cssi/SciSciGPT-SciSciNet huggingface dataset:
Cobalt(II)-substituted class III alcohol and sorbitol dehydrogenases from human liver.

The catalytic zinc atoms in class III (chi) alcohol dehydrogenase (ADH) and sorbitol dehydrogenase (SDH) from human liver have been specifically removed and replaced by cobalt(II) with a new ultrafiltration technique. The electronic absorption spectrum of class III cobalt ADH (epsiolon 638 = 870 M-1 cm-1) is nearly identical with those of active site substituted horse EE and human class I (beta 1 beta 1) cobalt ADH. Thus, the coordination environment of the catalytic metal is strictly conserved in these enzymes. However, significant differences are noted when the spectra of class III ADH-coenzyme complexes are compared to the corresponding spectra of the horse enzyme. The spectrum of class III ADH.NADH is split into three bands, centered at 680, 638, and 562 nm. The class III ADH.NAD+ species resembles the alkaline form of the corresponding horse enzyme complex but without exhibiting the pH dependence of the latter. These spectral changes underscore the role of the coenzymes in differentially fine tuning the catalytic metal for its particular function in each ADH. The noncatalytic zinc of class III ADH exchanges with cobalt at pH 7.0. While 9 residues out of 15 in the loop surrounding the noncatalytic zinc of class III ADH differ from those of the class I ADH, the electronic absorption spectra of cobalt in the noncatalytic metal site of class III ADH establish that the coordination environment of this site is conserved as well. The spectrum of cobalt SDH differs significantly from those of cobalt ADHs.(ABSTRACT TRUNCATED AT 250 WORDS)
Alkali Control for Gas Turbines by a Combined Hot Gas Clean-Up Approach

Gas turbines require very clean fuels if they are to avoid high temperature corrosion due to alkali sulfates and chlorides. Indications are that the alkali (sodium and potassium) salt levels need to be well below parts per million by volume in the hot gases and probably no more than 50 parts per billion by volume (0.01 mg/m3 ) for maintenance free operation. Moreover, it is the alkali that is the dominant factor and the actual concentrations of sulfur or chlorine are of minor relevance. Recently, numerous studies have shown that by using inexpensive absorbent type clay materials such as kaolin, bentonite, emathlite, or even bauxite and boehmite that these can reduce the alkali content very significantly (≥ 90%) in the hot gases. Coupled now to a final polishing method to remove the remainder, a new viable two step approach appears technically and economically feasible. This polishing method involves adding traces of either ammonium paramolybdate or ammonium metatungstate, both of which are water soluble, as a dilute aerosol into the hot gases. The ratio of molybdenum, or tungsten, to alkali needs to be in a ratio of about two to one on an atomic basis. This modifies the deposition process and alkali polymolybdate or polytungstate bronzes are preferentially produced. These are low melting point molecules that are benign and create with any remaining alkali a protective coating on the blades. They are thermodynamically more stable and rank above the sulfates and chlorides for formation. Also, being added in quantities of only parts per million or less there are no repercussions on NOX emissions or performance and remain cost effective at these levels. This coupling of the two complimentary approaches now appears feasible for final developmental testing to permit the use of alternate fuels without a need for cool-down cleaning cycles.Copyright © 2009 by ASME
Nebulized lidocaine administered to infants and children undergoing flexible bronchoscopy

Study objectives The purpose of this study was to evaluate the safety and efficacy of nebulized lidocaine hydrochloride as a topical anesthetic for use during flexible bronchoscopy in infants and children. Design This was a prospective, randomized, double-blind study. Patients Twenty consecutive patients scheduled for flexible bronchoscopy who were not intubated and had no known cardiac or hepatic disease comprised the study group. Interventions The patients were randomized to receive either 8 mg/kg or 4 mg/kg of nebulized 2% lidocaine by face mask prior to bronchoscopy. Setting The study took place in a bronchoscopy suite at an academic medical center. Measurements To determine systemic absorption, serum lidocaine levels were obtained. To assess efficacy of nebulized lidocaine as a topical anesthetic, changes in heart rate and blood pressure were recorded, and the bronchoscopist (who did not know the lidocaine dose used) rated the ease of passage of the bronchoscope through nose, vocal cords, trachea, bronchi, and all sites overall, and the degree of cough. Results Nebulized lidocaine was safe, was well-tolerated, and provided adequate anesthesia for half of the patients. The serum lidocaine levels were much lower than the levels in the toxic range. There was a trend toward easier passage of the bronchoscope in the high-dose group at all sites noted previously that were evaluated. Conclusion Nebulized lidocaine in doses up to 8 mg/kg appears to be safe and moderately effective as a topical anesthetic for flexible bronchoscopy in infants and children. The serum levels were remarkably low. Fifty percent of the subjects required no supplemental lidocaine.
Hydrogen Bonding Lowers Intrinsic Nucleophilicity of Solvated Nucleophiles

The relationship between nucleophilicity and the structure/environment of the nucleophile is of fundamental importance in organic chemistry. In this work, we have measured nucleophilicities of a series of substituted alkoxides in the gas phase. The functional group substitutions affect the nucleophiles through ion−dipole, ion-induced dipole interactions and through hydrogen bonding whenever structurally possible. This set of alkoxides serves as an ideal model system for studying nucleophiles under microsolvation settings. Marcus theory was applied to analyze the results. Using Marcus theory, we separate nucleophilicity into two independent components, an intrinsic nucleophilicity and a thermodynamic driving force determined solely by the overall reaction exothermicity. It is found that the apparent nucleophilicities of the substituted alkoxides are always much lower than those of the unsubstituted ones. However, ion−dipole, ion-induced dipole interactions, by themselves, do not significantly affect the in...
Attosecond transient absorption probing of electronic superpositions of bound states in neon. Detection of quantum beats

Electronic wavepackets composed of multiple bound excited states of atomic neon lying between 19.6 and 21.5 eV are launched using an isolated attosecond pulse. Individual quantum beats of the wavepacket are detected by perturbing the induced polarization of the medium with a time-delayed few-femtosecond near-infrared (NIR) pulse via coupling the individual states to multiple neighboring levels. All of the initially excited states are monitored simultaneously in the attosecond transient absorption spectrum, revealing Lorentzian to Fano lineshape spectral changes as well as quantum beats. The most prominent beating of the several that were observed was in the spin–orbit split 3d absorption features, which has a 40 femtosecond period that corresponds to the spin–orbit splitting of 0.1 eV. The few-level models and multilevel calculations confirm that the observed magnitude of oscillation depends strongly on the spectral bandwidth and tuning of the NIR pulse and on the location of possible coupling states.
Energy Partition to the Workpiece for Grinding of Ceramics

An investigation is reported of the energy partition to the workpiece for grinding of silicon nitride with diamond wheels. The energy input to the workpiece was obtained by measuring the temperature response in the subsurface using a two-color infrared detector and matching the results to analytically computed values. Temperature measurements obtained with a two-color detector should be independent of the emissivity of the workpiece material, which is an important advantage over a single-color detector. Measured temperature responses were in good agreement with analytical predictions for a moving heat source with a triangular distribution at the grinding zone. It was found that about 16 to 24% of the energy is transported as heat to the workpiece for wet grinding and 59% for dry grinding.
Investigating the Relationship between Elementary Teacher Mathematics Anxiety, Mathematics Instructional Practices, and Student Mathematics Achievement

Many elementary teachers have been found to have high levels of Many elementary teachers have been found to have high levels of mathematics anxiety but the impact on student achievement was unknown. Elementary teachers ( N = 692) completed the modified Mathematics Anxiety Rating Scale-Revised (Hopko, 2003) along with a questionnaire probing anxiety about teaching mathematics and current mathematics instructional practices. Student mathematics achievement data were collected for the classrooms taught by the teachers. A positive relationship was found between anxiety about mathematics and anxiety about teaching mathematics. Increased student mathematics achievement was related to lower levels of anxiety about teaching mathematics, but was not related to general anxiety about mathematics. Anxiety about mathematics was positively related to more National Council of Teachers of Mathematics (NCTM) Standards-based instructional practices.
Targeting and Degradation of Viral DNA by the CRISPR-Cas System of Escherichia Coli

Bacteria and archaea maintain a history of viral infections by integrating small fragments of foreign DNA into specialized genomic loci called clustered regularly interspaced short palindromic repeats (CRISPRs). Subsequent infections trigger an adaptive immune response, which relies on both CRISPR RNAs (crRNAs) and CRISPR-associated (Cas) proteins to identify and destroy invading DNA. In E. coli, the crRNA/Cas ribonucleoprotein surveillance complex is referred to as Cascade. Cascade recognizes foreign DNA targets via crRNA-DNA base pairing and subsequently recruits a trans-acting nuclease/helicase, Cas3, for degradation of the targeted DNA. To fully dissect the mechanistic features of target recognition and degradation by Cascade/Cas3, we have used a combination of single molecule and bulk methods. We reveal crucial features in DNA that Cascade senses to locate and recognize complementary target sequences within the larger context of genomic DNA. Further, we uncover the key elements necessary for Cascade-dependent recruitment of Cas3. Finally, by directly visualizing Cas3 as it unwinds and cleaves viral DNA, we characterize the degradation machinery in exceptional detail, providing fundamental insights into the mechanism of CRISPR-based immunity. Importantly, by comparing these results with our recent findings for another CRISPR-Cas system, Cas9 in S. pyogenes, we can begin to understand the evolution of DNA targeting machineries in related RNA-based adaptive immune systems.
Fatigue crack growth and fracture paths in sand cast B319 and A356 aluminum alloys

The effect of heat-treatment on the fatigue crack growth and fracture paths in lost foam sand cast B319 and A356 Al has been examined by in situ testing in a scanning electron microscope. Fatigue crack growth and fracture toughness experiments were performed at ambient temperature on B319 Al in T5, T6, and T7 conditions and on A356 in the T6 condition to characterize the crack path and the interaction of the crack-tip with the microstructure. High-resolution micrographs of the near-tip region were analyzed using a machined-vision-based stereoimaging technique, known as DISMAP, to determine the crack-tip displacement and strain fields. Selected-area energy dispersive spectroscopy was used to identify the particles in the wake of the fatigue cracks, as well as the alloy content of the Al-matrix ahead of the crack-tip. Microhardness tests revealed the presence of hard and soft zones in B319-T6 that the fatigue cracks tended to follow. The fatigue crack growth rate was reduced and the crack path altered when the crack-tip interacted with (1) localized shear bands, (2) interdendritic boundaries, (3) particle/matrix interface, (4) shrinkage pores, and (5) fractured particles. The decrease in the fatigue crack growth rate can be attributed to increasing crack-tip shielding due to crack branching and deflection. The fracture toughness of A356-T6 is higher than the B319 materials because of the absence of shear localization in the matrix.
Sulfone‐Containing polymers as high barrier materials

Three types of sulfone-containing polymers, poly(carbonate-sulfone)s, poly(ester-sulfone)s, and poly(urethane-sulfone)s, were characterized as high barrier materials. They were made by condensing sulfone-containing diol, 1,3-bis(3-hydroxypropylsulfonyl)propane (Diol-333), or 1,4-bis(3-hydroxypropylsulfonyl)butane (Diol-343), with diphenyl carbonate, diphenyl esters, and diisocyanates, respectively. The incorporation of polar sulfone groups into polymer backbones increases the glass transition temperature of polymers in all cases; however, the increment is different with different functional linkages. The increments in polycarbonates and polyesters are higher than that in polyurethanes. This is because the interactions between carbonate or ester groups are much weaker than the interactions between sulfone groups, whereas the hydrogen bonding between urethane groups is comparable with the polar interaction between sulfone groups. The polymers were coated on 50-μm-thick Kapton films by solution casting and their permeabilities toward carbon dioxide were measured at 25°C using the ASTM D1434 volumetric method. The sulfone-containing polymers have carbon dioxide permeability coefficients at least 50 times smaller than the corresponding polymers without sulfone groups. The carbon dioxide barrier properties of sulfone-containing polymers are comparable with ethylene/vinyl alcohol copolymers (EVAL), which are commercial high barrier polymers. An isomer effect on polymer permeability was observed in the aromatic-aliphatic poly(ester-sulfone) series. The permeability coefficients of the aromatic-aliphatic poly(ester-sulfone)s decrease from terephthalate to isophthalate to phthalate, corresponding to the increase of chain flexibility above the Tg. These results support the hypothesis that high chain flexibility in the rubbery state and a glass transition temperature above room temperature are two key factors that promote low permeability. © 1994 John Wiley & Sons, Inc.
Nature's Longing for Beauty: Elegance as an Evolutionary Attractor, with Implications for Human Systems

This article suggests that the tendency of living systems to move toward more practical and more aesthetically fitting states be hypothesized as an evolutionary principle. The viewpoints of scientists and systems thinkers on the place of elegance in nature are considered, along with a discussion of issues related to perception of beauty. Implications for human systems and for meeting the challenges we presently face are considered.
Time-Resolved Studies of Fluorescence Quenching in Supercritical Carbon Dioxide: System Dependence in the Enhancement of Bimolecular Reaction Rates at Near-Critical Densities

The quenching of anthracene, perylene, 9-cyanoanthracene (9CA), and 9,10-diphenylanthracene (DPA) excited singlet states by carbon tetrabromide (CBr4) in supercritical CO2 has been studied systematically by use of the time-resolved fluorescence method. For 9CA−CBr4 and DPA−CBr4, there is enhanced fluorescence quenching at near-critical CO2 densities. On the other hand, the CO2 density dependence of fluorescence quenching in the anthracene−CBr4 and perylene−CBr4 systems follows the prediction of the hydrodynamic Smoluchowski equation for diffusion-controlled reactions. The results show, for the first time, that the enhancement in bimolecular fluorescence quenching reactions due to effects of local quencher concentration augmentation in supercritical CO2 is in fact system dependent.
Metabotropic glutamate receptor 5 regulates excitability and Kv4.2-containing K+ channels primarily in excitatory neurons of the spinal dorsal horn

Metabotropic glutamate (mGlu) receptors play important roles in the modulation of nociception. Previous studies demonstrated that mGlu5 modulates nociceptive plasticity via activation of ERK signaling. We have reported recently that the Kv4.2 K+ channel subunit underlies A-type currents in spinal cord dorsal horn neurons and that this channel is modulated by mGlu5-ERK signaling. In the present study, we tested the hypothesis that modulation of Kv4.2 by mGlu5 occurs in excitatory spinal dorsal horn neurons. With the use of a transgenic mouse strain expressing enhanced green fluorescent protein (GFP) under control of the promoter for the γ-amino butyric acid (GABA)-synthesizing enzyme, glutamic acid decarboxylase 67 (GAD67), we found that these GABAergic neurons express less Kv4.2-mediated A-type current than non-GAD67-GFP neurons. Furthermore, the mGlu1/5 agonist, (R,S)-3,5-dihydroxyphenylglycine, had no modulatory effects on A-type currents or neuronal excitability in this subgroup of GABAergic neurons but robustly modulated A-type currents and neuronal excitability in non-GFP-expressing neurons. Immunofluorescence studies revealed that Kv4.2 was highly colocalized with markers of excitatory neurons, such as vesicular glutamate transporter 1/2, PKCγ, and neurokinin 1, in cultured dorsal horn neurons. These results indicate that mGlu5-Kv4.2 signaling is associated with excitatory dorsal horn neurons and suggest that the pronociceptive effects of mGlu5 activation in the spinal cord likely involve enhanced excitability of excitatory neurons.
Configuration of the high-latitude thermosphere neutral circulation for IMF By negative and positive

Asymmetries in the Northern Hemisphere neutral circulation that are dependent on the sign of the east-west 'B(y)' component of the IMF are presently illustrated by measurements of the neutral wind in the polar F-region which were conducted by the DE-2 spacecraft. The data thus obtained are categorized according to the sign of the hourly averaged IMF B(y) component measured by ISEE-3 for the hour preceding the DE-2 measurements. It is noted that there is (1) an asymmetry in the polar cap neutral flow velocity, with the region of most rapid antisunward flow shifting from the dawn side to the dusk side of the polar cap as B(y) changes from positive to negative; (2) a shift occurs in the magnetic local time of the region of entry of neutral gas into the polar cap, from a location on the dawn side of the moon-midnight meridian for B(y) positive to one more biased, for B(y) negative; and (3) there is an enhancement of velocities associated with the dawn anticlockwise neutral vortex for B(y) negative relative to those observed for B(y) positive.
Standardization of International Marketing Strategy: Some Research Hypotheses:

Two aspects of international marketing strategy standardization are process and program standardization. A framework for determining marketing program standardization is introduced. Factors affecti...
New perspectives in primate cognitive ecology.

The papers in this issue are from a symposium presented at the 71st Annual Meeting of the American Association of Physical Anthropologists held in Buffalo, New York, in April 2002. In the light of recent theoretical and methodological advances and debates in the study of cognition, this symposium addressed questions concerning primate cognitive ecology and decision-making from a variety of perspectives. These include ontogenetic patterns of brain growth and learning, paleoecology and evolution, sensory adaptations, foraging strategies, tool-using behavior, and concepts derived from the study of human cognition, such as schemata, planning, and rehearsal of activities. In this issue, data are presented on New World monkeys, Old World monkeys, apes, and humans. It is argued that the ability to make decisions based on the recognition that tertiary relationships in one context can be used to understand cause-and-effect relationships in an unrelated context may enable nonhuman primates to effectively reduce uncertainty and solve problems in changing social and ecological environments. Am. J. Primatol. 62:133–137, 2004. © 2004 Wiley-Liss, Inc.
Execution of Necrotic-Like Cell Death in Caenorhabditis elegans Requires Cathepsin D Activity.

INTRODUCTION. Inappropriate cell death underlies the pathology of many human and animal diseases. In particular, premature neuronal cell death plays a significant role in several late onset degenerative disorders such as Alzheimer's Disease and Amyotrophic Lateral Sclerosis (1). The mechanisms of execution of pathological or necrotic cell death are not clear, but a detailed molecular model of inherited neurodegenerative conditions, identified in the nematode Caenorhabditis elegans, is emerging and may provide a means of identifying a conserved pathway for pathological cell death in humans (2). Gain-of-function mutations in several, specific, C. elegans ion channel genes encode hyperactive channels that induce necrotic-like death of the neurons that express these channel genes. For example, dominant mutations in the mec-4 gene (mechanosensory; mec-4 allele u231 or d: dominant) induce degeneration of six touch receptor neurons required for the sensation of gentle touch to the body (3,4). We are investigating the requirements for the progression and execution of degenerative cell death inflicted by mec-4(d) and other insults in C. elegans. To highlight the molecular events that transpire during neurodegeneration we have embarked on an effort to define conditions that block or interfere with necrotic-like cell death. We report here that Cathepsin D, which is an aspartyl protease, is required for the execution of necrotic-like cell death in C. elegans.
Nuclear and Coulomb deformation parameters of 142Nd

Abstract Nuclear and Coulomb deformation parameters have been deduced from DWBA analyses of angular distributions of 67.5 MeV 13C ions inelastically scattered from 142Nd. Optical model parameters from fits of measured elastic scattering data were used with previously measured B(EL) values to determine initial deformation parameters. Comparison With the experimental data indicates that DWBA calculations can be used to understand the inelastic scattering from the nearly spherical nucleus 142Nd.
The distribution of rapidly hybridizing RNA sequences in heterogeneous nuclear RNA and mRNA from HeLa cells.

Both HnRNA and mRNA contain sequences derived from DNA which is reiterated many times in the cell genome. The degree of reiteration for sites binding HnRNA appears to be greater than for those DNA sites which bind mRNA.
THE PREVENTION OF ANEMIA IN HYPOPHYSECTOMIZED ADULT FEMALE RATS WITH COMBINED THYROXINE AND CORTISONE THERAPY1

ALTHOUGH it has been well established that hypophysectomy induces i i an anemia (see reviews by Gordon and Charipper, 1947, and Daughaday, Williams and Daland, 1948), the mechanism by which removal of the hypophysis causes this anemia is still a problem. Many different means of therapy have been utilized in an attempt to prevent anemia in hypophysectomized rats, but the only ones that proved to be completely effective have been pituitary extracts (Flaks, Ilimmel, and Zoltnik, 1938; Contopoulos, Van Dyke, Simpson, Garcia, Huff, Williams and Evans, 1953), a combination of thyroxine and androgen (Crafts, unpublished data), a combination of thyroxine, androgen, and high protein diet (Crafts, 1949), cobalt nitrate (Crafts, 1952; Garcia, Van Dyke, and Berlin, 1952), and adrenocorticotrophic hormone (Garcia, Van Dyke, Huff, Elmlinger and Oda, 1951). Thyroidectomy in rats has been shown to induce a moderate anemia but the anemia was not as severe as has been found after hypophysectomy (Crafts, 1941; Wilson, 1944;...
Adaptive clustering neural net for piecewise nonlinear discriminant surfaces

A three-layer adaptive clustering neural net is described for distortion-invariant multiclass object recognition in difficult problems requiring piecewise nonlinear discriminant surfaces. The number of hidden-layer neurons is determined by an organized procedure (several neurons are used per class as prototypes of each class). These are chosen by clustering techniques. The vector description of each prototype in the multidimensional input feature space specifies a set of linear discriminant functions that are the initial input to the hidden-layer weights used. These weights are then refined by a neural net algorithm using conjugate gradient techniques to produce the final weights. A neural net (NN) that marries pattern-recognition and NN techniques is thus obtained. Various multiclass distortion-invariant classification results are presented
Software-Based Algorithm for Modeling and Correction of Gradient Nonlinearity Distortions in Magnetic Resonance Imaging

Functional radiosurgery is a noninvasive stereotactic technique that requires magnetic resonance image (MRI) sets with high spatial resolution. Gradient nonlinearities introduce geometric distortions that compromise the accuracy of MRI-based stereotactic localization. We present a gradient nonlinearity correction method based on a cubic phantom MRI data set. The approach utilizes a sum of spherical harmonics to model the geometrically warped planes of the cube and applies the model to correct arbitrary image sets acquired with the same scanner. In this paper, we give a detailed description of the Matlab distortion correction program, report on its performance in stereotactic localization of phantom markers, and discuss the possibility to accelerate the code using general-purpose computing on graphics processing units (GPGPU) techniques.
Sls1p is a membrane-bound regulator of transcription-coupled processes involved in Saccharomyces cerevisiae mitochondrial gene expression

Mitochondrial translation is largely membrane-associated in S. cerevisiae. Recently, we discovered that the matrix protein Nam1p binds the amino-terminal domain of yeast mtRNA polymerase to couple translation and/or RNA-processing events to transcription. To gain additional insight into these transcription-coupled processes, we performed a genetic screen for genes that suppress the petite phenotype of a point mutation in mtRNA polymerase (rpo41-R129D) when overexpressed. One suppressor identified in this screen was SLS1, which encodes a mitochondrial membrane protein required for assembly of respiratory-chain enzyme complexes III and IV. The mtRNA-processing defects associated with the rpo41-R129D mutation were corrected in the suppressed strain, linking Sls1p to a pathway that includes mtRNA polymerase and Nam1p. This was supported by the observation that SLS1 overexpression rescued the petite phenotype of a NAM1 null mutation. In contrast, overexpression of Nam1p did not rescue the petite phenotype of a SLS1 null mutation, indicating that Nam1p and Sls1p are not functionally redundant but rather exist in an ordered pathway. On the basis of these data, a model in which Nam1p coordinates the delivery of newly synthesized transcripts to the membrane, where Sls1p directs or regulates their subsequent handling by membrane-bound factors involved in translation, is proposed.
Axonal bifurcation in the dorsal root ganglion of the cat: A light and electron microscopic study

Bifurcation of the axon of unipolar neurons in the dorsal root ganglion of the cat has been studied by light and electron microscopy. Osmic acid, Golgi and silver preparations have revealed two types of bifurcation: (1) of myelinated fibers characterized by constriction at the nodal region with peripheral and central branches of equal diameter; (2) of small fibers characterized by a broad triangular expansion at the junctional region with a much thicker peripheral as compared to the central branch. These differences in bifurcation of unmyelinated and myelinated axons can be related to the velocity of conduction in the peripheral nerve and dorsal roots. The ultrastructure of the nodal region at the bifurcation resembles the node of Ranvier of a peripheral nerve fiber. The node of Ranvier at the bifurcation consists of three cells of Schwann and adjacent cells are closely apposed and interdigitated. Neurofilaments and microtubules are prominent structures within the axoplasm at the nodal regions. They group into two streams as the unipolar process bifurcates, entering the peripheral and central branch respectively. At the junctional region within the axoplasm, numerous mitochondria and scattered multivesicular bodies are always observed.
Portal Vein Stenosis: A Rare Yet Clinically Important Cause of Delayed-onset Ascites after Adult Deceased Donor Liver Transplantation: Two Case Reports

Vascular complications following liver transplantation are well documented. While complications involving the portal vein are less common than the hepatic artery, portal vein complications can lead to potentially life-threatening sequelae including graft loss. Portal vein stenosis is an infrequent complication following liver transplant. The majority of these complications are seen in living donor liver transplants and pediatric liver transplants. We present 2 cases of delayed onset portal vein stenosis in adult deceased donor liver transplantation (ADDLT). The first patient presented with refractory ascites twelve months after ADDLT. He was diagnosed and successfully treated with percutaneous transhepatic portovenography and venoplasty. The second patient had a history of irradiation to his portal bed in the setting of cholangiocarcinoma. He developed refractory ascites and esophageal variceal bleeding>2 years after ADDLT. He underwent percutaneous transhepatic portovenoplasty, but eventually required placement of a portal stent due to continued problems with recurrent ascites. These 2 cases highlight the importance of considering portal vein stenosis in the differential diagnosis of late-onset ascites following liver transplantation, especially if there have been any predisposing risk factors such as portal bed irradiation or prior splenectomy.
Economic development, demographics, and renewable resources: a dynamical systems approach

Many developing economies are faced with growing populations and deteriorating natural resources. It is often argued that economic growth will arrest these trends via cleaner technology and social change accompanied by reduced birth rates. Two questions arise: (1) What general economic, demographic, and ecological conditions favor this scenario? and (2) What adjustments, technological, demographic, or ecological, are more important in realizing this scenario? I address these questions using a two-sector growth model which includes human demographics and a renewable resource base. Using powerful numerical bifurcation techniques and rescaling arguments, I obtain the following general results. If the regeneration rate of the renewable resource base is slow relative to the rate of economic growth, population overshoot and resource collapse is more likely. Demographic adjustments are more important than technological adjustments in avoiding renewable resource degradation. Several related results are presented that support these general findings.
Absolute spectral responsivity measurements of solar cells by a hybrid optical technique.

An irradiance mode, absolute differential spectral response measurement system for solar cells is presented. The system is based on combining the monochromator-based approach of determining the power mode spectral responsivity of cells with an LED-based measurement to construct a curve representing the light-overfilled absolute spectral response of the entire cell. This curve can be used to predict the short-circuit current (Isc) of the cell under the AM 1.5 standard reference spectrum. The measurement system is SI-traceable via detectors with primary calibrations linked to the NIST absolute cryogenic radiometer. An uncertainty analysis of the methodology places the relative uncertainty of the calculated Isc at better than ±0.8%.
Optimally stable parallel predictors for Adams—Moulton correctors

Abstract The stability properties of a class of predictor—corrector algorithms which are designed for parallel computation in the numerical solution of systems of ordinary differential equations are studied. It is shown that if the corrector is fixed to be an Adams—Moulton Corrector, then the optimally stable parallel predictor (in the sense that the parallel scheme has a maximum stability interval on the negative real axis) is the Adams—Bashforth predictor shifted to the right by one integration step. The size of the stability intervals on the negative real axis in optimally stable algorithms of various orders are compared with those of the standard serial Runge—Kutta and serial predictor—corrector methods. Corresponding stability regions in the complex plane are presented for fourth order algorithms and the results are illustrated by sample problems.
Evaluating particle scattering effects by using turbulence scattering theories

The possibility of an alternative approach for particle scattering is presented. In this approach, a correlation function is derived that describes the permittivity fluctuations due to sharp gradients at the boundary of a particle and the particle distributions to the level of pair correlation. Once such a correlation function is available, some conceptions of turbulence scattering become eligible for application. Analytic results in the cases when the permittivity contrast is weak or the particle size is small are shown to be in good agreement with the corresponding ones that are obtained by using the conventional approach. This new approach is expected to be useful in solving some difficult problems in particle scattering systems such as computing the higher moments and temporal behavior, at least in the extreme cases mentioned above.
Renters' Illusion or Savvy?

A frequent finding in the local public finance literature is that renters are more likely to support expansions in the local budget than are homeowners. The renters' illusion hypothesis (renters are less aware of tax increases than are homeowners) has been commonly used to explain this behavior This article examines the alternative hypothesis of renters' rationality. It is argued that renters' behavior is a rational and selfish response to a fiscal environment that provides them, as a group, with larger net benefits than it doesfor homeowners. I use bond referendum data to show that, even when renters and homeowners of the same income level are assumed to receive the same net benefits, it is erroneous to interpret the stronger support by renters of the proposals, as previous literature has, as a manifestation of fiscal illusion. The article also makes an attempt to estimate different net benefits from the referendum for renters and homeowners of different income levels.
Internal anatomy of individual tomato seeds: relationship to abscisic acid and germination physiology

Tomato seeds that have been dried, imbibed and redried (primed) develop internal free space between the embryo and endosperm. Seeds of the ABA-deficient sitiens(sitw) tomato mutant can exhibit internal free space at the completion of seed development even without priming. Both primed and sitwseeds germinate more rapidly than untreated wild-type seeds. To determine whether internal anatomy predicts germination physiology, individual sitwand primed wild-type seeds were sorted into three categories based upon the extent of internal free space observed non-destructively using X-radiography. Category 3 (C3, extensive free space present) sitw seeds completed germination more rapidly than all other seed categories and genotypes in water, in abscisic acid (ABA) or under far-red illumination. The force necessary to puncture the endosperm caps (and testa) of C3 sitw seeds was less, and the percentage of nuclei in C3 sitw radicle tips in the G2 stage of the cell cycle was greater than for all other seed categories. Wild-type seeds exhibited free space following long-term priming, but germination was still prevented by far-red light and ABA, and endosperm cap strength and nuclear DNA contents were not altered. Endo-β-mannanase activity of individual endosperm caps was not consistently related to their resistance to puncture. While internal free space is diagnostic for primed tomato seeds and occurs in a fraction of sitw seeds, it is not predictive of many aspects of germination physiology.
Imaging local electric fields produced upon synchrotron X-ray exposure

Electron–hole separation following hard X-ray absorption during diffraction analysis of soft materials under cryogenic conditions produces substantial local electric fields visualizable by second harmonic generation (SHG) microscopy. Monte Carlo simulations of X-ray photoelectron trajectories suggest the formation of substantial local electric fields in the regions adjacent to those exposed to X-rays, indicating a possible electric-field–induced SHG (EFISH) mechanism for generating the observed signal. In studies of amorphous vitreous solvents, analysis of the SHG spatial profiles following X-ray microbeam exposure was consistent with an EFISH mechanism. Within protein crystals, exposure to 12-keV (1.033-A) X-rays resulted in increased SHG in the region extending ∼3 μm beyond the borders of the X-ray beam. Moderate X-ray exposures typical of those used for crystal centering by raster scanning through an X-ray beam were sufficient to produce static electric fields easily detectable by SHG. The X-ray–induced SHG activity was observed with no measurable loss for longer than 2 wk while maintained under cryogenic conditions, but disappeared if annealed to room temperature for a few seconds. These results provide direct experimental observables capable of validating simulations of X-ray–induced damage within soft materials. In addition, X-ray–induced local fields may potentially impact diffraction resolution through localized piezoelectric distortions of the lattice.
On the Powerful Use of Simulations in the Quake-Catcher Network to Efficiently Position Low-cost Earthquake Sensors

The Quake-Catcher Network (QCN) uses low-cost sensors connected to volunteer computers across the world to monitor seismic events. The location and density of these sensors' placement can impact the accuracy of the event detection. Because testing different special arrangements of new sensors could disrupt the currently active project, this would best be accomplished in a simulated environment. This paper presents an accurate and efficient framework for simulating the low cost QCN sensors and identifying their most effective locations and densities. Results presented show how our simulations are reliable tools to study diverse scenarios under different geographical and infrastructural constraints.
Long-distance Commuting by Brown-headed Cowbirds in New Mexico

The Brown-headed Cowbird (Molothrus ater) is a widespread brood parasite that has attracted considerable recent attention as a possible threat to forestdwelling songbirds (e.g. Finch 1991, Robinson et al. 1995). Cowbirds are unusual among passerines in that their parasitic nature allows some populations to have spatially and temporally separate breeding and feeding activities (Rothstein et al. 1984). Cowbirds are ground foragers that feed in open habitats such as grazed grasslands, agricultural fields, livestock corrals, and mowed lawns (Friedmann 1929, Mayfield 1965, Ortega 1998). For breeding, however, cowbirds occupy a wider variety of habitats where their passerine hosts occur in higher densities (Robinson et al. 1995). This reliance on distinct habitat types for essential activities gives rise to daily commuting patterns in landscapes where breeding and feeding habitats are spatially separated (Rothstein et al. 1984, Thompson 1994, Gates and Evans 1998). Cowbirds are restricted to parasitizing nests that are within commuting distances of their feeding habitats. In recent years, recognition of the relationship between feeding and breeding habitats of cowbirds has led to management strategies involving the manipulation of feeding habitats to alter cowbird breeding distributions for the benefit of potential hosts. For example, in the Coconino National Forest, Arizona, managers rotate livestock (which enhance feeding opportunities for cowbirds) away from nesting sites of endangered Southwestern Willow Flycatchers (Empidonax traillii extimus; Goguen and Mathews 1999). For such strategies to effectively protect hosts, the scale at which they are implemented must be sufficient to discourage cowbirds from commuting. The maximum commuting distance between breeding and feeding sites of cowbirds is one of several factors needed to determine the correct scale of management efforts for cowbirds. In previous radio-telemetry studies, the longest observed commute between breeding and feeding areas of female cowbirds has been around 7 km (Rothstein et al. 1984, Thompson 1994, Gates and Evans 1998). This distance has been used as an estimate of the maximum commuting distance for female cowbirds (e.g. Gustafson and Crow 1994, Coker and Capen 1995) and is the distance used for livestock removal in some cowbird management efforts (e.g. Goguen and Mathews 1999). Given the conservation implications, it is necessary to
Novel dual PPARα/γ ligands, TZD18 and compound 48, as growth inhibitors of CML cell lines

AACR Annual Meeting-- Apr 14-18, 2007; Los Angeles, CA 5612 Despite of progress in therapy of CML with imatinib, resistances during treatment frequently occur and remain a therapeutic challenge. In this study, we investigated the activity of two novel dual ligands specific for peroxisome proliferator-activated receptor α and γ (PPARα/γ), TZD18 and compound 48 (C48), against CML cell lines. Culture of CML cell lines, both imatinib-sensitive (K562, KU812 and KCL22) and -resistant (K562sr, KU812sr and KCL22sr), with TZD18 or C48 resulted in growth inhibition in a dose- and time-dependent manner without obvious toxicities on normal CD34 positive hematopoietic stem cells as assessed by clonogenic assay. The observed inhibition was much stronger than that either of conventional PPARγ ligand, pioglitazone (PGZ) or PPARα ligand, WY14,643. However, these effects seemed not to be mediated by activation of either PPARα or γ receptors, since antagonists for PPARγ and/or PPARα could not reverse these inhibitions. G0/G1 cell cycle arrests have been observed after exposure to TZD18 or C48 indicating that inhibition of cell cycle progression may account for the observed growth inhibition. Western blot analysis of cell cycle regulators confirmed these results, namely, expression of cyclin dependent kinase (CDK) inhibitor p27kip1 was enhanced, whereas levels of cyclin E, cyclin D2 and CDK 2 were decreased when these cells were treated with either TZD18 or C48. Recent published data indicates that autocrine secretion of GM-CSF is crucial for growth and imatinib resistance of CML cells. We found now, for the first time, that both TZD18 and C48 reduced the secretion of GM-CSF significantly in both imatinib-sensitive and -resistant CML cells suggesting that interference of autocrine growth regulation by GM-CSF may be one of the mechanisms responsible for PPARα/γ ligands induced growth inhibition in CML cells. Finally, of more clinical importance, these ligands enhanced either additively or synergistically the anticancer-effects of imatinib in both imatinib-sensitive and -resistant cells. Overall, our findings clearly suggest that these PPARα/γ ligands, alone or in combination with imatinib, may have potential clinical application in treatment of CML in an adjuvant setting either before or after development of imatinib resistance.
Modeling coupled convection and carbon dioxide injection for improved heat harvesting in geopressured geothermal reservoirs

Geopressured geothermal saline aquifers are an abundant low-enthalpy geothermal energy resource available in many coastal regions including the US Gulf of Mexico. In such geographic areas thick geopressured sandstones (up to several hundred meters thick) hold tremendous geothermal heat with conservative estimates of gross extractable energy approximately 0.2 EJ per cubic kilometer of the formation. Additionally, widespread geopressure in sedimentary deposits of the Gulf region preserves favorable petrophysical properties of unconsolidated sandstones such as high porosity and permeability, thus, enhancing productivity and economics of potential heat harvesting projects. In this study we investigate the potential of a typical geopressured reservoir in the US Gulf coast to deliver commercial quantities of geothermal heat with the possibility of simultaneous supercritical CO2 sequestration into the same formation. Specifically, we focus on numerical simulation study of heat extraction from a model based on the Camerina A sand of South Louisiana. In our numerical experiments, we consider both theoretical and practical implications of combining a traditional heat harvesting method with supercritical CO2 injection. Moreover, this study pays specific attention to the effect of natural convection due to the formation’s tilt and uneven heating at the reservoir boundaries and its impact on the forced convection due to geofluid withdrawal. The numerical simulation results suggest that introduction of supercritical CO2 might have an observable positive effect on the ultimate heat recovery and that a strategic injection/production well placement might further enhance density-driven flows inside the geothermal formation.
Selecting uveal melanoma for PRAME‐TCR T cell immunotherapy

Purpose To determine which uveal melanoma may be candidates for PRAME-directed immunotherapy using TCR-modified autologous T cells. Methods Expression of PRAME was determined in uveal melanoma by an Illumina array. HLA polymorphisms were determined on peripheral blood leukocytes. Clinical and histological characteristics of UM were derived from clinical charts and pathology reports. Results PRAME expression was highly variable; tumor size, thickness, and the presence of an inflammatory phenotype were associated with PRAME expression. 20/37 monosomy 3 cases expressed PRAME, and 8/20 disomy 3 tumors. 10-year survival data on 60 UM showed worse survival of UM with high PRAME compared to those with a low PRAME. However, six of the eight PRAME-positive disomy 3 cases died from metastases. With this information, all cases with PRAME-positive primary tumors who carry the HLA-A2 antigen should be followed closely for the development of metastases, as they can be candidates for PRAME-TCR autologous T cell therapy. Conclusions Uveal melanoma may be good candidates for treatment with autologous T cells that have been modified so that they carry PRAME-specific T cell receptors. Large uveal melanoma with a high PRAME expression (independent of chromosome 3 status) in HLA-A2 positive patients are potential candidates for PRAME-TCR autologous T cell therapy. A high PRAME expression, also in disomy 3 tumors, was associated with an inflammatory phenotype and with death due to metastases.
Role of the Collecting Duct Renin Angiotensin System in Regulation of Blood Pressure and Renal Function

Recent evidence suggests that the renal tubular renin angiotensin system regulates urinary Na(+) and water excretion and blood pressure. Three key components of the tubular renin angiotensin system, namely renin, prorenin receptor, and angiotensin-II type 1 receptor, are localized to the collecting duct. This system may modulate collecting duct Na(+) and water reabsorption via angiotensin-II-dependent and angiotensin-II-independent pathways. Further, the system may be of greatest relevance in hypertensive states and particularly those characterized by high circulating angiotensin-II. In this review, we summarize the current knowledge on the synthesis, regulation, and function of collecting duct-derived renin angiotensin system components and examine recent developments with regard to regulation of blood pressure and renal fluid and Na(+) excretion.