cssi/SciSciGPT-SciSciNet huggingface dataset:
Penalized pseudo-likelihood hazard estimation: A fast alternative to penalized likelihood

Abstract Penalized likelihood method has been developed previously for hazard function estimation using standard left-truncated, right-censored lifetime data with covariates, and the functional ANOVA structures built into the log hazard allows for versatile nonparametric modeling in the setting. The computation of the method can be time-consuming in the presence of continuous covariates; however, due to the repeated numerical integrations involved. Adapting a device developed by Jeon and Lin [An effective method for high dimensional log-density ANOVA estimation, with application to nonparametric graphical model building. Statist. Sinica 16, 353–374] for penalized likelihood density estimation, we explore an alternative approach to hazard estimation where the log likelihood is replaced by some computationally less demanding pseudo-likelihood. An assortment of issues are addressed concerning the practical implementations of the approach including the selection of smoothing parameters, and extensive simulations are presented to assess the inferential efficiency of the “pseudo” method as compared to the “real” one. Also noted is an asymptotic theory concerning the convergence rates of the estimates parallel to that for the original penalized likelihood estimation.
Paper chromatography of 2,4-dinitrophenylsulfide derivatives of mercaptans and mercapto-acids

Abstract Ascending paper chromatographic methods for the separation of 2,4-dinitrophenylsulfide derivatives of mercaptans and mercapto-acids are presented. A solvent system composed of methanol as the stationary phase and heptane as the mobile phase gave satisfactory separations of the normal C 1 to C 7 mercaptan derivatives on What-man No. 1 paper. Two procedures were devised to separate the mercapto-acids derivatives. One method employed a solvent system of n -butanol:ethanol:water (20:5:25) with the water-rich layer as the stationary phase and the butanol-rich layer as the mobile phase. The solvent system for the second procedure was composed of equal parts of benzene and 1% acetic acid with the benzene-rich layer as the mobile phase in this case.
Mutación discursiva en las Ciencias Sociales chilenas. Lecturas de un texto de Francisco Gallardo

En este articulo daremos cuenta del surgimiento en los ultimos 25 anos en Chile de un tipo textual original bastante desconocido para los circuitos academicos que representa un desafio desde el punto de vista de su clasificacion y analisis; denominamos al conjunto de estos textos como «antropologia poetica». Nuestro intento de ubicar nuestra interrogante tipologica en el tema puntual del «genero» en el cual seria posible ubicar a estas obras. La hipotesis del presente articulo consistira en afirmar que el conjunto de obras compuesto por la «antropologia poetica chilena» consiste basicamente en un tipo distinto de produccion textual, iniciadora de un nuevo genero discursivo. Con este fin se analiza una obra representativa de esta corriente, el libro del chileno Francisco Gallardo "Antropologia. Cruzando a traves de", obra que expresa de manera especialmente nitida la originalidad de la Antropologia Poetica Chilena.
Imidazole catalysis in carbamate and polyurethane formation

Polyurethanes have been prepared from the reactions of the diimidazole and ditriazole adducts of 2,4-toluene diisocyanate and ethylene glycol or polyols. Suitable formulations have been developed from these components which are useful in preparing polyurethane coatings and foams. Imidazole was established as an effective catalyst for the reactions of the diphenol adduct of 2,4-toluene diisocyanate with polyols. Imidazolecatalyzed polyurethane formation from the phenol-blocked diisocyanate occurs readily between 100° and 140°C. A mechanism for the catalytic activity of imidazole in these reactions is proposed.
Chemical yield optimization of the benzene synthesis for radiocarbon dating

Abstract A benzene synthesis vacuum line for radiocarbon dating is described. Operating precautions are outlined that permit the reduction of secondary reactions and lead to desired product yields consistently in excess of 95%. The total procedure has been shortened for most archaeological samples by the substitution of a preliminary carbonization step for the usual combustion. Principal secondary reactions in the lithium carbide production have been identified. Low chemical yields here are due to the presence of vacuum line leaks, excessive moisture, or insufficient heating at the end of the reaction. The production of lithium carbonate and some elemental carbon account for the losses. A potassium chromate-activated silica-alumina catalyst is used for the cyclization of acetylene to benzene. It is deactivated in secondary reactions by a reduction of the chromium VI to chromium III or IV oxidation states. The presence of moisture in the acetylene and/or catalyst is responsible for low benzene yields and increased catalyst deactivation rates. A mechanism is proposed involving reaction of acetylene with water to form acetaldehyde, which is subsequently oxidized to acetate, polymerization products, and potassium carbonate. Thorough desiccation of the acetylene and catalyst permits close to quantitative production of benzene. The catalyst can be reactivated by heating in air to 500°C.
The coupling of conical wrinkled laminar flames with gravity

Abstract This work explores the influences that gravity has on conical premixed laminar and mildly turbulent flames (i.e., wrinkled laminar flames). The approach is to compare overall flame characteristics in normal (+ g ), reverse (− g ), and micro-gravity ( μg ). Laser schlieren is the principal diagnostic for the μg experiments. Laboratory investigation of + g and − g flames also include two components laser doppler anemometry. The results obtained in a wide range of flow, mixture and turbulence conditions show that gravity has a profound effect on the lean stabilization limits, features of the flowfield, and mean flame heights. In + g , buoyancy driven instability causes flame flickering. Without this unstable interaction, flames in − g and μg do not flicker. Analysis of the flame flickering frequencies produces in an empirical relationship St ∗2 /Ri = 0.0018 Re 2 3 (where St ∗ , Ri, and Re are, respectively, the Strouhal number normalized by the heat release ratio, the Richardson number, and the Reynolds number). This correlation would be useful for theoretical prediction of buoyancy induced flame instabilities. Comparison of mean flame heights shows that + g , − g , and μg flame properties do not converge with increased flow momentum. Velocity measurements in laminar flames show that in + g , the flow generated by the rising products plum is almost non-divergent, slightly turbulent and unstable. In − g , the flow becomes divergent, but is stable and non-turbulent in the region surrounding the flame cone. The change from a nondivergent to divergent flow field seem to account for the differences in the observed mean flame heights. The schlieren images and the velocity measurements in + g and − g also provide some insight into the overall flowfield features of μg flames.
Spartacus: spatially-aware interaction for mobile devices through energy-efficient audio sensing

Recent developments in ubiquitous computing enable applications that leverage personal mobile devices, such as smartphones, as a means to interact with other devices in their close proximity. In this paper, we propose Spartacus, a mobile system that enables spatially-aware neighboring device interactions with zero prior configuration. Using built-in microphones and speakers on commodity mobile devices, Spartacus uses a novel acoustic technique based on the Doppler effect to enable users to accurately initiate an interaction with a neighboring device through a pointing gesture. To enable truly spontaneous interactions on energy-constrained mobile devices, Spartacus uses a continuous audio-based lower-power listening mechanism to trigger the gesture detection service. This eliminates the need for any manual action by the user. Experimental results show that Spartacus achieves an average 90% device selection accuracy within 3m for most interaction scenarios. Our energy consumption evaluations show that, Spartacus achieves about 4X lower energy consumption than WiFi Direct and 5.5X lower than the latest Bluetooth 4.0 protocols.
A rigorous solution of the Navier-Stokes equations for unsteady viscous flow at high Reynolds numbers around oscillating airfoils

A method based on the Navier-Stokes equations was developed for analyzing the unsteady incompressible viscous flow around oscillating airfoils at high Reynolds numbers. The Navier-Stokes equations have been integrated in their classical Helmholtz vorticity transport equation form, and the instantaneous velocity field at each time step was determined by the solution of Poisson's equation. A refined finite element was utilized to allow for a conformable solution of the stream function and its first space derivatives at the element interfaces. A corresponding set of accurate boundary conditions was applied; thus obtaining a rigorous solution for the velocity field. The details of the computational procedure and examples of computed results describing the unsteady flow characteristics around the airfoil are presented.
Thermal acclimation of metabolism in salamanders: fact or artefact?

Abstract 1. 1.|The rate of O2 consumption ( V o 2 ) was measured in the salamanders Desmognathus ochrophaeus, Plethodon cinereus and Plethodon jordani to examine the interaction of repeated measurements, feeding, duration of equilibration to respirometers and duration of acclimation with thermal acclimation of metabolism. 2. 2.|Measurements of the V o 2 of individual D, ochrophaeus for 8 consecutive days showed no consistent increase or decrease. 3. 3.|Feeding resulted in a prolonged elevation in V o 2 . The V o 2 of P. jordani increased by 77% on the day after feeding, did not begin to decline until 6 days after feeding, and still had not returned to initial levels after 11 days. 4. 4.|The post-feeding elevation in V o 2 can mimic thermal acclimation of metabolism. P. jordani that were fed immediately before acclimation to 5°C had a higher V o 2 than both unfed salamanders acclimated to 5°C and fed salamanders acclimated to 17.5°C. The V o 2 of the latter groups were similar. 5. 5.|Acclimation to a warm temperature (17.5°C) required more than 1 week for completion. Significant metabolic acclimation occurred after 2–3 days. 6. 6.|Individual D. ochrophaeus varied in both V o 2 and the rate of thermal acclimation of metabolism.
Agriculture, Forestry, and Related Benefits of Air Pollution Control: A Review and Some Observations

The author reviews and discusses current economic estimates of the costs and benefits for the agricultural sector of air pollution control. After evaluating recent benefit assessments dealing with individual receptor categories for specific air pollutants and acid rain, he focuses on problems in the use of pollutant, site, and time-specific welfare measures to develop aggregate indicators of control efficiency. The analysis covers the effect of pollutants on forests and forest ecosystems, materials, and visibility. 26 references, 1 table.
Occupational Therapy in the Home for Nonhomebound Patients

Home health services are most typically associated with care provided posthospitalization for homebound patients. Occupational therapists are often part of the posthospitalization home care team to provide training in activities of daily living. The home environment is often the more authentic location to continue to provide training in these skills even when the homebound criterion is no longer met. There are other conditions that warrant skilled occupational therapy in the home even when there has not been a hospitalization. Increased awareness of the benefit of occupational therapy in the home, along with available reimbursement options, will hopefully improve knowledge for appropriate referrals. The future holds a need for more occupational therapists to choose to work in home care.
A Framework for Capturing the Hidden Stakeholder System

As programs rise in intricacy and scope, the number of stakeholders involved also increases, often driving an exponential growth in program complexity. This complexity is caused by the stakeholder relationships which form an underlying system that influences all aspects of the program. Understanding, managing, and leveraging this stakeholder system will greatly increase a program's probability of success. This paper provides a framework for capturing this stakeholder system in a series of architectural views. These architectural products document the program's stakeholder concerns and also illustrate how those stakeholders interrelate over the system's lifecycle. The ultimate objective for the framework and use of the resulting products is to allow for right-sized stakeholder involvement, promote effective use of resources, and increase the probability of overall program success with the assurance of lasting stakeholder commitment. Additionally, this unique insertion of Stakeholder Analysis and Social Network Analysis into an Architecture Framework fulfills an original intent of Architecture Framework, capturing the entire sociotechnical enterprise system. ©2012 Wiley Periodicals, Inc. Syst Eng 16
A guide to the literature for undergraduate and graduate courses in numerical mathematics

This report contains a compilation of selected references which have been useful in the preparation of lectures and in assigning outside reading for the numerical mathematics courses taught in the Department of Computer Science at Southern Methodist University. Introductory remarks describe the environment in which the courses are taught as well as criteria for reference selection. The references are divided up into eleven sections:1. General Texts; 2. Numerical Approximation, Interpolation, and Extrapolation; 3. Numerical Integration and Differentiation; 4. Numerical Linear Algebra; 5. Numerical Solution of Differential Equations; 6. Software Influences; 7. Symbolic and Algebraic Manipulation; 8. Computational Complexity; 9. Hardware Influences; 10. Computer arithmetic; 11. Recommended Periodicals. In addition, many of the references are placed in one or more of three categories: generally-recognized classics in a subject area; relatively applied presentations; works containing extensive bibliographical material. Brief descriptions of the courses which utilize the references are included along with a list of sources for research and technical reports.
The Mechanism of Expansion and the Volatility it created in Three Pheromone Gene Clusters in the Mouse (Mus musculus) Genome

Three families of proteinaceous pheromones have been described in the house mouse: androgen-binding proteins (ABPs), exocrine gland-secreting peptides (ESPs), and major urinary proteins (MUPs), each of which is thought to communicate different information. All three are encoded by large gene clusters in different regions of the mouse genome, clusters that have expanded dramatically during mouse evolutionary history. We report copy number variation among the most recently duplicated Abp genes, which suggests substantial volatility in this gene region. It appears that groups of these genes behave as low copy repeats (LCRs), duplicating as relatively large blocks of genes by nonallelic homologous recombination. An analysis of gene conversion suggested that it did not contribute to the very low or absent divergence among the paralogs duplicated in this way. We evaluated the ESP and MUP gene regions for signs of the LCR pattern but could find no compelling evidence for duplication of gene blocks of any significant size. Assessment of the entire Abp gene region with the Mouse Paralogy Browser supported the conclusion that substantial volatility has occurred there. This was especially evident when comparing strains with all or part of the Mus musculus musculus or Mus musculus castaneus Abp region. No particularly remarkable volatility was observed in the other two gene families, and we discuss the significance of this in light of the various roles proposed for the three families of mouse proteinaceous pheromones.
Quaternary structure of vaccinia virus thymidine kinase

Thymidine kinase enzymes isolated from a variety of sources are generally considered to have a native molecular weight of 80–90 kDa composed of two 40–45 kDa subunits. Although these parameters may accurately describe the atypical deoxypyrimidine kinases expressed by members of the Herpesviridae, the nucleotide sequences of thymidine kinase genes isolated from human, mouse, chicken and a variety of poxviruses (vaccinia virus, monkeypox virus, variola virus, fowlpox virus and capripoxvirus) predict molecular weights on the order of 20–25 kDa for the derived primary translation products. To resolve this apparent dilemma, velocity sedimentation centrifugation, gel filtration chromatography and protein cross-linking procedures were employed to provide experimental evidence that enzymatically-active vaccinia virus thymidine kinase is a homotetrameric complex of 20 kDa monomers with a native Mr of 80 kDa.
Observation of an Acryloyl-Thiamin Diphosphate Adduct in the First Step of Clavulanic Acid Biosynthesis

The first committed biosynthetic step toward clavulanic acid, the clinically important beta-lactamase inhibitor, is catalyzed by the thiamin diphosphate (ThDP)-dependent enzyme N2-(2-carboxyethyl)arginine synthase (CEAS). This protein carries out a unique reaction among ThDP-dependent processes in which a C-N bond is formed, and an electrophilic acryloyl-thiazolium intermediate of ThDP is proposed to be involved, unlike the nucleophilic enamine species typically generated by this class of enzymes. Here we present evidence for the existence of the putative acryloyl adduct and report the unexpected observation of a long-wavelength chromophore (lambda = 433 nm), which we attribute to this enzyme-bound species. Chemical models were synthesized that both confirm its expected absorption (lambda = 310-320 nm) and exclude self-condensation and intramolecular imine formation with the cofactor as its cause. Circular dichroism experiments and others discount charge transfer as a likely explanation for the approximately 120 nm red shift of the chromophore ( approximately 25 kcal). Examples are well-known of charged molecules that exhibit significantly red-shifted UV-visible spectra compared to their neutral forms as, for example, polyene cations and dyes such as indigo and the cyanines. Rhodopsin is the classic biochemical example where the protein (opsin)-bound protonated Schiff base of retinal displays a remarkable range of red-shifted absorptions modulated by the protein environment. Similar tuning of the chromophoric behavior of the enzyme-bound CEAS acryloyl.ThDP species may be occurring.
Incorporation of Y'-Ty1 cDNA destabilizes telomeres in Saccharomyces cerevisiae telomerase-negative mutants.

Ty1 retrotransposons in Saccharomyces cerevisiae are activated by telomere erosion. Ty1-dependent reverse transcription of mRNA from subtelomeric Y′ repeats generates chimeric Y′-Ty1 cDNA. Here, we show that Y′-Ty1 cDNA is incorporated at eroding telomeres in the absence of telomerase. Telomeric incorporation of Y′-Ty1 cDNA promotes genome rearrangements.
Nuclear Data Sheets for A = 248☆

Abstract Detailed level schemes, decay schemes, and the experimental data on which they are based are presented for all nuclei with mass number A=248. The experimental reaction and decay data are evaluated; inconsistencies and discrepancies are noted; and adopted values are given for various level properties (including spin and parity, halflife, and configuration), γ properties (including energy, intensity, and multipole character) and α properties (including energy, intensity, and hindrance factor). This evaluation replaces the A=248 evaluation published by A. Akovali in Nuclear Data Sheets 87, 249 (1999).
Fixed vs nonfixed coronary stenosis: The response to a fall in coronary pressure in a canine model

The resistance of a coronary stenosis capable of passive vasomotion may change in response to alterations in intraluminal pressure. We studied the effects of a fall in perfusion pressure on the hemodynamics of two types of coronary stenosis in 12 open chest dogs: 1) a stenosis produced by placing a soft wire snare around the artery, and 2) a stenosis that was fixed in severity, produced by introducing and tying a short section of hollow plastic tubing into the coronary artery. Aortic pressure, coronary pressure proximal and distal to the stenosis, and coronary flow were measured. Pressure in the stenotic artery was lowered by tightening a snare placed very proximally on the artery. In arteries with a snare stenosis, lowering proximal coronary pressure by a mean of 31 mm Hg caused a rise in stenosis resistance from 0.86 +/- 0.06 to 1.38 +/- 0.14 units (p less than 0.001). However, in arteries with a fixed plastic stenosis, lowering the proximal coronary pressure by a mean of 30 mm Hg caused a fall in stenosis resistance from 0.36 +/- 0.04 to 0.21 +/- 0.03 units ( p less than 0.001). The increase in resistance of the snare stenoses as pressure was lowered may be attributed to passive narrowing of the stenotic segment, suggesting that these stenoses were not fixed in severity. However, the fixed plastic stenoses did not show an increase in resistance as pressure fell because the tubing was not capable of passively narrowing. Therefore, the hemodynamics of a coronary stenosis depend importantly on the type of stenosis that is present and whether it is capable of vasomotion.
High-Pressure Headaches, Low-Pressure Syndromes, and CSF Leaks: Diagnosis and Management

Background Headache resulting from idiopathic intracranial hypertension (IIH) in a population of moderately to obese women of childbearing age. The causes overall remain unclear. With this review, we provide an overview of clinical treatment and management strategies. Results IIH management is dependent on the signs and symptoms presented. Symptomatic treatment should attempt to lower intracranial pressure, reduce pain, and protect the optic nerves. Consideration for lumbar puncture and draining fluid as an option for reducing pressure may be helpful; however, repeated treatment is not usually favored by patients. Traditional prophylactic medications used in migraine may help reduce the primary headache often induced by raised intracranial pressure. We suggested surgical intervention for patients experiencing visual loss or impending visual loss and not responding to medication therapy. Conclusion In this review, we discuss headache associated with IIH and spontaneous intracranial hypotension. Much needs to be learned about treatment options for patients with cerebrospinal fluid leaks including methods to strengthen the dura.
Analysis of tumor-associated stromal cells using SCID GFP transgenic mice: contribution of local and bone marrow-derived host cells

The green fluorescence protein (GFP) from the UBI-GFP/BL6 transgenic line was bred into C57BL/6J-scid and C.B-17-scid mice for investigating host-tumor cell interactions. These mice express high levels of GFP under the control of the ubiquitin promoter in virtually all cells examined. In tumor tissue generated by implanting tumor cells in the GFP transgenic SCID mice, the tumor cells and tumor-associated murine host cells were clearly distinguished by GFP expression. A population of cells expressing the endothelial cell marker VEGFR-2/Flk-1, and the progenitor markers c-Kit and Sca-1, were incorporated into tumor tissue. The majority of the Flk-1-positive cells were hematopoietic-derived cells that coexpressed CD45. To investigate the contribution of bone marrow-derived cells to the formation of tumor vessels and stroma, tumor cells were implanted in nontransgenic SCID mice that received a bone marrow transplant from GFP-expressing SCID mice. Although GFP-positive cells were readily detected by histology in tumors taken from bone marrow transplanted animals, they were spatially isolated and lacked organization. In contrast, if tumors were implanted in nontransgenic SCID mice adjacent to a patch of transplanted GFP-expressing skin, these tumors recruited GFP-positive cells that organized into tumor vessels. The results demonstrate that hematopoietic-derived cells, including Flk-1+/CD45+ cells, readily colonized the tumor stroma but were minimally incorporated in the tumor vasculature. The majority of the tumor vessels were instead recruited from tissue adjacent to the tumor. The expression of Flk-1 on nonendothelial, tumor-associated host cells raises the possibility that VEGF antagonists, such as Avastin, could inhibit tumor growth by a mechanism involving hematopoietic-derived CD45+/Flk-1+ cells, in addition to direct suppression of endothelial cell function.
Prostate cryoablation: Update 1998†‡

Transrectal ultrasound-guided percutaneous transperineal prostate cryoablation has many attractive features both to the patient and to the urologist. The procedure typically can be done in a period of 2 hours or less on an outpatient basis with minimal blood loss and with the patient under regional or general anesthesia. With more experience in using the equipment and the techniques described, urologists can treat all stages of localized prostate cancer with relatively little morbidity. The results of this technique in the treatment of prostate cancer continue to appear promising. With follow-up of 5 years or more available in several series, cryoablation appears to be an effective modality for the eradication of localized prostate cancer, particularly low-volume cancer (PSA less than 10 ng/ml and Gleason score less than 7). Improved results, i.e., undetectable postcryoablation PSA levels and negative biopsies, may occur with modifications such as double freezing and pullback apical freezing. However, the complication rate also may increase with increased tissue destruction. To date, most complications reported have been relatively minor and require limited intervention. Notably, complications, especially incontinence, are significantly greater, in spite of successful eradication of residual tumor, in patients who undergo salvage cryoablation for recurrent disease after radiation therapy. In our experience, transrectal ultrasound-guided prostate cryoablation appears to be effective in controlling local prostate cancer in 81% of patients with minimal morbidity. As with radical prostatectomy and irradiation techniques, longer follow-up is required; however, at this time prostate cryosurgery can be considered in the following situations: as a primary treatment alternative to surgery or irradiation, as salvage treatment for recurrent cancer after irradiation, and for debulking of large symptomatic primary tumors. We look forward to the prospective randomized clinical trial comparing prostate cryoablation with external irradiation.
Adrenergic and cholinergic receptors in isolated non-pigmented ciliary epithelial cells.

Methods were developed to isolate non-pigmented ciliary epithelium from bovine eyes (BCBE) free from other cell types in the ciliary process. Once background binding due to pigment was minimized, it was possible to assay specific beta adrenergic receptors in these preparations. The BCBE beta adrenergic receptors showed appropriate stereospecificity and an order of binding affinities compatible with a beta2 adrenergic selectivity. Interestingly, specific high affinity muscarinic cholinergic receptors were detected in both BCBE and primate non-pigmented ciliary epithelium. These muscarinic receptors showed an appropriate affinity and selectivity for agonists and antagonists.Further evaluations of the receptors and responses of non-pigmented ciliary epithelial cells may prove useful in understanding the effects of adrenergic and cholinergic agents on aqueous humor inflow.
Three-dimensional z-pinch wire array modeling with ALEGRA-HEDP

An understanding of the dynamics of z-pinch wire array explosion and collapse is of critical interest to the development and future of pulsed power inertial confinement fusion experiments. Experimental results clearly show the extreme three-dimensional nature of the wire explosion and collapse process. The physics of this process can be approximated by the resistive magnetohydrodynamic (MHD) equations augmented by thermal and radiative transport modeling. Z-pinch MHD physics is dominated by material regions whose conductivity properties vary drastically as material passes from solid through melt into plasma regimes. At the same time void regions between the wires are modeled as regions of very low conductivity. This challenging physical situation requires a sophisticated three-dimensional modeling approach matched by sufficient computational resources to make progress in predictive modeling and improved physical understanding.
Comparative neuropsychology and Korsakoff's syndrome. II—Two-choice visual discrimination learning

Abstract Performance by 12 alcoholic Korsakoff patients was compared to that of 15 patients with Huntington's disease, 11 patients with Broca's aphasia, and 13 alcoholic control subjects on two types of two-choice visual discrimination problems which, in brain-damaged monkeys, successfully dissociate deficits of visual perception from those of visual associative learning. Korsakoff and Huntington patients were slow to learn individual discriminations, but eventually performed well on them. Both groups were severely, but differently, impaired on concurrent discrimination tasks in which several pairs of stimuli are presented together within each testing session. It is suggested that the Korsakoffs have a severe deficit of associative learning combined with abnormal sensitivity to interference, whereas the Huntingtons are impaired primarily in visually-based associative learning. Deficits in Korsakoff patients are related to their widespread brain damage which includes limbic-system structures and pre-frontal cortex. Huntington deficits are related to atrophy of frontal and temporal cortex, perhaps consequent to atrophy of the caudate.
Stem unit growth analysis of Linum usitatissimum (Linaceae) internode development

How overlapping nodes in shoot apical meristems become vertically separated on mature stems was investigated via analysis of spatial and temporal characteristics of growth rate fields of Linum usitatissimum stem units. Linum grown under constant environmental conditions exhibited constant spiral phyllotaxis for nodes 35-80, during which time the stem unit was delimited vertically and tangentially by the boundaries of four successive leaf primordia along the 3-, 5-, and 8-contact parastichies and radially by these boundaries extended to the centroid of the stem. Stem unit age was assessed by a stem unit plastochron index (SUPI) based on a 5 mm reference length. Growth characteristics of -32-0 SUPI stem units were investigated using cylindrical coordinates. Vertical growth velocity was uniform within stem units, increasing basipetally as the units expanded. Vertical strain rate of nodes was nonlinear and consistently lower than the linear rate of subjacent stem units. Radial and tangential stem unit velocity fields were steady and uniform up to -25 SUPI; thereafter, these fields were characterized by uniform spatial and temporal patterns. Stem unit analysis suggests that the stem is a steady-state growth structure up until -25 SUPI, but thereafter it should be viewed as a repetitive growth structure.
U4 snRNA Regulates Formation of the U6 Telestem within the U4/U6 Di-snRNA

Many of the spliceosomal small nuclear RNAs (snRNAs) undergo large-scale structural rearrangements during spliceosome assembly, activation and catalysis. This is exemplified by the highly conserved U6 snRNA which can exist in isolation in the U6 small nuclear ribonucleoprotein (snRNP); basepaired with U4 in the U4/U6 di-snRNP, U4/U6.U5 tri-snRNP, and spliceosomal B complex; or basepaired with the pre-mRNA intron and the U2 snRNA in the catalytic spliceosome. Through genetic evidence and structure probing (1, 2), it was previously proposed that the U4/U6 di-snRNA consisted of a three-helical junction core domain flanked by single stranded regions. Using single-molecule Forster resonance energy transfer (smFRET), we discovered a dynamic equilibrium between RNA conformations formed by the flanking single stranded regions. Our smFRET data is consistent with the presence of two mutually exclusive structures: (1) a U4/U6 di-snRNA containing both basepaired U4/U6 and the U6 telestem and (2) a U4/U6 di-snRNA with extended basepairing located near U4/U6 stem I. These data show that the U6 telestem persists in the U4/U6 di-snRNA and that its formation can be regulated by novel basepairing interactions with U4. This suggests conservation of mechanism between the yeast and human U4/U6 di-snRNAs. Finally, we speculate that telestem formation can be dynamically regulated by spliceosomal proteins to aid in tri-snRNP disassembly and spliceosome activation_rationalizing previous observations concerning the mechanism of the U4/U6 RNA helicase Brr2.References1.Brow, D.A., and C. Guthrie. 1988. Spliceosomal RNA U6 is remarkably conserved from yeast to mammals. Nature. 334: 213-218.2.Mougin, A., A. Gottschalk, P. Fabrizio, R. Luhrmann, and C. Branlant. 2002. Direct probing of RNA structure and RNA-protein interactions in purified HeLa cell's and yeast spliceosomal U4/U6.U5 tri-snRNP particles. Journal of Molecular Biology. 317: 631-649.
The evaporation behaviour of neptunium dioxide

Abstract The evaporation behaviour of neptunium dioxide in vacuo has been studied over the temperature range 1850–2475°K. The gaseous oxides NpO 2 and NpO were the only species observed and the temperature dependence of the major species NpO 2 was measured mass-spectrometrically. The total mass effusion rates were determined by collecting known fractions of effusate which were subsequently assayed by alpha counting of 237 Np. The effect on the partial pressures due to the variation of sample size and the fractional amount evaporated indicates that the solid dioxide becomes substoicheiometric and produces a bivariant system. The extent of substoicheiometry, although unknown, grossly affects the partial pressure of NpO(g) but has an insignificant influence on the partial pressure of NpO 2 (g). The experimental results are combined with known and estimated thermodynamic data to yield the standard free energy of formation of NpO 2 (g), ΔG f °(NpO 2 , g) = −114,000 + 3·5 T the dissociation energy of NpO 2 (g), 14·3 ± 0·3 eV, and an estimated value for the dissociation energy of NpO(g), 7·4 ± 0·3 eV.
Tumour specificity and immunological suppression.

ANTISERA toxic for tumours but innocuous for normal tissues have been sought with meagre or questionable success since the early days of immunology. The outcome of most experiments has emphasized the antigenic similarities rather than the disparities between normal and tumour cells so that the existence of tumour-specific antigens has remained entirely hypothetical. Indeed, it would seem rather hopeless to resume the search for tumour-specific antigens were it not for two circumstances. The first of these is the work of Zil'ber1,2 and others in the U.S.S.R. who by means of anaphylactic reactions in the guinea pig have provided strong evidence for the existence of tumour-specific antigens. The second is the phenomenon of immunological suppression, including acquired tolerance for homologous transplants3 and suppression of specific antibody response4 by the introduction of tissues or simple antigens into embryonic or early post-natal mammals. The present experiments were based on the assumption that if one could suppress antibody formation against normal tissues, as suggested by the work of Feldman and Yaffee5, it might be possible to produce antibodies directed exclusively against the specific antigens of tumours—providing such antigens exist. Our results thus far encourage the conclusion that the immunologically suppressed animal provides the long-sought means of producing antisera capable of discriminating between tumours and normal tissues.
Iconic memory and hypnotizability: processing speed, skill, or strategy differences?

Abstract The purported relationship between hypnotizability and speed of information transfer from iconic to short-term memory was studied in a comparison of 12 low and 12 high hypnotizable Ss. As in Ingram, Saccuzzo, McNeill, and McDonald (1979), high hypnotizable Ss showed less interference from a visual mask in the report of a briefly presented item than did low hypnotizable Ss when the mask delays were predictable. When the delay of the mask could not be anticipated, however, differences between high and low hypnotizable Ss disappeared. It is suggested that differences in information processing related to hypnotizability may be due to differences in strategy, skills, or other factors, rather than underlying information processing speed.
National estimates of mental health utilization and expenditures for children in 1998

No recent national data on expenditures and utilization are available to provide a benchmark for reform of mental health systems for children and adolescents. The most recent estimates, from 1986, predate the dramatic growth of managed care. This study provides updated national estimates. Treatment expenditures are estimated to be $11.68 billion ($172 per child). Adolescents have the highest expenditures at $293 per child followed by $163 per child aged 6 to 11 and $35 per preschoolaged child. Outpatient services account for 57%, inpatient for 33%, and psychotropic medications for 9% of the total. Unlike earlier reports, outpatient care now accounts for the majority of expenditures. This finding replicates the differences between recent managed care data and earlier actuarial databases for privately insured adults and confirms the trend from inpatient toward outpatient care.
Phased backpropagation: a hybrid of BPTT and temporal BP

We present a synthesis of backpropagation through time (BPTT) and temporal backpropagation (TB) that permits the efficiency of TB in dealing with delay lines to be combined with the generality of BPTT with respect to arbitrary discrete-time network structures. We express our formulation in terms of an ordered network, subsuming less general network architectures such as time-delay networks and recurrent multilayer perceptrons. The resulting formulation can also be combined with derivative adaptive critics, thereby providing a further unification of techniques for training dynamic networks.
Abstract 629: Sensing Nutrient Overload: The Role of the Endothelium

Recent data suggest that leukocyte accumulation into visceral fat depots occurs within 72 following high fat feeding. At this early stage, neutrophils have been found to be the predominant leukocyte population to infiltrate the visceral fat. Other studies have shown that deletion of the high affinity counter-receptor for P-selectin, P-selectin glycoprotein ligand-1 (PSGL-1), attenuate immune cell infiltration into fat depots of chronically high fat fed mice. Accordingly, we tested the hypothesis that endothelial, expressed P-selectin serves as a molecular sensor for initiating inflammatory responses in the microcirculation of the visceral fat following nutrient overload. Wild-type (WT) and P-sel-/- C57BL/6 mice were given either a low fat (10% fat) or a high fat (60% fat) meal by gavage. All mice were studied 1, 2, 3, 4 and 24 hours post gavage by intravital microscopy (IVM) to measure postprandial kinetics of leukocyte rolling (LR) and leukocyte adhesion (LA) in the microcirculation of the mesenteric fat pads. In WT mice, administration of high fat meals acutely and transiently increased LR and LA in the visceral fat microcirculation (p<0.001 vs low fat meal). In contrast, high fat meals failed to increase LR and LA in P-sel-/- mice (NS vs low fat meal WT). Immunofluorescence studies demonstrated that fat meals upregulate cell surface expression of P-selectin in the visceral fat microcirculation, but not in the subcutaneous one. Flow cytometry studies demonstrated that neutrophils are the main leukocyte population to acutely infiltrate visceral fat depots after lipid overload. Mechanistic studies were also undertaken using palmitate, a postprandially elevated, unsaturated free fatty acid. Superfusion of (dose) palmitate during IVM acutely increased LR and LA in the microcirculation of the mesenteric fat pads of WT mice (p<0.01 vs control), a response that was prevented in vivo by P-selectin antibody blockade. Taken together, these data demonstrate that endothelial P-selectin plays a key role in the early inflammatory responses to fat overload by promoting neutrophil trafficking in the microcirculation of the visceral fat. These data first uncover a novel nutrient-sensory role of the vascular endothelium, which warrants further investigation.
PHENOMENON OF LOCAL SKIN REACTIVITY TO BACTERIAL FILTRATES: AN ANTIBODY AUXILIARY TO SERUM NEUTRALIZATION OF MENINGOCOCCUS REACTING FACTORS

In. this paper there is described an antibody auxiliary to the neutralization of meningococcus reacting factors. The presence of the antibody facilitates studies on neutralizing potency of antimeningococcus sera. There is also reported a non-specific neutralizing factor of a heterologous immune serum, which can be differentiated from specific neutralizing antibodies of antimeningococcus sera. Its nature and connection with the auxiliary antibody remain to be determined.
Cotrimoxazole prophylaxis and malaria in Africa: Have the important questions been answered?

In 1999, two studies from Abidjan, Cote d’Ivoire showed that daily prophylaxis with cotrimoxazole (trimethoprimsulfamethoxazole) decreased morbidity in adults with stage 2 or 3 human immunodeficiency virus (HIV) infection 1 and reduced mortality in those co-infected with HIV and tuberculosis, 2 mainly by preventing invasive bacterial infections, chiefly non-typhoid Salmonella and pneumococcus. Malaria infections were also decreased. The opportunistic infections prevented by cotrimoxazole in developed countries, Pneumocystis jiroveci pneumonia and toxoplasmosis, were not prevented in these studies. Pressure quickly mounted to offer cotrimoxazole prophylaxis to people with HIV throughout Africa. Although some argued that the risks and benefits of cotrimoxazole prophylaxis were likely to be different in settings with different epidemiologic and drug-resistance patterns for opportunistic infections and malaria, others believed that the data from the two Abidjan trials justified stopping ongoing and planned placebo-controlled trials elsewhere in Africa. National policymakers, however, generally believed that they lacked sufficient information for sound policy decisions, and recommendations to offer cotrimoxazole prophylaxis were slow to be adopted and implemented. Most bacterial infections that were prevented in Abidjan were susceptible to cotrimoxazole. Elsewhere on the continent, most notably in eastern and southern Africa, cotrimoxazole resistance was much more prevalent among bacterial pathogens; in Malawi at that time, 83% of non-typhoid Salmonella and 91% of pneumococcus were resistant. 3 Some policymakers and technical advisors doubted that cotrimoxazole would work as well (or at all) in the face of higher rates of resistance, and worried that widespread cotrimoxazole use would impair the efficacy of sulfadoxine-pyrimethamine (SP), an antifolate antimalarial drug closely related to trimethoprim-sulfamethoxazole, for treating malaria. 3–5
A Brief History of Tissue Models For Cardiac Electrophysiology

The last four decades have produced a number of significant advances in the developments of computer models to simulate and investigate the electrical activity of cardiac tissue. The tissue descriptions that underlie these simulations have been built from a combination of clever insight and careful comparison with measured data at multiple scales. Tissue models have not only led to greater insights into the mechanisms of life-threatening arrhythmias but have been used to engineer new therapies to treat the consequences of cardiac disease. This paper is a look back at the early years in the cardiac modeling and the challenges facing the field as models move toward the clinic.
Two Variability Orders

In this paper we study a new variability order that is denoted by ≤st:icx. This order has important advantages over previous variability orders that have been introduced and studied in the literature. In particular, X ≤st:icxY implies that Var[h(X)] ≤ Var[h (Y)] for all increasing convex functions h. The new order is also closed under formations of increasing directionally convex functions; thus it follows that it is closed, in particular, under convolutions. These properties make this order useful in applications. Some sufficient conditions for X ≤st:icxY are described. For this purpose, a new order, called the excess wealth order, is introduced and studied. This new order is based on the excess wealth transform which, in turn, is related to the Lorenz curve and to the TTT (total time on test) transform. The relationships to these transforms are also studied in this paper. The main closure properties of the order ≤st:icx are derived, and some typical applications in queueing theory are described.
Quaternary volcanoes of the Lake Rudolf region: II. The lavas of North Island, South Island and the Barrier

Abstract North Island, South Island, and the Barrier are Quaternary volcanoes in the Lake Rudolf portion of the East African Rift Valley. They have produced lavas ranging in composition from olivine basalt through trachybasalt to trachyte. Magnesian olivine, diopsidic augite, and calcic plagioclase appear as phenocrysts in the more basic lavas; anorthoclase is the only phenocryst in the trachyte of the Barrier. Xenocrysts of calcic plagioclase occur in the trachyte of North Island. The groundmasses are composed of clinopyroxene, plagioclase, magnetite and/or ilmenite, and interstitial glass. The amount of potassium and iron in the plagioclase is systematically related to the anorthite content, and although the general relations are the same for feldspars from the three areas, the absolute amount of these elements is different in North Island feldspars from that of the South Island and Barrier feldspars.
Thermal Plasma Chemical Vapor Deposition of Superhard Nanostructured Si-C-N Coatings

A triple torch plasma reactor was used to synthesize Si—C—N composite films via the thermal plasma chemical vapor deposition process. The argon-nitrogen plasma provided atomic nitrogen to carbon- and silicon-based reactants, which were injected through a central injection probe and ring configuration. Films were deposited with variations of the total nitrogen flow through the torches (1.5-4.5slm), reactant mixture (silicon tetrachloride and acetylene or hexamethyldisilazane) and substrate material (silicon and molybdenum). Micro X-ray diffraction was used to determine that both α-Si 3 N 4 and β-Si 3 N 4 were dominant in most of the depositions. Composites of silicon nitride and silicon carbide were synthesized on molybdenum. The bonding of amorphous phases was investigated using Fourier transform infrared spectroscopy, which indicated the presence of N—H, CH x and CΞ in various films. Indentation tests on the polished film cross-sections determined that large variations in hardness and elastic modulus existed for minor changes in film composition. Correlations between indentation results and scanning electron and optical microscope images showed that the mechanical properties greatly depend on the film morphology; the denser, smoother, and more crystalline films tended to display enhanced mechanical properties.