cssi/SciSciGPT-SciSciNet huggingface dataset:
Decreasing uncertainties in assessing environmental exposure, risk, and ecological implications of nanomaterials.

Determining the fate and interactions of nanomaterials in complex environmental contexts is required to assess exposure and possible harm as well as to inform regulation.
Thermal-mechanical response of nearly opaque materials exposed to continuous radiation

Thermal stress distribution and temperature profiles in nearly opaque spherical shell under radiant and convective heating flux
On the computation of complex equilibria

A method is described for solving the problem: given fixed pressure, temperature, the amounts of the chemical elements, and the chemical potentials of possible chemical species at the pressure and temperature specified, determine the equilibrium composition. The method requires a minimum of judgment on the part of the user. A modification of Naphtali's method for direct minimization of Gibbs' function provides an estimate of the composition of sufficient accuracy to insure convergence of solution, by the Newton-Raphson method, of the nonlinear equations describing the equilibrium. Problems in treating multiple phaes of unknown stability and chemical species present in small amouts are handled by ignoring unstable phases and small quantitites in the direct minimization until the amounts of the major consitituents have been at least approximately determined. To accomplish this, species temporarily ignored are assigned a ficitious mol fraction so that their re-entry into the calculation can be established. Truncation errors in the direct minimziation can be tolerated because of the two-step method. Examples of some of the problems solved are given.
Estimating Thermodynamic State and Ignition in HCCI With Variable Fuel Injection Timing

Homogeneous charge compression ignition (HCCI) combustion timing depends on properties of gas in the cylinder such as temperature and composition. However, these properties are extremely difficult to measure. In this work, we present a method to estimate the thermodynamic state in order to map ignition timing for exhaust-recompression HCCI. Viability is demonstrated on four experiments. To capture the effect of fuel that is injected into recompressed combustion products, the method begins with a hypothesis of recompression reactions. From an initial guess, the method deterministically updates the chemical composition estimate in the cylinder over combustion, exhaust, recompression reactions and induction. The update function is based on incylinder pressure measurements, the ideal gas law and the first law of thermodynamics. The estimates are compared to measurements of inducted air and exhaust oxygen concentration to check the original hypothesis. Finally, the estimated thermodynamic state is correlated to combustion timing to produce a rich ignition map.Copyright © 2007 by ASME
The proton-pumping site of cytochrome c oxidase: a model of its structure and mechanism.

Cytochrome c oxidase is an electron-transfer driven proton pump. In this paper, we propose a complete chemical mechanism for the enzyme's proton-pumping site. The mechanism achieves pumping with chemical reaction steps localized at a redox center within the enzyme; no indirect coupling through protein conformational changes is required. The proposed mechanism is based on a novel redox-linked transition metal ligand substitution reaction. The use of this reaction leads in a straightforward manner to explicit mechanisms for achieving all of the processes previously determined (Blair, D.F., Gelles, J. and Chan, S.I. (1986) Biophys. J. 50, 713-733) to be needed to accomplish redox-linked proton pumping. These processes include: (1) modulation of the energetics of protonation/deprotonation reactions and modulation of the energetics of redox reactions by the structural state of the pumping site; (2) control of the rates of the pump's redox reactions with its electron-transfer partners during the turnover cycle (gating of electrons); and (3) regulation of the rates of the protonation/deprotonation reactions between the pumping site and the aqueous phases on the two sides of the membrane during the reaction cycle (gating of protons). The model is the first proposed for the cytochrome oxidase proton pump which is mechanistically complete and sufficiently specific that a realistic assessment can be made of how well the model pump would function as a redox-linked free-energy transducer. This assessment is accomplished via analyses of the thermodynamic properties and steady-state kinetics expected of the model. These analyses demonstrate that the model would function as an efficient pump and that its behavior would be very similar to that observed of cytochrome oxidase both in the mitochondrion and in purified preparations. The analysis presented here leads to the following important general conclusions regarding the mechanistic features of the oxidase proton pump. (1) A workable proton-pump mechanism does not require large protein conformational changes. (2) A redox-linked proton pump need not display a pH-dependent midpoint potential, as has frequently been assumed. (3) Mechanisms for redox-linked proton pumps that involve transition metal ligand exchange reactions are quite attractive because such reactions readily lend themselves to the linked gating processes necessary for proton pumping.
Scale normalization of histopathological images for batch invariant cancer diagnostic models

Histopathological images acquired from different experimental set-ups often suffer from batch-effects due to color variations and scale variations. In this paper, we develop a novel scale normalization model for histopathological images based on nuclear area distributions. Results indicate that the normalization model closely fits empirical values for two renal tumor datasets. We study the effect of scale normalization on classification of renal tumor images. Scale normalization improves classification performance in most cases. However, performance decreases in a few cases. In order to understand this, we propose two methods to filter extracted image features that are sensitive to image scaling and features that are uncorrelated with scaling factor. Feature filtering improves the classification performance of cases that were initially negatively affected by scale normalization.
IGFs, Insulin, Shh, bFGF, and TGF-β1 Interact Synergistically to Promote Somite Myogenesis in Vitro

Abstract Studies from our group and others have shown that in vitro somite myogenesis is regulated by neural tube and notochord factors including Wnt, Sonic hedgehog (Shh), and basic fibroblast growth factor (bFGF) together with transforming growth factor-β1 (TGF-β1). In this study we report that insulin and insulin-like growth factors I and II (IGF-I and -II) also promote myogenesis in explant cultures containing single somites or somite-sized pieces of segmental plate mesoderm from 2-day (stage 10–14) chicken embryos and that the combination of insulin/IGFs with bFGF plus TGF-β1 promotes even higher levels of myogenesis. We also found that Shh promotes myogenesis in this in vitro system and that Shh interacts synergistically with insulin/IGFs to promote high levels of myogenesis. RT-PCR analysis detected insulin, IGF-II, insulin receptor, and IGF receptor mRNAs in both the neural tube and the somites, whereas IGF-I transcripts were detected in entire embryos but not in the neural tube or somites. Treatment of somite–neural tube cocultures with anti-insulin, anti-IGF-II, anti-insulin receptor, or anti-IGF receptor blocking antibodies caused a significant decrease in myogenesis. These results are consistent with the hypothesis that systemic IGF-I as well as insulin and IGF-II secreted by the neural tube act as additional early myogenic signals during embryogenesis. Further studies indicate that insulin, IGFs, bFGF, and Shh also stimulate somite cell proliferation and influence apoptosis.
A SEM-based System for Photomask Placement Metrology

Mask metrology has long been separated into critical dimension (CD) vs. pattern placement (Registration) in terms of both the parametric definitions as well as measurement techniques applied. The combined effect of measured CD and placement errors on mask-to-mask overlay (OL) is hard to model let alone calculate in definitive terms. As device size continues to shrink, novel lithography solutions being considered for 45nm technology node and beyond such as double exposure and patterning techniques are projected to tighten the overlay requirement much faster than originally anticipated. Electron optics is generally the preferred solution for small feature size in-die sampling by virtue of its high image resolution, measurement precision, low cross-field distortion and absence of tool induced shift. In this paper we propose to examine and identify the key elements of a new approach in applying electron optics to a mask metrology system that combines CD and pattern placement. We will then present the results from our experiments with a prototype wide field scanning electron microscope (WFSEM) using reticle with optical proximity correction (OPC) features.
Histone Deacetylase 9 Activates γ-Globin Gene Expression in Primary Erythroid Cells

Strategies to induce fetal hemoglobin (HbF) synthesis for the treatment of β-hemoglobinopathies probably involve protein modifications by histone deacetylases (HDACs) that mediate γ-globin gene regulation. However, the role of individual HDACs in globin gene expression is not very well understood; thus, the focus of our study was to identify HDACs involved in γ-globin activation. K562 erythroleukemia cells treated with the HbF inducers hemin, trichostatin A, and sodium butyrate had significantly reduced mRNA levels of HDAC9 and its splice variant histone deacetylase-related protein. Subsequently, HDAC9 gene knockdown produced dose-dependent γ-globin gene silencing over an 80-320 nm range. Enforced expression with the pTarget-HDAC9 vector produced a dose-dependent 2.5-fold increase in γ-globin mRNA (p < 0.05). Furthermore, ChIP assays showed HDAC9 binding in vivo in the upstream Gγ-globin gene promoter region. To determine the physiological relevance of these findings, human primary erythroid progenitors were treated with HDAC9 siRNA; we observed 40 and 60% γ-globin gene silencing in day 11 (early) and day 28 (late) progenitors. Moreover, enforced HDAC9 expression increased γ-globin mRNA levels by 2.5-fold with a simultaneous 7-fold increase in HbF. Collectively, these data support a positive role for HDAC9 in γ-globin gene regulation.
Selectivity for harmonic structure in complex sounds by the green treefrog ( Hyla cinerea )

1. A psychophysical technique based on reflex modification was used to study the detection of two-tone complexes in background noise by the green treefrog (Hyla cinerea). Three different two-tone complexes were synthesized and presented to measure detection thresholds--a harmonic complex of 900 + 3000 Hz (periodicity of 300 Hz, mimicking the structure of the natural advertisement call); an inharmonic complex of 830 + 3100 Hz; and a second harmonic complex of 828 + 2760 Hz (periodicity of 276 Hz). 2. Masked thresholds and 'critical ratios' (signal-to-noise ratios at threshold) were lowest for the two harmonic complexes (900 + 3000 Hz, mean 'critical ratio' of 16 dB; 828 + 2760 Hz, mean 'critical ratio' of 14 dB). For the inharmonic complex, for which there is no stable first-harmonic periodicity, the mean 'critical ratio' was 24 dB. These data suggest that the green treefrog is sensitive to the harmonic structure of complex sounds as a specific acoustic feature. 3. Because of the unique structure of the treefrog's inner ear, the heightened behavioral sensitivity to harmonic complexes must be due to processing in the central, rather than peripheral, auditory system.
Reconcile Discrepancies of Current Syngas Kinetics Models by Considering Turbulence Effects on Ignition Delay at Gas-Turbine Relevant Operating Conditions

With the increasing interest in utilizing syngas in gas turbine applications, the characterization of H2/CO reaction chemistry under high-pressure and moderate-temperature operating conditions has been the focus of recent investigations. Different chemical-kinetics and hydrodynamic processes have been identified as being responsible for the discrepancies between experimental measurements and kinetic predictions of syngas ignition delay times. This paper complements previous studies, and provides insight on the role of turbulence fluctuations and small-scale mixture inhomogeneities on the syngas combustion process. To this end, an analytic model has been developed that describes the turbulence amplification and combustion in the so-called adiabatic core region of a rapid compression machine (RCM). In this formulation, enhancement of turbulence and small-scale mixture fluctuations during the RCM compression phase are modeled using rapid distortion theory. The subsequent ignition and combustion processes are described using a Lagrangian Fokker-Planck model which considers turbulence/chemistry interaction and detailed reaction chemistry. The model was applied to different syngas mixtures and operating conditions, including pressures up to 20 atm and temperatures between 600 and 1300 K. Parametric studies showed that the model captures experimentally observed trends of reduced
Recent advances in using Drosophila to model neurodegenerative diseases

Neurodegenerative diseases are progressive disorders of the nervous system that affect the function and maintenance of specific neuronal populations. Most disease cases are sporadic with no known cause. The identification of genes associated with familial cases of these diseases has enabled the development of animal models to study disease mechanisms. The model organism Drosophila has been successfully used to study pathogenic mechanisms of a wide range of neurodegenerative diseases. Recent genetic studies in the Drosophila models have provided new insights into disease mechanisms, emphasizing the roles played by mitochondrial dynamics, RNA (including miRNA) function, protein translation, and synaptic plasticity and differentiation. It is anticipated that Drosophila models will further our understanding of mechanisms of neurodegeneration and facilitate the development of novel and rational treatments for these debilitating neurodegenerative diseases.
SU‐GG‐T‐261: An Integrated Software Environment for Image Guided Adaptive Radiation Therapy Research

Purpose: Modern research in Image Guided Adaptive Radiation Therapy (IGART) generates very large quantities of imaging data, as it is no longer uncommon to collect upwards of 200GBytes of imaging data, stored as thousands of files, per research patient. Such proliferation of data requires new software infrastructure which can handle collection, anonymization, indexing and automated processing of data. Software infrastructure, in support of NIH sponsored research program on IGART, had to be developed, ab initio, at our institution. Materials and Methods: Patient data is initially collected by networked Personal Computers provided by vendors of imaging equipment. Disk synchronization software is used to create a UNIX disk mirror of data bearing disks, which is hosted on EMC Clariion networked storage devices supported by the university computing group. Automated Patient Accumulator (APA) application extracts data from the mirror, accumulates data for selected patients, and performs initial tests of data integrity. Automated Database Builder (ADB) application monitors accumulated data, creates anonymized copy of newly acquired data, and organizes anonymized data into the Reference Data Database (RDD). A customized interface to Philips Pinnacle Treatment Planning System (TPS) supports dynamic building of TPS patients from RDD images, as well as saving of image segmentation and treatment planning data back into the RDD. A dedicated C++ library, called Research Computing Framework (RCF), supports programmatic access to RDD data, building of automated data processing pipelines, and storage of derived research data into temporary research databases. Data visualization is based on the AVS Express toolkit, combined with the RCF library as means of converting research data types into AVS data types. Results: A comprehensive software infrastructure to support IGART research has been built, ab initio, at our institution. This infrastructure is currently being used to perform IGART research. Acknowledgments: Supported by NIH Grant P01 CA11602
The advantages of absorbed-dose calibration factors

A formalism for clinical external beam dosimetry based on use of ion chamber absorbed-dose calibration factors is outlined in the context and notation of the AAPM TG-21 protocol. It is shown that basing clinical dosimetry on absorbed-dose calibration factors ND leads to considerable simplification and reduced uncertainty in dose measurement. In keeping with a protocol which is used in Germany, a quantity kQ is defined which relates an absorbed-dose calibration factor in a beam of quality Q0 to that in a beam of quality Q. For 38 cylindrical ion chambers, two sets of values are presented for ND/NX and Ngas/ND and for kQ for photon beams with beam quality specified by the TPR20(10) ratio. One set is based on TG-21's protocol to allow the new formalism to be used while maintaining equivalence to the TG-21 protocol. To demonstrate the magnitude of the overall error in the TG-21 protocol, the other set uses corrected versions of the TG-21 equations and the more consistent physical data of the IAEA Code of Practice. Comparisons are made to procedures based on air-kerma or exposure calibration factors and it is shown that accuracy and simplicity are gained by avoiding the determination of Ngas from NX. It is also shown that the kQ approach simplifies the use of plastic phantoms in photon beams since kQ values change by less than 0.6% compared to those in water although an overall correction factor of 0.973 is needed to go from absorbed dose in water calibration factors to those in PMMA or polystyrene. Values of kQ calculated using the IAEA Code of Practice are presented but are shown to be anomalous because of the way the effective point of measurement changes for 60Co beams. In photon beams the major difference between the IAEA Code of Practice and the corrected AAPM TG-21 protocol is shown to be the Prepl correction factor. Calculated kQ curves and three parameter equations for them are presented for each wall material and are shown to represent accurately the kQ curve for all ion chambers in this study with a wall of that specified material and a thickness less than 0.25 g/cm2. Values of kQ can be measured using the primary standards for absorbed dose in photon beams.
P16-09. Adenovirus 5 vector HIV vaccination does not affect mucosal homing markers on Ad5-specific CD4+ T-cells in humans

Methods Ad-specific T cell responses were characterized in five seropositive and seronegative subjects from the Merck phase I 016 trial, the immediate STEP trial predecessor. Subjects received 3 × 1011 vector particles Merck Ad5 gag/pol/nef at weeks 0, 4 and 30. PBMC samples were obtained at weeks 0, 4, 8,18, 26, 30, 42, 52 and 78 relative to vaccination. T-cell responses to Ad were measured by stimulating PBMCs overnight with whole Ad vector before measuring functionality (IFN-γ, TNF-α, IL-2) memory phenotype (CD45RO, CCR7) and mucosal homing markers (α4, β7, CCR10, αE) by multicolor flow cytometry.
Low temperature aging behavior of type 308 stainless steel weld metal

Abstract The aging behavior of welded type 308 stainless steel was evaluated by mechanical property testing and microstructural examination. Aging was carried out at 475°C for up to 20,000 h. The initial material consisted of austenite with approximately 10% ferrite. Upon aging, the ferrite hardness increased up to 100%. This hardening was accompanied by a noticeable increase in the ductile—brittle transition temperature and a drop in the upper shelf energy, as measured by Charpy impact tests, and a degradation in fracture toughness, as determined by J-integral test. Tensile properties did not change significantly with aging. Microstructural analysis indicated that the ferrite decomposed spinodally into iron-rich α and chromium-enriched α′. In addition, abundant precipitation of nickel- and silicon-rich G-phase was found within the ferrite and M23C6 carbide formed along the austenite-ferrite interface. These effects are similar to the aging behavior of cast stainless steels. Occasionally, large G-phase or α precipitates were also found along the austenite-ferrite interface after aging more than 1000 h. After comparison of the mechanical property changes with the microstructural features, it was concluded that both spinodal decomposition as well as G-phase formation contribute to ferrite hardening. Spinodal decomposition results in embrittlement of the weld insofar as the ductile-brittle transition temperature is raised. G-phase formation and carbide precipitation are associated with a degradation in the ductile fracture properties, as shown by a drop in the upper shelf energy and a decrease in the fracture toughness.
Electrochemical regeneration of Fe2+ in Fenton oxidation processes.

This study is to establish optimal conditions for the minimization of iron sludge produced in Fenton oxidation processes by electro-regenerating Fe(2+) with constant potential (CPM) or constant current mode (CCM). Results indicate that the optimal cathodic potential for Fe(2+) regeneration is -0.1 V vs. the saturated calomel electrode (SCE) in terms of current efficiency. Keeping the initial Fe(3+) concentration ([Fe(3+)](0)) constant, the average current density produced at -0.1 V vs. SCE (CPM) is approximately equal to the optimal current density applied in the CCM. The suitable pH range is below the pH value determined by Fe(3+) hydrolysis. As expected, increasing cathode surface area and solution temperature notably increases Fe(2+) regeneration rate. At the optimal potential, the average current density increases linearly with [Fe(3+)](0), exhibiting a slope of 8.48 x 10(-3)(A/m(2))(mg/L)(-1). The average current efficiency varies with [Fe(3+)](0), e.g., 75% and 96-98% at 100 and > or = 500 mg/L [Fe(3+)](0), respectively. Once reaching 75% of Fe(2+) regeneration capacity, further regeneration becomes difficult due to Fe(3+) mass transfer limitation. Fe(2+) can also be effectively regenerated by dissolving iron sludge at low pH (usually </=1). The unit energy consumption is 2.0-3.0 k Wh per kg Fe(2+) regenerated.
Mechanical properties and microstructures of polycrystalline ceramic/metal superlattices: TiN/Ni and TiN/Ni0.9Cr0.1

Abstract Polycrystalline superlattice coatings of TiN/Ni and TiN/Ni 0.9 Cr 0.1 of thickness 2–3 μm were deposited onto tool steel substrates using an opposed-cathode reactive unbalanced magnetron sputtering system. The TiN/Ni superlattices have repeated periods (Λ) from 1.8 to 62 nm with various Ni layer thickness (l Ni ) to Λ ratios, l Ni /Λ. TiN/Ni 0.9 Cr 0.1 superlattices have Λ =1.2–7.4 nm with l NiCr / Λ =0.3. The structures were analyzed by X-ray diffraction, as well as plan-view and cross-sectional transmission electron microscopy. The hardnesses and elastic moduli of the superlattices were measured using nanoindentation techniques. An increase in hardness with decreasing Λ and grain size was observed. A maximum hardness of 3500 kgf mm −2 for TiN/Ni, about 1.5 times of the rule-of-mixtures values, was found at l Ni / Λ =0.16 and Λ =2.2 nm. For TiN/Ni 0.9 Cr 0.1 , a maximum hardness of 3200 kgf mm −2 was found at l Ni / gL =0.3 and Λ =1.2 nm. No significant variations in TiN/Ni 0.9 Cr 0.1 film modulus were found as a function of Λ.
Acute disposition of neck injuries.

Neck injuries can be some of the most serious and anxietyproducing injuries that occur during sporting events. It is important for the team physician to be prepared for the care of these injuries and be able to identify some of the more serious injuries. Proper care of these injuries can be life saving and prevent further injury and permanent disability. This article reviews the principles of management and latest evidence for acute neck injuries.
Creep of polycrystalline aluminium as determined from strain rate tests

Abstract Polycrystalline samples of high purity aluminium have been tested in a strain rate machine over a wide temperature range. The relationship which exists between the maximum stress, strain rate, and temperature is strain rate = A ( stress ) 4.4 exp ( — Q RT ) where A is a constant, R is the gas constant, T is the absolute temperature, Q is an activation energy equal to 36,000 cal/mole. The results are compared with those of Servi and Grant on constant stress creep tests and shown to be almost identical.
A Comparative Study of the Digestive Tracts of Caprella Equilibra Say and Cyamus Boopis Lütken (Amphipoda, Caprellidea)

[L'appareil digestif de Caprella equilibra et de Cyamus boopis a ete etudie et compare a celui d'un gammaride. L'appareil digestif de C. equilibra ressemble a celui d'un gammaride sauf sur les points suivants: absence de la glande posterieure, caecum dorsal anterieur reduit qui est double au lieu d'etre simple, presence d'une petite protuberance anterieure des glandes digestives, absence d'une arete pylorique subventrale et des plis pyloriques posterieurs. Le parasitisme des cyamides a amene des modifications nombreuses de l'anatomie de l'appareil digestif qu'on ne trouve pas chez les gammarides et les caprellides. L'estomac du cyamide n'est plus divise nettement en region pylorique et en region cardiaque. Les epines et les plis sont bien differents et l'arete pylorique a, semble-t-il, perdu sa fonction de filtration. Les glandes digestives, par deux, forment des circonvolutions et elles entrent dans l'intestin moyen plus posterieurement que celles des gammarides et des caprellides., L'appareil digestif de Caprella equilibra et de Cyamus boopis a ete etudie et compare a celui d'un gammaride. L'appareil digestif de C. equilibra ressemble a celui d'un gammaride sauf sur les points suivants: absence de la glande posterieure, caecum dorsal anterieur reduit qui est double au lieu d'etre simple, presence d'une petite protuberance anterieure des glandes digestives, absence d'une arete pylorique subventrale et des plis pyloriques posterieurs. Le parasitisme des cyamides a amene des modifications nombreuses de l'anatomie de l'appareil digestif qu'on ne trouve pas chez les gammarides et les caprellides. L'estomac du cyamide n'est plus divise nettement en region pylorique et en region cardiaque. Les epines et les plis sont bien differents et l'arete pylorique a, semble-t-il, perdu sa fonction de filtration. Les glandes digestives, par deux, forment des circonvolutions et elles entrent dans l'intestin moyen plus posterieurement que celles des gammarides et des caprellides.]
Success of using saline flush for repositioning peripherally inserted central catheters

Purpose To evaluate a peripherally inserted central venous catheter (PICC) repositioning protocol involving use of vigorous saline flush technique for correction of malpositioned PICCs placed at bedside. Materials and Methods All episodes of PICC tip malposition on post-bedside placement CXR over a 12 month period were reviewed. Data were prospectively collected at time of repositioning flush technique. Our protocol for malpositioned PICC begins with fluoroscopic evaluation of the PICC. If the PICC is too long or short or if it is coiled within an arm vein, saline flush is not attempted. Otherwise, if malposition is confirmed, vigorous saline flush technique using a 3mL polycarbonate syringe is performed under fluoroscopic guidance. If unsuccessful, the patient is then prepped and an attempt is made to exchange the PICC over a wire. Results 94 patients were included. In 5 (5%) there was spontaneous repositioning of the catheter without need for intervention. In 25 other encounters, flush repositioning was not attempted. Of the remaining 64, 30 (47%) were successfully repositioned with saline flush (Table). In the successful cases, the mean number of flushes required to reposition the PICC was 3 (SD 2, range 1-6). Out of all of the catheters, 46 (including those PICCs that were not attempted to be flushed and those that failed flush) were successfully replaced over a wire, 8 required a new venous puncture, 3 were left as midline catheters due to inability to thread the catheter centrally and 2 were pulled back and secured with a box clamp because they were too long. Mean fluoroscopy time for successful repositioning using flush technique (0.8 minutes SD 1.0) was significantly less than for those requiring wire manipulation (4.1 minutes, SD 5.3) (p Conclusion Vigorous saline flush technique is effective for correction of roughly half of selected malpositioned PICCs. It can reduce patient radiation exposure. It is most likely to be successful if the PICC is not coiled and if the tip is in the ipsilateral internal jugular vein. Table 1
Novel actions of thyroid hormone: the role of triiodothyronine in cardiac transplantation.

In clinical heart transplantation, the heart is procured from brain dead (BD) organ donors who acutely experienced a variety of critical illnesses. In all of these conditions, a profound derangemen...
A method for preparation of etched collagen fibers that support neurite outgrowth

Use of collagenous substrates for growth of attachment-dependent and attachment-independent cells have been reported in the literature. Growth of fibroblasts and epithelial cells on collagen sponges and fibers has been previously studied in our laboratory. This article reports the result of studies of neurite outgrowth on etched collagen fibers in cell culture. Collagen fibers with a mean diameter of about 134 μm were etched on glass coverslips using a collagenase solution until individual fibrils of 1 μm in diameter were observed. The kinetics of etching were optimized at a calcium chloride concentration of 5 mM and a collagenase activity of 300 unit/mL. At room temperature an etching time of 10 h maximized the number of fibrils exposed per fiber. Cell culture studies on etched collagen fibers indicate that neurites from rat fetal cortical neurons elongate along the longitudinal axes of collagen fibrils. In some instances the cell body observed was not on top of the collagen fibrils but situated between two parallel fibrils. Results of these experiments indicate that growth of neurites along collagen fibrils in cell culture may be a useful model to evaluate neurite extension in the presence of neurotrophic factors as well as to study optimization of substrates for nerve regeneration.
Representing hydrodynamically important blocking features in coastal or riverine lidar topography

Abstract. New automated methods are developed for identifying narrow landscape features that cause hydrodynamic blocking and might have critical impacts for management models of river flooding, coastal inundation, climate change, or extreme event analysis. Lidar data processed into a fine-resolution raster (1 m × 1 m) can resolve narrow blocking features in topography but typically cannot be directly used for hydrodynamic modeling. For practical applications such data are abstracted to larger scales, which can result in a loss of hydrodynamic blocking effects. The traditional approach to resolving hydrodynamic blocking features is to represent them as cell boundaries within a customized unstructured grid that is tuned to the spatial features. A new automated edge-blocking approach is developed, which allows application of an arbitrarily structured (Cartesian) mesh at coarser scales and provides contiguous representation of blocking features along Cartesian cell boundaries. This approach distorts the shape of a blocking feature (i.e., making it rectilinear along grid cell faces) but retains its critical hydrodynamic blocking height characteristics and spatial continuity within the topographic model.
Thrombin‐induced Proteolysis of Human Antithrombin III: an Outstanding Contribution of Heparin

Products obtained in reaction of excess antithrombin III (AT III) with human alpha-thrombin and heparin were found to contain markedly less of residual AT III than products of similar reactions without heparin. The increased utilization of AT III was primarily due to limited proteolysis of a portion of unbound inhibitor, associated with the release of a 50 000-dalton protein fragment. Thrombin-induced release of this fragment was promoted by polydispersed heparin preparation and, to a variable degree, by all heparin fractions obtained in gel filtration. The optimum amount of heparin required to facilitate AT III proteolysis was of 5 microgram/ml (0.8 u/ml). Excessive reduction of the residual inhibitory activity and changes in two-dimensional immunoelectrophoresis suggested that AT III in plasma is also subjected to nonproductive proteolysis and formation of a modified AT III derivative following addition of thrombin and heparin. These data indicate that the effect of heparin on AT III is more complex than generally recognized. On the one hand, heparin interacting with AT III and thrombin contributes to a rapid binding and neutralization of the enzyme; on the other, heparin facilitates proteolytic degradation of unbound inhibitor even in the presence of small quantities of thrombin accounting for excessive reduction of the overall inhibitory potential of AT III.
Induction of melanized cells from a goldfish erythrophoroma: isolation of pigment translocation variants

Melanization was induced in some cells of a goldfish tumor cell line (GEM-81) by cultivating the cells in autologous serum. The melanized cells continued to proliferate in vitro and several clones were isolated that differed with respect to cell morphology and intracellular distribution of pigment. Some of the clones consisted of cells able to translocate their melanosomes in response to epinephrine, melatonin, or adenosine 3', 5'-monophosphate.
Presentation, treatment, and outcome of oral cavity cancer: A national cancer data base report

Background Oral cancer has been identified as a significant public health threat. Systematic evaluation of the impact of this disease on the US population is of great importance to health care providers and policy makers. Methods This study used the National Cancer Data Base (NCDB) to evaluate associations between demographic and disease characteristics, treatment, and survival for patients with oral cavity cancer in the United States. Of patients diagnosed between 1985 and 1996, 58,976 were extracted from the NCDB. ANOVAs were performed on selected cross-tabulations, and relative survival was used to calculate outcome. Results Median age of patients was 64.0 years. Men made up 60.2% of patients. Pathologic diagnosis was squamous cell carcinoma (SCC) in 86.3% of cases. Younger patients had a much higher frequency of non-SCC, and this was related to survival in these patients. African-Americans (independent of income), lower income patients, and patients with higher grade disease were seen more frequently with advanced-stage SCC. Five-year relative survival for SCC cases was lower for older patients, men, and African-Americans. Conclusions This study addressed many issues related to oral cancer that have been previously discussed in the literature. The demographic, site, stage, histologic, and survival data available for this large number of cases in the NCDB allowed an accurate characterization of the contemporary status of oral cancer in the United States. © 2002 John Wiley & Sons, Inc.
Theory of Spectral Asymmetries and Nonlinear Currents in the Equatorial Electrojet

The spectral up-down asymmetry of type 1 echoes returned from the equatorial electrojet irregularities is shown to be a consequence of the nonlinear development of the horizontally propagating large scale primary waves which dominate the k spectrum of the electrojet turbulence. The waves reduce the vertical electric polarization field of the electrojet and suffer second harmonic distortion as they grow. These effects together could cause an asymmetry exceeding 20% between the upward and downward components of the relative (to the ions) electron velocity associated with the primary waves. This asymmetry, which changes its direction from day to night as does the horizontal electrojet current, could easily account for the radar observations. The modification of the vertical polarization field also limits the perturbed vertical electron velocity to a value about the same as the mean horizontal electron velocity, which should explain why type 1 echoes are observed in all directions only when the mean electron velocity is supersonic. Finally, this modification of the polarization field amounts to a significant reduction in the electrojet conductivity, an effect which should be included in electrojet models.
Detection Of Antibody-Antigen Reactions At A Glass-Liquid Interface: A Novel Fibre-Optic Sensor Concept

The reaction of antibody molecules immobilized onto the sur-face of fused silica fibre optic or planar waveguides with antigens in solution was detected by interaction with the evanescent wave. By detecting in-line fluorescence, the measurement of human IgG is described.
A determinantal lower bound

Abstract There are many known upper bounds for | det (·)|, the modulus of the determinant function, but useful lower bounds are rare. We show that if l and u are positive lower and upper bounds on the moduli of the eigenvalues of a real or complex invertible n×n matrix A such that | tr (A)|⩾nl , then | det (A)|⩾l κ u n−κ , where κ=κ(l,u)=[(nu−| tr (A)|)/(u−l)] . Since κ⩽n , our lower bound improves the obvious lower bound l n . In two cases the trace inequality is automatically satisfied. If A is a diagonally dominant real matrix with positive diagonal entries, then one can easily compute l and u using Gerschgorin's circle theorem. While if A is positive definite Hermitian with eigenvalues λ 1 ⩽λ 2 ⩽⋯⩽λ n , then our bound implies the inequality det (A)⩾λ 1 κ λ n n−κ , where κ=κ(λ 1 ,λ n ). Lower bounds like those established here have proved useful in obtaining new formulas for the approximation of π , e , square roots of numbers, and more generally real or complex roots of arbitrary polynomials.
Oxyluminescence of fatty natural substances

A number of fatty substances, covering a range from low to high degree of unsaturation, have been observed to emit light when heated. Relative intensities of light emitted at 200C are compared to degree of unsaturation. Activation energies were calculated for those samples giving approximately straight line plots of logG vs. 1/T, whereG is galvanometer deflection andT is the absolute temperature.
Intake, digestibility, and nitrogen retention by sheep supplemented with warm-season legume haylages or soybean meal

The increasing cost of feed supplements necessitates evaluation of alternatives for ruminant livestock grazing poor quality warm-season grasses. This study determined how supplementing bahiagrass hay (Paspalum notatum Flugge cv. Pensacola) with soybean [Glycine max (L.) Merr.] meal or warm-season legume hays affected intake, digestibility, and N utilization by lambs. Dorper x Katadhin crossbred lambs (30.6 +/- 5.5 kg; n = 42) were fed bahiagrass hay (73.8% NDF, 8.1% CP) for ad libitum intake and supplemented with nothing (control), soybean meal, or hays of annual peanut [Arachis hypogaea (L.) cv. Florida MDR98; 46.2% NDF, 14.7% CP], cowpea [Vigna unguiculata (L.) Walp. cv. Iron clay; 62.2% NDF, 11.7% CP], perennial peanut (Arachis glabrata Benth. cv. Florigraze; 43.3% NDF, 15.2% CP), pigeonpea [Cajanus cajan (L.) Millsp. cv. GA-2; 78.6% NDF, 12.2% CP], or soybean (cv. Pioneer 97B52; 59.0% NDF, 13.5% CP). Legume hays were supplemented at 50% of total diet DM, and soybean meal was supplemented at a level (4.25% of diet DM) that matched the average dietary CP content (10.8%) of the legume hay-supplemented diets. The cowpea, pigeonpea, and soybean were harvested at respective maturities that maximized DM yield and nutritive value, and the peanuts were first cuttings. Diets were fed to 6 lambs per treatment for 2 consecutive 21-d periods. Supplementation with hays of annual and perennial peanut, cowpea, and soybean increased (P < 0.01) DMI vs. control, but apparent DM digestibility was only increased (P = 0.03) by supplementation with annual or perennial peanut hay. Compared with the control, N intake, digestibility, and retention were increased (P < 0.01) by supplementation with legume hay or soybean meal. Responses were greatest when annual or perennial peanut hays were fed. Ruminal ammonia concentration was increased (P < 0.01) by all legume hay supplements vs. the control. Microbial N synthesis and ruminally degraded OM were increased (P = 0.03) by perennial and annual peanut hay supplementation, but efficiency of microbial synthesis was not different (P = 0.52) among diets. Unlike other supplements, annual and perennial peanut hays increased DM and N intake and digestibility and improved microbial N synthesis; therefore, they were the best supplements for the bahiagrass hay under the conditions of this study.
Economic Causes of Late Nineteenth-Century Agrarian Unrest: Comment

In a recent paper in this JOURNAL, Robert A. McGuire has revised and extended the view that "the amount of uncertainty (risk) in agriculture was a major factor in fomenting agrarian unrest. ' By measuring the relative variability of prices, incomes, and yields using time series data from the period 1866-1909, McGuire has found that the states with the highest relative variability had, in general, the highest levels of agrarian protest.2 Since McGuire's view is that relative (as opposed to absolute) variability, of prices and incomes especially, and of yields to a lesser extent, was an important determinant of the location of farm protest, he used as his measure the Random Variability Coefficient (RVC), expressed as a percentage and defined as
Kinetics of protease hydrolysis of extended peptide substrates: measurement by flow-injection analysis.

Abstract A flow-injection analysis (FIA) system was developed to study the enzyme-catalyzed hydrolysis of synthetic peptides, each of which contained one scissile bond. The concentrations of α-amino groups in reactions mixtures were determined by FIA with o -phthalaldehyde as a fluorescence reagent. The method allows a rapid, precise, and sensitive determination of kinetic constants for proteases acting on extended peptide substrates.
The cycad neurotoxic amino acid, ß-N-methylamino-l-alanine (BMAA), elevates intracellular calcium levels in dissociated rat brain cells

Abstract Seeds of the Guam cycad Cycas micronesica K.D. Hill (Cycadaceae), which contain s-methylamino- l -alanine (BMAA), have been implicated in the etiology of the devastating neurodisease ALS–PDC that is found among the native Chamorros on Guam. The disease also occurs in the native populations on Irian Jaya and the Kii Peninsula of Japan, and in all three areas the cycad seeds are used either dietarily or medically. ALS–PDC is a complex of amyotrophic lateral sclerosis and parkinsonism dementia complex with additional symptoms of Alzheimer's. It is well known that Ca 2+ elevations in brain cells can lead to cell death and neurodiseases. Therefore, we evaluated the ability of the cycad toxin BMAA to elevate the intracellular calcium concentration ([Ca 2+ ] i ) in dissociated newborn rat brain cells loaded with fura-2 dye. BMAA produced an increase in intracellular calcium levels in a concentration-dependent manner. The increases were dependent not only on extracellular calcium concentrations, but also significantly on the presence of bicarbonate ion. Increasing concentrations of sodium bicarbonate resulted in a potentiation of the BMAA-induced [Ca 2+ ] i elevation. The bicarbonate dependence did not result from the increased sodium concentration or alkalinization of the buffer. Our results support the hypothesis that the neurotoxicity of BMAA is due to an excitotoxic mechanism, involving elevated intracellular calcium levels and bicarbonate. Furthermore, since BMAA alone produced no increase in Ca 2+ levels, these results suggest the involvement of a product of BMAA and CO 2 , namely a β-carbamate, which has a structure similar to other excitatory amino acids (EAA) such as glutamate; thus, the causative agent for ALS–PDC on Guam and elsewhere may be the β-carbamate of BMAA. These findings support the theory that some forms of other neurodiseases may also involve environmental toxins.
Auditor's Guide to M&A Scandals

Companies have grown ever larger by regularly consolidating and acquiring other businesses, in an effort to compete globally. The author of this article, a veteran financial investigator, has worked for the FBI, a New Jersey county prosecutor's office, and others. He says that the countervailing force of antitrust enforcement too often plays second fiddle or is passive in the face of freewheeling, deregulated merger and acquisition (M&A) activity. In this article, he reveals some of the detrimental by-products of M&A, including the increased risk of corruption. He also discusses the auditor's role in detecting—and preventing—these adverse M&A by-products and risks. © 2013 Wiley Periodicals, Inc.
Theory & Methods: On Estimators of Scale and Dispersion in Neighbourhoods ofParametric Families

This paper investigates two estimators under the non-parametric neighbourhoods of an exponential scale parametric family. It uses the relative efficiency approach and shows that the tighter lower bounds on the relative efficiency of the upper trimmed mean to mean can be obtained under a sufficient condition. This condition gives the relationship between the possible positive lower bound and the degree of asymmetry of some related distributions. Similar arguments can be applied to the comparison of dispersion estimators under the neighbourhoods of a normal distribution.
A generalized Markov Chain modeling approach for on board applications

This paper deals with a new class of Markov Chain type models that can be effectively used for real time modeling and on-line learning of nonlinear systems with uncertainties. We expand the concept of the generalized Markov Chain - a probabilistic model that synergistically combines the idea of transition probabilities with the information granulation paradigm. We consider generalized Markov chains based on two different types of information granules - intervals and fuzzy subsets - and the methods for their learning from data. We also analyze the relationship between the Markov chains and the fuzzy models and derive an alternative formulation of the Chapman-Kolmogorov equation that applies to stochastic models in fuzzy environment. As this approach is motivated by and intended for in-vehicle applications, results are illustrated on examples of granular models of vehicle speed and road grade.
Mechanism Design for Single Leader Stackelberg Problems and Application to Procurement Auction Design

In this paper, we focus on mechanism design for single leader Stackelberg problems, which are a special case of hierarchical decision making problems in which a distinguished agent, known as the leader, makes the first move and this action is followed by the actions of the remaining agents, which are known as the followers. These problems are also known as single leader rest follower (SLRF) problems. There are many examples of such problems in the areas of electronic commerce, supply chain management, manufacturing systems, distributed computing, transportation networks, and multiagent systems. The game induced among the agents for these problems is a Bayesian Stackelberg game, which is more general than a Bayesian game. For this reason, classical mechanism design, which is based on Bayesian games, cannot be applied as is for solving SLRF mechanism design problems. In this paper, we extend classical mechanism design theory to the specific setting of SLRF problems. As a significant application of the theory developed, we explore two examples from the domain of electronic commerce-first-price and second-price electronic procurement auctions with reserve prices. Using an SLRF model for these auctions, we derive certain key results using the SLRF mechanism design framework developed in this paper. The theory developed has many promising applications in modeling and solving emerging game theoretic problems in engineering.