cssi/SciSciGPT-SciSciNet huggingface dataset:
HIV infection in the elderly

The prevalence of HIV in patients over the age of 50 years is increasing. Although older patients may achieve equal or better virologic suppression at equal rates compared with younger patients, the immunologic benefit of highly active antiretroviral therapy (HAART) in older patients may be reduced compared with younger patients. Comorbidities are more common in older patients than younger patients and can impact management of HIV in these patients. Providers must be cognizant of drug-drug interactions and side effects of HAART regimens when selecting an antiretroviral regimen in older HIV patients. As the HIV-infected population ages, there is a growing need to better determine the ideal HAART regimen and timing of HAART initiation in older patients.
It's about time: Forecasting the 2008 presidential election with the time-for-change model

Abstract The popular vote for president can be predicted accurately before the national nominating conventions based on three factors: the incumbent president's approval rating at mid-year, the growth rate of the economy during the first half of the election year, and the length of time that the president's party has controlled the White House. Regardless of who wins the Democratic and Republican nominations, 2008 will be a time-for-change presidential election. Based on President Bush's approval rating in June of 2007, the recent growth rate of the economy, and the fact that the Republican Party will have controlled the White House for eight years, the Democratic nominee would be predicted to win the national popular vote by a comfortable margin. For the Republican nominee to have a reasonable chance of winning the 2008 presidential election, there would have to be a dramatic improvement in President Bush's approval rating during the next 12 months.
Fused Silica for 157 nm Transmittance

The use of silica glass for the photomask material in 157-nm lithography tools is proposed. While fused silica enjoys widespread application for 248 and 193-nm optics, its use for 157-nm applications has been largely discounted, in part because of low transmittance at this wavelength. It is demonstrated here that silica glass can be made to have high transmittance at 157-nm. This is accomplished by minimizing the OH content of the glass. It is also noted that the thermal and mechanical properties of so-called dry silica are very close to higher OH silicas that are commonly used for lithography applications.
Retinal pathway origins of the pattern ERG of the mouse

This study investigated contributions from the retinal On and Off pathways, and the spiking and nonspiking activity of neurons in those pathways to the pattern ERG of the mouse. Light-adapted pattern and ganzfeld ERGs were recorded from anesthetized C57BL/6 mice 3-4 months of age. Recordings were made before and after intravitreal injections of PDA (cis-2,3-piperidine-dicarboxylic acid) to block transmission to hyperpolarizing 2nd order and all 3rd order neurons, TTX (tetrodotoxin) to block Na(+)-dependent spiking, APB (2-amino-4-phosphonobutyric acid) to block synapses between photoreceptors and ON-bipolar cells, and APB + TTX and PDA + TTX cocktails. The pattern stimuli consisted of 0.05 cy/deg gratings reversing in contrast at 1 Hz, presented at various contrasts (50-90%) and a rod saturating mean luminance. For flash ERGs, brief green ganzfeld flashes were presented on a rod-suppressing green background. Recordings were made 39-42 days after unilateral optic nerve crush (ONC) in a subset of animals in which ganglion cell degeneration was subsequently confirmed in retinal sections. Pattern ERGs were similar in waveform for all contrasts, with a positive wave (P1) peak for 90% contrast around 60 ms on average and maximum trough for a negative wave (N2) around 132 ms after each contrast reversal; amplitudes were greatest for 90% contrast which became the standard stimulus. ONC eliminated or nearly eliminated the pattern ERG but did not affect the major waves of the flash ERG. PDA and TTX both delayed P1 and N2 waves of the pattern ERG, and reduced their amplitudes, with effects of PDA on N2 greater than those of TTX. In the flash ERG, PDA reduced a-wave amplitudes, removed OPs but hardly affected b-wave amplitudes. In contrast, TTX reduced b-wave amplitudes substantially, as previously observed in rat. APB removed P1 of the pattern ERG, but left a negative wave of similar timing and amplitude to N2. In the flash ERG, APB removed the b-wave, producing a negative ERG. Addition of TTX to the APB injection removed most of N2 of the pattern ERG, while other waves of the pattern and flash ERG resembled those after APB alone. Addition of TTX to the PDA injection had little effect on the pattern ERG beyond that of PDA alone, but it prolonged the b-wave of the flash ERG. In conclusion, this study confirmed that a selective lesion of ganglion cells will practically eliminate the pattern ERG. The study also showed that P1 of the mouse pattern ERG is dominated by contributions, mainly spiking, from ON pathway neurons, whereas N2 reflects substantial spiking activity from the OFF pathway as well as nonspiking contributions from both pathways.
Methylation alterations of WT1 and homeobox genes in inflamed muscle biopsy samples from patients with untreated juvenile dermatomyositis suggest self-renewal capacity.

Objective To determine the effect of methylation alteration in inflamed muscles from children with juvenile dermatomyositis (DM) and other idiopathic inflammatory myopathies (IIMs). Methods Magnetic resonance imaging–directed diagnostic muscle biopsies yielded samples from 20 children with juvenile DM, which were used for genome-wide DNA methylation profiling, as were muscle biopsy samples from 4 healthy controls. Bisulfite treatment followed by pyrosequencing confirmed methylation status in juvenile DM and other IIMs. Immunohistochemistry defined localization and expression levels of WT1. Results Comparison of genome-wide DNA methylation profiling between juvenile DM muscle and normal control muscle revealed 27 genes with a significant methylation difference between the groups. These genes were enriched with transcription factors and/or cell cycle regulators and were unrelated to duration of untreated disease. Six homeobox genes were among them; ALX4, HOXC11, HOXD3, and HOXD4 were hypomethylated, while EMX2 and HOXB1 were hypermethylated. WT1 was significantly hypomethylated in juvenile DM (Δβ = –0.41, P < 0.001). Bisulfite pyrosequencing verification in samples from 56 patients with juvenile DM confirmed the methylation alterations of these genes. Similar methylation alterations were observed in juvenile polymyositis (n = 5) and other IIMs (n = 9). Concordant with the other findings, WT1 protein was increased in juvenile DM muscle, with average positive staining of 11.6%, but was undetectable in normal muscle (P < 0.001). Conclusion These results suggest that affected muscles of children with juvenile DM and IIMs have the capacity to be repaired, and that homeobox and WT1 genes are epigenetically marked to facilitate this repair process, potentially suggesting new avenues of therapeutic intervention.
Local Uniform Mesh Refinement with Moving Grids

Local Uniform Mesh Refinement (LUMR) is a powerful technique for solving hyperbolic partial differential equations. However, many problems contain regions where numerical dispersion is very large, such as steep fronts. In these regions, mesh refinement is not very efficient. A better approach in these regions is to locally transform the coordinate system to move with the front. We show how to combine these two approaches in a way that maintains the advantages of LUMR and the effectiveness of moving grids. Experiments with 2-D scalar problems are presented.
Advances in the treatment of rheumatic interstitial lung disease.

Purpose of reviewInterstitial lung disease frequently complicates the rheumatic diseases. The purpose of this review is to outline recent advances and current concepts regarding the management of these interstitial lung diseases.Recent findingsSeveral histologic lesions cause interstitial lung disea
Infrared observations of the X-ray quasars 0241+622 and MR2251-178

Two new quasars have recently been found through X-ray observations (the only other one being 3C273, see refs 1, 2). Ricker et al. have reported observations confirming the identification of the X-ray source 2251–178 with a quasar of visual magnitude 14.1. Canizares, McClintock, and Ricker have reported visual spectrophotometric observations of this quasar, and find its visual spectrum is much like other low redshift quasars. Apparao et al. have reported the discovery of a low redshift quasar identified with the X-ray source 4U0241 + 61. Margon and Kwitter have reported detailed visual spectrophotometry of this quasar, 0241 + 622, and likewise find that its spectrum is typical of low redshift quasars. Because of the importance of establishing any morphologically unique characteristics of X-ray quasars, these quasars should be observed at all possible wavelengths. We report here IR observations of the two newly discovered X-ray quasars. These observations indicate that the X-ray quasars have IR properties typical of low redshift quasars, and, along with 3C273, are among the brightest known quasars at IR wavelengths.
Excision and transposition of two Ds transposons from the bronze mutable 4 Derivative 6856 allele of Zea mays L.

The regulatory mutation bronze mutable 4 Derivative 6856 (bz-m4 D6856) contains a complex 6.7 kb Dissociation (Ds) element tagged with a duplication of low copy bz 3′ flanking sequences (Klein et al. 1988). This creates a unique opportunity to study the transposition of a single member of the repetitive family of Ds elements. Eighteen full purple revertants (Bz′ alleles) of bz-m4 were characterized enzymatically and by genomic mapping. For 17 of the Bz′ alleles, reversion to a wild-type phenotype was caused by excision of the 6.7 kb Ds transposon. Nine of these Bz′ alleles retained the transposon somewhere in their genome. In this study we show that like Ac (Schwartz 1989; Dooner and Belachew 1989), the 6.7 kb Ds element can transpose within a short physical distance, both proximal and distal to its original position. Additional bz sequences have been mapped immediately distal to the mutant locus in bz-m4 D6856; genetic evidence suggests these are flanked by two additional Ds elements. The remaining Bz′ revertant, Bz′ :107, arose from excision of a more complex 13 kb Ds element.
A novel isoform of Cbl-associated protein that binds protein kinase A

A novel isoform of Cbl-associated protein (CAP) was identified in a yeast two-hybrid screen for A-kinase anchoring proteins expressed in the heart. CAP is a scaffold protein implicated in insulin signaling and cytoskeleton regulation. The protein kinase A binding site is encoded by a previously unidentified, alternatively spliced exon.
Synthesis, Characterization, and Diastereoselectivity of Chloride Substitution Reactions of Cycloruthenated (R)C-(+)-N,N-Dimethyl-α-(2-naphthyl) Ethylamine

The transmetalation reaction of enantiomerically pure 1, with [(η6-C6H6)RuCl2]2 in CH3CN at ambient temperature forms a mixture of two diastereomeric ruthenacycles (SRu, RC), 2a, (96%) and (RRu, RC), 2a‘, (4%) of the type in good chemical and optical yields. The diastereoselectivity of chloride substitution in 2a,a‘ by bromide, iodide, azide, cyanate, thiocyanate, nitrite, allylisonitrile, and selected nitrogen and phosphorus donor ligands has been determined by an appropriate combination of 1H, 13C{1H}, and 31P{1H} NMR spectroscopy, UV−visible spectroscopy, circular dichroism, and single-crystal X-ray crystallography. The diastereoselectivity generally increases with increasing steric bulk of the incoming ligand and proceeds with predominant retention of configuration at ruthenium. The ambidentate ligands, cyanate, thiocyanate, and nitrite all bond to ruthenium exclusively through their nitrogen donor atoms.
vConductor: An enabler for achieving virtual network integration as a service

Network function virtualization is regarded as a promising candidate for future networks. Although many advantages are expected, there is still a lack of services that directly link to increased revenue for telecom operators. Therefore, we propose a new NFV-based service, virtual network integration as a service (VNIaaS). The service allows enterprise network administrators to construct and monitor virtual enterprise networks as necessary. As a key enabler, we further propose vConductor, an innovative technology due to its automatic network provisioning, multi-objective resource scheduling, and NFV-oriented inventory management characteristics. Finally, we show the feasibility through implementation of a prototype system. We believe that this contribution will be a catalyst to accelerate the industrialization of NFV.
TOLERANT ETHANOL ESTIMATION IN FLEX-FUEL VEHICLES DURING MAF SENSOR DRIFTS

Flexible fuel vehicles (FFVs) can operate on a blend of ethanol and gasoline in any volumetric concentration of up to 85% ethanol (93% in Brazil). Existing FFVs rely on ethanol sensor installed in the vehicle fueling system, or on the ethanol-dependent air-to-fuel ratio (AFR) estimated via an exhaust gas oxygen (EGO) or λ sensor. The EGO-based ethanol detection is desirable from cost and maintenance perspectives but has been shown to be prone to large errors during mass air flow sensor drifts [1, 2]. Ethanol content estimation can be realized by a feedback-based fuel correction of the feedforward-based fuel calculation using an exhaust gas oxygen sensor. When the fuel correction is attributed to the difference in stoichiometric air-to-fuel ratio (AFR) between ethanol and gasoline, it can be used for ethanol estimation. When the fuel correction is attributed to a mass air flow (MAF) sensor error, it can be used for sensor drift estimation and correction. Deciding under which condition to blame (and detect) ethanol and when to switch to sensor correction burdens the calibration of FFV engine controllers. Moreover, erroneous decisions can lead to error accumulation in ethanol estimation and in MAF sensor correction. In this paper, we present a cylinder air flow estimation scheme that accounts for MAF sensor drift or bias using an intake manifold absolute pressure (MAP) sensor. The proposed fusion of the MAF, MAP and λ sensor measurements prevents severe mis-estimation of ethanol content in flex fuel vehicles.© 2009 ASME
Ultraviolet photon induced secondary electron emission from TiO2: Theory and experiment

Abstract A theory of ultraviolet photon induced secondary electron emission has been developed which takes into account both the space and energy dependence of electron sources as well as multiple scattering. Ultraviolet photoemission experiments on single crystal surfaces of TiO 2 show that the secondary electron distribution is quite sensitive to the work function of the surface and has distinctive structure. The theory reproduces these features in terms of properties of the empty conduction band states.
A one-residue switch reverses the orientation of a heme b cofactor. Investigations of the ferriheme NO transporters nitrophorin 2 and 7 from the blood-feeding insect Rhodnius prolixus.

This study represents the identification of a single amino acid residue that has the major responsibility for the isomeric orientation of a heme b cofactor in a ferriheme protein. The insertion of hemin b into the asymmetric environment of a protein pocket facilitates two cofactor orientations, A and B, which is often called "heme rotational disorder". The proteins studied herein are nitrophorins, a class of ferriheme proteins found in the saliva of the blood-sucking insect Rhodnius prolixus, in this case NP2 and NP7. NMR spectroscopy (pH* 5.5) of the imidazole complex of NP7 revealed solely the A orientation, whereas NP2 shows primarily the B orientation ( approximately 1:5 A:B). The glutamate 27 residue in NP7 is an obvious difference in the heme pocket compared to those of NP1-4, all of which present a valine residue [valine 24 (NP2 and NP3) or valine 25 (NP1 and NP4)] at the same position. Consequently, the mutant NP2(V24E) was prepared and shown to reverse the heme orientation to exclusively A, whereas NP7(E27V) revealed an approximately 1:3 A:B ratio. The reversal A B following the change glutamine valine was further indicated in circular dichroism (CD) spectroscopy with a positive (A) or negative (B) Deltaepsilon of the heme Soret band. Moreover, CD spectroscopy was applied to the mutant NP7(E27Q) and indicated mainly the A orientation, which allows us to conclude that the steric hindrance provided by the glutamate residue is responsible for the heme orientation rather then the carboxylate charge.
Chromosomal instability is correlated with telomere erosion and inactivation of G2 checkpoint function in human fibroblasts expressing human papillomavirus type 16 E6 oncoprotein

Chromosomal instability is correlated with telomere erosion and inactivation of G2 checkpoint function in human fibroblasts expressing human papillomavirus type 16 E6 oncoprotein
A Protein-tyrosine Kinase-regulated, pH-dependent, Carrier-mediated Uptake System for Folate in Human Normal Colonic Epithelial Cell Line NCM460

Abstract A significant proportion of the bacterially synthesized folate in the large intestine exists in the form of folate monoglutamate. Recent studies in our laboratory using human colonic apical membrane vesicles have shown the existence of an efficient carrier-mediated system for folate uptake. Nothing, however, is known about the cellular regulation of the colonic uptake process. In this study, we used a recently established human normal colonic epithelial cell line NCM460 to address this issue. Uptake of folic acid by NCM460 cells was: 1) linear with time for 4 min of incubation and occurred with minimal metabolic alterations, 2) temperature- and pH- (but not Na+) dependent, 3) saturable as a function of concentration (apparent Km of 1.4 μM), 4) inhibited by structural analogs and anion transport inhibitors, and 5) energy-dependent. These characteristics of folic acid uptake by NCM460 cells are similar to those seen with apical membrane vesicles derived from human native colonic tissue. Using these cells, we found that protein kinase C- and Ca2+/calmodulin-mediated pathways have no role in regulating folic acid uptake. On the other hand, cAMP (through a mechanism independent of protein kinase A) and protein-tyrosine kinase-mediated pathways were found to play a role in the regulation of folic acid uptake by these cells. These results establish the suitability of NCM460 cells as an in vitro model system for investigating the details of the mechanism of colonic folate uptake and its regulation. Folic acid uptake by these cells appears to involve a carrier-mediated system, which is temperature-, pH-, and energy-dependent and appears to be under the regulation of cAMP and protein tyrosine kinase.
Thermal properties of beef cattle manure

Abstract The thermal conductivity of beef cattle manure was measured by a transient state method, while its specific heat was measured by a classical method of mixtures. The specific heat of beef cattle manure was found to decrease as Total Solids concentration (TS) increased, ranging from 4·13 kJkg−1 °C−1 at 1·42% TS to 1·400 kJkg−1 °C−1 at 99·4% TS. The thermal conductivity of beef cattle manure was found to range from 630mW m−1 °C−1 at 2·8% TS to 60· 4mW m−1 °C−1 at 95% TS. At low TS, the manure slurry's thermal conductivity was directly proportional to slurry density and decreased as TS increased. At a TS greater than 51%, the thermal conductivity was directly related to the manure's bulk density and was independent of the manure's TS. An equation relating the thermal conductivity of beef cattle manure to the volume fraction of void space in manure with TS greater than 51% is also given. In addition, results concerning the thermal diffusivity of beef cattle manure are presented.
Effects of nasal occlusion and oral contact on perception of metallic taste from metal salts

Iron and copper salts have complex olfactory and gustatory properties including a metallic flavor component that is decreased by nasal occlusion. To examine the sensory properties of ferrous sulfate and copper sulfate, a trained descriptive panel evaluated these compounds at equal molarity and perceived equal intensity with and without nasal occlusion. Ferrous sulfate exhibited a metallic taste and metallic aftertaste and copper sulfate exhibited a more pronounced metallic aftertaste. Metallic sensations were decreased by nasal occlusion, which in the absence of any orthonasal metallic smell, implies that the sensations were retronasally perceived volatiles in the nose open condition. Ferrous sulfate showed a larger effect of nasal occlusion. A second experiment isolated ferrous sulfate solutions from oral contact via a plastic barrier. In comparison to a condition in which oral contact was allowed, intensity ratings were decreased. This result is consistent with the hypothesis that rinses with solutions of metal salts, particularly ferrous sulfate, generate volatile lipid oxidation products in the mouth that are perceived retronasally as metallic flavors.
A Decision Tree-Based Classification Approach to Rule Extraction for Security Analysis

Stock selection rules are extensively utilized as the guideline to construct high performance stock portfolios. However, the predictive performance of the rules developed by some economic experts in the past has decreased dramatically for the current stock market. In this paper, C4.5 decision tree classification method was adopted to construct a model for stock prediction based on the fundamental stock data, from which a set of stock selection rules was derived. The experimental results showed that the generated rules have exceptional predictive performance. Moreover, it also demonstrated that the C4.5 decision tree classification model can work efficiently on the high noise stock data domain.
THE RATE OF VAPORIZATION OF DEUTERIUM OXIDE

Abstract The rate of vaporization of deuterium oxide was measured in the same apparatus used with ordinary water and described in an earlier paper. The experimental method is based on measurement of the pressure rise in a closed system during vaporization while simultaneously measuring the surface temperature. The condensation coefficient was found to be 0·0255 at about 4°C and 0·0212 at about 25°C. Within experimental error these values give the same temperature dependence found for H 2 O. As in the case of H 2 O, the values of α do not agree with the free angle ratio as estimated by the methods of K incaid and E yring and M ortensen and E yring . However, the isotope effect, α D 2 O /α H 2 O , as predicted by the free angle ratios, was in good agreement with the experimental value of 0·65.
Differential effects of prostaglandin synthetase inhibitors on EEG in rat

Abstract The effects of five nonsteriodal prostaglandin (PG) synthetase inhibitors on the electrocorticogram were studied in rats with chronically implanted supracortical electrodes. All of PG synthetase inhibitors produced high voltage activity in the electrocorticogram. However, behavior and spectral analysis of the electrocortical activity suggests that these drugs could be divided into two groups. Meclofenamic acid produced dose-related increases in excitation (to seizure) while ibuprofen, paracetamol and indomethacin produced dose-related increases in sedation.
THE TWO-AXIS METHOD: A NEW METHOD TO CALCULATE AVERAGE PRECIPITATION OVER A BASIN / La deux-axes méthode: une nouvelle méthode pour la calculation de la précipitation moyenne d'un bassin versant

Abstract The two-axis method, used to calculate average precipitation over a basin, is based on three assumptions inherent in the Thiessen and isohyetal methods. The method follows four steps: (1) The two axes of a basin are drawn following a standard procedure; (2) for each raingauge location a station angle is determined by either measuring or calculating the angle between lines connecting the station location to the farthest ends of the two axes; (3) each station is assigned a weight (the ratio of its angle to the sum of all station angles); (4) average area precipitation is calculated as the sum of the products of corresponding station weights and measured precipitation. The method is fast, efficient, and is readily computerized.
Detection and characterization of two ATP-dependent conformational changes in proteolytically inactive Escherichia coli Lon mutants by stopped flow kinetic techniques

Lon is an ATP dependent serine protease responsible for degrading denatured, oxidatively damaged and certain regulatory proteins in the cell. In this study we exploited the fluorescence properties of a dansylated peptide substrate (S4) and the intrinsic Trp residues in Lon to monitor peptide interacting with the enzyme. We generated two proteolytically inactive Lon mutants, S679A and S679W, where the active site serine is mutated to an Ala and Trp residue, respectively. Stopped-flow fluorescence spectroscopy was used to identify key enzyme intermediates generated along the reaction pathway prior to peptide hydrolysis. A two-step peptide binding event is detected in both mutants, where a conformational change occurs after a rapid equilibrium peptide binding step. The Kd for the initial peptide binding step determined by kinetic and equilibrium binding techniques is approximately 164 micromolar and 38 micromolar, respectively. The rate constants for the conformational change detected in the S679A and S679W Lon mutants are 0.74 +/- 0.10 s(-1) and 0.57 +/- 0.10 s(-1), respectively. These values are comparable to the lag rate constant determined for peptide hydrolysis (klag approximately 1 s(-1)) [Vineyard, D., et al. (2005) Biochemistry 45, 4602-4610]. Replacement of the active site Ser with Trp (S679W) allows for the detection of an ATP-dependent conformational change within the proteolytic site. The rate constant for this conformational change is 7.6 +/- 1.0 s(-1), and is essentially identical to the burst rate constant determined for ATP hydrolysis under comparable reaction conditions. Collectively, these kinetic data support a mechanism by which the binding of ATP to an allosteric site on Lon activates the proteolytic site. In this model, the energy derived from the binding of ATP minimally supports peptide cleavage by allowing peptide substrate access to the proteolytic site. However, the kinetics of peptide cleavage are enhanced by the hydrolysis of ATP.
Silicon based microstructures suitable for intracortical electrical stimulation (visual prosthesis application)

The authors have produced a 0.4-mm*0.4-mm*1.6-mm, three-dimensional, silicon-based microstructure which can be used for stimulation of cortical neurons. The structure consists of 100 pyramidal-shaped needles, each 1.5 mm long with a base about 0.06 mm on a side. The entire structure is passivated with silicon nitride except for the tips of the needles, which are coated with platinum. The mechanical properties of these structures and the tissue reaction to them were studied in cat cortex. Impact insertion of the arrays produces good implantation with minimal tissue insult. Preliminary histological studies suggest that cortical tissues are not adversely affected by these microstructures. >
Comparison of perturbative RG theory with lattice data for the 4d Ising model

Abstract Predictions for ( ϕ 4 ) 4 theory from renormalization-group-improved perturbation theory, as formulated by Luscher and Weisz, are compared to published (and some unpublished) data from lattice Monte Carlo simulations of the 4-dimensional Ising model. Good agreement is found in all but one respect: the change in the wavefunction-renormalization constant Z ˆ R across the phase transition is significantly greater than predicted. A related observation is that propagator data in the broken phase show deviations from free-propagator form—deviations that become larger, not smaller, closer to the continuum limit. More data closer to the critical point are needed to clarify the situation.
Stability in a class of cyclic epidemic models with delay

A detailed analysis of a general class of SIRS epidemic models is given. Sufficient conditions are derived which guarantee the global stability of the endemic equilibrium solution. Further conditions are found which ensure instability for the equilibrium. Finally, the dependence of the stability on the contact number and the ratio of the mean length of infection to the mean removed time is considered.
Neutronic characteristics of linear-assembly breed-and-burn reactors

Abstract Linear-assembly breed-and-burn (B&B) reactors are B&B reactors that use axially connected assemblies similar to conventional LWR or fast reactor fuel assemblies. Methods for analyzing linear-assembly B&B reactors and their fuel cycles are developed and applied. General neutronic characteristics of linear-assembly B&B reactors are analyzed, including the effects that burnup, shuffling sequence, and radial and axial size have on equilibrium-cycle k-effective. The mechanisms that give rise to a highly peaked axial burnup distribution are explained, and a method for predicting peak burnup vs. k-effective based on infinite-medium depletion calculations is developed. Next, the neutron excess concept from previous studies of B&B reactors is extended to apply to linear-assembly B&B reactors, which allows the amount of starter fuel needed to establish a given equilibrium cycle to be calculated. Several example applications of the neutron excess formulation are given. First, an example model of a linear-assembly B&B reactor is analyzed to find the neutron excess cost of an equilibrium cycle. Second, simple one-dimensional models are used to predict the neutron excess value obtainable from different starter fuel configurations. Finally, these ideas are applied to design a fuel cycle consisting of linear-assembly B&B reactors and fuel recycling via a melt refining process. The neutron excess concept is used to design an appropriate starter fuel configuration made from melt refined fuel, which is then used in a transition model that shows how the desired equilibrium cycle can be established. The doubling time of this fuel cycle is calculated as an example of what is achievable using B&B reactors.
Sympathetic neural responses to induced ventricular tachycardia

Abstract Although sympathetic mechanisms play a major role in buffering abrupt arterial pressure reductions, including those that occur during tachyarrhythmias, human sympathetic nervous system responses to ventricular tachycardia have not been measured. Muscle sympathetic nerve activity was recorded directly from the peroneal nerve in 16 patients during diagnostic induction of 19 episodes of sustained monomorphic ventricular tachycardia (average rate 189 beats/min, range 130 to 250). Average systolic and diastolic pressures decreased from 149/78 to 61/49 mm Hg by 10 s and increased toward baseline levels to 88/64 mm Hg by 1 min of ventricular tachycardia. Average sympathetic nerve activity increased by 92% at 10 s in direct proportion to arterial pressure reductions and in inverse proportion to ventricular rate and remained 83% above baseline levels at 1 min. The late recovery of arterial pressure during ventricular tachycardia was related significantly to the magnitude of early sympathetic responses. Sympathetic activity tended to lose its discrete bursting pattern during ventricular tachycardia, and power spectral analysis showed that the large sympathetic peaks at the heart rate frequency present during sinus rhythm are absent during ventricular tachycardia. This study is the first to delineate human sympathetic nervous system responses to ventricular tachycardia. The results suggest that in the patients studied, large early sympathetic surges differed from those that occur during sinus rhythm and contributed to hemodynamic stability during ventricular tachycardia.
Physiology: Inflammation links ageing to the brain

Inflammation-activated signalling pathways in the brain's hypothalamus control the production of ageing-related hormones. This finding provides a link between inflammation, stress responses and systemic ageing. See Article p.211 Ageing is closely associated with both nutrition and inflammation, and certain neurons can mediate environmental influences on ageing in Caenorhabditis elegans and Drosophila. This study focuses on the hypothalamus, a brain region that is critical for the neuroendocrine interaction between the central nervous system and the periphery. Guo Zhang et al. show that activation of IKK-β and NF-κB in the hypothalamus of mice accelerates the ageing process and shortens lifespan. Inhibition of IKK-β and NF-κB, mediators of metabolic inflammation, delays ageing and extends lifespan. NF-κB activation results in a decline of gonadotropin-releasing hormone (GnRH) levels and suppresses neurogenesis. GnRH treatment amends ageing-impaired neurogenesis and decelerates ageing. These results suggest that NF-κB-mediated inhibition of GnRH may shut down reproduction and ensure the quality of the species, but it initiates systemic ageing at the same time.
β-Endorphin in pituitary intraglandular colloid of intermediate lobe origin

Abstract Radioimmunoassay (RIA) detected the presence of β-endorphin in the intraglandular colloid (IGC) of bovine pituitary intermediate lobe origin. The amount of β-endorphin recovered in each of twelve samples ranged from 0.15 to 218.30 pmol/mg protein. A second group of assays [amino acid analysis, high performance liquid chromatography (HPLC) and mass spectral analysis] confirmed the RIA findings in another series of colloid samples. Approximately 75 pmol was collected from eight pooled glands. β-Endorphin is an addition to the list of peptide hormones (e.g., methionine-enkephalin, adrenocorticotropin, arginine-vasopressin, α-melanocyte-stimulating hormone, β-lipotropin and somatostatin) previously discovered in IGC by this laboratory.
Identification of active antiviral compounds against a New York isolate of West Nile virus

The recent West Nile virus (WNV) outbreak in the United States has increased the need to identify effective therapies for this disease. A chemotherapeutic approach may be a reasonable strategy because the virus infection is typically not chronic and antiviral drugs have been identified to be effective in vitro against other flaviviruses. A panel of 34 substances was tested against infection of a recent New York isolate of WNV in Vero cells and active compounds were also evaluated in MA-104 cells. Some of these compounds were also evaluated in Vero cells against the 1937 Uganda isolate of the WNV. Six compounds were identified to be effective against virus-induced CPE with 50% effective concentrations (EC50) less than 10 μg/ml and with a selectivity index (SI) of greater than 10. Known inhibitors of orotidine monophosphate decarboxylase and inosine monophosphate dehydrogenase involved in the synthesis of GTP, UTP, and TTP were most effective. The compounds 6-azauridine, 6-azauridine triacetate, cyclopententylcytosine (CPE-C), mycophenolic acid and pyrazofurin appeared to have the greatest activities against the New York isolate, followed by 2-thio-6-azauridine. Anti-WNV activity of 6-azauridine was confirmed by virus yield reduction assay when the assay was performed 2 days after initial infection in Vero cells. The neutral red assay mean EC50 of ribavirin was only 106 μg/ml with a mean SI of 9.4 against the New York isolate and only slightly more effective against the Uganda isolate. There were some differences in the drug sensitivities of the New York and Uganda isolates, but when comparisons were made by categorizing drugs according to their modes of action, similarities of activities between the two isolates were identified.
Expert system development and testing: a knowledge engineer's perspective

Abstract This article discusses the problems found in the validation and verification of a knowledge-based system for equity selection. These problems include the selection of test data, poor methodology, and the difficulties associated with using prototypes. The article then examines the possible techniques available to the knowledge engineer for improving validation and verification. The article discusses exhaustive testing, case-based testing, formal specifications, functional programming, critical testing, mutation testing, and reliability. Finally the article discusses the approach that the knowledge engineer would take in rewriting the equity selection system, one based on a rigorous development methodology that uses as many formal validation techniques as possible to raise the quality of the software produced.
Regulation of cyclic peptide biosynthesis and pathogenicity in Cochliobolus carbonum by TOXEp, a novel protein with a bZIP basic DNA-binding motif and four ankyrin repeats.

HC-toxin is an epoxide-containing cyclic tetrapeptide that is a critical virulence determinant in the pathogenic interaction between the filamentous fungus Cochliobolus carbonum and maize. HC-toxin exerts a potent cytostatic effect on plant and animal cells by inhibiting histone deacetylase. The biosynthesis of HC-toxin by C. carbonum is controlled by a complex genetic locus, TOX2, that contains multiple, duplicated copies of genes encoding export and biosynthetic enzymes. A new gene in the TOX2 complex, TOXE, has now been isolated. Mutation of TOXE by targeted gene disruption has no effect on growth and sporulation but abolishes HC-toxin production and pathogenicity. TOXE is required for the expression of three genes with a known or putative role in HC-toxin production, but is not required for expression of HTS1, which encodes the large, multifunctional peptide synthetase that is the central enzyme in HC-toxin biosynthesis. At its N-terminus, TOXEp has a bZIP basic DNA binding domain, but it does not contain any discernible leucine zipper or helix-loop-helix. At its carboxy terminus, TOXEp contains four ankyrin repeats. In having these two common regulatory motifs in a single polypeptide, TOXEp appears to represent a novel class of regulatory protein. TOXE is present only in HC-toxin-producing (Tox2+) isolates of C. carbonum. Most Tox2+ isolates have two copies; in strain SB111, one copy of TOXE is on the same 3.5-Mb chromosome that contains all of the other genes known to be involved in HC-toxin biosynthesis, and the second copy of TOXE is on a 0.7-Mb chromosome.
Community and individual reaction to environmental hazards: Developing a measurement technology

This study was an attempt to develop an efficient method of monitoring and assessing how members of a community react to a toxic hazard in their community. The intent was to develop a short instrument which could be applied in multiple settings, or in the same setting several times. The methodology was a short questionnaire that addressed six issues: sources of information about the hazard, beliefs about justice and responsibility, beliefs about why the hazard is a problem, extent of active concern, involvement in community affairs, and satisfaction with life. A mailed questionnaire was developed and tested in a community near an EPA Superfund site in the United States. Results of the effort are discussed relative to the particular community studied, and relative to furthering the assessment technology begun in this research.
16 A Novel Approach to “See One, Do One”: Multimedia Presentations before Procedure Workshops and Simulation

We propose that residents and medical students are likely to gain more from a simulation experience or procedure workshop if they are given educational materials conveying key concepts to review beforehand. Several multimedia formats are available to accomplish this task. Digital video and Powerpoint presentations can be converted to podcasts with or without audio tracks using programs like Profcast, GarageBand, Camtasia, and Keynote. There are also procedure videos available from sources like the New England Journal of Medicine. Participants are provided these instructional materials via a secure web server or email attachment several days prior to the educational session. These presentations are kept short in length (no greater than 10-15 minutes) to optimize compliance while delivering information efficiently. They can be reviewed at the learner's convenience on a personal computer or on an iPod with video capability. This method can significantly reduce the time required for didactic teaching in a procedure workshop; for example, when medical students review a video on basic suturing before attending a suturing workshop, they are prepared to begin practicing with minimal initial instruction. Furthermore, conveying the same information repeatedly through different instructional methods can help learners consolidate knowledge, as in the case of a presentation provided to residents before a simulation session containing the basic clinical teaching points of the case. Participant feedback regarding these resources has been favorable.
Conflict Resolution Between Friends During Middle Childhood

The author interviewed 74 children (ages 8.5-11.5 years) in an exploratory study of interpersonal conflict resolution between children. Results suggest that children (a) most frequently used assertion and discussion as conflict resolution strategies, (b) used more than one strategy in a single conflict, and (c) used a strategy that corresponded to the strategy used by the other child in the conflict. The author discusses the implications of the findings and suggests areas for future research.
Parallel Generation of Postfix and Tree Forms

Abstract : Efficient parallel algorithms to obtain the postfix and tree forms of an infix arithmetic expression are developed. The shared memory model of parallel computing is used. (Author)
Long-Term Outcome of Hypnotic-Analgesia Treatment for Chronic Pain in Persons with Disabilities

Data from 26 participants in a case series of hypnotic analgesia for chronic pain were examined to determine the long-term effects of hypnosis treatment. Statistically significant decreases in average daily pain intensity, relative to pretreatment values, were observed at posttreatment and at 3- and 9-month follow-up but not at 6- or 12-month follow-up. The percent of participants who reported clinically meaningful decreases in pain were 27%, 19%, 19%, and 23%, at the 3-, 6-, 9-, and 12-month follow-up points, respectively. Moreover, at 12-months posttreatment, 81% of the sample reported that they still used the self-hypnosis skills learned in treatment. Overall, the results indicate that about 20% of the sample obtained substantial and lasting long-term reductions in average daily pain following hypnosis treatment and that many more continue to use self-hypnosis up to 12 months following treatment.
A gear iterator

Abstract A computer program has been written which fits the rate constants of a chemical reaction network to experimental data. The program accepts data in many coordinate systems. Both plots and statistical analyses can be obtained.
Modeling and measurement of film deposition in a one-dimensional hot-wire CVD system

Abstract A novel hot-wire chemical vapor deposition (HW-CVD) geometry was employed to study the deposition of Teflon-like films from hexafluoropropylene oxide (HFPO). In this configuration hot wires were replaced by thin ribbons, and under proper operating conditions the complex HW-CVD geometry is simplified to a one-dimensional system. The kinetics of both HFPO decomposition and Teflon deposition were measured as a function of operating conditions. A hybrid 2-D CFD/1-D stagnation flow model was used to interpret the results. At relatively low ribbon temperatures good agreement between model and experiment was observed. Deviations observed at higher ribbon temperatures were attributed to gas-phase polymerization of CF 2 moieties, and participation of these oligomers in the deposition process.
Approximating likelihoods for large spatial data sets

Summary. Likelihood methods are often difficult to use with large, irregularly sited spatial data sets, owing to the computational burden. Even for Gaussian models, exact calculations of the likelihood for n observations require O(n3) operations. Since any joint density can be written as a product of conditional densities based on some ordering of the observations, one way to lessen the computations is to condition on only some of the ‘past’ observations when computing the conditional densities. We show how this approach can be adapted to approximate the restricted likelihood and we demonstrate how an estimating equations approach allows us to judge the efficacy of the resulting approximation. Previous work has suggested conditioning on those past observations that are closest to the observation whose conditional density we are approximating. Through theoretical, numerical and practical examples, we show that there can often be considerable benefit in conditioning on some distant observations as well.
Inverse heat transfer analysis of Bridgman crystal growth

The effects of asymmetry in furnace temperature profile and pulling velocity on the crystal interface shape are demonstrated while neglecting the latent heat of solidification. It is seen that the furnace temperature profile may be varied in order to influence the shape of the melt-crystal interface. An exact thermal analysis is then performed on the Bridgman technique by including the latent heat of solidification as a source term. The exact temperature field required for yielding a flat melt-crystal interface is obtained. The earlier observation regarding the influence of furnace temperature profile on the interface shape is confirmed and a criterion for achieving a flat interface is obtained. Various furnace temperature profiles are selected and their corresponding melt-crystal interface results are presented.
How cultural difference affects international tourism public relations websites: A comparative analysis using Hofstede's cultural dimensions

Abstract This research aims to employ Hofstede's cultural dimensions as a frame to identify valid explanatory factors that account for differences in countries’ tourism websites. The study results support that Hofstede's cultural dimensions can be a valuable tool for developing public relations strategies conducive to building and maintaining relationships with multicultural audiences.
3D Anatomical Investigation of Achilles Tendon Using a Freehand Ultrasound Imaging System

The Achilles tendon plays an important role in our daily activities and studies have shown that tendon properties, such as morphology and stiffness, are related to aging, activity levels and genders. A better understanding of its morphology and mechanical properties will provide guidance to health professionals on intervention recommendation. However, the majority of the existing studies investigated muscle tendon in a single plane and there is a lack of consistent method for 3D anatomical investigation. The objective of this study is to setup a 3D freehand ultrasound imaging system and investigate in vivo 3D Achilles tendon structure in anatomical reference frame. A GE ultrasound machine with motion sensor was used to obtain 3D structure of the Achilles tendon. The ultrasound images were segmented and the digitized points were transformed into the anatomical reference frame. The point cloud data were further meshed using triangulation and smoothed using NURBS. The 3D surface was sliced with horizontal planes to obtain the tendon girth and cross-sectional area as a function of tendon length. The results agree well with previous studies and demonstrate the feasibility of applying this system in the clinical sites.