cssi/SciSciGPT-SciSciNet huggingface dataset:
MO-F-211-06: Characterization of Through-Plane Flow Effects on Vascular Input Function Definition and Subsequent DCE-MRI Imaging Biomarkers

Purpose: Quantitative analysis of dynamic contrast‐enhanced (DCE)‐MRI data is becoming increasingly utilized in early phase clinical trials as a means of assessing therapy response. The aim of this study was to characterize the effect of vascular through‐plane blood flow on the quantification of DCE‐MRI data in salivary glands and nodal tumors of the head and neck. Methods: Patients (n=8) were imaged using an axial 3D FSPGR sequence that acquired a frame every 6.4s. Gd‐DTPA was administered (0.1mmol/kg) using a power injector. Pharmacokinetic parameter (Ktrans, kep, vp) maps derived from non‐linear fits of the general kinetic model were calculated using various vascular input functions (VIFs) calculated from pixels selected by an automatic detection algorithm in either an internal jugular vein or carotid artery. Only VIFs for which 90% or more of the vessel's area was selected by the algorithm were considered. One‐way analysis of variance (ANOVA) was performed and coefficients of variation (CVs) calculated for all pixels in each of the submandibular/parotid glands and nodal disease sites for individual patient maps calculated from each VIF. Results: One‐way ANOVA results showed that kinetic parameter VOI averages for all sets of VIFs across axial slices were not equivalent (p≪0.001). CVs ranged from 15% to 70% and 11% to 127% for all kinetic parameters calculated using the jugular vein and carotid artery, respectively. Of the 20 slices, 11 ±2 slices in the imaging volume were above selection threshold for arterial defined VIFs compared with 14±3 slices using a jugular‐derived VIF. Conclusion: Flow effects produced substantially more variation in DCE‐MRI imaging biomarker measures when using arterial input functions to calculate pharmacokinetic parameters as opposed to venous‐derived. Choosing a VIF defined in the jugular vein 2–3 slices below the volume's center provides reproducible results over several slices in this patient population.
Report of the Awards Committee

List the recipients of various 2012 Antennas and Propagation Society awardees and presents a brief professional biography of the recipients.
Interstitial-cell tumor of testicle in children.

Abstract Precocious puberty due to a Leydig-cell testicular tumor associated with an elevated serum testosterone developed in a male dizygotic twin, four years and eleven months old. Orchiectomy resulted in regression of precocious puberty signs and a return of the serum testosterone to prepubertal concentrations.
Steps on anatase TiO2(101)

Surface defects strongly influence the surface chemistry of metal oxides, and a detailed picture of defect structures may help to understand reactivity and overall materials performance in many applications. We report first-principles calculations of step edges, the most common intrinsic defects on surfaces (and probably the predominant ones on nanoparticles). We have determined the structure, energetics, and chemistry of step edges on the (101) surface of TiO2 anatase, an important photocatalytic material. Scanning tunnelling microscopy measurements of step-edge configurations and the contrast in atomically resolved images agree remarkably well with the theoretical predictions. Step-edge formation energies as well as the adsorption energies of water scale with the surface energy of the step facet, a trend that is expected to generally hold for metal oxide surfaces. Depending on the terrace/step configuration, this can lead to a situation where a step is less reactive than the flat terrace.
The pgaABCD Locus of Acinetobacter baumannii Encodes the Production of Poly-β-1-6-N-Acetylglucosamine, Which Is Critical for Biofilm Formation

We found that Acinetobacter baumannii contains a pgaABCD locus that encodes proteins that synthesize cell-associated poly-β-(1-6)-N-acetylglucosamine (PNAG). Both a mutant with an in-frame deletion of the pga locus (S1Δpga) and a transcomplemented strain (S1Δpga-c) of A. baumannii were constructed, and the PNAG production by these strains was compared using an immunoblot assay. Deleting the pga locus resulted in an A. baumannii strain without PNAG, and transcomplementation of the S1Δpga strain with the pgaABCD genes fully restored the wild-type PNAG phenotype. Heterologous expression of the A. baumannii pga locus in Escherichia coli led to synthesis of significant amounts of PNAG, while no polysaccharide was detected in E. coli cells harboring an empty vector. Nuclear magnetic resonance analysis of the extracellular polysaccharide material isolated from A. baumannii confirmed that it was PNAG, but notably only 60% of the glucosamine amino groups were acetylated. PCR analysis indicated that all 30 clinical A. baumannii isolates examined had the pga genes, and immunoblot assays indicated that 14 of the 30 strains strongly produced PNAG, 14 of the strains moderately to weakly produced PNAG, and 2 strains appeared to not produce PNAG. Deletion of the pga locus led to loss of the strong biofilm phenotype, which was restored by complementation. Confocal laser scanning microscopy studies combined with COMSTAT analysis demonstrated that the biovolume, mean thickness, and maximum thickness of 16-h and 48-h-old biofilms formed by wild-type and pga-complemented A. baumannii strains were significantly greater than the biovolume, mean thickness, and maximum thickness of 16-h and 48-h-old biofilms formed by the S1Δpga mutant strain. Biofilm-dependent production of PNAG could be an important virulence factor for this emerging pathogen that has few known virulence factors.
Reaction Pathways in Pentachlorophenol Synthesis. 2. Isothermal Reaction

We performed isothermal pentachlorophenol synthesis experiments to obtain data useful for kinetics analysis and reaction pathway resolution. The rate of pentachlorophenol production was not a monotonic function of temperature, and no pentachlorophenol was ever observed before the tetrachlorophenol yield reached its maximum value. The results were consistent with a reaction network wherein trichlorophenol forms an intermediate product, which then forms tetrachlorophenol. Pentachlorophenol then forms from tetrachlorophenol through an autocatalytic pathway. Microcontaminants produced during pentachlorophenol synthesis included hexachlorobenzene and hexa, hepta, and octachlorodibenzodioxins. The total amount of microcontaminants at a given temperature initially increased with time, and at the higher temperatures reached a maximum and decreased. The total amount of microcontaminants was lower at a lower temperature, for a given pentachlorophenol yield. Finally, these experiments produced pentachlorophenol in r...
Renal cell osteopontin production is stimulated by calcium oxalate monohydrate crystals

Renal cell osteopontin production is stimulated by calcium oxalate monohydrate crystals. Specific anions in tubular fluid, including uropontin (UP), the urinary form of human osteopontin (OPN), block adhesion to renal tubular cells of the most common crystal in kidney stones, calcium oxalate monohydrate (COM). In this study, monkey renal epithelial cells (BSC-1 line) in monolayer culture constitutively secreted UP into the culture medium. COM crystals added to the medium avidly bound previously secreted UP, reducing its concentration by 46% one hour later. However, the net UP content of cultures after a 24-hour exposure to COM crystals was increased by 18%. Northern blotting showed that the constitutively expressed gene encoding human OPN was maximally stimulated in BSC-1 cells after exposure to COM crystals for 12 hours. Two other calcium-containing crystals, hydroxyapatite and brushite, did not alter OPN gene expression or protein production. OPN mRNA expression was enhanced in canine renal epithelial cells (MDCK line) after exposure to COM crystals for six hours, whereas the constitutive expression of murine OPN mRNA by 3T3 fibroblasts was unchanged. In vivo this glycoprotein could defend the cell against adhesion of crystals in tubular fluid, and/or promote renal interstitial fibrosis in subjects with heavy ciystalluria.
Approximate determination of the mass gap in quantum field theory using the method of finite elements

In a previous paper on the method of finite elements we developed an extremely simple procedure for obtaining the approximate energy levels of a quantum-mechanical system. This procedure is purely analytical rather than numerical and it gives accurate results. In this paper we apply this same procedure to self-interacting, two-dimensional, scalar quantum field theory. Specifically, we calculate the mass renormalization for the (${\ensuremath{\varphi}}^{2N}$${)}_{2}$ and the sine-Gordon field theories.
New Biomedical Disciplines and Advances in Computer Performance through Speed Enhancements - Convergence of Problems and Solutions

A class of signal processing problems has been identified which is characterized by input data bandwidths greater than 100 × 106 bytes/second and/or by throughput requirements beyond 5 × 108 arithmetic operations/second, thereby requiring specialized hardware processor implementations for their solution. Examples of such problems from biomedical environment will be presented and discussed. These large computational problems may be suitable candidates for solution by means of an emerging digital integrated circuit technology based upon Gallium Arsenide substrate material, in which the switching speed of the basic gates is enhanced. The technology of GaAs devices, the digital systems which will employ them in an optimal manner, and the tools necessary to design these systems to operate in very high frequency regimes, are described and reviewed.
An Evaluation of Written, Graphics, and Voice Messages in Proceduralized Instructions

This study evaluated written messages, graphics, combined text and graphics, and digitized voice messages as a means of communicating proceduralized instructions to a broad range of users. The value of using voice messages as a means of supplementing visually presented information was also tested. The task consisted of making a cash withdrawal from an automated teller machine (ATM) with the aid of guidance and error messages. Results indicated that graphics was inferior to text, combined text and graphics, or voice as the primary means of communicating instructions. Voice, when used to supplement the visually presented error messages, did not provide any performance advantage over visually presented information alone. The voice messages were not liked by the subjects, especially for use in a public application. The results suggest that graphics messages should not be used as the sole means of communicating proceduralized instructions. Text and combined text and graphics were found to be acceptable modes o...
Intercomparison of regular spectral transmittance and reflectance measurements with FTIR- and monochromator-based spectrophotometers

We have performed regular spectral transmittance and reflectance measurements over the 1 (mu) m to 2.5 (mu) m wavelength region on several different types of materials using three different spectrophotometer systems. Two of the systems employ grating-based monochromators and InGaAs photovoltaic detectors. The beam at the sample position is nearly collimated. The other system uses an FTIR (Fourier Transform Infrared) spectrophometer as a source and a diffuse Au-coated integrating sphere with a photoconductive HgCdTe detector. In this system, the sample is placed at the focus of an f/6 converging beam. Measurements are performed on transmissive materials as well as either highly reflective or absorptive mirrors and the results are compared, taking into account any differences in beam geometry and polarization among the different systems.
SnapShot: Inositol Phosphates

Inositol diphosphates can transfer phosphatenonenzymatically to phosphoserine to generate diphosphate modi˜ed proteinsIP6K1 (KCS1) generated inositol diphosphatesare required for proper regulation of telomere lengthIpk2 regulates activity of Swi/Snf and Ino80chromatin-remodeling complexes in yeastIP6K1 (KCS1) is required for proper vacuole morphology and responses to osmotic stressIP
Suppressor Variables and the Semipartial Correlation Coefficient

Since Horst (1941) initially introduced the concept, a number of investigators have suggested alternative definitions that both include a broader class of situations and are more precise. Following a conceptual framework suggested by Conger (1974), the present paper discusses a definition based on the relation of the semipartial correlation to the zero order correlation. This definition possesses a number of advantages, including the fact that it can be easily extended from the two predictor case to the general p-predictor case.
VASOACTIVE INTESTINAL PEPTIDE : MEDIATOR OF LAMININ SYNTHESIS IN CULTURED SCHWANN CELLS

To learn more about neuropeptide-induced glial responses which accompany axon regeneration, we studied effects of VIP on laminin production by cultured Schwann cells. Schwann cells were isolated from sciatic nerves of neonatal mice, purified, and incubated for 5 days in either control medium (DMEM + 15% FCS) or control medium containing 10−7 -10−11 M VIP. At 10−7 and 10−8 M VIP, laminin levels measured by enzyme-linked immunosorbent assay were significantly higher (55% and 35%) than those in control cultures. Lower VIP concentrations (10−9 -10−11 M) produced smaller increases which were not significant. Low-affinity VIP receptors which mediated this effect were demonstrated on Schwann cells by radioligand binding studies. The increased Schwann cell synthesis of laminin induced by VIP was blocked when either a VIP antagonist or a VIP receptor antagonist was added to the VIP-containing incubation medium. In contrast to astrocytes, when Schwann cells were loaded with fura-2, VIP did not increase cytosolic Ca2+. This indicates that Schwann cells and astrocytes may have different intracellular transduction pathways; their receptor subtypes also may differ. We suggest that the VIP-induced increase in laminin synthesis which we have observed in cultured Schwann cells may also occur in vivo and might be an important component of axon-Schwann cell interactions during nerve regeneration. © 1996 Wiley-Liss, Inc.
“I Love You, Brom Bones”: Beta Male Comedies and American Culture

The titles of current books bemoaning the child-man, regressive state of American masculinity are telling: Manning Up; Save the Males. 1 Inciting this glut of alarmist literature and embodying the ...
Are apathy and depression independently associated with longitudinal trajectories of cortical atrophy in mild cognitive impairment

Objectives To examine whether depression and apathy are independently associated with longitudinal trajectories of cortical atrophy in the entorhinal cortex compared with frontal subregions previously implicated in late-life mood disturbance. Methods Data from 334 participants classified as having mild cognitive impairment in the Alzheimer's Disease Neuroimaging Initiative (ADNI) were analyzed by using multilevel models for change adjusted for age, global cognitive status, and total intracranial volume at enrollment. Participants in ADNI were recruited from >50 clinical research sites in the United States and Canada. Depression and apathy were identified by informants using the Neuropsychiatric Inventory Questionnaire. Serial magnetic resonance imaging was performed on 1.5-Tesla scanners according to the standardized ADNI-1 protocol on an average of 5 occasions over an average of 30.5 months. Regional cortical thickness values were derived from longitudinal data processing in FreeSurfer version 4.4. Results Depression was associated with reduced cortical thickness in the entorhinal cortex at baseline and accelerated atrophy in the anterior cingulate cortex. Similar relationships between depression and the orbitofrontal cortex and between apathy and the anterior cingulate cortex were not significant. Conclusions In mild cognitive impairment, depression signs are a better marker of longitudinal cortical atrophy than apathy. Results are consistent with hypotheses that depression is an early sign of a more aggressive neurodegenerative process or that depression lowers brain reserve capacity, allowing for more rapid progression of Alzheimer disease neuropathology.
Oligomerization of mouse alpha 1-syntrophin and self-association of its pleckstrin homology domain 1 containing sequences.

Syntrophins are known to self-associate to form oligomers. Mouse α1-syntrophin sequences were produced as chimeric fusion proteins in bacteria and were found to also oligomerize and in a micromolar Ca2+-dependent manner. The oligomerization was localized to the N-terminal pleckstrin homology domain (PH1) or adjacent sequences; the second, C-terminal PH2 domain did not show oligomerization. PH1 was found to self-associate, and calmodulin or Ca2+-chelating agents such as ethylene glycol bis(β-aminoethyl ether)-N,N,N‘,N‘-tetraacetic acid (EGTA) could effectively prevent this oligomerization. A single calmodulin bound per syntrophin to cause inhibition of the precipitation. Since calmodulin inhibited syntrophin oligomerization in the presence or absence of Ca2+, Ca2+ binding to syntrophin is responsible for the inhibition by EGTA of syntrophin oligomerization.
Enzyme folding and unfolding

Abstract Different enzyme folding models are reviewed and placed in proper perspective. Some of the more contemporary models discussed include the cardboard-box model, the peptide-ribbon model, the averaging nucleus formation energies model, the lattice model, and the hydrogen bonding model. Examples taken from the literature and presented at the end of the review, highlight the different mechanisms involved and the importance of the sum-of-exponential type equation to represent the restoration of enzyme activity with time. The different models presented together provide a reasonable overall view of enzyme folding processes, and provide significant physical insight into the enzyme folding kinetics and mechanism.
Text-mining applied to autoimmune disease research: the Sjögren’s syndrome knowledge base

Sjogren’s syndrome is a tissue-specific autoimmune disease that affects exocrine tissues, especially salivary glands and lacrimal glands. Despite a large body of evidence gathered over the past 60 years, significant gaps still exist in our understanding of Sjogren’s syndrome. The goal of this study was to develop a database that collects and organizes gene and protein expression data from the existing literature for comparative analysis with future gene expression and proteomic studies of Sjogren’s syndrome. To catalog the existing knowledge in the field, we used text mining to generate the Sjogren’s Syndrome Knowledge Base (SSKB) of published gene/protein data, which were extracted from PubMed using text mining of over 7,700 abstracts and listing approximately 500 potential genes/proteins. The raw data were manually evaluated to remove duplicates and false-positives and assign gene names. The data base was manually curated to 477 entries, including 377 potential functional genes, which were used for enrichment and pathway analysis using gene ontology and KEGG pathway analysis. The Sjogren’s syndrome knowledge base ( http://sskb.umn.edu ) can form the foundation for an informed search of existing knowledge in the field as new potential therapeutic targets are identified by conventional or high throughput experimental techniques.
Time Surfaces, Vacuity, and Mappability in Stratigraphy: ABSTRACT

Recognition of regional lithologic marker beds is accelerated by refined mechanical logging techniques and adequate drilling density. These correlative "punctuations" are considered to be geologically instantaneous, and to yield time surfaces bounding reliable End_Page 484------------------------------ stratigraphic units. The enclosed units represent longer intervals of time, and their lithologic gradations represent the diluted total environmental impress. Markers represent (1) widespread, essentially contemporaneous deposition of thin lithologic components, and (2) virtually contemporaneous contact phenomena resulting from halmyrolic chemical alteration, replacement, and syngenetic emplacement proximal to the sediment-water interface during times of non-deposition. Time markers may indicate such short-interval lithologic inflictions as changes in water depth, climatic variations, migration of shoreline, and influx of suspensoids with chemical or physical character sharply differing from that of sediments within the body of the marker-bounded unit. Unit thickness of sediment deposited at any locale is dependent on sediment availability, fluxes of the scattering agent, rate of regional variation in chemical impress of depositing medium, nd amplitude of local and regional structural change. Lithologic variations occur in any unit, but the mechanical-log characters of the units are remarkably consistent through an entire sedimentary basin. If log character of unit sequence is similar, one may consider the unit to be areally equivalent not only in duration but in simultaneity. Log character is a function of space and environment, and the time markers signal massive changes in the vertical continuity of these environmental controls. Stratigraphic analysts are able to use these "time slices" to create isopachous and lithofacies maps of short-interval synchronous units. These maps are rigidly controlled for unit initiation, termination, and time span. Thickness variations represent a measure of competitive sedimentation resulting from an interplay of environmental factors which involve the allogens and syngens in sedimentary prisms of a marine basin. Paleontologic and sedimentologic characteristics in these geosynchronous units yield environmental and geographic patterns important in the delineation of porosity trends. Geosynchron maps permit analysis of intra-basin structural growth which influences first-phase oil migration. Time-length vacuity becomes susceptible to quantitative analysis. If the generally accepted concepts of uniformitarian geology are approximately correct, these maps systematize haphazard lithologic patterns into geographic and time-controlled stratal units whose internal characteristics make it possible to determine rates of sedimentation, facies gradation, lateral intensities of environmental impress, origins of sediments, depth of water, distance to shore, and a host of other sedimentational variables not otherwise easily susceptible to quantification. End_of_Article - Last_Page 485------------
In vitro Interaction of LSD with Purified Calf Thymus DNA

THE observation of broken chromosomes in test animals and humans treated with the hallucinogen lysergic acid diethylamide (LSD) has been well documented1–8. Although there has been some speculation about the mode of action of the drug, no specific studies of the mechanism of LSD-induced chromosomal damage have, as yet, been presented. Such studies would be most useful in determining whether LSD interacts directly with the chromosome which becomes broken or whether chromosomal breakage is the result of a series of biochemical events begun by LSD at some site distant from the chromosome. This communication describes circular dichroism experiments which indicate that LSD interacts directly with purified calf thymus DNA, probably by intercalation, causing conformational changes in the DNA. It is suggested that this observed interaction may serve as a model for the action of LSD on the chromosomal material of intact cells.
Calculations of electron inelastic mean free paths from experimental optical data

Etude pour C, Mg, Al, Al 2 O 3 , Cu, Ag, Au et Bi. Les calculs necessitent la connaissance de la variation du transfert de moment avec la section efficace de diffusion differentielle que l'on obtient a partir des calculs de Penn
The Costs of Cultural Change: Accidental Injury and Modernization among the Papago Indians.

The health status of American Indians today is in transition between preindustrial and modern patterns of morbidity and mortality. As traditional causes of diseases and death tend to recede, however, an unexpected threat to life has gained increasing importance. Accidental deaths account for more than one-fifth of all United States Indian mortality and are responsible for three times more deaths among Indians than among Whites. Unlike better known social pathologies (alcoholism, homicide), accidental injuries and deaths are evenly distributed across age-sex categories and rural and urban Indian populations.This paper examines several theories suggesting that stresses associated with modernization are responsible for excesses of accidental injuries among Indians. Alternative hypotheses which seek to locate individuals under greatest stress in traditional or modern villages are described and tested, using data on accidental injuries collected in an ongoing study of accident epidemiology among the Papago Ind...
Use of Proteomics to Demonstrate a Hierarchical Oxidative Stress Response to Diesel Exhaust Particle Chemicals in a Macrophage Cell Line

Epidemiological studies demonstrate an association between short term exposure to ambient particulate matter (PM) and cardiorespiratory morbidity and mortality. Although the biological mechanisms of these adverse effects are unknown, emerging data suggest a key role for oxidative stress. Ambient PM and diesel exhaust particles (DEP) contain redox cycling organic chemicals that induce pro-oxidative and pro-inflammatory effects in the lung. These responses are suppressed by N-acetylcysteine (NAC), which directly complexes to electrophilic DEP chemicals and exert additional antioxidant effects at the cellular level. A proteomics approach was used to study DEP-induced responses in the macrophage cell line, RAW 264.7. We demonstrate that in the dose range 10–100 μg/ml, organic DEP extracts induce a progressive decline in the cellular GSH/GSSG ratio, in parallel with a linear increase in newly expressed proteins on the two-dimensional gel. Using matrix-assisted laser desorption ionization time-of-flight mass spectrometry and electrospray ionization-liquid chromatography/mass spectrometry/mass spectrometry analysis, 32 newly induced/NAC-suppressed proteins were identified. These include antioxidant enzymes (e.g. heme oxygenase-1 and catalase), pro-inflammatory components (e.g. p38MAPK and Rel A), and products of intermediary metabolism that are regulated by oxidative stress. Heme oxygenase-1 was induced at low extract dose and with minimal decline in the GSH/GSSG ratio, whereas MAP kinase activation required a higher chemical dose and incremental levels of oxidative stress. Moreover, at extract doses >50 μg/ml, there is a steep decline in cellular viability. These data suggest that DEP induce a hierarchical oxidative stress response in which some of these proteins may serve as markers for oxidative stress during PM exposures.
Effects of mixing on the composition and morphology of tissue‐engineered cartilage

Cartilage constructs were grown using isolated chondrocytes and biodegradable polymer scaffolds made of fibrous polyglycolic acid in the form of 1-cm-dia × 5-mm-thick discs. The scaffolds were seeded in a mixed cell suspension and cultured for up to 8 weeks under static or mixed tissue culture conditions in petri dishes and spinner flasks. Turbulent mixing significantly improved the biochemical compositions and altered morphologies of the cartilage constructs, which were the thickest ones cultured to date in vitro. Constructs from mixed cultures were more regular in shape and contained up to 70% more cells, 60% more sulfated glycosaminoglycan, and 125% more total collagen when compared to constructs from static cultures. Mixing also induced the formation of an outer capsule with multiple layers of elongated cells and collagen fibrils around the inner tissue phase, while statically grown constructs consisted of round cells embedded in cartilaginous matrix. Mixing during cell seeding and tissue culture is thus an important parameter for the cultivation of tissue-engineered cartilage in a range of sizes, shapes and compositions for a variety of clinical applications (e.g., fibrous cartilage for reconstructive surgery or articular cartilage for joint resurfacing).
The letter of the law: Abelard, Moses, and the problem with being a eunuch

Abstract When Peter Abelard (ca. 1079–1142) was involuntarily castrated, he was, according to his own account, severely distressed by the subsequent pain, public humiliation, and change of life. Such a response seems hardly surprising. But then he was equally distressed by the recollection of two commands of the Mosaic Law (Leviticus 22:24 and Deuteronomy 23:1), according to which eunuchs are, in his words, rejected as an ‘abomination before God’. And this latter admission is surprising indeed, given that Christian exegesis of these two verses up to Abelard’s time was universally spiritual. There was an apparent consensus that nothing in the letter of these laws had any bearing on Christian thought or life; they were certainly not cited as reasons for condemning or legally restricting eunuchs in Christianity. Yet Abelard is tempted to condemn at least himself as unclean on the basis of the Levitical mandates. What explains his innovation? Abelard’s Levitical lament is not, as some have suggested, a further manifestation of his fear of humiliation, nor is it an expression of concern about his legal status in the church. Abelard’s distress about Levitical restrictions on eunuchs is consistent with and explained by the reasoned, largely positive reassessment of the value of the Law, as understood according to the letter, that he advances in his theoretical works on the Bible and Christian doctrine.
Gasoline selective ZSM-5 FCC additives: effects of crystal size, SiO2/Al2O3, steaming, and other treatments on ZSM-5 diffusivity and selectivity in cracking of hexene/octene feed

Abstract ZSM-5 catalysts with silica/alumina ratios of 55/1 and 450/1, and with varying crystal size, were studied to better understand the operation of “gasoline selective” FCC additives. Most materials were steamed for 5 h at 1400°F, and some were subjected to other treatments such as mechanical milling, P addition, and HCl reflux. These materials were characterized for total Al content, tetrahedral Al, and sorption capacity and rate. The ratios of octene isomerization to octene cracking, and of octene cracking to hexene cracking, for a mixed hexene/octene feed at 538°C were used to assess the potential FCC gasoline selectivity of these catalysts. Steaming generally led to a decrease in effective diffusivity, as calculated from uptake rates. HCl reflux of two steamed samples removed substantial quantities of non-framework alumina, resulting in increased diffusivities and higher selectivities. Density of acid sites did not appear to be important in determining the gasoline selectivity of the catalysts examined here. The effects of most catalyst treatments on reaction selectivities could be related to diffusional blockage, especially by non-framework alumina. However, not all results could be explained by a simple reaction/diffusion model. Factors other than diffusion, such as narrowing of available reaction space in the ZSM-5 channels, may also play a role in determining selectivities.
Electric-field effects on the optical vibrations in AB-stacked bilayer graphene

Using first-principles methods, we show that an applied perpendicular electric field $E$ breaks the inversion symmetry of AB-stacked bilayer graphene (BLG), thereby slightly mixing the two in-plane high-energy optical vibrations (${E}_{g}$ and ${E}_{u}$ modes). The mixed amplitudes increase parabolically with respect to the field strength when $El2.0$ V/nm, and then exhibit linear dependence when $Eg2.0$ V/nm. In contrast, the mixing effect on the out-of-plane vibrations (${A}_{1g}$ and ${A}_{2u}$ modes) is found to be much stronger, with the mixed amplitudes nearly an order of magnitude larger than those for the in-plane modes. For the two in-plane modes, we then calculate their phonon linewidths and frequency shifts as a function of the electric field as well as the Fermi level. Our results reveal delicate interplay between electrons and phonons in BLG, tunable by the applied fields and charge carrier densities.
Contention elimination by replication of sequential sections in distributed shared memory programs

In shared memory programs contention often occurs at the transition between a sequential and a parallel section of the code. As all threads start executing the parallel section, they often access data just modified by the thread that executed the sequential section, causing a flurry of data requests to converge on that processor.We address this problem in a software distributed shared memory system by replicating the execution of the sequential sections on all processors. Communication during this replicated sequential execution is reduced by using multicast.We have implemented replicated sequential execution with multicast support in OpenMP/NOW, a version of of OpenMP that runs on networks of workstations. We do not rely on compile-time data analysis, and therefore we can handle irregular and pointer-based applications. We show significant improvement for two pointer-based applications that suffer from severe contention without replicated sequential execution.
Structure of porphyrins in relation to reversible oxidation and reduction reactions

Abstract A variety of porphyrin derivatives were synthesized in order to determine the effect of certain structural features on the oxidation-reduction properties of these complexes. It was found that a fifth ring, such as the isocyclic ring of chlorins was without significant effect on the one-electron oxidation properties of a magnesium tetrahydroporphyrin (bacteriochlorophyll), Fe(II) porphyrin complexes, or Fe(II) chlorin complexes. On the other hand, large positive shifts of the midpoint potentials for oxidation of Fe(II) derivatives were found when the porphyrin ring was reduced to a chlorin structure.
Equivalence of Room designs. II

Abstract The relation of equivalence of Room designs is investigated with respect to the class of Room designs formed from starters with adders in the conventional way. It is shown that, if pk = 3 + 4t, s = t − 2[ t 2 ] , and I = ( 1 k ) ∑ d k P d φ ( k d ), then it is possible to construct, without duplication, at least (I + (−3) 1–8 ) 8 inequivalent patterned Room designs of side pk. This result implies, for instance, the existence of at least 11 equivalence classes of Room designs of side 87 which contain a patterned Room design; it also implies the existence of at least 5 · 105 equivalence classes of Room designs of side 79 which contain a patterned Room design. Some additional results are obtained.
Super-resolution for high magnification face images

Most existing face recognition algorithms require face images with a minimum resolution. Meanwhile, the rapidly emerging need for near-ground long range surveillance calls for a migration in face recognition from close-up distances to long distances and accordingly from low and constant resolution to high and adjustable resolution. With limited optical zoom capability restricted by the system hardware configuration, super-resolution (SR) provides a promising solution with no additional hardware requirements. In this paper, a brief review of existing SR algorithms is conducted and their capability of improving face recognition rates (FRR) for long range face images is studied. Algorithms applicable to real-time scenarios are implemented and their performances in terms of FRR are examined using the IRISLRHM face database [1]. Our experimental results show that SR followed by appropriate enhancement, such as wavelet based processing, is able to achieve comparable FRR when equivalent optical zoom is employed.
Motion-based visual behaviors for mobile robots

We investigate two specific visual motion behaviors that are appropriate for mobile robot applications because of their simplicity and low computational load. The first behavior determines the distance to a flat wall to the side of the moving robot. Such a measurement is essential for a wall-following behavior. The second behavior determines the projected amount of time until the robot collides with a stationary object assuming that the robot continues to move at a constant velocity. This time-to-contact estimate relies on the expansion of the optical flow field and can act as a collision-warning sensor to warn of impending obstacles. The numberical estimates given by both behaviors are expressed as simple ratios of easily measured visual quantities and do not require any elaborate calibration procedures. These behaviors use a 1D patch-wise correlation technique that was developed by Poggio and Ancona. We have further simplified the computation and show results on true image sequences.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Four-stream isosector approximation for canopy radiative transfer

[1] This study develops an analytical four-stream isosector approximation for solar radiative transfer in a homogeneous canopy, based on the approximation of four spherical sectors of isotropic intensities (constant values for light intensities). Compared to results from a multilayer radiative transfer model, the four-stream isosector approximation substantially improves the accuracy in calculation of albedo, transmittance, and absorptance with respect to the corresponding two-stream approximation. For direct incident radiation, it has errors mostly under 5% for leaf area index less than 5, even when sun angles are very low, while the two-stream method has errors of about 10% or higher; more improvement is achieved in albedo and transmittance in the visible band, and transmittance and absorptance in the near-infrared (NIR) band. For diffuse incident radiation, both the two-stream and four-stream approximations always have a higher accuracy in the NIR band than in the visible band, but the improvement of the four-stream approximation is larger for the visible band than for the NIR band. In addition, they have a higher accuracy in describing canopy albedo, transmittance and absorption for direct incident radiation than for diffuse incident radiation. However, the improvement of the four-stream is higher for diffuse incident radiation than for direct incident radiation. The inclusion of soil albedo as the low boundary does not degrade the performance of the four-stream approximation. As an analytical model, the four-stream approximation can be easily applied as an efficient approach to improving the parameterization of land surface radiation in climate models.
The Big, Bad Wolf: Resisting Corporate Evil in “Damages” and State of Play

Two recent popular entertainments, the television series “Damages” and the movie State of Play, have business organizations and people in the roles of villains. As thrillers, they employ the conventions that allow the audience to identify the good guys and the bad guys. The fact that business is an institutional area that can be so easily accepted as the source of evil indicates a new attitude in our society that is a response to recent events.
Political Style and Military Expenditures

Summary.-In 18 industrialized nations in 1960, dimensions of political style which predicted social welfare spending did not predict defense spending. Among eighteen industrialized democracies, Hicks and Swank (1992) found that three dimensions of political institutions (left corporatism, state centralization, and bureaucratic patrimonialism) were associated with expenditures on social welfare. The present note explored whether these three dimensions of political style predicted defense expenditures in the same countries. For 18 industrialized nations, namely, Australia, Austria, Belgium, Canada, Denmark, Finland, France, Ireland, Italy, Japan, The Netherlands, New Zealand, Norway, Sweden, Switzerland, the United Kingdom, the United States of America, and West Germany, factor scores on these three'dimensions of political institutions were obtained for 1960 from Hicks and Swank (1992), and expenditure on defense as a percentage of gross national product and military personnel as a percentage of the population aged 15 to 64 years from Russett (1964). Defense expenditures were not associated with left corporatism, state centralization, or bureaucratic patrimonialism (Pearson rs = 0.19, -0.06, and -0.21, respectively) and neither were the military participation rates (rs =O.Oi', 0.34, and 0.04, respectively). Although the nations' political styles predicted welfare spending, this measure did not predict defense spending.
Longitudinal and seasonal variation of stream N uptake in an urbanizing watershed: effect of organic matter, stream size, transient storage and debris dams

We examined seasonal and spatial linkages between N cycling and organic matter for a suburban stream in Maryland and addressed the question: How do longitudinal NH4 + uptake patterns vary seasonally and what is the effect of organic matter, stream size, transient storage and debris dams? We applied a longitudinal (stream channel corridor) approach in a forested stream section and conducted short-term nutrient addition experiments (adapted to account for the effect of nutrient saturation) covering 14–16 reaches, and compared two distinct seasons (late fall 2003 and late summer 2004). Longitudinal NH4 + uptake rate patterns had a distinct seasonal reversal; fall had the highest uptake rates in the upper reaches, while summer had the highest uptake rates in the lower reaches. This seasonal reversal was attributed to organic matter and evidenced by DON patterns. Transient storage did not have an expected effect on uptake rates in fall because it was confounded by leaf litter; litter produced higher uptakes, but also may have reduced transient storage. In summer however, uptake rates had a positive correlation with transient storage. Debris dams had no distinct effect on uptake in fall because of their recent formation. In summer however, the debris dam effect was significant; although the debris dams were hydraulically inactive then, the upstream reaches had 2–5 fold higher uptake rates. The seasonal and longitudinal differences in NH4 + uptake reflect interactions between flow conditions and the role of organic matter. Urbanization can alter both of these characteristics, hence affect stream N processing.
Enzyme-Assisted Preparation of Fibrillated Cellulose Fibers and Its Effect on Physical and Mechanical Properties of Paper Sheet Composites

The fabrication of fibrillated cellulose fibers and their utilization have been of more interest recently because of their biodegradability, low cost, and mechanical and thermal properties comparable to those of glass fibers or carbon fibers. In this study, we applied the combination of a mechanical shearing process with a cooling system and an enzymatic pretreatment to produce fibrillated cellulose fibers from softwood pulps. The effects of the mechanical shearing process, the cooling system, and the enzymatic treatment on the formation of the fibrillated cellulose fibers as well as physical and mechanical properties of paper were investigated. It was indicated that the cooling system was necessary in the grinding process to prevent the adverse effect of heat generation on mechanical properties of paper sheets. It was observed that the enzyme-assisted mechanical shearing process improves the production of fibrillated cellulose fibers and results in a substantial improvement of tensile strength and elonga...
Subjective confidence in forecasts: A response to fischhoff and MacGregor

ABSTRACT Here we evaluate the generalizability of calibration studies which have used general knowledge questions, and argue that on conceptual, methodological and empirical grounds the results have limited applicability to judgemental forecasting. We also review evidence which suggests that judgemental forecast probabilities are influenced by variables such as the desirability, imminence, time period and perceived controllability of the event to be forecast. As these variables do not apply to judgement in the domain of general knowledge, a need for research recognizing and exploring the psychological processes underlying uncertainty about the future is apparent. KEY WORDS Calibration Judgemental forecasting Subjective probability This paper reviews recent psychological research that has relevance for judgemental forecasting. Judgemental forecasts are often required in situations where actuarial, or relative frequency, data are unavailable or known to be unreliable. These judgements can be used as inputs to decision analysis and probabilistic information processing systems, which are based on subjective expected utility theory and Bayes’ theorem, respectively. (For a review of these decision aids see Wright (1984)). Economists have identified a need for judgemental forecasts when there is seen to be a possibility of ‘turning points’ in time series data. The recognition of the possibility of such turning points may be made on the basis of observing discontinuous changes in variables that are assumed to have a causal influence on the criterion variable. For example, consider the impact of the miners’ strike in the United Kingdom upon
False recognition of associates: How robust is the effect?

False recognition of nonpresented words that were strong associates of 12 words in a study list was examined. Six lists were read to subjects; each list contained the 12 strongest associates to a critical nonpresented word. False-alarm rates to the 6 critical nonpresented words were obtained under several different conditions. The manipulations included varying the level of processing done to the study lists, varying the recognition-test procedure, repeating each of the study lists three times, and mixing the words from the six study lists together. A reliable false-recognition effect for critical nonpresented words was obtained in all conditions. However, the effect was not impervious to all of the manipulations. Significantly lower false recognition was obtained when learning was incidental as well as when the words on the six lists were mixed together. Neither level of processing nor repetition significantly influenced false recognition. This last result is inconsistent with Hintzman’s (1988) MINERVA 2 global memory model, but agrees with predictions from Shiffrin, Ratcliff, and Clark’s (1990) SAM model.
Bamboo shaped carbon nanotube supported platinum electrocatalyst synthesized by high power ultrasonic-assisted impregnation method for methanol electrooxidation and related density functional theory calculations

Abstract Carbon nanotubes (CNTs) with special forms may exhibit novel properties, which are different compared to conventional carbon nanotubes and may open a way for future applications. The nanotubes with a bamboo-like structure due to nitrogen doping have been well studied because of the increased attention for their bamboo shaped structure associated properties. In this work, bamboo shaped carbon nanotubes (BCNTs), synthesized by chemical vapor deposition (CVD) method, were investigated for direct methanol fuel cells (DMFC). Small sized platinum nanoparticles (Pt NPs) were dispersed onto BCNT surface through a high power ultrasonic-assisted impregnation method in a short time. The structure and nature of the resulting Pt NP coated BCNT composites (Pt/BCNTs) were characterized by Transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Energy dispersive spectroscopy (EDS). Density functional theory (DFT) calculations of Pt NPs coated on different structural CNTs showed that inclusion of nitrogen improved the catalytic performance of carbon nanotubes toward methanol electrooxidation. High electrochemical activity of BCNTs supported Pt NPs was demonstrated by the electrochemical studies.