cssi/SciSciGPT-SciSciNet huggingface dataset:
Identification of anti-inflammatory diterpenes from the marine gorgonian Pseudopterogorgia elisabethae

Analysis of the terpene metabolites of Pseudopterogorgia elisabethae collected from the Florida Keys has resulted in the identification of a novel hydroxyquinone, elisabethadione (1), as well as new pseudopterosins and seco-pseudopterosins. Anti-inflammatory assays indicate that elisabethadione is more potent than the well characterized pseudopterosin A and E. This report also describes the co-occurrence of pseudopterosins and seco-pseudopterosins, diterpenes with amphilectane and serrulatane skeletons, respectively. This together with our previously described isolation of elisabethatriene as the sole diterpene cyclase product in P. elisabethae suggests that the amphilectane and serrulatane families of diterpenes are derived from the same geranylgeranyl diphosphate cyclase product.
Perpetual Learning through Overcoming Inconsistencies

This paper provides a panoramic view on perpetual learning through overcoming inconsistencies. The approach elevates learning stimuli to the first class status and considers inconsistencies as a special type of learning stimuli. As telltales, inconsistencies indicate that an agent is operating at its knowledge boundaries, necessitating subsequent learning episodes. Learning amounts to finding ways to circumvent inconsistencies. We describe a framework called inconsistency induced learning, or i2Learning, and discuss several specific learning algorithms for it. The perpetual nature is embodied in the fact that i2Learning accommodates the open-ended sequence of learning episodes.
Effect of crowding, food deprivation, and diet on flight initiation and lipid reserves of the lesser grain borer, Rhyzopertha dominica

Effects of crowding, food deprivation, and type of cereal diet upon flight initiation, development, body weight, lipid content, and fatty acid composition of the lesser grain borer, Rhyzopertha dominica (F.), were studied in two field strains and one laboratory strain. Beetles of all strains reared under crowded conditions had significantly higher flight initiation than beetles reared on isolated kernels (uncrowded). Regardless of degree of crowding, flight initiation increased with the period of food deprivation up to a maximum at 24 h, after which flight initiation declined. Body weight and lipid content decreased as the food deprivation period increased, whereas fatty acid composition was not significantly affected by food deprivation. Beetles from a field strain collected in 1995 had higher flight initiation and increased lipid content compared with beetles from the laboratory strain. However, beetles from the laboratory strain were larger, developed faster, and were more fecund than beetles from this field strain. The cereal diet on which beetles were reared also had a significant effect on flight initiation, lipid content, and fatty acid composition. Beetles reared on whole rice and wheat produced adults with higher flight initiation, higher lipid content, and higher oleic acid concentration than beetles reared on whole corn and sorghum.
Error and stability estimates for surface-divergence free RBF interpolants on the sphere

Recently, a new class of surface-divergence free radial basis function interpolants has been developed for surfaces in ℝ 3 . In this paper, several approximation results for this class of interpolants will be derived in the case of the sphere, S 2 . In particular, Sobolev-type error estimates are obtained, as well as optimal stability estimates for the associated interpolation matrices. In addition, a Bernstein estimate and an inverse theorem are also derived. Numerical validation of the theoretical results is also given.
Analysis of time-resolved scattering from macroscale bacterial colonies

We investigate the relationship of incubation time and forward-scattering signature for bacterial colonies grown on solid nutrient surfaces. The aim of this research is to understand the colony growth characteristics and the corresponding evolution of the scattering patterns for a variety of pathogenic bacteria relevant to food safety. In particular, we characterized time-varying macroscopic and microscopic morphological properties of the growing colonies and modeled their optical properties in terms of two-dimensional (2-D) amplitude and phase modulation distributions. These distributions, in turn, serve as input to scalar diffraction theory, which is, in turn, used to predict forward-scattering signatures. For the present work, three different species of Listeria were considered: Listeria innocua, Listeria ivanovii, and Listeria monocytogenes. The baseline experiments involved the growth of cultures on brain heart infusion (BHI) agar and the capture of scatter images every 6 h over a total incubation period of 42 h. The micro- and macroscopic morphologies of the colonies were studied by phase contrast microscopy. Growth curves, represented by colony diameter as a function of time, were compared with the measured time-evolution of the scattering signatures.
Modeling Agent Auctions in a Supply Chain Environment

Agent-based auction technology has revolutionized auction trading in the Supply Chain environment by reducing the cost of transactions, and by increasing the satisfaction factor in matching requirements of seller and buyer agents. In this article, we have considered methods of matching quantities of buyer and seller agents by cooperation, with a priority on the buyerâ€™s requirements. The article discusses the architecture of the agent and the agent community when there is cooperative matching of volume. We present a Dynamic Programming algorithm to describe the agentâ€™s decision process, and heuristic algorithms as the practical solution methodology. The results of a simple experiment show the improvement achieved by cooperation.
Semipreparative Separation of Intact Hopanoids from Zymomonas Mobilis

Hopanoids are an important class of molecules that play a structural and physiological role in the membrane processes of prokaryotic and plant cells. Studies on the function of hopanoids require milligram quantities but have been limited by current procedures for isolation and characterization: most separations have isolated only derivatized compounds of hopane in microgram quantities. Our method employs aminopropyl bonded-phase solid-phase extraction columns with sequential elution and silica semipreparative HPLC with isocratic elution. When applied to freeze-dried cells of Zymomonas mobilis, the procedure separated the three major hopanoids present (bacteriohopanetetrol, bacteriohopanetetrol-glucosamine, and bacteriohopanetetrol-ether) from the other lipid classes. Using the solid-phase extraction column, a fraction containing an average of 3.3 mg of bacteriohopanetetrol per gram dry weight of cells was recovered without any detectable impurities along with a fraction that contained a mixture of the other two hopanoids. After this mixture was subsequently purified by semipreparative HPLC, approximately 4.7 mg of bacteriohopanetetrol-glucosamine and 3.6 mg of bacteriohopanetetrol-ether per gram dry weight of cells could be separated and recovered.
Neuroimaging differences between older adults with maintained versus declining cognition over a 10-year period

Abstract Background Maintaining cognitive function protects older adults from developing functional decline. This study aims to identify the neuroimaging correlates of maintenance of higher global cognition as measured by the Modified Mini Mental State Test (3MS) score. Methods Repeated 3MS measures from 1997–98 through 2006–07 and magnetic resonance imaging with diffusion tensor in 2006–07 were obtained in a biracial cohort of 258 adults free from dementia (mean age 82.9 years, 56% women, 42% blacks). Participants were classified as having shown either maintenance (3MS slope > 0) or decline (3MS slope Results Differences between cognitive maintainers (n = 153) and non-maintainers (n = 107) were significant for GMv of the medial temporal area (35.8%, p = 0.004) and lower MD of the cingulate cortex (37.9%, p = 0.008), but not for other neuroimaging markers. In multivariable regression models adjusted for age, race, WMHv and GMV from the total brain and vascular conditions, each standard deviation of GMv of the medial temporal area and each standard deviation of MD of the cingulate cortex were associated with a nearly 4 times greater probability (odds ratio [standard deviation]: 3.80 [1.16, 12.44]) and a 34% lower probability (0.66, [0.46, 0.97]) of maintaining cognitive function, respectively. In these models neither WMHv nor GMv from total brain were significantly associated with probability of maintaining cognitive function. Conclusions Preserving the volume of the medial temporal area and the microstructure of the cingulate cortex may contribute to maintaining cognitive function late in life.
Regulation of an Inwardly Rectifying ATP-sensitive K+ Channel in the Basolateral Membrane of Renal Proximal Tubule

The potassium conductance of the basolateral membrane (BLM) of proximal tubule cells is a critical regulator of transport since it is the major determinant of the negative cell membrane potential and is necessary for pump-leak coupling to the Na+,K+-ATPase pump. Despite this pivotal physiological role, the properties of this conductance have been incompletely characterized, in part due to difficulty gaining access to the BLM. We have investigated the properties of this BLM K+ conductance in dissociated, polarized Ambystoma proximal tubule cells. Nearly all seals made on Ambystoma cells contained inward rectifier K+ channels (γslope, in = 24.5 ± 0.6 pS, γchord, out = 3.7 ± 0.4 pS). The rectification is mediated in part by internal Mg2+. The open probability of the channel increases modestly with hyperpolarization. The inward conducting properties are described by a saturating binding–unbinding model. The channel conducts Tl+ and K+, but there is no significant conductance for Na+, Rb+, Cs+, Li+, NH4+, or Cl−. The channel is inhibited by barium and the sulfonylurea agent glibenclamide, but not by tetraethylammonium. Channel rundown typically occurs in the absence of ATP, but cytosolic addition of 0.2 mM ATP (or any hydrolyzable nucleoside triphosphate) sustains channel activity indefinitely. Phosphorylation processes alone fail to sustain channel activity. Higher doses of ATP (or other nucleoside triphosphates) reversibly inhibit the channel. The K+ channel opener diazoxide opens the channel in the presence of 0.2 mM ATP, but does not alleviate the inhibition of millimolar doses of ATP. We conclude that this K+ channel is the major ATP-sensitive basolateral K+ conductance in the proximal tubule.
Absence of brain-derived neurotrophic factor and trkB receptor immunoreactivity in glia of Alzheimer's disease

Alterations in the neuronal expression of some neurotrophins have been shown in various neurodegenerative processes, particularly Alzheimer's disease (AD). Glia may up-regulate neurotrophins and their high-affinity tyrosine kinase (trk) receptors in response to neural injury. In human immunodeficiency virus type 1 (HIV-1) encephalitis, activated microglia were shown to express brain-derived neurotrophic factor (BDNF), while reactive astrocytes expressed trkB receptor. This observation has suggested the existence of local neurotrophic regulation between different glial populations. To characterize the glial cellular distribution of BDNF and trkB receptor proteins in AD, we studied selected regions of postmortem brains from four AD and three age-matched control patients by double-immunofluorescence confocal microscopy. In both groups, BDNF immunoreactivity was distributed in neuronal perikarya and neuritic processes in the neocortex and hippocampus. No BDNF immunoreactivity was observed in microglia or astrocytes within and between senile plaques of AD. Catalytic trkB receptor immunoreactivity was present in neuronal perikarya in the neocortex and hippocampus. Reactive astrocytes and microglia were not immunoreactive for catalytic trkB. The absence of BDNF and trkB proteins in glia in AD patients is in contrast to the finding in patients with HIV-1 encephalitis. This difference suggests that glial expression of BDNF and trkB proteins may be characteristic of particular disease processes, rather than merely representing a stereotyped response to any type of neural injury.
Erosion of stereochemical control with increasing nucleophilicity: O-glycosylation at the diffusion limit.

Nucleophilic substitution reactions of 2-deoxyglycosyl donors indicated that the reactivity of the oxygen nucleophile has a significant impact on stereoselectivity. Employing ethanol as the nucleophile resulted in a 1:1 (α:β) ratio of diastereomers under SN1-like reaction conditions. Stereoselective formation of the 2-deoxy-α-O-glycoside was only observed when weaker nucleophiles, such as trifluoroethanol, were employed. The lack of stereoselectivity observed in reactions of common oxygen nucleophiles can be attributed to reaction rates of the stereochemistry-determining step that approach the diffusion limit. In this scenario, both faces of the prochiral oxocarbenium ion are subject to nucleophilic addition to afford a statistical mixture of diastereomeric products. Control experiments confirmed that all nucleophilic substitution reactions were performed under kinetic control.
Peak-to-Average Power Ratio Characteristics of WCDMA over Satellite Communication Links

It is well known that WCDMA signals exhibit a higher peak to average power ratio (PAPR) than TDMA signals. When WCDMA is implemented in a satellite link, the relatively high PAPR presents a number of problems related to power levels on the spacecraft. First, in order to maintain linearity it may be necessary to operate the satellite amplifiers at backoffs greater than those used for TDMA systems. Second, the high peak power levels can affect the survivability of the satellite - instantaneously high peak power levels can damage spacecraft electronic components. The purpose of this paper is to determine the PAPR characteristics of WCDMA over satellite. We evaluate the PAPR statistics of the satellite downlink signal as a function of satellite loading, traffic characteristics, and other relevant parameters. We show that the PAPR can be significantly reduced by introducing relative time delays between each WCDMA carrier. The results of the paper are directly applicable to the MUOS system currently being developed by DoD.
RNA polymerase II C-terminal domain: Tethering transcription to transcript and template

The RNA polymerase II (Pol II) C-terminal domain (CTD) is a repetitive disordered domain that extends from the catalytic core of the enzyme. This “tail” domain is heavily modified by phosphorylation, glycosylation and proline isomerization. In addition to the enzymes that modify the tail a number of RNA processing factors and chromatin modification factors interact with the CTD. Thus, this domain acts as a tether to bring into close proximity the machinery necessary to synthesize and process Pol II transcripts. By definition the CTD consists of the amino acid sequences extending from the largest subunit, RPO21 or RPB1 in yeast and POLR2A in human. Specifically the CTD consists of sequences beyond the most C-terminal region that is conserved among the largest subunits of all multi-subunit RNA polymerases 1. This “H” homology region plays a role in positioning the catalytic core and provides surfaces for interactions with Rpb2 and Rpb6 2. The CTD thus consists of three regions (Figure 1). In order of proximity to the catalytic core these are the linker, the heptad repeats, and a C-terminal non-repeat or “tip” domain. The linker region is not conserved among different organisms but does contain an enrichment of amino acids found in the CTD. Open in a separate window Figure 1 Diagram showing the three regions of the CTD.
Correction of Murine Hemophilia A and Immunological Differences of Factor VIII Variants Delivered by Helper-dependent Adenoviral Vectors

Bioengineering of the factor VIII (FVIII) molecule has led to the production of variants that overcome poor secretion and/or rapid inactivation. We tested six modified FVIII variants for in vivo efficacy by expressing them from helper-dependent adenoviral (HD-Ad) vectors. We constructed a wild-type (WT) variant, a B-domain-deleted (BDD) variant, a point mutant for improved secretion (F309S), a variant with a partial B-domain deletion for improved secretion (N6), a combination of the point mutant and partial BDD variant (F309N6), and an inactivation-resistant (IR8) FVIII variant. All the constructs expressed functional protein after injection of high-dose HD-Ad. Activity ranged from 20 to 50% with WT, to ∼100% with the N6 and F309N6 variants. Interestingly, mice treated with N6 showed long-term FVIII activity and phenotypic correction for up to 74 weeks, with low anti-FVIII antibody titer. Importantly, the N6 variant was therapeutically efficacious even after a 50% reduction of viral dose, thereby indicating that transgene modification itself can improve the dose efficacy of HD-Ad. This finding is significant, because dose efficacy is a key factor in clinical application. In summary, bioengineering of the FVIII molecule may be an effective approach to improving the safety, immunogenicity, and efficacy of HD-Ad gene therapy in hemophilia A (HA).
Sunflower water productivity in four Great Plains soils

Abstract Sunflower (Helianthus annuus L.) is a drought-adapted crop whose short growing season reduces irrigation requirements which makes it ideal for regions with limited irrigation water supplies. Our objectives were to (a) evaluate the yield (Y) potential of sunflower under full and deficit irrigation (IR), (b) determine if water productivity (WP) and irrigation water productivity (IWP) of sunflower were affected by soil textural class differences and (c) compare the WP relationship to a benchmark maximum productivity relationship for consideration of limitations to crop yield in a semiarid environment. Sunflower was grown in 2008 and 2009 in 48 weighing lysimeters under an automated rain shelter containing soil monoliths of four regional soils – clay loam, silt loam, sandy loam or fine sand (12 each) – at Bushland, TX, USA, a semiarid region of the southern Great Plains. Irrigation treatments were 25%, 50%, 75% and 100% replacement of evapotranspiration. The regression of IR:Y for all soil textural classes showed that irrigation increased yield by 0.47 g m−2 mm−1 in 2008 and 0.51 g m−2 mm−1 in 2009. Averaged across irrigation treatments, the WP of the crops in the fine sand (0.54 kg m−3) was larger than that of the crops in the silt loam (0.46 kg m−3) and clay loam (0.44 kg m−3). The IWP of the crops in the fine sand (1.0 kg m−3) and the sandy loam (0.96 kg m−3) were significantly larger than the IWP of the crops in the clay loam (0.72 kg m−3). Yields were as much as 30% lower at full irrigation levels compared with benchmark maximum yields. Probable limitations to increased yield include high evaporative deficits and soil water evaporation. Although sunflower may be a drought-adapted crop, maximum yields may be difficult to achieve due to the climatic conditions in the southern Great Plains.
Effect of Pre‐irradiation Heating Temperatures, Irradiation Level, and Storage Time at 34° F on the Free Amino Acid Composition of Beefa,b

SUMMARY Slices of fresh beef were heated to 130, 150, and 1.95°F, then irradiated at 0.1 and 5.0 megarads, and stored at 34°F for periods up to 60 days. Unheated and unirradiated beef was subjected to the same variables. No free lysine, lysine, or tryptophan was found. Heating to 150°F inhibited the release of amino acids from the parent protein. Histidine and tyrosine were observed in quantitative amounts, but only traces of alanine, glycine, leueine, threonine, and valine were observed at 60 days. Heating to 150°F completely inhibited the appearance of aspartic acid, glutamic acid, serine, methionine, and phenylalanine. Methionine and valine were affected by radiation at both levels. Serine, phenylalanine, histidine, glycine, glutamic acid, aspartic acid, and alanine were affected only at the 5.0-megarad level. Storage generally resulted in increasing quantities of the free amino acids except for arginine and proline.
Intercalators as probes of DNA conformation: Propidium binding to alternating and non-alternating polymers containing guanine

Summary Propidium iodide is used as a structural probe for alternating and nonalternating DNA polymers containing guanine and the results are compared to experiments with poly[d(A-T)2], poly(dA · dT) and random DNA sequences. Viscometric titrations indicate that propidium binds to all polymers and to DNA by intercalation. The binding constant and binding site size are quite similar for all alternating polymers, non-alternating polymers containing guanine and natural DNA. Poly(dA · dT) is unusual with a lower binding constant and positive cooperativity in its propidium binding isotherms. Poly(dA · dT) and poly(dG · dC) have similar salt effects but quite different temperature effects in propidium binding equilibria. Polymers and natural DNA have similar rate constants in their SDS driven dissociation reactions. The association rate constants are similar for the alternating polymers and poly(dG · dC) but are significantly reduced for poly(dA · dT). These results suggest that natural DNA, the alternating polymers, and nonalternating polymers containing guanine convert to an intercalated conformation with bound propidium in a very similar manner.
Managing data entry of a large-scale interview project with optical scanning hardware and software

A hardware and software system for the cost-effective preparation of interview data is described. Scantron optical scanning hardware and DataBlocks software were used to prepare ASCII data files from structured interviews and questionnaires. These data were then edited for analysis with SPSS-X Data Entry software. Three different processes for preparing interview data were compared. Time, personnel, hardware, and software costs were projected for each process, as well as comparative risks to the integrity of data. A scanning procedure saves time and money, and it reduces the risk of errors.
L’entose, mort cellulaire par cannibalisme entre cellules tumorales

> La mort cellulaire joue un role cle dans le developpement de nombreux organes et dans l’homeostasie tissulaire chez l’adulte. Un dereglement de l’equilibre entre la proliferation et la mort cellulaires peut conduire au developpement de maladies degeneratives par un exces de mort cellulaire, ou a l’emergence de cancers en cas de deficit. Les cellules peuvent declencher leur autodestruction en reponse a un stress intracellulaire ou un signal de mort extracellulaire. Ce processus de mort cellulaire physiologique appele apoptose (ou suicide cellulaire) est genetiquement controle et fut particulierement etudie ces dernieres annees [1]. Par exemple, le detachement de cellules epitheliales de la matrice extracellulaire sous-jacente declenche leur elimination par une forme d’apoptose appelee anoikis [2] (du grec « sans-abri »). L’anoikis est ainsi induite par la perte de l’engagement des integrines membranaires qui ancrent les cellules aux proteines de la matrice extracellulaire. Les integrines sont habituellement connectees aux microfilaments d’actine par leur domaine intracellulaire. Les cellules cancereuses sont generalement resistantes a la mort induite par anoikis. Cette resistance leur confererait potentiellement la capacite de survivre au voyage en dehors de la tumeur primaire et de former ainsi des metastases. D’autres processus de mort non-apoptotique, comme la necrose cellulaire ou l’autophagie par exemple [3], peuvent parfois agir en synergie avec l’apoptose pour occire efficacement une cellule et peuvent aussi compenser une apoptose deficiente [4, 5]. Mise en evidence et caracteristiques de l’entose Recemment, un autre processus de mort cellulaire alternatif a ete mis en evidence lorsque des cellules epitheliales perdent contact avec leur substrat in vitro [6]. Ainsi, des cellules de lignees epitheliales d’origine mammaire peuvent aussi former en suspension des agregats ou des cellules se retrouvent completement encapsulees dans des vacuoles au sein de cellules voisines (Figure 1). Ce processus nomme « entose », du grec entos (« dedans ») se deroulait en parallele de l’anoikis dans ce modele in vitro [6]. A premiere vue, la concomitance de ces deux processus pourrait suggerer que ce phenomene d’internalisation correspond a la phagocytose de cellules mortes en anoikis par leurs voisines encore en vie. Au cours de l’apoptose, la cellule mourante emet des signaux. En particulier, elle expose sur le feuillet externe de la membrane plasmique des residus phosphatidylserine (PS), un phospholipide normalement situe sur son feuillet interne, qui permettront sa reconnaissance, sa phagocytose et son elimination par les macrophages et d’autres
Use of dominant eigenvalues in evaluating the probability density function of the intensity for a polychromatic speckle pattern

A method has been described to determine a priori the optimum number of samples required to estimate the eigenvalues in the Karhunen–Loeve expansion of a polychromatic speckle pattern without solving the relevant integral equation. It is found that choosing samples less than this number leads to an incorrect estimate of the eigenvalues, while choosing a larger number of samples does not change the eigenvalues significantly. Thus the method allows the use of the Karhunen–Loeve expansion with minimum effort and leads to an accurate estimate of the probability density function of the intensity. Owing to the general nature of this method, it is also applicable to a large class of problems where the Karhunen–Loeve expansion is used.
111Indium Pentetreotide Imaging in the Evaluation of Head and Neck Tumors

Objectives/Hypothesis: Peptide receptor imaging with 111Indium pentetreotide is useful in the diagnosis of diffuse neuroendocrine system tumors (DNEST) of the head and neck. Uses of 111Indium pentetreotide scintigraphy include tumor and metastases detection, familial tumor screening, and surveillance for recurrence. Using target to background ratios (TBR) could generate a comparative scale for these tumors. Study Design: A retrospective study evaluated the size, TBR, conventional imaging, and outcomes of patients imaged with 111Indium pentetreotide scintigraphy for suspected head and neck DNEST. Methods: Patients with head and neck tumors imaged by 111Indium pentetreotide scintigraphy during a nine-year period were reviewed. Data analyzed were age, sex, scintigraphy, pathology, and conventional radiology. Tumor data included dimension, multiplicity, metastases, and tumor and brain counts. Results: Fifty-three patients underwent 58 scans. The sensitivity and specificity were 93% and 92%. Several different DNEST were successfully evaluated, including familial paragangliomas and multiple paragangliomas. TBRs were variable depending on type of DNEST. Conclusions:111Indium pentetreotide scintigraphy is accurate in determining the presence of paragangliomas, carcinoid tumors, esthesioneuroblastomas, small cell neuroendocrine tumors, andmetastases. It is an excellent surveillance tool. Screening patients for familial paragangliomas can be accomplished. No reliable comparative scale to distinguish amongst the various DNEST could be developed using TBR.
Vitamins C and K3 sensitize human urothelial tumors to gemcitabine.

Purpose: We evaluated the antitumor effects of vitamins C and K3 for human urothelial carcinoma and the potential use of the combination of vitamins C plus K3 as a sensitizing agent for conventional chemotherapy for urothelial carcinoma.Materials and Methods: The antiproliferative and apoptotic effects of vitamin C alone, vitamin K3 alone, vitamins C plus K3, gemcitabine alone and gemcitabine plus vitamins C plus K3 were assessed in vitro by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, propidium iodide staining and flow cytometry. For in vivo studies we implanted UMUC-14 tumorigenic urothelial carcinoma cells into the subcutis of nude mice. One week later we treated 10 mice each with saline (control), vitamins C plus K3, gemcitabine or gemcitabine plus vitamins C plus K3. Treatment was continued for 4 weeks, followed by necropsy. Tumor volume was measured and tumor kinetics were established. Apoptosis and proliferation were evaluated in tumor sections using immunohistochemistr...
Modeling Variants of Alzheimer's Ion Channels in the Lipid Bilayer formed by an Aggregation-Intermediate β-Hairpin and E22Δ Mutant

We modeled Alzheimer's Aβ1-42 ion channel in a β-barrel structure embedded in the lipid bilayer using explicit molecular dynamics (MD) simulations. Our Aβ barrels consist of multimeric chains of Aβ1-42 peptide. Wild-type Aβ1-42 β-hairpins with a turn at 26Ser-27Asn were used to construct the single-layered β-sheet barrels with different sizes (4-, 6-, 8-, and 10-mer). We considered two potential β-sheet motifs: turn-next-to-turn β-hairpins in NCNC packing mode and turn-next-to-tail β-hairpins in NCCN packing mode, where N and C denote the N- and C-terminal strands, respectively. In the NCNC β-hairpins packing, the disordered N-termini are located at the one side of the bilayer, while in the NCCN β-hairpins packing they are located at both bilayer sides. In our simulations, the smaller β-hairpin barrels (4- and 6-mer), whether they started from β-hairpin bundle or preassembled β-barrel structures, are too narrow to conduct ions and therefore do not preserve the solvated pores. In contrast, the larger β-hairpin barrels (8- and 10-mer) present the solvated pores, wide enough for conducting ions and water. The structures of large barrels are very similar to naturally occurring β-barrels in membrane, suggesting possible variants of Aβ channels with the single-layered β-sheet motif. We also observed that the Osaka mutant (Aβ1-42 E22Δ, a deletion of 22Glu) barrels formed by the U-shaped peptides can only be stabilized by the inner β-sheet after breaking the outer β-sheet due to the loss of hydrophobic pocket between the sheets. This suggests that toxic amyloid ion channels are polymorphic in the common β-barrel motif. Funded by Frederick National Laboratory for Cancer Research, National Institutes of Health, under contract HHSN261200800001E.
Regulation of mitochondrial apoptotic events by p53-mediated disruption of complexes between antiapoptotic bcl-2 members and bim

Multiple mechanisms have been proposed for the mitochondrial function of p53 that are either dependent on or independent of its transcriptional activity. However, none of these mechanisms involves Bim functioning downstream of p53 mitochondrial translocation. Utilizing a p53 nuclear localization signal mutant, whose nuclear import is completely abrogated, we demonstrate that its apoptotic activity at the outer mitochondrial membrane, which involves conformational changes in Bax and Bak, is mediated by Bim. We further demonstrate an inverse correlation between the binding levels of p53 and Bim to Mcl-1. Thus, enhanced binding of p53 to Mcl-1 involves the disruption of existing complexes between Mcl-1 and Bim. We propose that mitochondrial p53 functions as a Bim derepressor by releasing Bim from sequestrating complexes with Mcl-1, Bcl-2, and Bcl-XL, and allowing its engagement in Bak/Bax activation.
Nanosized carbon-rich grains in carbonaceous chondrite meteorites

Abstract Macromolecular carbonaceous material is common in primitive meteorites. Little information exists on its form and composition, and there are no published data on nanometer-scale chemical and structural variations. Transmission electron microscopy (TEM) studies of CM meteorites reveal abundant, previously unrecognized nanosized carbonaceous grains. They have a high aromatic component as revealed by electron energy-loss spectroscopy (EELS), with up to 20 at.% substituted by S, N, and O. They occur as discrete hollow and solid nanospheres and sparse nanotubes. The grains exhibit considerable variations in composition, size, morphology, and abundance among meteorites and may represent materials from multiple reservoirs.
The time-course of rod-cone interaction.

Abstract The time-course of rod-cone interaction (change of scotopic sensitivity caused by photopic background stimulation) was measured in the presence of briskly exchanged, scotopically matched, 490- and 630-nm background disks. In all conditions, interaction rose and feel quickly with changes of photopic stimulation. When the background was a small 0.6°-diameter disk, photopic stimulation produced relatively constant maintained interaction of about 0.6 log units. When the background was a large 7.8°:-dia disk, photopic stimulation produced larger initial (0.6–1.0 log unit) than maintained (0.2 log unit) interaction. When a 0.6° by 7.8° annulus was used instead of a background, photopic stimulation produced substantial interaction only at offset, a transitory interaction. Thus, the spatial dependence of transitory interactions differs from that of maintained interaction: transitory interactions can be large even when maintained interaction is small or absent. The results are discussed in terms of a simple center-surround model of rod-cone interaction that unifies both maintained and transient interaction.
Soot formation and oxidation in laminar diffusion flames

A numerical model of soot formation and oxidation has been examined in terms of the integrated soot volume fraction across a series of laminar diffusion flames. Agreement with experiments was found to be good. A comparison of the conversion rate of carbon to soot in the flames was also satisfactory. OH was shown to be the dominant oxidizer of soot low in the co-flow axisymmetric flames but as the flame tip was approached the calculations suggested that O 2 became more important. Both species were important to the correct prediction of soot profiles. The rate of OH loss on soot was found to be comparable to the net rates of OH loss and formation by flame chemistry. These results indicate that soot may be a significant sink of OH and may, in fact, lead to local extinction of the reaction zone near the flame tip.
Approaches To Quantitative Analysis With Infrared Spectroscopy

Two trends can be discerned in the recent development of methods for quantitative analysis using infrared spectroscopy. The first is the adoption of methods which use whole regions or complete spectra rather than a limited number of discrete frequencies. This can be attributed to the availability of the necessary computing power at low cost. Fourier transform spectrometers provide a complete spectrum with no time penalty relative to a measurement at a single frequency. This too has encouraged the development of these methods. The second trend has been the move away from reliance on Beer's Law. Statistical approaches, well established in other fields, can perform well in situations where there is no linear, or other simple relationship between absorbance and the value of the property of interest. These methods have encouraged the application of IR spectroscopy to the quantitative analysis of increasingly complex mixtures, and to the determination of properties other than component concentrations. This paper will deal with the move away from methods based explicitly on Beer's Law. This change is probably more significant than the extension of traditional approaches from discrete frequency to complete spectra. The mathematics will not be treated in any detail. It is possible to identify the advantages and limitations of the various approaches by examining the underlying ideas rather than the detail of the algorithms.
DISTRIBUTION OF ZINC-65 IN THE WASP, HABROBRACON, AND ITS EFFECTS ON REPRODUCTION

Adults of the habrobracon wasp were fed with Zn/sup 65/ sulfate or exposed externally to Zn/sup 65/ chloride. The radioactivity of whole wasps, body parts, and eggs were measured along with the hatchability of the eggs. Eggs were most radioactive on the third day and egg production was consistently lower than for control wasps. Nearly all the radioactivity in the wasp was abdominal; during the first two days, most of the ingested Zn/sup 65/ was associated with the digestive tract. In the male, the reproductive system did not become appreciably radioactive. Since less than 20% of the Zn/sup 65/ meal is eliminated via the eggs, it is concluded that the effects of Zn/sup 65/ are due to zinc toxicity. (D.L.C.)
Public perceptions of state police: An analysis of individual-level and contextual variables

Abstract Research focusing on citizens' perceptions of police has been widespread at the local level; however, little attention has been devoted to state policing organizations. This focus is particularly interesting considering the enhanced role state police agencies have assumed in recent years. This study analyzes categorical and ordered categorical attitudinal data collected from a statewide sample in the State of Washington. Among the findings reported are significant gender differences and the observation that the number of citations an individual has received affects his or her perceptions of state police.
Methanolysis of seed oils in flowing supercritical carbon dioxide

The direct methanolysis of triglycerides in flowing supercritical carbon dioxide by an immobilized lipase is described. The reaction system consists of two syringe pumps for substrate addition and another two syringe pumps for delivering CO2 at 24.1 MPa. Corn oil is pumped into the carbon dioxide stream at a rate of 4 μL/min, and methanol is pumped at 5 μL/min to yield fatty acid methyl esters (FAME) at >98% conversion. Direct methanolysis of soy flakes gives FAME at similar yields. This combined extraction/reaction is performed at 17.2 MPa and 50°C. The fatty acid profiles obtained for these seed oils matches those obtained by classical chemical synthesis.
Sensitivity analysis and evaluation of microFacCO: a microscale motor vehicle emission factor model for CO emissions.

ABSTRACT This paper presents a sensitivity analysis of a microscale emission factor model (MicroFacCO) for predicting realtime site-specific motor vehicle CO emissions to input variables, as well as a limited field study evaluation of the model. The sensitivity analysis has shown that MicroFacCO emission estimates are very sensitive to vehicle fleet composition, speed, and ambient temperature. For the present U.S. traffic fleet, the CO emission rate (g/mi) is increased by more than 500% at 5 mph in comparison with a speed greater than 40 mph and by ~67% at ambient temperatures of 45 °F and ≥95 °F in comparison with an ambient temperature of 75 °F.
On the Hybrid Propositional Encodings of Planning

Recently, casting planning as propositional satisfiability (SAT) has been shown to be an efficient technique of plan synthesis. This article is a response to the recently proposed challenge of developing novel propositional encodings that are based on a combination of different types of plan refinements and characterizing the tradeoffs. We refer to these encodings as hybrid encodings. An investigation of these encodings is important, because this can give insights into what kinds of planning problems can be solved faster with hybrid encodings. Encodings based on partial–order planning and state–space planning have been reported in previous research. We propose a new type of encoding called a unifying encoding that subsumes these two encodings. We also report on several other hybrid encodings. Next, we show how the satisfiability framework can be extended to incremental planning. State–space encoding is attractive because of its lower size and causal encoding is attractive because of its highest flexibility in reordering steps. We show that hybrid encodings have a higher size and a lower flexibility in step reordering and, thus, do not combine the best of these encodings. We discuss in detail several specific planning scenarios where hybrid encodings are likely to be superior to nonhybrid encodings.
Prediction-based picture prioritisation method for hierarchical B-structure of high efficiency video coding

The current high efficiency video coding standard does not provide any syntax for prioritising pictures in the same temporal level of hierarchical structure. Thus, this reported work reveals how the current uniform prioritisation method in hierarchical B pictures can cause severe video quality degradation when video packets are transmitted over error-prone channels. To solve this problem, a new picture prioritisation method using prediction information is proposed.
Effect of Substrate Henry’s Constant on Biofilter Performance

Abstract Butanol, ether, toluene, and hexane, which have Henry's constants ranging from 0.0005 to 53, were used to investigate the effects of substrate solubility or availability on the removal of volatile organic compounds (VOCs) in trickle-bed biofilters. Results from this study suggest that, although removal of a VOC generally increases with a decrease in its Henry's constant, an optimal Henry's constant range for biofiltration may exist. For the treatment of VOCs with high Henry's constant values, such as hexane and toluene, the transfer of VOCs between the vapor and liquid phases or between the vapor phase and the biofilm is a rate-determining step. However, oxygen (O2) transfer may become a rate-limiting step in treating VOCs with low Henry's constants, such as butanol, especially at high organic loadings. The results demonstrated that in a gas-phase aerobic biofilter, nitrate can serve both as a growth-controlling nutrient and as an electron acceptor in a biofilm for the respiration of VOCs with lo...
Colocalization of Barley Lectin and Sporamin in Vacuoles of Transgenic Tobacco Plants

Various targeting motifs have been identified for plant proteins delivered to the vacuole. For barley (Hordeum vulgare) lectin, a typical Gramineae lectin and defense-related protein, the vacuolar information is contained in a carboxyl-terminal propeptide. In contrast, the vacuolar targeting information of sporamin, a storage protein from the tuberous roots of the sweet potato (Ipomoea batatas), is encoded in an amino-terminal propeptide. Both proteins were expressed simultaneously in transgenic tobacco plants to enable analysis of their posttranslational processing and subcellular localization by pulse-chase labeling and electron-microscopic immunocytochemical methods. The pulse-chase experiments demonstrated that processing and delivery to the vacuole are not impaired by the simultaneous expression of barley lectin and sporamin Both proteins were targeted quantitatively to the vacuole, indicating that the carboxyl-terminal and amino-terminal propeptides are equally recognized by the vacuolar protein-sorting machinery. Double-labeling experiments showed that barley lectin and sporamin accumulate in the same vacuole of transgenic tobacco (Nicotiana tabacum) leaf and root cells.
Molecular epidemiology of group A streptococcus causing scarlet fever in northern Taiwan, 2001–2002

In this study, 830 Streptococcus pyogenes isolates collected between 2001 and 2002 from patients with scarlet fever in northern Taiwan were analyzed by M protein gene (emm) sequence typing, pulsed-field gel electrophoresis (PFGE), and antimicrobial susceptibility testing. A total of 21 emm types and 56 PFGE patterns were identified. The most frequent emm types were emm1 (29.2%), emm4 (24.1%), emm12 (19.0%), emm6 (15.8%), stIL103 (5.7%), and emm22 (1.9%). Antimicrobial resistance profiles were determined, and resistance to erythromycin (24.6%), clindamycin (2.0%), and chloramphenicol (1.3%) was detected. Five major emm types (emm4, emm12, emm1, emm22, and emm6) accounted for 95.6% of the erythromycin-resistant isolates. The decreased prevalence of erythromycin-resistant emm12 strains coincided with the overall decrease in erythromycin resistance from 32.1% in 2001 to 21.1% in 2002 in Taiwan. Five major clones (emm4/2000, emm12/0000, emm4/2010, emm1/1000, and emm22/8100) represented 72.1% of the erythromycin-resistant isolates. The survey of group A Streptococcus emm types, genetic diversity, and antibiotic resistance has direct relevance to current antimicrobial use policies and potential vaccine development strategies.
A Signal Correlation Guided ATPG solver and its applications for solving difficult industrial cases

The developments of efficient SAT solvers have attracted tremendous research interest in recent years. The merits of these solvers are often compared in terms of their performance based upon a wide spread of benchmarks. In this paper, we extend an earlier-proposed solver design concept called (SCGL) Signal Correlation Guided Learning that is ATPG-based into a family of heuristics. Along with this SCGL family of heuristics, we classify benchmark examples according to their performance using the SCGL heuristics. With this study, we identify the class of problems that are uniquely suitable to be solved by using the SCGL approach. In particular, for solving difficult circuit-based problems at INTEL, our SCGL-based ATPG solver is able to achieve at least an order of magnitude speedup over the state-of-the-art SAT solvers. Our conclusion is that SCGL is an unique solver design concept that can complement heuristics proposed by others for solving circuit-oriented difficult problems.
The effect of Medicaid adult vision coverage on the likelihood of appropriate correction of distance vision: Evidence from the National Health and Nutrition Examination Survey.

Abstract Background Medicaid is the main public health insurance program for individuals with low income in the United States. Some state Medicaid programs cover preventive eye care services and vision correction, while others cover emergency eye care only. Similar to other optional benefits, states may add and drop adult vision benefits over time. Research objective This article examines whether providing adult vision benefits is associated with an increase in the percentage of low-income individuals with appropriately corrected distance vision as measured during an eye exam. Methodology We estimate the effect of Medicaid vision coverage on the likelihood of having appropriately corrected distance vision using examination data from the 2001–2008 National Health and Nutrition Examination Survey. We compare vision outcomes for Medicaid beneficiaries (n = 712) and other low income adults not enrolled in Medicaid (n = 4786) before and after changes to state vision coverage policies. Findings Between 29 and 33 states provided Medicaid adult vision benefits during 2001–2008, depending on the year. Our findings imply that Medicaid adult vision coverage is associated with a significant increase in the percentage of Medicaid beneficiaries with appropriately corrected distance vision of up to 10 percentage points. Conclusion Providing vision coverage to adults on Medicaid significantly increases the likelihood of appropriate correction of distance vision. Further research on the impact of vision coverage on related functional outcomes and the effects of Medicaid coverage of other services may be appropriate.
‘Blood and treasure’: exiting the Great Depression and lessons for today

Although avoiding the policy mistakes of the 1930s helped define how policy-makers responded to the 2007-8 financial crisis and ensuing recession, policy applications to the recovery phase are less well understood. We draw on the experience of the US in the 1930s to shed light on exit strategies—movements back to institutional conditions associated with steady-state growth, including stable inflation and broadly non-interventionist credit- and capital-market policies. We describe how policy responses to the deflation and banking crises of the 1930s coloured the exit policy debate after the Great Depression. We show that a full exit from the Great Depression, defined as the point at which interventionist credit- and capital-market policies and institutions were wound down did not occur in the 1930s. It took until the 1950s for this to occur and for the Federal Reserve to regain its independence and return unfettered to its longer-run