with the presence of chromosome breakpoints. In additional studies, we show that nonrandom chromosome abnormalities are associated with impaired survival in ovarian cancer and that specific, nonrandomly involved chromosome regions retain significant effects on survival when analyses are controlled for important clinical variables. Additional specific chromosome abnormalities in this series are described, including chromosome gains and losses in near-diploid cases and homogeneously staining regions. These results suggest that recurring, nonrandom chromosome abnormalities are important in the pathogenesis and/or progression of ovarian cancers, and target areas of the genome for molecular genetic studies. Genes Chromosomes Cancer 25:290–300, 1999. © 1999 Wiley-Liss, Inc.
Computer simulations and clear observations do not guarantee conceptual understanding

Abstract Evidence for cognitive benefits of simulated versus physical experiments is unclear. Seventh grade participants (n = 147) reported their understanding of two simple pendulum problems (1) before conducting an experiment, (2) immediately following experimentation, and (3) after a 12-week delay. Problem type was manipulated within subjects – participants' understanding of one problem was typically accurate and for the other was typically inaccurate. Experiments were computer-simulated or hands-on and were observed in a slow motion or real time replay. There was no difference between simulated vs. hands-on or slow motion vs. real time replay for conceptual understanding outcomes. Instead, the problem type, the time of posttest, and the participant's experimentation strategy were significant predictors. Specifically, poor experiments were especially bad at informing understanding of the previously misconceived problem. Furthermore, even for the problem that was previously conceived correctly, accurate understanding declined over twelve weeks for those participants who conducted inadequate experiments. Post hoc tests revealed participants were less likely to control variables during simulations.
Relationship of Processes and Structures of Care in General Surgery to Postoperative Outcomes: A Qualitative Analysis

Background With increased focus on improving surgical care quality, understanding structures and processes that influence surgical care is timely and important, as is more precise specification of these through improved measurement. Study Design We conducted a qualitative study to help design a quantitative survey of structures and processes of surgical care. We audiotaped 44 face-to-face interviews with surgical care leaders and other diverse members of the surgical care team from 6 hospitals (two Veterans Affairs, four private sector). Qualitative interviews were transcribed and analyzed to identify common structures and processes mentioned by interviewees to include on a quantitative survey and to develop a rich description of salient themes on indicators of effective surgical care services and surgical care teams. Results Qualitative analyses of transcripts resulted in detailed descriptions of structures and processes of surgical care services that affected surgical care team performance—and how particular structures led to effective and ineffective processes that impacted quality and outcomes of surgical care. Communication and care coordination were most frequently mentioned as essential to effective surgical care services and teams. Informants also described other influences on surgical quality and outcomes, such as staffing, the role of residents, and team composition and continuity. Conclusions Surgical care team members reinforced the importance of understanding surgical care processes and structures to improve both quality and outcomes of surgical care. The analysis of interviews helped the study team identify potential measures of structures and processes to include in our quantitative survey.