cssi/SciSciGPT-SciSciNet huggingface dataset:
Alpha1 connexin 43 gap junctions are decreased in human adrenocortical tumors.

Gap junctional communication disorders have been implicated in the etiology of benign and malignant tumors. Understanding the type, distribution, and frequency of gap junctions in adrenal disorders should provide insight into the role of gap junctions in adrenal carcinogenesis as well as information that may be useful in developing improved diagnosis and treatment of adrenal diseases. Using immunocytochemical techniques, we have characterized and comparedα 1 connexins 43 gap junction protein levels in normal adrenal glands to those in benign and malignant adrenocortical human tumors. In addition, gap junction protein levels were studied in a human adrenal cancer cell line (H295). In both normal and neoplastic adrenal tissues, only α1 connexin 43 could be detected, whereas β1 connexin 32 and β2 connexin 26 were not found. In the normal adrenal gland, the zona fasciculata was demonstrated to have the highest number of gap junctions per cell (mean ± sem, 13.78 ± 1.93). In contrast, in benign adrenocortical a...
Convergence of a large time step generalization of Godunov's method for conservation laws

A natural generalization of Godunov's method for Courant numbers larger than 1 is obtained by handling interactions between neighboring Riemann problems linearly, i.e., by allowing waves to pass through one another with no change in strength or speed. This method is well defined for arbitrarily large Courant numbers and can be written in conservation form. It follows that if a sequence of approximations converges to a limit u(x,t) as the mesh is refined, then u is a weak solution to the system of conservation laws. For scalar problems the method is total variation diminishing and every sequence contains a convergent subsequence. It is conjectured that in fact every sequence converges to the (unique) entropy solution provided the correct entropy solution is used for each Riemann problem. If the true Riemann solutions are replaced by approximate Riemann solutions which are consistent with the conservation law, then the above convergence results for general systems continue to hold.
Solution Processable n-Type Perylene Diimide Copolymers for Organic Photovoltaics

Perylene diimides are known as promising n-type semiconductor building blocks. Here we report the synthesis and characterization of a set of three soluble poly(perylene diimide)s and their preliminary characterization in organic photovoltaic cells. These polymers are made through the polycondensation of perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) with a variety of poly(ethylene glycol) (PEG)- or poly(propylene glycol) (PPG)-based diamine comonomers. The flexible spacer offers increased solubility in organic solvents and allows the perylene core to assume a conformation that promotes favorable cofacial {pi}-{pi} interactions. Mixtures of these polymers with the hole-transporting polymer, poly(3-hexylthiophene) (P3HT) result in significant fluorescence quenching. However, the phase separation occurs on a scale too large for a bulk heterojunction solar cell. The PPGylated poly(perylene diimide) shows an unusually low free electron concentration ({approx}1.0 x 10{sup 12} cm{sup -3}) and therefore makes an excellent model system for future doping studies. These new polymers may have promise as stable electron-conductive layers with large light-absorptivities in solution-processable applications of organic electronics.
Classroom Note: Hoffman's Circle Untangled

In 1951, Alan J. Hoffman provided the first example that demonstrated that Dantzig's simplex method for linear programming can cycle (unless special precautions are taken). This paper describes a geometry for understanding Hoffman's example---something that has been lacking for over two-fifths of a century.
Application of backscattered electron images to the study of fracture in glass ceramics

Fracture surfaces of three different glass ceramics were examined to determine the critical flaw sizes and the corresponding microstructures of the materials directly from the fracture surfaces. Standard secondary electron (SE) images and classical topographical back-scattered electron (BSE) images were used to measure the critical flaw sizes and to observe deviations of the critical flaw interfaces from smooth elliptical fronts. Compositional BSE images were used to characterize the microstructures in and around the critical flaws directly from the unetched fracture surfaces. A direct correlation was found between the critical flaw size and microstructural units effectively acting as grains within the flaw and the fracture toughness. This relationship enabled the discrepancies between the calculated fracture toughness and the measured fracture toughness to be resolved.
Abstract LB-278: BRMS1 promoter methylation correlates with decreased expression of BRMS1 in non-small cell lung cancer

Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC Background: Breast cancer metastasis suppressor gene-1 (BRMS1) mRNA and protein expression are significantly decreased in non-small cell lung cancer (NSCLC) cell lines and human NSCLC when compared to normal bronchial epithelial cells and adjacent noncancerous tumor tissue, respectively. We hypothesized that one mechanism through which BRMS1 expression was decreased in NSCLC was through BRMS1 promoter methylation. Materials and Methods: Human NSCLC BRMS1 promoter methylation was evaluated using methylation-specific PCR and bisulfite sequencing. The effect of methylation on BRMS1 mRNA and protein expression was assessed following treatment with 5-azacitidine, a demethylating agent in NSCLC cell lines. BRMS1 transcriptional activity was assessed using a human BRMS1-luc reporter gene construct cloned by our group. Student's T-Test and Chi-square tests were used to determine significance between variables of two patient populations separated based on tumor histology (squamous cell or adenocarcinoma) and to evaluate the methylation profile between the two tumor histologies. Immunohistochemical analysis for BRMS1 protein was performed on both tumor and adjacent noncancerous bronchial epithelium. A general linear model tested the association between BRMS1 promoter methylation in human NSCLC and specific clinical and histopathologic variables. Results: The BRMS1 promoter region contains a CpG island that was hypermethylated in all NSCLC cell lines and human tumors. This strongly correlated with reduced BRMS1 promoter activity. NSCLC cell lines treated with 5-azacitidine showed a robust recovery of BRMS1 mRNA and protein levels, suggesting that promoter methylation is involved in BRMS1 transcriptional regulation. Analysis of 40 patient NSCLC samples (20 adenocarcinoma and 20 squamous cell) identified a significant increase in the amount of BRMS1 promoter methylation when comparing tumor specimen to adjacent noncancerous tissue for both tumor histologies (p<0.0001). Additionally, the BRMS1 promoter region was significantly more methylated in squamous cell compared to adenocarcinoma histology (p=0.01). Subsequent immunohistochemical analysis confirmed a correlation between BRMS1 promoter methylation and decreased bronchial epithelium BRMS1 protein expression (p=0.06). Moreover, in the squamous cell histology, pathologic tumor stage was associated with elevated BRMS1 methylation (p=0.04). Conclusions: These studies identify BRMS1 promoter methylation as an important mechanism for silencing BRMS1 expression in NSCLC and highlight the potential clinical relevance of this epigenetic signature with respect to tumor histology and stage. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr LB-278.
Occupational exposures and lung cancer: Adjustment for unmeasured confounding by smoking

Background: Occupational cohort mortality studies rarely include information on smoking history. Consequently, smoking is often an unmeasured potential confounder in analyses of associations between occupational exposures and lung cancer. Several authors have recommended sensitivity analyses to assess confounding by smoking, which require speculation about the prevalence of smokers in different occupational exposure groups. Methods: A method of adjustment for confounding by smoking is proposed in which the target parameter of interest (the log hazard ratio for lung cancer contrasting exposed to unexposed workers, adjusted for smoking) is approximated by the difference between the crude exposure-disease associations for lung cancer and chronic obstructive pulmonary disease. A polytomous logistic regression method is used to derive appropriate confidence intervals. The performance of this adjustment approach is assessed via direct calculations. Results: Under the scenarios considered, 90% or more of the bias due to confounding by smoking was removed via this adjustment in the absence of smoking data. Conclusions: This approach to adjustment for confounding by smoking can be employed without explicitly positing the distribution of smoking with respect to occupational exposure. The approach is easily implemented in analyses of occupational cohort data and should facilitate quantitative assessments of bias due to unmeasured confounding by smoking in occupational studies of lung cancer.
Use of a Hinged Antibiotic-Loaded Cement Spacer for an Infected Periprosthetic Fracture in a Total Elbow Arthroplasty: A Novel Construct Utilizing Ilizarov Rods: A Case Report.

Case: After a fall, a seventy-seven-year-old woman had been treated at an outside institution with a right total elbow arthroplasty (TEA), which was complicated by subsequent infection and a periprosthetic fracture. After referral to our institution for definitive management, we confirmed chronic periprosthetic infection. The patient underwent a two-stage revision with interval use of a hinged antibiotic-loaded cement spacer created with Ilizarov rods. One year postrevision, she had no pain, no signs of infection, and an elbow active range of motion of 10° to 110°. Conclusion: A two-stage revision of an infected TEA with a periprosthetic fracture can be managed successfully with our novel hinged antibiotic-loaded cement spacer.
Gate-Voltage Studies of Discrete Electronic States in Aluminum Nanoparticles

We have investigated the spectrum of discrete electronic states in single, nm-scale Al particles incorporated into new tunneling transistors, complete with a gate electrode. The addition of the gate has allowed (a) measurements of the electronic spectra for different numbers of electrons in the same particle, (b) greatly improved resolution and qualitatively new results for spectra within superconducting particles, and (c) detailed studies of the gate-voltage dependence of the resonance level widths, which have directly demonstrated the effects of nonequilibrium excitations.
Approximate global symmetries of the electroweak interactions

Abstract We discuss and exemplify a simple explanation for the approximate symmetries of the electroweak interactions that arises naturally in models in which the quarks, leptons and Higgs particles are all composite states of strongly interacting fermions.
The spontaneous emission factor for lasers with gain induced waveguiding

The expression for the spontaneous emission factor for lasers with gain induced waveguiding has a factor K , called by Petermann "the astigmatism parameter." This factor has been invoked to explain spectral and dynamic characteristics of this class of lasers. We contend that the widely accepted form of the K factor is based on a derivation which is not appropriate for the typical laser situation where the spontaneous emission factor is much smaller than unity. An alternative derivation is presented which leads to a different form for the K factor, The new expression predicts much smaller values under conditions where the previous theory gave values large compared to unity. Petermann's form for the K factor is shown to be relevant to large gain linear amplifiers where the power output is amplified spontaneous emission noise. The expression for the power output has Petermann's value of K as a factor. The difference in the two situations is that in the laser oscillator the typical atom of interest couples a small portion of its incoherent spontaneous emission into the dominant mode, whereas in the amplifier only the atoms at the input end are important as sources and their output is converted to a greater degree into the dominant mode through the propagation process. In our analysis we use a classical model of radiating point dipoles in a continuous medium characterized by a complex permittivity. Since uncritical use of this model will lead to infinite radiation resistance we address the problem of its self-consistency.
Revision of the genus Clibadium (Asteraceae, Heliantheae)

Abstract Revision of the genus Clibadium (Asteraceae, Heliantheae). Brittonia 55: 245–301. 2003.—Clibadium L. (Asteraceae, Heliantheae) is a genus of 29 species distributed throughout Latin America, from Mexico to Peru, and in the West Indies, with high numbers of species in Costa Rica, Colombia, and Ecuador. Clibadium includes shrubs and small trees; usually with loosely aggregated capitula; herbaceous phyllaries arranged in 1–5 series; receptacles usually paleaceous throughout; corollas of pistillate florets 2–4-lobed; corollas of the staminate florets 4–5-lobed; purple to black anthers; and chromosome numbers all n = 16. Two sections of species previously recognized are here considered as subgenera (subg. Paleata and subg. Clibadium) containing two and four sections, respectively. Clibadium subg. Paleata contains five species distributed in sects. Eggersia (3 spp.) and Trixidium (2 spp.), and subg. Clibadium has 24 species distributed among sects. Clibadium (6 spp.), Glomerata (9 spp.), Grandifolia (5 ...
Metabolism and Bioactivation of 3-Methylindole by Clara Cells, Alveolar Macrophages, and Subcellular Fractions from Rabbit Lungs

3-Methylindole (3MI), a fermentation product of tryptophan produced by intestinal and ruminal microflora, has been shown to cause pneumotoxicity in several species subsequent to cytochrome P450-mediated biotransformation. Among several species studied, rabbits are comparatively resistant to 3MI-induced pneumotoxicity, especially when compared to goats or mice. In this study, rabbit pulmonary cells and subcellular fractions were used to examine the metabolism and bioactivation of 3MI. A covalent-binding metabolite was produced in 3MI incubations by both Clara cells and macrophages. The addition of the cytochrome P450 inhibitor, 1-aminobenzotriazole, to these incubations inhibited the production of covalent-binding metabolite(s) by 94% in Clara cells and only 24% in macrophages. In incubations of Clara cells or macrophages with 3MI and N-acetylcysteine (NAC), a polar conjugate was detected and tentatively identified as an adduct of 3-hydroxy-3-methylindolenine (3H3MIN). Also identified were 3[(N-glutathione-S-yl)-methyl]-indole (3MI-GSH) and 3-methyloxindole (3MOI). In rabbit lung microsomal incubations with 3MI and glutathione (GSH), 3MI-GSH, 3MOI, indole-3-carbinol, and a GSH adduct of 3H3MIN were identified. The addition of cytosol to the microsomal incubations with GSH did not increase the rate of formation of the GSH adducts, indicating that cytosolic GSH-S-transferases are not essential in the formation of these metabolites. GSH significantly decreased the covalent binding of an electrophilic metabolite in microsomal incubations. These data suggest that GSH may be important in the mitigation of 3MI toxicity. Furthermore, the comparison of 3MI bioactivation to electrophilic intermediates in Clara cells and alveolar macrophages suggests that 3MI is metabolized by different oxidative pathways in the two different cell types, although the same metabolites were produced by the two cell types. This study shows that rabbit pulmonary enzymes are capable of bioactivating 3MI to reactive intermediates which become covalently bound to cellular macromolecules. This indicates that the relative resistance of rabbits to 3MI-induced pneumotoxicity is probably not due to differences in metabolic enzymes which convert 3MI to reactive intermediates.
A New Controlled-Environment Cell for Photodegradation Studies of Metal-Backed Polymer Films Using FT-IR Reflection Absorbance Spectroscopy

Polymer films are being used for photovoltaic solar energy conversion systems and also to protect mirror surfaces from exposure to environmental degradation (ultraviolet light, temperature, moisture, and atmospheric gases). Understanding of the photodegradation mechanisms of metal-backed films is of importance for their effective utilization in such applications.
Regional comparison of tumor vascularity and permeability parameters measured by albumin‐GD‐DTPA and GD‐DTPA

Sequential albumin-Gd-DTPA and Gd-DTPA dynamic enhancement studies were performed in an animal tumor model for the comparison of regional vascularity and permeability parameters measured by these two different sizes of contrast agents. The early albumin-Gd-DTPA enhancement arises from the vascular compartment, and the averaged signal enhancement derived from the first 3 to first 6 images postinjection can be reliably used to assess vascularity. The signal intensity in the images during the period of 5-10 min post-albumin-Gd-DTPA injection shows a steady linear variation. The intercept of the linear relationship is another indicator of the vascularity and the slope represents the tumor permeability to albumin-Gd-DTPA. The Gd-DTPA enhancement study was analyzed by a two-compartmental pharmacokinetic model to calculate the regional vascularity and permeability. The permeability parameters measured from albumin-Gd-DTPA and Gd-DTPA show an excellent correlation. The vascularity parameters measured from albumin-Gd-DTPA show good linear correlation with the low vascularity groups measured by Gd-DTPA, but show saturation for the high vascularity groups. The enhancement mechanisms for both contrast agents are discussed to relate the imaging parameters to the physiological variables.
Lithium in the most extreme halo stars; trends with metallicity

A grid of extremely metal-poor stellar evolutionary tracks (Z = 0.00001) is constructed to compare the predicted lithium abundance depletion to observations of the lithium abundance in correspondingly metal-poor stars (Fe/H = -3.3), and, combined with an earlier work to investigate trends of lithium isochrones with metal abundance. Lithium abundances in the most extreme halo stars hint at the possibility of small downward slope toward lower T(eff) in the flat Li-T(eff) relation (the Spite lithium plateau) observed in slightly less extreme stars; the models also predict this. In the cool star region of the Li-T(eff) plane, higher metallicity lithium isochromes are cooler at fixed lithium abundance, consistent with the observations. Current data thus agree well with the lithium trends from standard model.
Role of α-helical conformation of histatin-5 in candidacidal activity examined by proline variants

Human salivary histatin-5 (Hsn-5) is a potent in vitro anticandidal agent. The aim of this study was to investigate the importance of alpha-helical structure of Hsn-5 for its candidacidal activity. The following three Hsn-5 variants, where one or more functionally nonessential residues were replaced with proline (potent alpha-helix breaker), were produced by Escherichia coli expression system: H21P (1P), H19P/H21P (2P), and E16P/H19P/H21P (3P). The activities of purified proteins were determined by candidacidal assays, and the secondary structures by circular dichroism (CD) spectroscopy in trifluoroethanol (TFE) that is considered the helix-promoting solvent, and lysophosphatidyl-glycerol (LPG) micelles, the environment that more closely resembles the biological membranes. Our results indicated that 3P variant displayed a candidacidal activity which was similar to that of unaltered Hsn-5 (0P), while 1P and 2P variants showed lower cidal activity. The CD spectra in TFE indicated that 3P variant has less helical characteristics than the 0P, 1P and 2P. These results suggested that the alpha-helical content of Hsn-5 proline variants does not correlate with the candidacidal activity. Further, the CD spectral analysis of peptides in LPG micelles indicated the formation of beta-turn structures in 0P and 3P variants. In conclusion, 3P variant which exhibited comparable candidacidal activity to 0P contains lower percentage of alpha-helical structure than 1P and 2P variants, which exhibited lower candidacidal activity. This suggests alpha-helix may not be important for anticandidal activity of Hsn-5.
SOFC performance with Fe-Cr-Mn alloy interconnect

The performance of anode-supported SOFC’s utilizing a Mn-containing ferritic stainless steel (Crofer22 APU) as the cathode current collector were assessed. Three cathodes were considered: (La0.8Sr0.2)0.99MnO3, (La0.8Sr0.2)0.99FeO3and (La0.6Sr0.4)0.98Fe0.8C00.2O3 (all samples incorporated a Sm-doped CeO2 interlayer between the cathode and the thin film YSZ electrolyte). Inclusion of the Fe-Cr alloy caused rapid degradation in all samples, which was attributed to solid-state reactivity at the cathode-Crofer interface, in addition to Cr volatilization from the alloy and subsequent condensation/reaction within the cathode and at the cathode-electrolyte interface. In situ- HTXRD was used to access the cathode-Crofer reaction products. Pre-oxidation of the Crofer at 800 degrees C for 500 hours to form a protective (Mn,Cr)3O4 spinel coating resulted in a marginal reduction of the cell degradation rate.
An evaluation of the accuracy of residency applicants' curricula vitae: Are the claims of publications erroneous?

Abstract Competition for residency positions in dermatology is intense. Training programs in other disciplines have described significant misrepresentation among their applicants in claims of research and publication. An evaluation was made of the curricula vitae for the 138 applicants with completed applications for our 1994 residency match. Cited articles were placed in four categories: "published," "in print/in press," "submitted for publication," and "in preparation/in progress." We found significantly less misrepresentation than has been described in other specialty training programs. Simplification of the way in which applicants verify their bibliography may reduce erroneous citations and remove implications of willful misrepresentation of academic achievements.
Salinity tolerance of the invasive round goby: Experimental implications for seawater ballast exchange and spread to North American estuaries

Abstract The Eurasian round goby ( Neogobius melanostomus ) invaded the freshwater North American Great Lakes in ~ 1990 via accidental introduction from ballast water discharge. Its genotypes in the Great Lakes traced to estuaries in the northern Black Sea, where the round goby flourishes in a variety of salinities to 22 parts per thousand (ppt). To prevent further introductions, U.S. and Canadian Coast Guard regulations now require that vessels exchange ballast water at sea before entering the Great Lakes. Since salinity tolerance of the invasive round goby population is poorly understood, we tested 230 laboratory-acclimated fish in three experimental scenarios: (1) rapid salinity increases (0–40 ppt), simulating ballast water exchange, (2) step-wise salinity increases, as during estuarine tidal fluxes or migration from fresh to saltwater, and (3) long-term survivorship and growth (to 4 months) at acclimated salinities. Almost all gobies survived experiments at 0–20 ppt, whereas none survived ≥ 30 ppt, and at 25 ppt only 15% withstood rapid changes and 30% survived step-wise increases. Ventilation frequencies were lowest at 10–15 ppt in step-wise experiments, in conditions that were near isotonic with fish internal plasma concentrations, reflecting lower energy expenditure for osmoregulation. Growth rates appeared greatest at 5–10 ppt, congruent with the larger sizes reached by gobies in Eurasian brackish waters. Thus, we predict that the Great Lakes round goby would thrive in brackish water estuaries along North American coasts, if introduced. However, oceanic salinities appear fatal to the invasive round goby, which likely cannot withstand complete seawater ballast exchanges or oceanic habitats.
Doctor, I Want to Die. Will You Help Me?

IT HAD been 18 months since a 67-year-old retired man whose main joy in life was his two grandchildren was diagnosed with inoperable lung cancer. An arduous course of chemotherapy helped him experience a relatively good year where he was able to remain independent, babysitting regularly for his grandchildren. Recent tests revealed multiple new bony metastases. An additional round of chemotherapy and radiation provided little relief. By summer, pain and fatigue became unrelenting. He was no longer able to tolerate, much less care for, his grandchildren. His wife of 45 years devoted herself to his care and support. Nonetheless, his days felt empty and his nights were dominated by despair about the future. Though he was treated with modern pain control methods, his severe bone pain required daily choices between pain and sedation. Death was becoming less frightening than life itself. See also pp 874 and 875. A particularly severe
Postprocessing method to segregate and quantify the broad components underlying the phosphodiester spectral region of in vivo (31)P brain spectra.

In a typical, in vivo (31)P brain spectrum, the phosphomonoester (PME) and phosphodiester (PDE) spectral region not only contains signals from freely mobile PMEs and PDEs (which are anabolic and catabolic products of membrane phospholipids) but also signals of broader underlying lineshapes from less-mobile molecules. In general, either the PME and PDE resonances are quantified as a combined value of freely mobile metabolites plus less-mobile molecules or the broader underlying signal is reduced/eliminated prior to or post data collection. In this study, a postprocessing method that segregates and quantifies the individual contributions of the freely mobile metabolites and the less-mobile molecules is introduced. To demonstrate the precision and accuracy of the method, simulated data and in vivo (31)P brain spectroscopy data of healthy individuals were quantified. The ability to segregate and quantify these various PME and PDE contributions provides additional spectral information and improves the accuracy of the interpretation of (31)P spectroscopy results. Magn Reson Med 45:390-396, 2001.
Loss and persistence of implicit memory for sound: evidence from auditory stream segregation context effects.

An important question is the extent to which declines in memory over time are due to passive loss or active interference from other stimuli. The purpose of the present study was to determine the extent to which implicit memory effects in the perceptual organization of sound sequences are subject to loss and interference. Toward this aim, we took advantage of two recently discovered context effects in the perceptual judgments of sound patterns, one that depends on stimulus features of previous sounds and one that depends on the previous perceptual organization of these sounds. The experiments measured how listeners’ perceptual organization of a tone sequence (test) was influenced by the frequency separation, or the perceptual organization, of the two preceding sequences (context1 and context2). The results demonstrated clear evidence for loss of context effects over time but little evidence for interference. However, they also revealed that context effects can be surprisingly persistent. The robust effects of loss, followed by persistence, were similar for the two types of context effects. We discuss whether the same auditory memories might contain information about basic stimulus features of sounds (i.e., frequency separation), as well as the perceptual organization of these sounds.
Remote mutations alter transition-state structure of human purine nucleoside phosphorylase

Purine nucleoside phosphorylase (PNP) catalyzes the reversible phosphorolysis of purine (2'-deoxy)ribonucleosides to give the corresponding purine base and (2'-deoxy)ribose 1-phosphate as products. Human and bovine PNPs (HsPNP and BtPNP) form distinct transition states despite 87% identity in amino acid sequence. A PNP hybrid was produced by replacing K22 and H104 in HsPNP with the corresponding Glu and Arg residues found in BtPNP. We solved the transition-state structure of E:R-HsPNP (K22E:H104R mutant of HsPNP) using competitive kinetic isotope effects (KIE) and global density functional calculations. An array of PNP transition states was generated from optimized structure candidates with varied C1'-N9, C1'-Ophosphate distances, ribosyl pucker configurations and N7-protonation states. Isotopically labeled [1'-3H], [2'-3H], [1'-14C], [9-15N], [1'-14C, 9-15N] and [5'-3H2]inosines gave intrinsic KIE values of 1.210, 1.075, 1.035, 1.024, 1.065, 1.063 with E:R-HsPNP, respectively. The suite of E:R-HsPNP KIEs match a single structure from the array of PNP transition-state candidates. The transition state of E:R-HsPNP is fully dissociative, N7-protonated hypoxanthine (C1'-N9 distance >or= 3.0 A) with partial participation of phosphate (C1'-Ophosphate distance = 2.26 A), 2'-C-exo-ribosyl ring pucker and the O5'-C5'-C4'-O4' dihedral angle near 60 degrees . The transition state of E:R-HsPNP is altered from the fully dissociative DN*AN character for HsPNP to a late phosphate-associative character. E:R-HsPNP differs from native HsPNP by only two residues over 25 A away from the active site. New interactions caused by the mutations increase the catalytic efficiency of the enzyme for formation of a late transition state with increased participation of the phosphate nucleophile. Dynamic coupling motions from the remote mutations to the catalytic sites are proposed.
Does prior knowledge facilitate the detection of visual targets in random noise

The detectability of forms embedded within random visual noise has been found to be predictable from the autocorrelation transform of the stimulus pattern (Uttal, 1975). A basic assumption in the autocorrelation theory of form detection is that detectability is determined by the organization of the stimulus pattern, irrespective of the observer’s prior knowledge or expectations about the characteristics of the form. This assumption was tested by determining the effect of the size of the set of alternative target forms on performance of a forced-choice detection task. The targets were composed of dots in a straight line, appearing in one of a specified set of 2, 4, or 8 alternative positions in a pattern of randomly distributed masking dots. Detection accuracy was found to decrease as set size increased, but this decrease was close to what was predicted on the assumption that the random background was independently confusable with the target at each of the alternative positions. Thus, prior knowledge of the set of alternative targets appeared to have no effect on thevisual process, but only on thedecision process by virtue of the features that were relevant criteria for deciding which of the two patterns on each trial was most likely to contain the target. This result is consistent with the autocorrelation theory. This experiment may illustrate how the decision process has influenced the performance in many other experiments that have been assumed to demonstrate an effect of prior knowledge on perception.
Endogenous circadian regulation of pro-inflammatory cytokines and chemokines in the presence of bacterial lipopolysaccharide in humans.

Various aspects of immune response exhibit 24-h variations suggesting that infection susceptibility and treatment efficacy may vary by time of day. Whether these 24-h variations are endogenous or evoked by changes in environmental or behavioral conditions is not known. We assessed the endogenous circadian control and environmental and behavioral influences on ex-vivo lipopolysaccharide stimulation of whole blood in thirteen healthy participants under 48. h of baseline conditions with standard sleep-wake schedules and 40-50. h of constant environmental and behavioral (constant routine; CR) conditions. Significant 24-h rhythms were observed under baseline conditions in Monocyte Chemotactic Protein, Granulocyte-Macrophage Colony-Stimulating Factor and Interleukin 8 but not Tumor Necrosis Factor alpha whereas significant 24-h rhythms were observed in all four immune factors under CR conditions. The rhythm amplitudes, expressed as a percentage of mean, were comparable between immune factors and across conditions. In contrast, the acrophase time (time of the fitted peak) was different between immune factors, and included daytime and nighttime peaks and changes across behavioral conditions. These results suggest that the endogenous circadian system underpins the temporal organization of immune responses in humans with additional effects of external environmental and behavioral cycles. These findings have implications for understanding the adverse effects of recurrent circadian disruption and sleep curtailment on immune function. Â© 2014 Elsevier Inc..
Childhood Obstructive Sleep Apnea: One or Two Distinct Disease Entities?

The increasing prevalence of obesity in children has revealed a clinical picture of obstructive sleep apnea (OSA) that is markedly reminiscent of the typical presentation of OSA in adult patients, and that remarkably differs from the original presentation and manifestations of OSA in non-obese children. Use of this classification may allow for improved delineation of management strategies, and help define potential disparities in short-term and long-term clinical outcomes. This article reviews the pathophysiologic mechanisms of OSA in children, delineates the clinical manifestations associated with the disease, and provides arguments for a novel and potentially useful proposition that defines two types of OSA in children.
Removal of the codeposited carbon layer using He–O glow discharge

Abstract In this study we examine the combination of a He–O glow discharge with heating as a possible technique to remove deuterium from TFTR tiles. Samples were cut from a relatively large area containing a uniform codeposited layer of deuterium and carbon. Auger/SEM was used to generate micrographs of each of the samples. The samples were also examined using Rutherford backscattering to determine the near surface composition. Individual samples were then exposed to a He–O glow discharge while being heated. After the exposure, the samples were returned for Auger/SEM and RBS of the same areas examined prior to the exposure. Comparing the samples before and after exposure revealed that the amount of the codeposited layer removed was significantly less than 1 μm. Removal rates this low would suggest that He–O glow discharge with heating is insufficient to remove the thick layers predicted for ITER in a timely fashion.
Ginzburg-Landau theory of vortices in superfluid 3 He-B

Vortices in superfluid $^{3}\mathrm{He}$ differ qualitatively from all other vortices. In conventional quantized vortices ${(}^{4}$He, superconductors) the order parameter is a scalar function with cylindrical symmetry that vanishes on its axis, but in superfluid $^{3}\mathrm{He}$ the order parameter has nine complex components. More interestingly, the symmetries of the differential equation describing the vortices can be broken by its solutions. In the pressure-temperature phase diagram of $^{3}\mathit{B}$, there is a first-order transition (observed in the shift of the NMR line) between two different vortices that, as recent theory has shown, have different broken symmetries. The vortex observed at high pressures has broken parity with either left- or right-handed vortices. The low-pressure vortex (which is the vortex obtained in the weak-coupling Bardeen-Cooper-Schrieffer theory) has, in addition, broken rotational symmetry around its axis, resulting in a novel double-core structure. The Ginzburg-Landau theory of vortices reproduces the properties of the transition, accounts well for the measured susceptibility and magnetization, and gives detailed predictions about properties not yet measured, such as the jump of the magnetization in the transition, the shift of the transition line in magnetic field, and the orientation of the double-core vortex. The lack of helical instability in the double-core vortex implies that the identification of the vortices is unique. The transition between vortices is interpreted in simple physical terms. A qualitative explanation is given to the metastable state of the low-pressure vortex observed at low temperatures. The numerical method for solving the Ginzburg-Landau equation is discussed.
A Multi-Echelon Inventory Model for a Repairable Item with One-for-One Replenishment

The problem that we address is to determine the inventory stockage levels in a multi-echelon inventory system for a repairable item. In its simplest form the multi-echelon system consists of a set of operating sites supported by a centrally-located repair depot. Each operating site requires a set of working items and maintains an inventory of spare items. The repair depot also holds an inventory of spare items. Item failures are infrequent and are replaced on a one-for-one basis. In this paper we present an exact model for finding the steady-state distribution of the net inventory level at each site. This model assumes that the failures are generated by a compound Poisson process and that the shipment time from the repair depot to each site is deterministic. No assumptions are made with regard to the repair cycle at the depot. We contrast this model with existing models for these systems. Based on the exact model we present an approximation for the steady-state distribution for the case with ample servers at the repair depot. We show that this approximation is very accurate on a set of test problems.
Multiagency Initiative to Provide Greenhouse Gas Information: Global Greenhouse Gas Information System Workshop; Albuquerque, New Mexico, 20–22 May 2009

The second Greenhouse Gas Information System (GHGIS) workshop brought together 74 representatives from 28 organizations including U.S. government agencies, national laboratories, and members of the academic community to address issues related to the understanding, operational monitoring, and tracking of greenhouse gas emissions and carbon offsets. The workshop was held at Sandia National Laboratories and organized by an interagency collaboration among NASA centers, Department of Energy laboratories, and the U.S. National Oceanic and Atmospheric Administration. It was motivated by the perceived need for an integrated interagency, community-wide initiative to provide information about greenhouse gas sources and sinks at policy-relevant temporal and spatial scales. Such an initiative could significantly enhance the ability of national and regional governments, industry, and private citizens to implement and evaluate effective climate change mitigation policies.
Thin Glomerular Basement Membranes

Fig 2. The diagnosis of thin basement membranes is made by electron microscopy. There is diffuse attenuation of the glomerular basement membrane, as illustrated here. In adults, basement membrane thickness less than 250 nm is indicative of thin basement membranes. However, processing and the age of the patient must be taken into consideration, because basement membranes normally increase with maturational growth. Thus, the diagnosis of thin basement membranes in children must be made only after comparison for normal standards in a given laboratory. The presence of thin basement membranes is characteristic of so-called benign familial hematuria, but can also be the only finding in early stages of Alport’s Syndrome, in female carriers of Alport’s Syndrome, and even at stages of established disease in some kindreds with otherwise typical X-linked Alport’s Syndrome. Thus, I prefer to use the term thin basement membrane lesion, rather than disease, because this morphologic finding does not specifically allow definite prognostication. (Transmission electron micrograph, original magnification 33,000).
Unconjugated estriol as an indication for prenatal diagnosis of steroid sulfatase deficiency by in situ hybridization

Abstract Background: Undetectable or very low unconjugated estriol (E3) levels in routine maternal serum screening are associated with steroid sulfatase deficiency, miscarriages, and anencephaly. Cases: Fluorescence in situ hybridization techniques were used in the diagnosis of steroid sulfatase deficiency prenatally in three cases with low or undetectable unconjugated E3 levels. Results showed a male fetus with a deleted steroid sulfatase region, but intact Kallmann syndrome region in all three cases. One mother was studied by fluorescence in situ hybridization and showed a similar deletion for steroid sulfatase gene in one copy of X chromosome (carrier). Conclusion: Women with undetectable or very low levels of estriol on serum screening should be counseled regarding steroid sulfatase deficiency with evaluation by fluorescence in situ hybridization.
The role of ATP in the biogenesis of vaccinia virus mRNA in vitro.

Abstract During in vitro RNA synthesis vaccinia virus rapidly depletes ATP but not GTP, CTP, or UTP. This reduction in ATP concentration results in a decreased rate of RNA synthesis. The RNA transcripts made when ATP becomes rate-limiting are large in size, 20 to 30 S, compared with the 8 to 12 S RNA transcripts synthesized under high ATP concentration. Furthermore, these large RNA transcripts are not significantly polyadenylated and remain virion-associated. When one supplements the RNA polymerase reaction with additional ATP the following observations are made: (a) The rate of RNA synthesis remains constant; (b) the RNA synthesized is of the appropriate monocistronic size, 8 to 12 S; (c) the RNA is polyadenylated efficiently; and (d) the RNA is released from the virus. Some of these effects are mimicked by dATP, but neither the αβ- nor the β,γ-phosphonic acid analogs of ATP will replace ATP in the supplementation scheme. Selection of appropriate ATP concentrations in the in vitro RNA polymerase reaction allows exclusive synthesis of high-molecular-weight RNA.
Minimal string theory

Theorie des cordes minimales. Nous resummons les progres recents dans la comprehension de la theorie minimale des cordes, en se concentrant sur la description des operateurs physiques et des D-branes. Nous passons en revue comment une interpretation geometrique de la theorie minimale des cordes emerge naturellement de l'etude des D-branes. Cette representation geometrique simple associe plusieurs proprietes autrement independantes de la theorie minimale des cordes, et conduit directement a une derivation a partir de la theorie de surface d'univers du modele de matrice dual.
TRIMOLECULAR REACTIONS OF URANIUM HEXAFLUORIDE WITH WATER

The hydrolysis reaction of uranium hexafluoride (UF6) is a key step in the synthesis of uranium dioxide (UO2) powder for nuclear fuels. Mechanisms for the hydrolysis reactions are studied here with...
Economic model predictive control of nonlinear process systems using Lyapunov techniques

In this work, we develop model predictive control (MPC) designs, which are capable of optimizing closed-loop performance with respect to general economic considerations for a broad class of nonlinear process systems. Specifically, in the proposed designs, the economic MPC optimizes a cost function, which is related directly to desired economic considerations and is not necessarily dependent on a steady-state—unlike conventional MPC designs. First, we consider nonlinear systems with synchronous measurement sampling and uncertain variables. The proposed economic MPC is designed via Lyapunovbased techniques and has two different operation modes. The first operation mode corresponds to the period in which the cost function should be optimized (e.g., normal production period); and in this operation mode, the MPC maintains the closed-loop system state within a predefined stability region and optimizes the cost function to its maximum extent. The second operation mode corresponds to operation in which the system is driven by the economic MPC to an appropriate steady-state. In this operation mode, suitable Lyapunov-based constraints are incorporated in the economic MPC design to guarantee that the closed-loop system state is always bounded in the predefined stability region and is ultimately bounded in a small region containing the origin. Subsequently, we extend the results to nonlinear systems subject to asynchronous and delayed measurements and uncertain variables. Under the assumptions that there exist an upper bound on the interval between two consecutive asynchronous measurements and an upper bound on the maximum measurement delay, an economic MPC design which takes explicitly into account asynchronous and delayed measurements and enforces closed-loop stability is proposed. All the proposed economic MPC designs are illustrated through a chemical process example and their performance and robustness are evaluated through simulations. V C 2011 American Institute of Chemical Engineers AIChE J, 58: 855–870, 2012
Time course of oxygen consumption in rats during sudden exposure to high environmental temperature

Abstract Determination of O 2 consumption of three groups of rats (2, 7 to 8 and 16 months old) following sudden exposure to heat (34°C) demonstrated that: a) O 2 consumption increased significantly in the three groups after exposure to 34°C. This increase was sustained for 48 to 72 hr. b) At 48 to 72 hr after exposure, O 2 consumption was returned to normal (28°C values) and continued to decline significantly below the normal values when data were expressed per animal. c) O 2 consumption increased for less than 48 hr in young rats (2 and 7 to 8 months old) and remained elevated for a longer period (72 hr) in the older rats (16 months). This indicated that the young animals acclimate to 34°C temperature earlier than older animals. The findings characterize the metabolic trends in the sequence of the adjustment changes or acclimation of rats exposed to environmental heat. The data presented indicated that temperature and metabolic rate interrelationships depend on time of temperature exposure.
Avatar proxies: configurable informants of collaborative activities

In the physical world, every user exists at one and only one place, but in a collaborative virtual environment (CVE), other paradigms are achievable such as a user existing at more than one place at a time. In a collaborative environment, a user is typically engaged with one primary activity at a time. As the number of collaborative activities increases, users are unable to maintain focal attention on all activities, and must offload some cognitive effort to a peripheral attention sphere. This delegation of attention-the movement of primary activities as focal attention to secondary activities as non-focal attention-requires that users remember certain parameters of context switching, such as what the secondary activities are, and more importantly, when to switch their focal attention to these activities. Keeping track of these context-switching parameters is itself a cognitive load that often degenerates focal attention on primary activities.Our goal is to augment users' cognition by delegating the work of remembering context-switching parameters to other entities in a collaborative environment. We call these entities avatar proxies because our implementation is in a CVE in which users are iconified as avatars, but the techniques and results are general to a broader range of collaborative environments. Avatar proxies notify users when they are required to switch their focal attention to secondary activities.