cssi/SciSciGPT-SciSciNet huggingface dataset:
Chylous Effusions Revisited

Varying terms and criteria have been used in the veterinary literature to characterize milky opaque pleural effusions through the years. This article addresses ideas widely repeated in the veterinary and human literature upon which time, experience, diagnostic techniques, experimental data, and improved understanding of pathogenesis have cast doubt. Topics discussed include terminology, pathogenesis of chylous and pseudochylous effusions, criteria for differentiation of chylous from pseudochylous effusions, and clinicopathologic changes associated with drainage of chylous effusions.
Component-ontological representation of function for reasoning about devices

Abstract We propose principles behind component-ontological representation of function. In this representation, the function of a component is expressed in terms of its ports. The representation has many advantages: (i) The function of a component can be represented in isolation of its environment. Therefore, libraries of function models can be built. These models are re-usable. (ii) The function model of a complex device can be built by composing the function models of its components. This helps preserve the fidelity of representation. Further, this process can be automated. (iii) The representation is linear in space complexity: the function model of an atomic component is linear in the number of its ports, and that of a composite device is in most cases linear in the number of its components. We propose Classes as a component-ontological representation of function. We illustrate Classes by using it to model parts of a printer buffer, which has the complexity of a microcomputer. We also demonstrate how class models may be used for model-based diagnosis.
Simulation of blood bank systems

This paper examines the use of simulations to develop decision procedures for the management of individual hospital blood banks and central blood bank systems. Due to the perishability of blood products and the stochastic nature of both the demand and supply processes, such multi-product, multiechelon systems can only be analyzed effectively by simulation. The hospital and central bank model structures are reviewed, as are the input, output, and validation analysis procedures. A number of issues relevant to the application of simulation to health care systems analysis are raised by the development and application of these models. Of particular interest is the integration of the simulations into a recursive statistics-optimization-simulation approach to systems analysis.
Cell biology: regulated self-cannibalism.

Cells consume parts of themselves to survive starvation and during development. But how do they control this process of self-eating so that it begins at the right time and does not end up killing the cell?
Diffusivity in the Nb-Al binary solid solution

Abstract Binary diffusion in the Nb-Al b.c.c. solid solution was studied in the temperature range 1350–1550 °C using the diffusion couple technique. The interdiffusion coefficient values varied linearly with composition in the composition range 1–3 at.% Al and showed Arrhenius behavior as a function of temperature. The average activation energy was determined to be 80 kcal mol −1 with a frequency factor of 11 × 10 −2 cm 2 s −1 .
Simultaneous-source full-wavefield inversion

Seismic data acquired for exploration, development or production surveys are typically densely sampled, often driven by high-resolution imaging objectives. It is common to have tens or hundreds of thousands of shots in a marine survey. This poses a significant computational challenge for full-wavefield inversion (FWI), because each shot needs to be simulated individually. Even with the fastest computing systems, the cost increases tremendously while incorporating complex physics and inverting higher frequencies in the data. For example, the cost of 3D finite-difference elastic simulation is roughly 50 times the cost of acoustic simulation. And it increases by a factor of 16 if the frequency of the simulation is doubled. For 3D acoustic wavefield simulation, the cost is 256 times higher at 40 Hz than at 10 Hz. Therefore, large-scale 3D application of FWI is a challenging problem. The method involves several forward modeling and gradient computations of each field gather by numerically solving the wave equation. Even in a large computer environment, for an average seismic survey, the turnaround time for FWI can be significant. Furthermore, most FWI applications require several trial runs to choose suitable parameters to tune the inversion for a stable solution. The key to making FWI practical is to reduce the number of individual shots, thereby providing computational savings for both forward modeling and gradient computations.
Plasma factor XIII binds specifically to fibrinogen molecules containing gamma chains.

The difference between peak 1 and peak 2 fibrinogen lies in their γ chains. Peak 1 molecules contain 2 γA chains; peak 2 molecules contain 1 γA and 1 γ‘ chain, the latter of which contains a 20 amino acid extension (γ‘ 408−427) replacing the carboxyl-terminal 4 amino acids of the γA chain (γA 408−411). While the existence of γ‘ chains in plasma fibrinogen molecules has been known for many years, their function remains unknown. When fibrinogen is purified from plasma, the factor XIII zymogen (A2B2) copurifies with it and is found only in the peak 2 fibrinogen when this fraction is separated from peak 1 fibrinogen by ion-exchange chromatography on DEAE-cellulose. Factor XIII alone applied to the same DEAE column elutes at a position between peak 1 and peak 2. When mixtures of peak 1 fibrinogen plus factor XIII or peak 2 fibrinogen plus factor XIII are applied to DEAE columns, the peak 1/factor XIII mixture elutes in two peaks, whereas the peak 2/factor XIII mixture elutes in the peak 2 fibrinogen position. ...
Vascular reactivity in hypertension: Altered effect of ouabain

Ouabain inhibits the relaxing effect of Ca2+ (but not of Mn2+) on contractile responses in tail artery strips isolated from spontaneously hypertensive and normotensive rats. The magnitude of ouabain inhibition was greater in vascular strips from hypertensive rats suggesting a significant difference in basic membrane function in hypertensive vascular smooth muscle.
Inhibition of NAD(P)H oxidase potentiates AT2 receptor agonist-induced natriuresis in Sprague-Dawley rats.

A positive association between renin-angiotensin system, especially AT1 receptor, and oxidative stress in the pathogenesis of hypertension and cardiovascular/renal diseases has been suggested. Howe...
Rawls, the difference principle, and economic inequality

Rawls’s theory of justice has been criticized for allowing individuals by their own voluntary choice to make themselves members of the ‘least advantaged’ class and thereby eligible, albeit undeservedly, for the benefits mandated by the Difference Principle. I argue, first, that this criticism overlooks the fact that the Difference Principle applies only to the lifetime expectations of representative persons and, second, that it is possible to implement the Difference Principle (and the social minimum) through policies that do not create work disincentives or require making objectionable moral judgments about who is and who is not deserving of assistance.
Comparison of Macedon and Darwin glass

Abstract Chemical analyses are presented for major and minor elements in two specimens of natural glass reported from Macedon, Victoria, and are compared with new analyses of glass from Mt. Darwin, Tasmania. One specimen of Macedon glass is dark, the other light; both are spongy with relatively large cavities of size uncommon in Darwin glass. Some of the new analyses of Darwin glass extend considerably the compositional range previously reported for Mg, Ni and Co. The chemical composition of Macedon glass cannot be distinguished from that of Darwin glass for any of twenty-five elements investigated. It appears possible that the two specimens of glass reported from Macedon may represent either two mislabelled pieces of Darwin glass, or else a separate natural occurrence of Darwin glass 560 km north of Mt. Darwin.
Candida parapsilosis fungemia in burn patients: report of three cases

Three patients with Candida parapsilosis septicemia, secondary to large burns, are reported. All patients sustained large burns with inhalation injuries and were treated with various topical antibiotics. All had sepsis with various bacterial organisms and had received treatment with systemic antibiotics prior to the development of the Candida episode. Once a positive blood culture for Candida parapsilosis was obtained, treatment was carried out with amphotericin-B. Sensitivity data indicated that this was the appropriate systemic agent. All patients recovered uneventfully after a 10-day course of amphotericin-B therapy.
A new look at the BCF surface diffusion model

Abstract The BCF surface diffusion growth rate is shown to be given by G = GWFF(λ0/2λs), where GWF is the Wilson-Frenkel li miting growth rate for a rough crystal. F(λ0/2λs) ⩽ 1 is a correction term accounting for the increased evaporation. Consequently the non-linear to linear growth transition exhibited by the BCF equation is attributed to surface roughening.
Onset and end of the summer melt season over sea ice: thermal structure and surface energy perspective from SHEBA

Various measurements from the Surface Heat Flux of the Arctic Ocean (SHEBA) experiment have been combined to study structures and processes producing the onset and end of summer melt over Arctic sea ice. The analysis links the surface energy budget to free-troposphere synoptic variables, clouds, precipitation, and in-ice temperatures. The key results are (1) SHEBA melt-season transitions are associated with atmospheric synoptic events (2) onset of melt clearly occurs on May 28, while the end of melt is produced by a sequence of three atmospheric storm events over a 28-day period producing step-like reductions in the net surface energy flux. The last one occurs on August 22.; (3) melt onset is primarily due to large increases in the downwelling longwave radiation and modest decreases in the surface albedo; (4) decreases in the downwelling longwave radiation occur for all end-of-melt transition steps, while increases in surface albedo occur for the first two; (5) decreases in downwelling shortwave radiation contribute only to the first end-of-melt transition step; (6) springtime free-tropospheric warming preconditions the atmosphere–ice system for the subsequent melt onset; and (7) melt-season transitions also mark transitions in system responses to radiative energy flux changes because of invariant melt-season surface temperatures. The extensive SHEBA observations enable an understanding of the complex processes not available from other field program data. The analysis provides a basis for future testing of the generality of the results, and contributes to better physical understanding of multi-year analyses of melt-season trends from less extensive data sets.
Hsp47 and Cyclophilin B Traverse the Endoplasmic Reticulum with Procollagen into Pre-Golgi Intermediate Vesicles A ROLE FOR Hsp47 AND CYCLOPHILIN B IN THE EXPORT OF PROCOLLAGEN FROM THE ENDOPLASMIC RETICULUM

Hsp47 and cyclophilin B (CyPB) are residents of the endoplasmic reticulum (ER). Both of these proteins are closely associated with polysome-associated α1(I) procollagen chains. Hsp47 possesses chaperone properties early during the translation of procollagen while the cis/trans-isomerase properties of CyPB facilitate procollagen folding. In this report, we further investigate the interaction of these proteins with procollagen I during export from the ER. To inhibit vesicular budding and retain procollagen within the ER, cells were treated with the heterotrimeric G protein inhibitor mastoparan or calphostin C, a specific inhibitor of diacylglycerol/phorbol ester binding proteins. To arrest procollagen in pre-Golgi intermediate vesicles, cells were treated with guanosine 5ʹ-3-O-(thio)triphosphate. Pulse-chase experiments of cells labeled with [35S]methionine followed by immunoprecipitation during the chase period with anti-procollagen, anti-Hsp47, and anti-CyPB antibodies were performed to reveal the relationship between Hsp47/CyPB/procollagen I. The distribution of procollagen, Hsp47, and CyPB to the ER and/or pre-Golgi vesicles was verified by immunofluorescence. Hsp47 and CyPB remained associated with procollagen retained within the ER. Hsp47 and CyPB were also associated with procollagen exported from the ER into pre-Golgi intermediate vesicles. Treatment of cells with cyclosporin A diminished the levels of CyPB bound to procollagen and diminished the rate of Hsp47 released from procollagen and the rate of procollagen secretion, suggesting that Hsp47 release from procollagen may be driven by helix formation. Also, these studies suggest that Hsp47 may resemble protein disulfide isomerase and possess both chaperone and anti-chaperone properties. During translation, high levels of Hsp47 are seen to limit protein aggregation and facilitate chain registration. Later, Hsp47 and/or CyPB and protein disulfide isomerase act as anti-chaperones and provide the basis for concentration of procollagen for ER export.
Treatment of the syndromic midface: a long-term assessment at skeletal maturity.

Background Midfacial advancements improve function and normalize appearance in growing children with syndromic craniosynostosis yet carry substantial risks while often offering only transient benefits. The authors sought to evaluate outcomes and the number of advancements required, at skeletal maturity. Methods The authors performed a retrospective review of all children undergoing rigid external distraction Le Fort III advancement who had reached skeletal maturity, including examinations, photographic scoring, and cephalometric, anthropometric and polysomnography data. Results Over 15 years, 104 children underwent distraction and 32 met skeletal maturity criterion (mean age, 18.6 years). Thirty-four percent had prior conventional Le Fort III advancement (mean age, 5.6 years), primarily by other surgeons. Primary distractions were performed on average at 9.1 years. Ten children presented with obstructive sleep apnea; eight normalized, two improved, but 30 percent subsequently developed recurrent apnea. Per anthropometry, no sagittal growth was noted after a Le Fort III. With a mean follow-up of 9.4 years, almost half (15 of 32) underwent two midfacial advancements; however, following primary distractions, only 25 percent required repeated advancements. Associated with repeated procedures were a greater degree of midfacial hypoplasia (-2.4 versus -1.6, p = 0.01), advancement at a younger age (7.1 versus 9.5 years, p = 0.04), and failure to overcorrect midfacial position (p = 0.03). Conclusions These data suggest that sagittal midfacial growth ceases after advancement. Operation before 8 years old and failure to overadvance the midface were both associated with need for subsequent midfacial procedures. Although distraction effectively eliminated apnea, subsequent ventilatory degradation may occur, suggesting the need for continued surveillance.
Reactive Nitrogen Species Switch on Early Extracellular Matrix Remodeling via Induction of MMP1 and TNFα

Background & Aims Liver injury leads to generation of reactive oxygen and nitrogen species, which can react to produce peroxynitrite (ONOO − ). We investigated whether ONOO − and its metabolites modulate extracellular matrix remodeling. Methods Stellate cells (HSC) were incubated with pure ONOO − or SIN-1 (a ONOO − donor). Western blot, nuclear in vitro transcription, Northern blot, qPCR, and promoter transactivation analysis for COL1A1 and COL1A2 were carried out. Rats were fed alcohol or injected with CCl 4 to cause alcohol-induced liver injury and an early fibrogenic response. Results HSC incubated with ONOO − or SIN-1 showed similar viability, proliferation, COL1A1 and COL1A2 transcription rates, and mRNA levels as controls. There was a time- and dose-dependent down-regulation of collagen I and α-Sma proteins and up-regulation of MMP1 and TNFα, indicating decreased HSC activation. These effects were blocked by ONOO − scavengers. SIN-1 or ONOO − increased nitrosylation of MMP1/MMP13 and transactivation of the MMP1 , MMP13 , and TNFα promoters. A TNFα neutralizing antibody or GSH-ethyl ester blocked MMP1 promoter transactivation; whereas TNFα or l-buthionine sulfoximine, which depletes GSH, further enhanced it. Pretreatment with SIN-1 or ONOO − reduced the TGFβ pro-fibrogenic response in HSC. In vivo experiments validated the protective role of ONOO − on the early fibrogenic response. However, highly activated HSC, such as myofibroblasts and HSC from chronic alcohol-fed rats, were resistant to the anti-fibrogenic actions of ONOO − due to higher levels of GSH, a ONOO − scavenger, overproduction of pro-fibrogenic TGFβ, and reactive oxygen species. Conclusion ONOO − could induce a protective mechanism in HSC in early stages of liver injury.
Growth modes of Ag deposited on Si(111) with simultaneous low energy ion bombardment

The influence of simultaneous low-energy argon ion bombardment on the nucleation and growth of sputter-deposited silver on p-doped Si(111) under ultra-high vacuum conditions has been investigated using Auger electron spectroscopy in conjunction with proton-induced X-ray emission (PIXE). Argon ion energies used were 0.5, 1.0, and 1.5 keV with the ratio of ion arrival rate to silver atom arrival rate ranging from 0.14 to 0.5. The intensities of the SiLVV and AgLVV Auger transitions were measured as a function of total deposition time. Proton-induced X-ray emission was used to measure the thickness (areal density) of the deposited silver as a function of deposition time, allowing the growth mode of the film to be determined by plotting the ratio of AgLVV/SiLVV Auger intensities as a function of film thickness. For the case of deposition without ion beam activation, results were consistent with a Stranski-Krastanov, or layer-plus-island growth mode. At elevated temperature (420 ° C), the same growth mode was observed, but with substantially lower fractional silver island coverage. For simultaneous ion bombardment with 0.5 and 1.0 keV Ar+, a change to layer-by-layer growth was observed to occur at 4.5 and 6 equivalent monolayers, respectively, for ion-to-atom arrival ratios greater than 0.34. This phenomenon is likely due to sputter redeposition and ion enhanced nucleation site formation.
Theoretical Response from a Magnetic-Wire Record

This paper considers the effect of magnetic properties of a record wire on the output level and frequency response of a magnetic recording system. The amount of magnetic energy that can be stored at each wavelength determines the voltage output to be expected from a given translating head. Frequency response for a typical record wire is calculated according to derived relations, and compared with experimental data.
Impact strength and elongation-to-break of compatibilized ternary blends of polypropylene, nylon 66, and polystyrene

The Izod impact strength and tensile elongation-to-break were measured for blends of nylon 66 and polystyrene in a polypropylene matrix with and without compatibilization by an ionomer resin (for nylon 66) and a styrene-block-ethylene-co-butylene-block-styrene copolymer (for polystyrene). With 20% nylon 66 and 20% polystyrene, about 5% of each compatibilizer was optimal. When used together for the ternary blend, there seemed to be little gross interference (or synergism) between the compatibilizers. A comparison between binary blends suggests that what interaction does exists may be synergistic. Polym. Eng. Sci. 44:1800–1809, 2004. © 2004 Society of Plastics Engineers.
Effect of Ag on the surface barrier for depletion of oxygen from polycrystalline YBa2Cu3O7 oxides.

We have investigated the effect of evaporated Ag on the depletion of oxygen from polycrystalline $\mathrm{Y}{\mathrm{Ba}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}$ in a He ambient atmosphere by in situ resistivity experiments and surface spectroscopies. Our data indicate an increase in the rate of out-diffusion of oxygen due to the presence of the Ag, which lowers the surface barrier for the out-diffusion of oxygen by 0.2\ifmmode\pm\else\textpm\fi{}0.03 eV. We have performed x-ray photoelectron spectroscopy (XPS) analysis of the in situ fractured surfaces to indicate the presence of Ag at the internal surfaces in the oxide. XPS data from Ag-free in situ scraped samples show oxygen accumulation in the near-surface region upon vacuum annealing. This effect is prevented by evaporation of a few monolayers of Ag. Changes in the cutoff energies of the ultraviolet photoelectron spectra indicate that a submonolayer coverage of Ag is sufficient to produce a change in the work function of 0.3 eV, corresponding to the lowering of the surface barrier.
Application of phase unwrapping to image restoration

Abstract The restoration of phase information in two image processing problems is studied. First, two methods due to Knox and McGlamery for obtaining diffraction limited phase information of objects viewed through randomly fluctuating media are improved and evaluated on computer-simulated data. Although both methods yield good results it is concluded that Knox's algorithm is superior. Second, two techniques for acquiring the phase of a blur function given only the degraded image are evaluated. An existing method is improved and a new method is introduced. Experimental results indicate that these algorithms are sensitive to both the image class and edge effects.
POLLEN PORE DEVELOPMENT AND ITS SPATIAL ORIENTATION DURING MICROSPOROGENESIS IN THE GRASS SORGHUM BICOLOR

During development the microspores and pollen grains form depressions in the tapetal orbicular wall, the microspore pore being tightly appressed to the tapetum until maturity
The Negro, Urbanization, and Relative Deprivation in the Deep South

The central hypothesis of this paper is that as the Negro in the deep South becomes more urban, he becomes less equal to the white population around him in terms of education, occupation, and income. The concept of relative deprivation is used in this regard to examine the position in which the Negro finds himself in relation to whites who live in the same general area. The data obtained from the 1960 United States Census tend to support the hypothesis. Although the urban Negro in the deep South ranks higher than his rural counterpart on any absolute educational, occupational, or economic scale, the discrepancy between Negro and white in these variables is higher in urban areas.
Improving Phosphorus Use Efficiency Through Potato Rhizosphere Modification and Extension

Phosphorus (P) fertilization is essential for societal sustainability. However, plant P uptake is inefficient due to poor soil P solubility, especially for the potato (Solanum tuberosum L.) plant due to its relatively poor rooting efficiency. Phosphorus use efficiency (PUE) can be increased with rhizosphere modifications such as: (1) raising the bulk pH of acid soils, (2) placement of fertilizer in the rhizosphere by broadcast incorporation and/or, especially, as a concentrated band, (3) use of slow and controlled release P fertilizers, (4) use of organic acids to increase P solubility in alkaline soils, (5) use of an acid polymer, and (6) extending the effective rhizosphere zone via any practice that fosters root growth, such as through promotion of mycorrhizal development. Alone or in combination, these techniques offer an opportunity to increase PUE.
Long‐term ozone exposure affects winter hardiness of red spruce (Picea rubens Sarg.) seedlings

SUMMARY Red spruce (Picea rubens Sarg.) seedlings were exposed to elevated levels of ozone during a growing season and into the period of early winter frosts. Samples were taken for histological analysis, chlorophyll content, and carotenoid content. Ozone treatments increased mesophyll cell disruption after frosts in early winter. Cell injury increased with increasing ozone concentrations up to 2 × ambient. In the spring, injury was assayed by ranking trees based on overall appearance and by counting the number of shoots with brown needles. Ozone treatments had no effect on winter injury as scored by the ranking method. There was also no effect on the number of injured flushes when all trees were considered. However, when only those trees exhibiting winter injury were considered, there was a small, but statistically significant effect of ozone on the number of injured shoots. Thus, there is evidence that ozone increases injury from freezing temperatures in the autumn. Ozone slightly increases browning in the spring in sensitive trees. There were no correlations between histological injury in the autumn and appearance in the spring, indicating that there may be different aspects of the winter injury syndrome.
Flat adenomas in the National Polyp Study: is there increased risk for high-grade dysplasia initially or during surveillance?

Background & Aims : The flat adenoma may be a more aggressive pathway in colorectal carcinogenesis. Sessile adenomas from the National Polyp Study cohort were reclassified histopathologically as flat or polypoid and compared with initial and surveillance pathology. Methods : A total of 933 sessile adenomas detected during 1980–1990 were reclassified as follows: (1) adenoma thickness (AT): ≤1.3 mm, and (2) adenoma ratio (AR): adenoma thickness Results : The analysis encompassed 8401 person-years of follow-up evaluation. AT and AR measures of adenoma flatness were 95% concordant. By the AT measure, flat adenomas (n = 474) represented 27% of all baseline adenomas. Flat adenomas were found to be no more likely to exhibit high-grade dysplasia than sessile (polypoid) or pedunculated adenomas, the odds ratio for high-grade dysplasia was 1.91 (95% confidence interval [CI], 0.66–5.47; P = 0.23) for sessile (polypoid) vs. flat adenomas and 1.78 (95% CI, 0.63–5.02; P = 0.28) for pedunculated vs. flat adenomas adjusted for size, villous component, and location, and corrected for correlation of risk within an individual patient. Patients with flat adenomas at initial colonoscopy were not at greater risk for advanced adenomas at surveillance compared with those with polypoid adenomas only, the odds ratio was 0.76 (95% CI, 0.4–1.42; P = .39), adjusted for multiplicity, age, and family history of colorectal cancer. Conclusions : Flat adenomas identified in the National Polyp Study cohort at baseline were not associated with a higher risk for high-grade dysplasia initially, or for advanced adenomas at surveillance.
Store Image as a Predictor of Store Patronage for Nonprescription Medication Purchases: A Multiattribute Model Approach

ABSTRACTFactors affecting patronage for prescription medication purchases have been extensively studied by researchers over the past three decades. In contrast, limited attention, if any, has been given to examining patronage motives for purchase of nonprescription medications. This study used a multiattribute model approach to assess consumers' images of three store types (food stores, mass-merchandise stores, and pharmacies) as sources of nonprescription medications. Multiple regression analysis was used to evaluate the importance of store image in attracting consumers (patronage) to competing store types. The study sample consisted of 500 randomly selected households from the Indianapolis metropolitan statistical area (MSA). A usable response rate of 49% was obtained. Pharmacies had a significantly higher mean store image score (356) than mass-merchandise stores (280) and food stores (261). The percentage of nonprescription medication purchases made in the three store types varied significantly based o...
Contamination of commercial preparations of xanthine oxidase by a Ca2+-dependent phospholipase A2.

Abstract Using [1- 14 C]oleate-labelled autoclaved Escherichia coli as substrate, we demonstrate that many, but not all, commercial preparations of xanthine oxidase contain phospholipase A 2 activity as a contaminant. Phospholipase A 2 activity (64.3–545.6 nmol phospholipid hydrolyzed per min per mg protein) was optimal in the neutral to alkaline pH range, was Ca 2+ -dependent, and was unaffected by the addition of xanthine. Phospholipase A 2 activity was totally inhibited by 1.0 mM EDTA while radical production by xanthine plus xanthine oxidase was unaffected by EDTA. Even chromatographically purified xanthine oxidase (Sigma Grade III) contained substantial phospholipase A 2 activity (64.3 nmol/min per mg). Since the preparation of xanthine oxidase employs proteolytic digestion of milk or buttermilk by pancreatin, an extract of pancreas which is an organ rich in phospholipase A 2 activity, we speculate that the contaminant phospholipase A 2 is introduced by this treatment. Because xanthine oxidase is used extensively to study free radical-induced cell injury and membrane phospholipid alterations, the presence of a potent extracellular phospholipase A 2 may have influenced previously published reports and such studies in the future should be interpreted with care.
Amniotic fluid urea nitrogen in the prediction of respiratory distress syndrome.

Amniotic fluid urea nitrogen levels can be used to predict the neonate not at risk for the development of respiratory distress syndrome. A prospective study of 110 pregnancies compared amniotic fluid urea nitrogen concentrations with the lecithin /sphingomyelin ratio and presence of phosphatidylglycerol. After determination of gestational age, amniotic fluid was analyzed for urea nitrogen concentration and an aliquot was sent to the hospital's commercial laboratory for lecithin /sphingomyelin and phosphatidylglycerol measurement. An amniotic fluid urea nitrogen level
Co–evolution of Industry Structure, Technology and Supporting Institutions, and the Making of Comparative Advantage

In recent years,a considerable body of research has been established on the co–evolution of technology and industry structure, from the time that the technology is young to the time when it is mature· A somewhat smaller body of research has been established on how private and public institutions, and public programs and policies co-evolved with a technology and industry· It is proposed here that nations differ in their pace and pattern of institutional response to the birth and development of an industry, and that the locus of comparative advantage is largely determined by these different kinds of national response.
Readers' Theater: A Process of Developing Fourth-Graders' Reading Fluency.

This study examines the process of fluency development of three fourth-grade readers of varying reading abilities. Participants were selected based on the number of words they read correctly per minute (WCPM) on the Qualitative Reading Inventory and their score on the Multidimensional Fluency Scale (MFS). Students participated in an 8-week intervention using readers' theater for fluency instruction and practice. Both qualitative and quantitative methods were used. Students were observed during the literacy block of the school day, interviewed three times each, and provided weekly student self-reports. WCPM and MFS scores were recorded weekly. Findings showed inconsistent accuracy scores but documented the progress of students' development in two of the four MFS categories: pace and expression/volume. Motivation and confidence also increased through use of readers' theater.
Frequency–energy plots of steady-state solutions for forced and damped systems, and vibration isolation by nonlinear mode localization

Abstract We study the structure of the periodic steady-state solutions of forced and damped strongly nonlinear coupled oscillators in the frequency–energy domain by constructing forced and damped frequency – energy plots (FEPs). Specifically, we analyze the steady periodic responses of a two degree-of-freedom system consisting of a grounded forced linear damped oscillator weakly coupled to a strongly nonlinear attachment under condition of 1:1 resonance. By performing complexification/averaging analysis we develop analytical approximations for strongly nonlinear steady-state responses. As an application, we examine vibration isolation of a harmonically forced linear oscillator by transferring and confining the steady-state vibration energy to the weakly coupled strongly nonlinear attachment, thereby drastically reducing its steady-state response. By comparing the nonlinear steady-state response of the linear oscillator to its corresponding frequency response function in the absence of a nonlinear attachment we demonstrate the efficacy of drastic vibration reduction through steady-state nonlinear targeted energy transfer. Hence, our study has practical implications for the effective passive vibration isolation of forced oscillators.
Note on the Erdos - Szekeres Theorem

Let g(n) denote the least integer such that among any g(n) points in general position in the plane there are always n in convex position. In 1935, P. Erdős and G. Szekeres showed that g(n) exists and $2^{n-2}+1\le g(n)\le {2n-4\choose n-2}+1$ . Recently, the upper bound has been slightly improved by Chung and Graham and by Kleitman and Pachter. In this paper we further improve the upper bound to $$g(n)\le {2n-5\choose n-2}+2.$$ 26 June, 1998 Editors-in-Chief: la href=../edboard.html#chiefslJacob E. Goodman, Richard Pollackl/al 19n3p457.pdf yes no no yes
The independent role of cyclic flexure in the early in vitro development of an engineered heart valve tissue

Tissue engineered heart valves (TEHV) are being investigated as an alternative to current non-viable prosthetic valves and valved conduits. Studies suggest that pulse duplicator bioreactors can stimulate TEHV development. In the current study, a model system was used to determine if cyclic flexure, a major mode of heart valve deformation, has independent effects on TEHV cell and extracellular matrix (ECM) development. Ovine vascular smooth muscle cells (SMC) were seeded for 30 h onto strips of non-woven 50:50 polyglycolic acid (PGA) and poly-l-lactic acid (PLLA) scaffold. After 4 days of incubation, SMC-seeded and unseeded scaffolds were either maintained under static conditions (static group), or subjected to unidirectional cyclic three-point flexure at a physiological frequency and amplitude in a bioreactor (flex group) for 3 weeks. After seeding or incubation, the effective stiffness (E) was measured, with SMC-seeded scaffolds further characterized by DNA, collagen, sulfated glycosaminoglycan (S-GAG), and elastin content, as well as by histology. The seeding period was over 90% efficient, with a significant accumulation of S-GAG, no significant change in E, and no collagen detected. Following 3 weeks of incubation, unseeded scaffolds exhibited no significant change in E in the flex or static groups. In contrast, E of SMC-seeded scaffolds increased 429% in the flex group (p<0.01) and 351% in the static group (p<0.01), with a trend of increased E, a 63% increase in collagen (p<0.05), increased vimentin expression, and a more homogenous transmural cell distribution in the flex versus static group. Moreover, a positive linear relationship (r2=0.996) was found between the mean E and mean collagen concentration. These results show that cyclic flexure can have independent effects on TEHV cell and ECM development, and may be useful in predicting the mechanical properties of TEHV constructed using novel scaffold materials.
Relationships between fungal and bacterial substrate-induced respiration, biomass and plant residue decomposition

Abstract Residues of six plant species were incubated in the field and analyzed for decomposition rates, fungal, bacterial and total substrate-induced respiration (SIR), total fungal and bacterial biomass and changes in residue composition during 161 days. Plant residues included crimson clover ( Trifolium incarnatum L.), hairy vetch ( Vicia villosa Roth), crabgrass [ Digitaria sanguinalis , (L.) Scop.], winter rye ( Secale cereale L.), grain sorghum ( Sorghum bicolor L. Moench) and chestnut oak ( Quercus prinus L.) leaves. Plant residues were incubated in litterbags placed on the soil surface in no-tillage ( T. incarnatum, V. villosa, S. bicolor, S. cereale ), old-field ( D. sanguinalis ) or hardwood forest ( Q. prinus ) plots at the Horseshoe Bend Experimental Area in Athens, Ga and collected periodically for analyses. Decomposition rate constants ( k ) were greatest for V. villosa followed by T. incarnatum, D. sanguinalis, S. cereale, S. bicolor and Q. prinus . Net N loss generally followed the pattern of dry matter loss. Net N gain was observed after 100 days of decay for those residues with high initial C:N ratios. Initial N concentration was exponentially related with the annual decay rale constant ( r 2 = 0.93) for all species; however, on an individual species basis, lignin content was best correlated to dry matter weight loss. Total SIR was greatest on T. incarnatum and V. villosa followed by D. sanguinalis, S. bicolor, S. cereale and Q. prinus . Across all sample dates, residue carbon-to-nitrogen ratio was the best predictor of total SIR. Measurements of potential fungal and bacterial activity by SIR as well as biomass-C estimates by direct counts indicated that fungi were the dominant decomposers of these surface residues. For most residues, lignin content through time exerted the greatest influence on fungal SIR and fungal biomass-C ( r = −0.56 to −0.93). Total SIR, fungal SIR and total fungal biomass tended to decrease through time as residues decomposed. Total SIR, on any given sample date, was significantly correlated with residue dry weight remaining and annual decay rate constants were exponentially related to overall mean values of total SIR for all residues excluding S. cereale ( r 2 = 0.99). Residue SIR rates as a measure of the potentially active microbial biomass reflected the resource qualities of the plant residues investigated here and were positively correlated to their decomposition rates.
Biochemistry of Cyclooxygenase (COX)-2 Inhibitors and Molecular Pathology of COX-2 in Neoplasia

Several types of human tumors overexpress cyclooxygenase (COX) -2 but not COX-1, and gene knockout transfection experiments demonstrate a central role of COX-2 in experimental tumorigenesis. COX-2 produces prostaglandins that inhibit apoptosis and stimulate angiogenesis and invasiveness. Selective COX-2 inhibitors reduce prostaglandin synthesis, restore apoptosis, and inhibit cancer cell proliferation. In animal studies they limit carcinogen-induced tumorigenesis. In contrast, aspirin-like nonselective NSAIDs such as sulindac and indomethacin inhibit not only the enzymatic action of the highly inducible, proinflammatory COX-2 but the constitutively expressed, cytoprotective COX-1 as well. Consequently, nonselective NSAIDs can cause platelet dysfunction, gastrointestinal ulceration, and kidney damage. For that reason, selective inhibition of COX-2 to treat neoplastic proliferation is preferable to nonselective inhibition. Selective COX-2 inhibitors, such as meloxicam, celecoxib (SC-58635), and rofecoxib (MK-0966), are NSAIDs that have been modified chemically to preferentially inhibit COX-2 but not COX-1. For instance, meloxicam inhibits the growth of cultured colon cancer cells (HCA-7 and Moser-S) that express COX-2 but has no effect on HCT-116 tumor cells that do not express COX-2. NS-398 induces apoptosis in COX-2 expressing LNCaP prostate cancer cells and, surprisingly, in colon cancer S/KS cells that does not express COX-2. This effect may due to induction of apoptosis through uncoupling of oxidative phosphorylation and down-regulation of Bcl-2, as has been demonstrated for some nonselective NSAIDs, for instance, flurbiprofen. COX-2 mRNA and COX-2 protein is constitutively expressed in the kidney, brain, spinal cord, and ductus deferens, and in the uterus during implantation. In addition, COX-2 is constitutively and dominantly expressed in the pancreatic islet cells. These findings might somewhat limit the use of presently available selective COX-2 inhibitors in cancer prevention but will probably not deter their successful application for the treatment of human cancers.
Three‐dimensional modelling and sequence stratigraphy of a carbonate ramp‐to‐shelf transition, Permian Upper San Andres Formation

This study highlights three-dimensional variability of stratigraphic geometries in the ramp crest to basin of mixed carbonate–siliciclastic clinoforms in the Permian San Andres Formation. Standard field techniques and mapping using ground-based lidar reveal a high degree of architectural complexity in channellized, scoured and mounded outer ramp stratigraphy. Development of these features was a function of location along the ramp profile and fluctuations in relative sea-level. Deposition of coarse-grained and fine-grained turbidites in the distal outer ramp occurred through dilute and high-density turbidity flows and was the result of highstand carbonate shedding within individual cycles. In this setting, high-frequency cycles of relative sea-level are interpreted on the basis of turbidite frequency, lateral extent and composition. Submarine siliciclastic sediment bypass during lowstand cycles resulted in variable degrees of siliciclastic preservation. Abundant siliciclastic material is preserved in the basin and distal outer ramp as point-sourced lowstand wedges and line-sourced early transgressive blankets. In mounded topography of the outer ramp, siliciclastic preservation is minimal to absent, and rare incised channels offer the best opportunity for recognition of a sequence boundary. Growth of mounded topography in the outer ramp began with scouring, followed by a combination of bioherm construction, fusulinid mound construction and isopachous draping. Intermound areas were then filled with sediment and continued mound growth was prevented by an accommodation limit. Mound growth was independent of high-frequency cycles in relative sea-level but was dependent on available accommodation dictated by low-frequency cyclicity. Low-angle ramp clinoforms with mounded topography in the outer ramp developed during the transgressive part of a composite sequence. Mound growth terminated as the ramp transformed into a shelf with oblique clinoform geometries during the highstand of the composite sequence. This example represents a ramp-to-shelf transition that is the result of forcing by relative sea-level fluctuations rather than ecologic or tectonic controls.
A survey of changes in the proportions of ambulatory training in internal medicine clerkships and residencies from 1986-87 to 1996-97.

Purpose To determine changes from 1986-87 to 1996-97 in the proportions of time devoted to education in ambulatory settings within clerkships and internal medicine residencies. Method In 1997, a questionnaire was sent to the departments of internal medicine of all 125 U.S. medical schools. The response rate was 73%. Results Training in ambulatory settings increased greatly over the decade. The percentages of time in ambulatory settings increased for clerkships from 6% to 28%, and for residencies from 14% to 30%. In 1986-87, two thirds of clerkships provided no ambulatory training; by 1996-97, only 5% were exclusively inpatient. In 1986-87, 56% of residencies devoted 10% or less of their time to ambulatory education. By 1996-97, no residency program was in this category, while 87% devoted at least 20% of their time to ambulatory training. All programs used hospital clinics for ambulatory education; more than half used private physicians' offices, while fewer used health centers, home care services, and HMOs. Problems in expanding ambulatory training included inadequate numbers of sites or patient volumes (58% of programs), insufficient instructors (55%), and costs. Conclusion There has been a major increase in the proportions of time devoted to ambulatory education in clerkships and residencies. Significant problems impede the reported desire of program directors further to increase these proportions.
Submarine geothermal resources

Approximately 20% of the earth's heat loss (or 2 × 1012 cal/s) is released through 1% of the earth's surface area and takes the form of hydrothermal discharge from young (Pleistocene or younger) rocks adjacent to active seafloor-spreading centers and submarine volcanic areas. This amount is roughly equivalent to man's present gross energy consumption rate. A sub-seafloor geothermal reservoir, to be exploitable under future economic conditions, will have to be hot, porous, permeable, large, shallow, and near an energy-deficient, populated land mass. Furthermore, the energy must be recoverable using technology achievable at a competitive cost and numerous environmental, legal and institutional problems will have to be overcome. The highest-temperature reservoirs should be found adjacent to the zones of the seafloor extension or volcanism that are subject to high sedimentation rates. The relatively impermeable sediments reduce hydrothermal-discharge flow rates, forcing the heat to be either conducted away or released by high-temperature fluids, both of which lead to reservoir temperatures that can exceed 300°C. There is evidence that the oceanic crust is quite permeable and porous and that it was amenable to deep (3–5 km) penetration by seawater at least some time in the early stages of its evolution. Most of the heat escapes far from land, but there are notable exceptions. For example, in parts of the Gulf of California, thermal gradients in the bottom sediments exceed 1°C/m. In the coastal areas of the Gulf of California, where electricity and fresh water are at a premium, this potential resource lies in shallow water (< 200 m) and within sight of land. Other interesting areas include the Sea of Japan, the Sea of Okhotsk and the Andaman Sea along the margins of the western Pacific, the Tyrrhenian Sea west of Italy, and the southern California borderland and west flank of the Juan de Fuca Ridge off the west coast of the United States. Many questions remain to be answered about the physical and other characteristics of these systems before they can be considered a viable resource. Until several of the most promising areas are carefully defined and drilled, the problem will remain unresolved.
Stochastic Game Formulation for Cognitive Radio Networks

In this paper, we model the various wireless users in a cognitive radio network as a collection of selfish, autonomous agents that strategically interact in order to compete for the dynamically available spectrum opportunities. We propose a stochastic game framework to model how the competition among users for spectrum opportunities evolves over time. At each stage of the dynamic resource allocation, a spectrum moderator auctions the available resources and the users strategically bid for the required resources. Based on the observed resource allocation and corresponding rewards from previous allocations, we propose a best response learning algorithm that can be deployed by wireless users to improve their bidding policy at each stage. The simulation results show that by deploying the proposed best response learning algorithm, the wireless users can significantly improve their own performance in terms of both the packet loss rate and the incurred cost for the used resources.
Prior familiarity, perceived bias, and one-sided versus two-sided communications☆

Abstract The persuasive effects of one-sided versus two-sided communications were retested in a nonwestern cultural setting. Perceived bias in the communication was hypothesized to account for the differential effects of the two styles of arguments. The impact of prior familiarity with the issue on the persuasive effects of the communication was examined. Subjects were 273 high-school students in Taiwan. Among the initially unfavorable, the one-sided arguments were found more effective when the subjects were not familiar with the issue, while the two-sided arguments were found more effective when the subjects were familiar with the issue. No such interaction appeared among the initially favorable. Regardless of the style of argument or initial attitudes, the effects of communication were an inverse function of detection of bias. When detection of bias was held constant, the interactive effects of the one-sided and two-sided communications all disappeared.