cssi/SciSciGPT-SciSciNet huggingface dataset:
Crystallization, optimization and preliminary X-ray characterization of a metal-dependent PI-PLC from Streptomyces antibioticus

A recombinant metal-dependent phosphatidylinositol-specific phospholipase C (PI-PLC) from Streptomyces antibioticus has been crystallized by the hanging-drop method with and without heavy metals. The native crystals belonged to the orthorhombic space group P222, with unit-cell parameters a = 41.26, b = 51.86, c = 154.78 A. The X-ray diffraction results showed significant differences in the crystal quality of samples soaked with heavy atoms. Additionally, drop pinning, which increases the surface area of the drops, was also used to improve crystal growth and quality. The combination of heavy-metal soaks and drop pinning was found to be critical for producing high-quality crystals that diffracted to 1.23 A resolution.
The role of iron in enhancing anaerobic toluene degradation in sulfate-reducing enrichment cultures.

Ferrous iron enhanced the toluene degradation rate of sulfidogenic enrichment cultures inoculated with contaminated subsurface soil from an aviation fuel storage facility near the Patuxent River (Md.). Ferrous iron had an analogous effect on the degradation rate of benzoic acid, a transient metabolite of anaerobic toluene degradation in these cultures, when benzoic acid was used as a sole carbon and energy source. Two hypotheses were proposed to explain iron's effect: (a) Iron may have prevented sulfide toxicity via precipitation of sulfide as FeS, and (b) iron might have been a limiting nutrient required for degradation (i.e., amendments of iron could have compensated for iron removed from solution by precipitation as FeS). To test these hypotheses, substrate degradation rates were compared in the presence of FeSO4 (a sulfate source that both precipitates sulfide species and precludes iron limitation) versus ZnSO4 (a sulfate source that precipitates sulfide species but does not preclude iron limitation) versus MgSO4 (a sulfate source that neither precipitates sulfide nor precludes iron limitation). For both toluene and benzoic acid, FeSO4 and ZnSO4 were comparable in their enhancement of substrate degradation rates and were superior to MgSO4 in that respect. Thus, iron appears to ameliorate sulfide toxicity, not nutritional iron limitation, in these cultures. The observation that ethylenediaminetetraacetic acid, a chelating agent capable of retaining iron in solution in the presence of sulfide, did not stimulate the cultures is consistent with this conclusion. The implications of these results for bioremediation of fuel-contaminated aquifers that contain sulfate-reducing bacteria are discussed.
Neuro-hormonal regulation of sexual receptivity in female Aedes aegypti

Abstract The terminal abdominal ganglion regulates the copulatory behaviour of female Aedes aegypti . Neither the brain, the suboesophageal ganglion, nor the thoracic ganglionic mass appear to be directly involved. Juvenile hormone initiates sexual receptivity by acting directly on the terminal ganglion, on some site closely associated with the terminal ganglion, or on some site which in turn secretes a second humoral factor. Matrone, the male accessory gland pheromone, induces post-insemination refractory behaviour by acting on the same site.
Characteristics of magnetic resonance imaging biomarkers in a natural history study of golden retriever muscular dystrophy

The goal of this study was to assess whether magnetic resonance imaging (MRI) biomarkers can quantify disease progression in golden retriever muscular dystrophy (GRMD) via a natural history study. The proximal pelvic limbs of ten GRMD and eight normal dogs were scanned at 3, 6, and 9-12 months of age. Several MRI imaging and texture analysis biomarkers were quantified in seven muscles. Almost all MRI biomarkers readily distinguished GRMD from control dogs; however, only selected biomarkers tracked with longitudinal disease progression. The biomarkers that performed best were full-length muscle volume and a texture analysis biomarker, termed heterogeneity index. The biceps femoris, semitendinosus and cranial sartorius muscles showed differential progression in GRMD versus control dogs. MRI features in GRMD dogs showed dynamic progression that was most pronounced over the 3- to 6-month period. Volumetric biomarkers and water map values correlated with histopathological features of necrosis/regeneration at 6-months. In conclusion, selected MRI biomarkers (volume and heterogeneity index) in particular muscles (biceps femoris, semitendinosus, and cranial sartorius) adjusted for age effect allow distinction of differential longitudinal progression in GRMD dogs. These biomarkers may be used as surrogate outcome measures in preclinical GRMD trials.
Distribution and reproduction of the southern lantern shark from New Zealand

Distribution, population structure and reproduction are described for the southern lantern shark Etmopterus granulosus at the Chatham Rise, New Zealand. Depth of capture for E. granulosus ranged from 744 to 1420 m, with highest catch rates between 800–1200 m. More than twice as many females as males were captured, and the majority of sharks caught were mature, indicating that there may be segregation according to sex and size class. Only 10 of 492 female sharks captured contained ova in uteri, and none contained embryos. The absence of pregnant females suggests that they move to another area or depth prior to pupping. Size of sharks captured ranged from 20·0 to 78·8 cm total length. Females began to mature at 62 cm total length, and males at 52 cm. There was no evidence of a seasonal reproductive cycle. Ovulation appeared to occur when ova reached a diameter of 40–45 mm. The average number of ova in mature females was 12·7. This information is crucial for assessing the impact of fisheries on E. granulosus populations.
Ideology and Ecological Irrationality

Madness of this magnitude is a uniquely contemporary phenomenon. The capacity to wreak global havoc and the ability to predict that we are going to exercise this demonic capacity in an increasingly destructive fashion are both very recent additions to our cultural repertoire. Scarcely 10 years ago, members of the scientific community could, with only scattered misgivings, believe that our society was pursuing a sane and fruitful course. It was an honest mistake then. Today, that sort of faith can only be the product of perverse selfdeception in the face of painfully discouraging environmental inventories (NAS, 1969), and well-documented indictments of the technological quickfix (Ehrlich and Holdren, 1969). If men of goodwill and understanding are obliged by reason to admit the error of their culture's ways, will not those errors be automatically corrected? Is it not fundamentally impossible for an entire civilization to apply its efforts toward goals it does not want? The burden of this paper shall be to suggest that the most appropriate answer to both these questions is "No." I shall further attempt to show that the very expectation of automatic social regulation and self-correcting policy formation is, in fact, a major contributor to ecological irrationality. It is difficult for those of us steeped in the lore of systems analysis to conceptualize the awesome discrepancies between the acknowledged goals of a society and the actual effects of a society directing its activities toward a realization of those goals as perceived. To gain any understanding of the situation we first must remind ourselves
Jim Rockford or Tony Soprano: Coastal Contrasts in American Suburbia

Both in television shows such as The Rockford Files and The Sopranos and in the fiction of writers such as John Updike, Richard Ford, and Douglas Coupland, popular culture draws a distinction between Atlantic Coast and Pacific Coast suburbs. The differences revolve around two themes. The first concerns the roles of place and space. The second is the varying weight of history, often as manifested through families and social ties. Eastern suburbs and suburbanites are commonly depicted as embedded in place, rooted in time, and entangled in social networks. Western suburbs and suburbanites are often imagined as the opposite—isolated in space, atemporal, and free (or bereft) of social bonds.
Highly magnetostrictive rare earth-iron intermetallic compound for a magnetostrictive laser diode magnetometer

Abstract This paper reports on the construction of a miniature transducer module based on the highly magnetostrictive material Terfenol-D. Its capability of ac field detection at frequencies from 1.5 to 50 kHz is examined. Asymmetric surface mode vibrations of the Terfenol were observed and their impact on the operation of a diode laser sensor is discussed.
Brain region-specificity of palmitic acid-induced abnormalities associated with Alzheimer's disease

Background Alzheimer's disease (AD) is a progressive, neurodegenerative disease mostly affecting the basal forebrain, cortex and hippocampus whereas the cerebellum is relatively spared. The reason behind this region-specific brain damage in AD is not well understood. Here, we report our data suggesting "differential free fatty acid metabolism in the different brain areas" as a potentially important factor in causing the region-specific damage observed in AD brain.
WE-G-217A-05: Automatic Method for RF Coil Assessment in Clinical MRI: A Three-Dimensional Approach.

Purpose:MRI RF coil assessment is usually evaluated with region‐of‐interest (ROI) analysis from a single 2D phantom image. This simple approach has worked well for large volume coils or phased‐array coil with large receivers, but not the high density phased‐array coils characterized by 3D array arrangement of their multiple receivers. This abstract proposes a novel approach for quantitative coil assessment based on 3D imaging and 3D ROI analysis.Methods: To characterize all receivers of the coil of interest, a large uniform phantom (preferably a corresponding anthropometric phantom) and a large 3D geometric coverage fully includes the coil sensitivity volume was applied during MR imaging. After imaging, data from all receivers were used to reconstruct a composite 3D image, and to reconstruct 3D images from each individual receiver, leading to a total of N+1 3D image datasets (where N is the number of coil channels). IDL programs were developed to automatically perform ROI analysis on the composite image and on the individual receiver images. Instead of choosing one single 2D slice out of each 3D dataset, the whole 3D dataset was treated as a 3D image, and 3D ROIs were automatically generated for coil assessment. Results: This 3D coil evaluation approach could be applied to all clinical coils including quadrature body/head coils, and phased‐array coils with 2 to 32 channels. 3D sensitivity map could be generated to check receiver function visually. 3D mean SNR, max SNR, and uniformity could be obtained from composite and individual channel 3D images fully automatically. Coil/receiver performance assessment was very fast and straightforward, regardless of the number of receivers of the coil. Conclusions:3D imaging in combination with 3D automatic ROI analysis is a fast, convenient, and less subjective approach for quantitative coil assessment, particularly for high density phased‐array coils.
Elimination Kinetics of Ethanol in a 5-Week-Old Infant and a Literature Review of Infant Ethanol Pharmacokinetics

Primary ethanol metabolism occurs through alcohol dehydrogenase, but minor metabolic pathways such as the P450 enzymes CYP2E1 and CYP1A2 and the enzyme catalase exist. These enzymes have distinct developmental stages. Elimination kinetics of ethanol in the infant is limited. We report the elimination kinetics of ethanol in a 5-week-old African-American male who had a serum ethanol level of 270 mg/dL on admission. A previously healthy 5-week-old African-American male was brought to the ED with a decreased level of consciousness. His initial blood ethanol level was 270 mg/dL. Serial blood ethanol levels were obtained. The elimination rate of ethanol was calculated to be in a range from 17.1 to 21.2 mg/dL/hr and appeared to follow zero-order elimination kinetics with a . Elimination kinetics for ethanol in the young infant has been reported in only four previously published reports. After reviewing these reports, there appears to be variability in the elimination rates of ethanol in infants. Very young infants may not eliminate ethanol as quickly as previously described. Given that there are different stages of enzyme development in children, caution should be used when generalizing the elimination kinetics in young infants and children.
Structural Insights into the Avian AICAR Transformylase Mechanism

ATIC encompasses both AICAR transformylase and IMP cyclohydrolase activities that are responsible for the catalysis of the penultimate and final steps of the purine de novo synthesis pathway. The formyl transfer reaction catalyzed by the AICAR Tfase domain is substantially more demanding than that catalyzed by the other folate-dependent enzyme of the purine biosynthesis pathway, GAR transformylase. Identification of the AICAR Tfase active site and key catalytic residues is essential to elucidate how the non-nucleophilic AICAR amino group is activated for formyl transfer. Hence, the crystal structure of dimeric avian ATIC was determined as a complex with the AICAR Tfase substrate AICAR, as well as with an IMP cyclohydrolase inhibitor, XMP, to 1.93 A resolution. AICAR is bound at the dimer interface of the transformylase domains and forms an extensive hydrogen bonding network with a multitude of active site residues. The crystal structure suggests that the conformation of the 4-carboxamide of AICAR is poise...
FEEDBACK CONTROL OF A THERMOMECHANICAL INPLANE MICROACTUATOR USING PIEZORESISTIVE DISPLACEMENT SENSING

Feedback control has proven useful in improving reliability and performance for a variety of systems. However there has been limited success implementing feedback control on surface micromachined MEMS devices. The inherent difficulties in sensing microscale phenomena complicate the development of an economical transducer that can accurately monitor the states of a surface micromachined system. We have demonstrated a simple and effective sensing strategy that uses the piezoresistive property of the polysilicon thin film of which surface micromachined MEMS devices are fabricated. The states of the device are monitored by measuring the change in resistance of flexible members which deflect as the device moves. Measurement of the output displacement of an in-plane thermal actuator is presented as a candidate application. While there still is a noise issue to be dealt with, this approach provides adequate signal strength to implement feedback control using off-chip analog circuitry. Implementation of proportional/integral control on the system is successfully demonstrated.Copyright © 2004 by ASME
Channel Estimation and Phase-Correction for Robust Underwater Acoustic Communications

This paper presents a new channel estimation, equalization, and phase correction scheme to combat the convergence and stability problem encountered by time-domain adaptive equalizers in underwater acoustic communication systems. Large Doppler spread and symbol scaling in underwater channels have been challenging problems causing significant phase drift and performance degradation. Our new method targets this problem by first allowing phase errors in the estimation of the fading channel coefficients and then perform group-wise (rather than symbol-wise) phase estimation and correction after equalization and multiple channel combining. Single transmitter and multiple receiver data obtained through ocean experiments have been processed using the proposed method and the results show that the new methods can achieve Bit Error Rate (BER) on the order of 10-4 with very high stability.
Effects of divalent cations on amino acid and divalent cation fluxes in gills of the bivalve mollusc, Mytilus californianus

Effects of the deletion of Ca++, Mg++, or Ca++ and Mg++ on the leakage of primary amines, Ca++, and Mg++ from gills of Mytilus californianus were studied. In the absence of Ca++ the gills leak primary amines and Ca++ for about 30 minutes, after which the primary amines are reabsorbed. In the absence of Mg++ the gills leak primary amines, with no net reabsorption for at least 90 minutes, and show rapid leakage of Mg++. In the absence of both Ca++ and Mg++ amino acid leakage is initially less than in the absence of only one of the cations. Measurements of the kinetics of leakages of Ca++ and Mg++ are consistent with the hypothesis that both ions are associated with the cell surface, but the affinity of Ca++ for the cell surface is greater than that of Mg++. In the absence of Mg++, the influx of 14C-glycine was depressed to about 1/3 that seen in controls, while deletion of Ca++ had no effect on the rate of influx. Increasing the [Mg++] stepwise between 5 × 10−6 and 1 × 10−1 M results in a sigmoidal increase in the rate of influx of 14C-glycine and a hyperbolic increase in the y-intercept of influx curves.
Nitrogen transformations in a range of tropical forest soils

Abstract Nitrogen transformations were measured in soil from 33 sites arranged in 15 classes in five tropical areas. Sites sampled included forests on fertile volcanic and sedimentary soils, infertile oxisols and ultisols, extremely infertile white-sand soils, montane sites, and a primary and a secondary successional sere. In comparison with temperate forests, net N mineralization and nitrification were rapid in intact lowland tropical forests (other than white sands) and microbial 15 N uptake was relatively slow. In contrast, white-sand and upper montane sites had lower rates of mineralization and nitrification and greater microbial immobilization of 15 N; N could be in short supply in many such sites. These patterns of N transformations reinforce inferences about soil N supply based on patterns of litterfall N in tropical forests.
Chlorine Plasma/Copper Reaction in a New Copper Dry Etching Process

The chlorine plasma/copper reaction that is the base of a new copper (Cu) dry etching process was studied. The reaction product is a rough and porous Cu chloride compound film. Influences of process parameters such as plasma exposure time, pressure, plasma power, and substrate temperature, on the copper chlorination process, were explored. In addition to variations of morphology and reaction rate, we also investigated the relationship between the structure of the reaction product and the process condition. The result shows that both the plasma phase chemistry and the ion bombardment energy are critical to the reaction mechanism and the reaction product's morphology. A simple model that describes the progress of the reaction through the Cu layer has been developed based on above results. This study result indicates that it is possible to etch Cu with a plasma process at room temperature. © 2001 The Electrochemical Society. All rights reserved.
Adhesive small bowel obstruction in children: the place and predictors of success for conservative treatment.

The records of 230 adhesive small bowel obstruction (ASBO) episodes in 181 patients have been reviewed to observe the place of conservative treatment and to establish criteria to predict the success of conservative trial. Immediate operation has been reserved for 81 episodes that have presented with fever and leucocytosis and/or localized abdominal tenderness, or complete obstruction. The remaining 149 episodes have initially undergone conservative trial. Although 110 episodes (73.8%) have been cured with conservative trial, 39 (26.2%) subsequently necessitated surgical intervention. No adverse occurrences have been observed during or after delayed operations. There was no strangulated bowel nor mortality both in delayed operation and conservatively treated groups. Recurrence has occurred with rate of 18.75% and 36.47% after surgery and conservative treatment, respectively, being significantly different (P less than .01), but the treatment method of the previous episode has been without influence on the method used in the recurrent obstruction (P less than .05). Among the assumed predictive criteria, age at recent laparotomy (P less than .02), time elapsed between recent laparotomy and obstructive episode (P less than .01), the primary condition necessitating laparotomy (P less than .01), the incision of previous laparotomy (P less than .05), and duration of conservative trial (P less than .01) correlated significantly with the success of conservative trial. The number of previous laparotomies and obstructive episodes (P less than .05) have not showed correlation. By the conservative approach used in selected patients with ASBO, 40% overall have been spared operation, without any adverse occurrences. Using the proposed criteria, the success rate of conservative treatment can be predicted.
Allosteric regulation of CCR5 by guanine nucleotides and HIV-1 envelope.

Abstract The chemokine receptor CCR5 is the principal coreceptor for R5 (macrophage-tropic) strains of HIV-1. CCR5 uses G-proteins as transducing elements. Here we report the biochemical consequences of the interaction between CCR5 and G-proteins. Macrophage inflammatory protein-1β (MIP-1β) binding to CCR5 was potently and specifically inhibited by guanine nucleotides. The molecular mechanism of this inhibitory effect was shown to be a dose-dependent reduction in MIP-1β receptors. We also show that the MIP-1β binding site is allosterically regulated by monovalent cations and that binding of this endogenous agonist is highly temperature sensitive and dependent on divalent cations, characteristic of a G-protein-coupled receptor(GPCR). HIV-1 envelope glycoprotein decreased the affinity of CCR5 for MIP-1β but also altered the kinetics of MIP-1β binding to CCR5, proving that it interacts with a distinct, but allosterically coupled binding site. The findings described herein contribute to our understanding of how CCR5 interacts with chemokines and HIV-1 envelope.
Variation in rates of leaf abscission between plants may affect the distribution patterns of sessile insects

At Sand Lake, Leon County, Florida, mines of Stilbosis quadricustatella, a leaf-mining moth, occur on sand live oak trees (Quercus geminata) over a broad range of densities. Some trees have fewer than 2% of their leaves mined (lightly infested), others up to 70% (heavily infested). Similar levels of infestation are maintained on the same trees year after year. There are no significant negative correlations of miner density per tree with any mortality factor that might explain miner preferences for certain trees. Nor is there a positive correlation with host leaf quality as measured by foliar nitrogen or by total or individual amino acid concentrations of host leaves. Egg-transfer experiments showed that larvae from eggs transferred to lightly infested trees were more likely to be killed by leaf abscission than were those that were transferred to and developed on heavily infested trees. This is the first demonstration that variation in rates of leaf abscission could be an important cause of the observed distribution pattern of sessile insects between conspecific host plants.
PHASE EQUILIBRIUM OF MULTICOMPONENT MIXTURES: CONTINUOUS MIXTURE GIBBS FREE ENERGY MINIMIZATION AND PHASE RULE

Abstract A phase equilibrium computational algorithm based on the minimization of the total Gibbs free energy of the multicomponent continuous system is introduced and the phase rule for a multi-family and multi-phase continuous mixture is formulated. Utilizing this technique it is now possible to perform phase equilibrium computations for mixtures containing both continuous component families and discrete components. Illustrative and comparative examples are introduced by using a continuous mixture equation of state, mixing rules, and combining rules. Comparisons of the experimental phase equilibrium data of a realistic gas-condensate system with the calculated results indicate excellent agreement between the two. The computational time required for the proposed algorithm is substantially reduced from the conventional pseudocomponent techniques.
Polychlorinated dibenzo-p-dioxins and dibenzofurans: Removal from flue gas and distribution in ash/residue of a refuse-derived fuel combustor

Abstract In early 1989, a joint Environment Canada/U.S. Environmental Protection Agency program investigated the effect of changing combustion and flue gas cleaning system variables on the performance of these systems. Using information from earlier characterization tests at the same test site (Mid-Connecticut facility in Hartford), performance data on a refuse-derived fuel combustor and its lime spray dryer absorber/fabric filter (flue gas cleaning) system were obtained under good, intermediate, and poor combustor operation and high, normal, and low sulfur dioxide (SO2) control by the flue gas cleaning system. The independent combustion system variables included steam load, air supply rate, and its distribution. For the flue gas cleaning system, the outlet gas temperature from the spray dryer absorber served as an easily measurable surrogate for the approach to saturation temperature, while SO2 concentration in the flue gas at the fabric filter outlet continuously represented lime stoichiometry. Test data included: acid gas, trace organic, trace metal, and particulate matter concentrations as well as material collection for the determination of ash/residue composition and production rates. In addition, process data and refuse-derived fuel feed and ash/residue generation rates were obtained. Correlations between combustion conditions and furnace emission of organic pollutants are presented. The removal of polychlorinated dibenzo-p-dioxins and dibenzofurans, other organics, and particulate matter from flue gas is reported. The transfer of organics to ash/residue is detailed, and the close relationship between particulate removal and organics removal is noted. The results of input/output analyses of the organics across the flue gas cleaning system are discussed.
Magnetism of MnSi and FeSi

Transition-metal monosilicides MnSi and FeSi show a variety of interesting magnetic and transport properties. They both crystallize in a cubic structure (space group P213) in which magnetic atoms are located at displaced face centered positions. MnSi is a spiral ferromagnet with the Curie temperature Tc at 29K. This fascinating crystal has been extensively investigated by Ishikawa and his colleagues
Convergence of head direction and place information in the CA1 region of hippocampus

The hippocampus has long been considered critical for spatial learning and navigation. Recent theoretical models of the rodent and primate hippocampus consider spatial processing a special case of a more general memory function. These non-spatial theories of hippocampus differ from navigational theories with respect to the role of self-motion representations. The present study presents evidence for a new cell type in the CA1 area of the rat hippocampus that codes for directional heading independent of location information (i.e. the angular component of self-motion). These hippocampal head direction cells are controlled by external and idiothetic cues in a similar way as head direction cells in other brain areas and hippocampal place cells. Convergent head direction information and location information may be an essential component of a neural system that monitors behavioral sequences during navigation. Conflicts between internally generated and external cues have previously been shown to result in new hippocampal place representations, suggesting that head direction information may participate in synaptic interactions when new location codes are formed. Combined hippocampal representations of self-motion and external cues may therefore contribute to path integration as well as spatial memory processing.
Influence of habitat on grouper abundance in the Florida Keys, U.S.A.

There was a significant inshore to offshore pattern in grouper species composition and density on Florida Keys coral reefs. Red grouper Epinephelus morio and black grouper Mycteroperca bonaci were most abundant on inshore patch reefs. Graysby Cephalopholis cruentata was most abundant on offshore reef types. Density among sites ranged from 0 to 0.43, 0 to 0.26 and 0 to 1.23 100 m -2 for red grouper, black grouper, and graysby, respectively. Grouper density exhibited no consistency among sites within similar reef types. The densities of red and black grouper were correlated significantly with either physical or biotic habitat parameters. Graysby were observed in microhabitats with whose benthic features differed significantly from the surrounding habitat. This species was observed in high-relief areas with significantly less octocoral species and colony densities. Larger graysby were observed in areas of higher relief and less octocorals than smaller graysby. Habitat was one of several important factors influencing the distribution of groupers among coral reefs types in the Florida Keys.
Comparison of Experimental and Theoretical Melting Behavior of DNA

High resolution melting curves of total nuclear Dictyostelium discoideum DNA (A×3 strain) are compared to theoretical melting calculated from GENBANK sequences(1.74 % of total) by the statistical thermodynamics program MELTSIM, parameterized for long DNA sequences(1,2). The lower and upper limits of simulated melting agree quantitatively with the experimental melting of total DNA. Calculated melting of coding, intron and flanking regions indicate that intron and flanking DNAs are extremely (A+T)-rich and account for the earliest melting DNA. There is no temperature overlap of these regions with coding DNA. A theoretical denaturation map of DNA containing the ribosomal DNA genes showed excellent agreement with subtransition positions of these genes in experimental curves. Agreement between these calculated and experimental melting data demonstrates our ability to accurately simulate DNA melting in complex eukaryotic genomes. This has important consequences for the understanding of sequence dependent energetic properties of nucleic acids and their potential use as biomaterials.
‘‘IF IT WERE GOD WHO SENT THEM . . .’’: ARISTOTLE AND AL-FĀRĀBĪ ON PROPHETIC VISION

Al-Fārābī’s title of ‘‘Second Teacher’’ after Aristotle is well-warranted. Al-Fārābī’s work serves to illuminate the writings of the ‘‘First Teacher’’ in interesting and overlooked ways that go beyond the parameters of Aristotelian logic. Credence is lent to this assessment through the analysis of a specific topic, namely, authentic prophetic vision. At first glance, this seems like a strange assertion to make given Aristotle’s apparent skepticism and indifference regarding the topic of prophecy. However, as this paper will show, there is a latent theory of prophetic vision in the extant texts of Aristotle that al-Fārābī recognizes and completes in a way that is, in large part, faithful to and consistent with the corpus of Aristotle as we read it today. In the end, al-Fārābī provides insight into how a properly Aristotelian theory of authentic prophetic vision could be realized.
An Effect of Bulk on the Ratio of Fragmentation to Stereomutation in Three Cyclobutane Dimers of 3-Methylenecholest-4-ene

The effect of a large increase in mass and extension of substituents on the thermal rearrangement of a 1,2-divinylcyclobutane system has been investigated by the introduction of two 3-cholest-4-ene units. The ratio of two types of exit channel, fragmentation and stereomutation (Fr/St), from a widely accepted diradical intermediary (caldera) has increased significantly relative to the ratio in a simpler system. We believe this to be the first example of the influence of a ponderal effect on the ratio of two competing processes in a thermal rearrangement. The internal torsional rotations necessary prior to reclosure for the realization of stereomutation have been markedly depressed. One of the three stereoisomeric cyclobutanes reacts substantially more slowly than the other two. In its structure, determined by X-ray diffraction, the two cholestenyl wings are folded closely together within van der Waals radii. The slower reaction may reasonably be ascribed to a relative lowering of heat of formation in this ...
In the dark, out in the cold

For 30% of the population, lack of access to home-energy monitoring devices translates into a lack of power---in more ways than one.
Morphological differentiation of neuropeptide Y neurons in aggregate cultures of dissociated fetal cortical cells: a model system for glia-neuron paracrine interactions

Abstract The temporal changes in the morphological profiles of neuropeptide Y (NPY) neurons and their topographical relationship with glial cells (astrocytes) were characterized in aggregate cultures derived from fetal cortical tissue using immunocytochemical procedures. On day 6 of culture, structures labelled with NPY antibodies were small and uneven in size but many resembled neuronal cell bodies. On day 14, neuronal perikarya were well defined and several morphological types of NPY neurons could be distinguished most of which gave rise to beaded processes: unipolar or multipolar bitufted neurons whose processes branch in close proximity to the cell body; bipolar neurons; and multipolar neurons. On day 23, heavily punctate and asymmetrically labelled cell bodies were dispersed throughout the aggregate; neuronal processes were less conspicuous. At 14 and 23 days, cells expressing glial fibrillary acidic protein (GFAP) and neuronal specific enolase (NSE) were abundantly distributed throughout the aggregate. Using a double immunoreaction on 14-day-old aggregates revealed that GFAP + cells and their processes were in close apposition to and engulfing the NPY neurons. Thus, dissociated fetal NPY neurons undergo morphological differentiation in culture along with astrocytes (GFAP +) and other neuronal cell types (NSE +). Based on the topographical association of astrocytes and neurons, particularly NPY neurons, we propose that the aggregate culture system can serve as a model to study the role of paracrine interactions in the regulation of the expression of NPY.
Design of single and multiple zone junction termination extension structures for SiC power devices

Abstract The design of SiC planar and non-planar junction termination extension (JTE) structures are investigated through calibrated quasi-3D numerical simulation. JTE techniques are optimized with respect to breakdown voltage, area consumption, surface fields, and interface charge. Simulated JTE charge profiles predict near-ideal breakdown values with surface fields less than 60% of their bulk values, and show that the critical implant activation percentage can vary as much as 40% with only 10% reduction in breakdown voltage for lightly doped blocking layers. These results are extended to unique multiple-zone JTE and mesa-JTE structures applicable to a wide range of planar and non-planar SiC power devices.
Structure and properties of filamentous green algae

Abstract The green alga Cladophora glomerata obtained from freshwater rivers in California has been characterized. The structure of the algal fibers has been examined through optical and scanning electron microscopy. The tensile properties of individual algal filaments have been measured. The results indicate that the algal filaments consist of cylindrical cells 40 to 100 μm in diameter and 100 to 400 μm in length. The cell walls are composed of crystalline cellulosic microfibrils and are about 10% of the cell diameter. A variety of foreign algal species may adhere to the growing filament of Cladophora glomerata. The tensile strength of the algal filament is estimated to be between 5 and 35 MPa. The tensile properties may depend on the properties in the season when the algae are harvested. The algal fibers can be used as a filler in a number of composites.
Irrigation Effects on Water Use, and Production of Tap Roots and Starch of Buffalo Gourd

Avec des protocoles d'irrigation, on a montre qu'un stress modere reduisait l'utilisation de l'eau par la plante sans affecter le rendement en amidon, ce qui confirme l'interet de cette espece pour la production d'amidon en regions semi-arides
The moral significance of the genetic relation

Our ordinary moral attitudes give a prominent place to the principle that each person ought specially to care for any child who is his or her genetic offspring. From this principle of genetic-parental responsibility and other plausible premises, we can derive the principle that each person has the right to control the genetic use of his or her own genes. But there are competing principles of parental responsibility that require consideration. Principles of nurture are among the important competitors. Also, the view that a woman has the right to control her own body for reproductive purposes may be based on a principle that denies the genetic-parental principle.
Close Corporation Remedies and the Evolution of the Closely Held Firm

This paper examines the law of closely held firms from an evolutionary perspective. The corporate tax and constraints on the availability of limited liability forced closely held firms to compromise their planning objectives and choose standard forms that did not fully reflect their needs. This forced courts to construct duties and remedies that did not relate to the parties' contracts. The famous close corporation case of Wilkes v. Springside Nursing Home, Inc. classically illustrates this problem. The advent and spread of the limited liability company significantly increased the availability of suitable standard forms for closely held firms. As a result, courts now can focus on fully effectuating the parties’ contracts rather than creating remedies the parties may not have wanted. This analysis has implications for potential improvements in contracting for closely held firms.
Two-voice complexity from a single side of the syrinx in northern mockingbird (Mimus polyglottos) vocalizations

SUMMARY The diverse vocal signals of songbirds are produced by highly coordinated motor patterns of syringeal and respiratory muscles. These muscles control separate sound generators on the right and left side of the duplex vocal organ, the syrinx. Whereas most song is under active neural control, there has been a growing interest in a different class of nonlinear vocalizations consisting of frequency jumps, subharmonics, biphonation and deterministic chaos that are also present in the vocal repertoires of many vertebrates, including many birds. These nonlinear phenomena may not require active neural control, depending instead on the intrinsic nonlinear dynamics of the oscillators housed within each side of the syrinx. This study investigates the occurrence of these phenomena in the vocalizations of intact northern mockingbirds Mimus polyglottos . By monitoring respiratory pressure and airflow on each side of the syrinx, we provide the first analysis of the contribution made by each side of the syrinx to the production of nonlinear phenomena and are able to reliably discriminate two-voice vocalizations from potentially similar appearing, unilaterally produced, nonlinear events. We present the first evidence of syringeal lateralization of nonlinear dynamics during bilaterally produced chaotic calls. The occurrence of unilateral nonlinear events was not consistently correlated with fluctuations in air sac pressure or the rate of syringeal airflow. Our data support previous hypotheses for mechanical and acoustic coupling between the two sides of the syrinx. These results help lay a foundation upon which to understand the communicative functions of nonlinear phenomena.
Work Uncertainty and the Promotion of Professional Women: The Case of Law Firm Partnership

Work uncertainty may affect gender disparities in professionals' upward mobility in organizational hierarchies. Professional work involves three forms of uncertainty â problem variability, strategic indeterminacy and dependence on autonomous actors â that weaken the association between performance and ability, leading organizational decision-makers to weigh gender more heavily in promotion decisions. Strategic indeterminacy also increases the need for trust, so decision-makers feel more comfortable promoting candidates of their own sex. These ideas are explored using data on promotions to partnership in U.S. law firms. Findings show that (1) promotions are less likely to go to women when work involves greater problem variability and strategic indeterminacy; and (2) the negative effect of strategic indeterminacy becomes stronger as the proportion of male partners increases.
Usage of application-specific switching activity for energy minimization of arithmetic units

This paper presents a delay constraint power minimization technique for logic incorporating dual supply voltages. The power is reduced by selecting supply voltage according to switching activity of the subunits. The technique employs energy and delay models of arithmetic units with array structure. The supply voltage is selected to reduce power consumption while maintaining propagation delay constraint. The model characterization is done with Verilog simulation where subunits are designed with Cadence and HSPICE using 0.35/spl mu/m CMOS process. We applied the technique on multiplier of general purpose DSP processors and CORDIC. The results obtained from the proposed method are discussed.
Predicting Costs of Stem-Cell Transplantation

PURPOSE: Few studies have formally evaluated the relationship between costs, baseline patient characteristics, and major complications of stem-cell transplantation. We sought (1) to determine whether obtaining baseline information enabled identification of patients whose treatments would be the most costly and (2) to estimate inpatient costs for managing specific transplantation complications. PATIENTS AND METHODS: We collected inpatient costs and clinical information for 236 consecutive patients undergoing transplantation at a single institution between July 1, 1994, and February 20, 1997. Multivariable linear regression was used to evaluate the associations between baseline patient characteristics and costs of hospitalization for initial transplantation and between clinical events and such costs. RESULTS: The median initial inpatient cost in 1997 dollars was $55,500 for autologous transplantation (range, $28,200 to $148,200) and $105,300 for allogeneic transplantation (range, $32,500 to $338,000). When ...
Controlled timing-error acceptance for low energy IDCT design

In embedded digital signal processing (DSP) systems, quality is set by a signal-to-noise ratio (SNR) floor. Conventional digital design strategies guarantee timing correctness of all operations, which leaves large quality margins in practical systems and sacrifices energy efficiency. This paper presents techniques to significantly improve energy efficiency by shaping the quality-energy tradeoff achievable via Vdd scaling. In an unoptimized design, such scaling leads to rapid loss of quality due to the onset of timing errors. We introduce techniques that modify the behavior of the early and worst timing error offenders to allow for larger Vdd reduction. We demonstrate the effectiveness of the proposed techniques on a 2D-IDCT design. The design was synthesized using a 45nm standard cell library. The experiments show that up to 45% energy savings can be achieved at a cost of 10dB peak signal-to-noise ratio (PSNR). The resulting PSNR remains above 30dB, which is a commonly accepted value for lossy image and video compression. Achieving such energy savings by direct Vdd scaling without the proposed transformations results in a 35dB PSNR loss. The overhead for the needed control logic is less than 3% of the original design.
Gap-phase regeneration in selectively logged lowland swamp forest, northeastern Costa Rica

For sustainable logging to be achieved in tropical forests, there must be successful gap-phase regeneration to restock the logged-over area. This study examined three aspects of gap-phase regeneration in selectively logged lowland swamp forest of northeast Costa Rica. First, logging gaps were censused immedi- ately after extraction to determine the density of advanced regeneration. Stem density and basal area of residual trees '10 cm dbh in logging gaps was >85% lower than undisturbed forest, and all trees in gaps had sustained structural damage. The common canopy species Pentaclethra macroloba (Fabaceae) was the most abundant species in gaps whereas the timber tree Carapa nicaraguensis (Meliaceae) was absent from all censused gaps. This suggests that canopy replace- ment, particularly by Carapa, will depend on trees < 10 cm dbh or by seed input into logging gaps. Second, the diversity of the understorey was compared with 6-y old single-tree and multiple-tree logging gaps. Multiple-tree logging gaps were the most diverse, but dominated by two ruderal species; however many shade-tolerant species were present in those gaps. This indicates that controlled selective logging can result in a localized shift in species composition, but that logging gaps should return to pre-logging composition with time under a carefully implemented, con- trolled harvesting regime. Finally, this study found a significant effect of a fringing Carapa tree on logging gap seedling density. Thus, seed arrival into gaps is a bar- rier to logging gap regeneration, particularly for a large-seeded tree species. Gap- phase regeneration by a large-seeded tree species in managed forest would benefit from seed broadcasting into gaps.
Disciplinary Mosaic: The Case of Canadian Sociology

The absence of any dynamic quality to the Canadian political system could probably in a large measure be attributed to its separation from the world of higher learning. The association of the intellectuals with the bureaucracy of government is clear enough. However expert they may be, or however many insights they may have into the historical processes, however well they might uncover the evolution of Canadian self-government, they remain aloof and objective. The dynamic dialogue so essential to social change and development can come only from scholarly intellectuals. The intellectuals of the mass media world have no disciplined training, and are unlikely to provide the dialogue. Far from contributing to the dialogue, intellectuals of the higher learning have done their best to mute it. John Porter, The Vertical Mosaic (1965)
Injuries and injury prevention among indigenous children and young people

Throughout the world, injuries and violence are a leading cause of mortality and suffering among Indigenous communities. Among American Indian and Alaska Native children aged 1 to 19 years, 71% of deaths are from injuries. Motor-vehicle accidents, attempted suicide, and interpersonal violence are the most common causes of injuries in highly industrialized countries. For Indigenous populations in middle- and low-income countries, trauma caused by motor-vehicle accidents, agricultural injuries, interpersonal violence, child labor, and the ravages of war are priorities for intervention. To be effective, injury-prevention efforts should be based on scientific evidence, be developmentally and culturally appropriate, and draw on the inherent strengths of Indigenous communities.
Hearts and Minds: The Priority of Affective Versus Cognitive Factors in Person Perception

In two experiments, affect-based and cognition-based attitudes towardaperson wereinduced by varyingthesequenceofaffective and cognitive information presented to subjects while holding the content of these communications constant. In Experiment 1, affective and cognitive persuasive appeals were created by means of a similar order manipulation, whereas in Experiment 2, affective and cognitive persuasive appeals were induced through a focus manipulation. Results indicated that affect-based attitudes were most effectively changed by affective persuasive appeals, whether these appeals were produced by an order manipulation or a focus manipulation. Affect-based attitudes also tended to be expressed with greater confidence than cognition-based attitudes.