cssi/SciSciGPT-SciSciNet huggingface dataset:
The exocytotic fusion pore and neurotransmitter release

Membrane fusion is ubiquitous in biological systems, occurring in the simplest of unicellular eukaryotes as well as higher eukaryotes. As soon as the first primitive eukaryotic cell utilized a lipid bilayer as an outer membrane, membrane fusion (and fission) became necessary for the traffic of material from the outside to the inside, the inside to the outside, and between different intracellular membrane-bounded compartments. The earliest cells would have made use of the intrinsic ability of lipid bilayers to fuse under certain conditions. Although this fusogenic property of bilayers has been known for some time, it is has become clear only relatively recently that two phospholipid bilayers will fuse spontaneously, owing to a hydrophobic force, when the bilayers are brought close together under conditions of membrane tension or high curvature (Helm and Israelachvili, 1993). The primeval cell would have used proteins to develop the appropriate architecture in which such fusion would occur in a regulated manner. During the course of evolution, ever more sophisticated ways of regulating this basic process would evolve, but the underlying fusion mechanism would remain unchanged. We have proposed that a macromolecular scaffold of proteins is responsible for bringing the plasma membrane close to the secretory granule membranes and creating the architecture that enables the hydrophobic force to cause fusion (Figure 1; Nanavati et al., 1992; Monck and Fernandez, 1992; Oberhauser and Fernandez, 1993). Evidence is now accumulating that there are several highly conserved families of proteins associated with vesicle fusion events, from yeast to mammalian cells, and with intracellular traffic, as well as with regulated exocytosis and synaptic transmission (Bennett and Scheller, 1993; Sollner et al., 1993; Sudhof et al., 1993). The molecular structures (or scaffolds) that regulate membrane fusion are likely to contain related proteins and share certain fundamental properties.
Effect of filtration on antimicrobial solutions.

Abstract The effect of filtering 20 antimicrobial solutions through four types of membrane filters was examined. Essentially, all antimicrobial activity was recovered after the solutions were filtered.
Conductivity and nuclear spin relaxation in superionic glasses, polymer electrolytes and the new polymer-in-salt electrolyte☆

Abstract The phenomenology of electrical relaxation in superionic glasses and their melts, and in salt-in-polymer electrolytes is reviewed, and then recent observations on nuclear spin lattice relaxation of mobile species like 7 Li + are examined in the same conceptual frame work are examined. To shed light on the origin of difference found in superionic glasses between the correlation times, τ c , for fluctuations causing spin lattice relaxation and those, τ σ , allowing conductivity relaxation, 7 Li nuclear spin resonance was studied across a binary liquid system of [polypropylene oxide + Li salt(s)]. In the polymer-rich solutions, the two correlation times are found to have the same value but above the (salt-in-polymer) (ppolymer-in-salt) boundary, a gap starts to open up. The value of T 1 at its minimum is found to be almost independent of solution composition, implying that the Li + cations find comparable sites as polymer replaces salt in the solution, To observed the behavior in polymer-free salt melts, salt mixtures had to be used to gain access to the viscous liquid regime. The study of such liquid salts reveals a difference in τ c and τ σ of 1.1 orders of magnitude, comparable to that found in glassy superionics. The results are discussed in terms of the serial decoupling of different relaxation modes observed in fragile liquids during cooling towards the glass transition, and are used to support the assertion that conductivity in the ‘polymer-in-salt’ electrolytes is dominated by Li + migration.
An improved model for the strain dependence of the superconducting properties of Nb3Sn

We propose an improved model for the strain dependence of the superconducting properties of Nb{sub 3}Sn. The model is based on the three dimensional strain tensor and derived in terms of the first, second and third invariants, and improves an existing model that only includes the second invariant. The axial form of the new model accurately accounts for the experimentally observed dependence of the effective upper critical magnetic field (H*{sub c2}) on axial strain, i.e. a quasi-parabolic strain dependence, asymmetry, and an upturn at large compressive axial strain. An accurate model that accounts for the three dimensional nature of strain is important for scaling relations for the critical current that are used to model magnet performance based on wire measurements.
Minimalistic Predictor of Protein Binding Energy: Contribution of Solvation Factor to Protein Binding

It has long been known that solvation plays an important role in protein-protein interactions. Here, we use a minimalistic solvation-based model for predicting protein binding energy to estimate quantitatively the contribution of the solvation factor in protein binding. The factor is described by a simple linear combination of buried surface areas according to amino-acid types. Even without structural optimization, our minimalistic model demonstrates a predictive power comparable to more complex methods, making the proposed approach the basis for high throughput applications. Application of the model to a proteomic database shows that receptor-substrate complexes involved in signaling have lower affinities than enzyme-inhibitor and antibody-antigen complexes, and they differ by chemical compositions on interfaces. Also, we found that protein complexes with components that come from the same genes generally have lower affinities than complexes formed by proteins from different genes, but in this case the difference originates from different interface areas. The model was implemented in the software PYTHON, and the source code can be found on the Shakhnovich group webpage: http://faculty.chemistry.harvard.edu/shakhnovich/software.
An improved upper bound on the block coding error exponent for binary-input discrete memoryless channels (Corresp.)

The recent upper bounds on the minimum distance of binary codes given by McEliece, Rodemich, Rumsey, and Welch are shown to result in improved upper bounds on the block coding error exponent for binary-input memoryless channels.
Metamaterial coatings for broadband asymmetric mirrors

We report the design and fabrication of nanostructured metal-dielectric mirrors with high reflectance asymmetries in the visible spectral range. Applying dispersion engineering principles to model a broadband and large reflectance asymmetry, we obtain a dielectric function for this metamaterial, closely resembling the effective permittivity of disordered metal-dielectric nanocomposites. Coatings realized by using disordered nanocrystalline silver films on glass substrates confirm the theoretical predictions, exhibiting symmetric transmittance, accompanied by large broadband reflectance asymmetries.
Weighted Position and Motion Vector Consensus of Tropical Cyclone Track Prediction in the Western North Pacific

Abstract Two approaches are developed and tested to improve the unweighted position consensus for 96-, 108-, and 120-h tropical cyclone track guidance in the western North Pacific. A weighted position guidance technique uses a weighting factor for each model that is inversely proportional to how far the 60-, 66-, and 72-h positions of that model are from the corresponding positions of the 11-member position consensus. The weighted position consensus of 96-, 108-, and 120-h track errors for a sample of 24 storms during the 2006 season are consistently smaller than for the unweighted position consensus. In the second approach, a weighted motion vector consensus is developed that uses the same weighting factors as in the weighted position consensus, except that the weights are applied to 12-h motion vectors between 84 and 120 h. This weighted motion vector consensus has substantially smaller errors than the unweighted position consensus, and results in smoother tracks when one or more of the model tracks dro...
Microbial degradation of chloroethenes in groundwater systems

The chloroethenes, tetrachloroethene (PCE) and trichloroethene (TCE) are among the most common contaminants detected in groundwater systems. As recently as 1980, the consensus was that chloroethene compounds were not significantly biodegradable in groundwater. Consequently, efforts to remediate chloroethene-contaminated groundwater were limited to largely unsuccessful pump-and-treat attempts. Subsequent investigation revealed that under reducing conditions, aquifer microorganisms can reductively dechlorinate PCE and TCE to the less chlorinated daughter products dichloroethene (DCE) and vinyl chloride (VC). Although recent laboratory studies conducted with halorespiring microorganisms suggest that complete reduction to ethene is possible, in the majority of groundwater systems reductive dechlorination apparently stops at DCE or VC. However, recent investigations conducted with aquifer and stream-bed sediments have demonstrated that microbial oxidation of these reduced daughter products can be significant under anaerobic redox conditions. The combination of reductive dechlorination of PCE and TCE under anaerobic conditions followed by anaerobic microbial oxidation of DCE and VC provides a possible microbial pathway for complete degradation of chloroethene contaminants in groundwater systems.
Proteome analyses using accurate mass and elution time peptide tags with capillary LC time-of-flight mass spectrometry

We describe the application of capillary liquid chromatography (LC) time-of-flight (TOF) mass spectrometric instrumentation for the rapid characterization of microbial proteomes. Previously (Lipton et al., Proc. Natl. Acad. Sci. U.S.A.2002,99, 11049) the peptides from a series of growth conditions of Deinococcus radiodurans have been characterized using capillary LC MS/MS and accurate mass measurements which are captured as an accurate mass and time (AMT) tag database. Using this AMT tag database, detected peptides can be assigned using measurements obtained on a TOF due to the additional use of elution time data as a constraint. When peptide matches are obtained using AMT tags (i.e., using both constraints) unique matches of a mass spectral peak occurs 88% of the time. Not only are AMT tag matches unique in most cases, the coverage of the proteome is high; ∼3500 unique peptide AMT tags are found on average per capillary LC run. From the results of the AMT tag database search, ∼900 ORFs detected using LC-TOFMS, with ∼500 ORFs covered by at least two AMT tags. These results indicate that AMT database searches with modest mass and elution time criteria can provide proteomic information for approximately one thousand proteins in a single run of <3 h. The advantage of this method over using MS/MS based techniques is the large number of identifications that occur in a single experiment as well as the basis for improved quantitation. For MS/MS experiments, the number of peptide identifications is severely restricted because of the time required to dissociate the peptides individually. These results demonstrate the utility of the AMT tag approach using capillary LC-TOF MS instruments, and also show that AMT tags developed using other instrumentation can be effectively utilized.
The anti-Ramsey number of perfect matching

An r-edge coloring of a graph G is a mapping h:E(G)->[r], where h(e) is the color assigned to edge [email protected]?E(G). An exactr-edge coloring is an r-edge coloring h such that there exists an [email protected]?E(G) with h(e)=i for all [email protected]?[r]. Let h be an edge coloring of G. We say G is rainbow if no two edges in G are assigned the same color by h. The anti-Ramsey number, AR(G,n), is the smallest integer r such that for any exact r-edge coloring of K"n there exists a subgraph isomorphic to G that is rainbow. In this paper we confirm a conjecture of Fujita, Kaneko, Schiermeyer, and Suzuki that states AR(M"k,2k)=max{2k-32+3,k-22+k^2-2}, where M"k is a matching of size k>=3.
Defect evolution in graphene upon electrochemical lithiation.

Despite rapidly growing interest in the application of graphene in lithium ion batteries, the interaction of the graphene with lithium ions and electrolyte species during electrochemical cycling is not fully understood. In this work, we use Raman spectroscopy in a model system of monolayer graphene transferred on a Si(111) substrate and density functional theory (DFT) to investigate defect formation as a function of lithiation. This model system enables the early stages of defect formation to be probed in a manner previously not possible with commonly used reduced graphene oxide or multilayer graphene substrates. Using ex situ and Ar-atmosphere Raman spectroscopy, we detected a rapid increase in graphene defect level for small increments in the number of lithiation/delithiation cycles until the I(D)/I(G) ratio reaches ∼1.5–2.0 and the 2D peak intensity drops by ∼50%, after which the Raman spectra show minimal changes upon further cycling. Using DFT, the interplay between graphene topological defects and c...
Human cord blood γδ T cells expressing public Vγ2 chains dominate the response to bisphosphonate plus interleukin‐15

Compared with adults, the circulating Vγ2Vδ2 T-cell population in cord blood is present at low levels and does not show the strong bias for Vγ2-Jγ1.2 rearrangements. These features may be a result of limited exposure to stimulatory phosphoantigens, lack of T-cell-derived interleukin-2 (IL-2) or both. In cord blood mononuclear cell cultures, a single round of stimulation, using aminobisphosphonates to elevate phosphoantigen levels, resulted in expansion of adult-like Vγ2 chains and accumulation of memory cells with cytotoxic potential. Selection was similar using IL-2 or myeloid-derived IL-15. The Vγ2Vδ2 T cells present in neonates are capable of generating potent immune responses even when relying on IL-15.
Equilibrium spreading pressure and Langmuir–Blodgett film formation of omega-substituted palmitic acids

Abstract Langmuir–Blodgett isotherms and equilibrium spreading pressures were measured for compounds of the series X–(CH2)15COOH, X = CH3, SH, OH, F, Cl, Br. Only the CH3 and F terminated compounds formed monolayers with sufficient stability for accurate isotherm measurement, film transfer and X-ray photoelectron spectroscopic analysis. The presence of the terminal heteroatom substituents significantly diminished the stability of the L–B film and depressed the equilibrium spreading pressures (20 °C) from 15.4 mN/m for the CH3 terminated compound to a range of 0.95 to 0.08 mN/m for the other members of the series. These characteristics are attributed to the monolayer film being in a metastable state and the dipole moment of the heteroatom terminal group increasing the monolayer film kinetic instability by facilitating the formation of three-dimensional structures.
Archaebacterial ether lipids: Natural tracers of biogeochemical processes

Abstract Methanogen ether lipids have been quantified in sediments from a Florida swamp and the Atlantic ocean. Swamp cores containing acyclic and monocyclic isopranyl ethers are clearly differentiated from deep sea sediments which also contain bicyclic compounds. A concentration maximum near the bottom of the sulfate reducing zone in deep sea sediments may reflect a biogeochemical system in which methanogenesis and sulfate reduction are coupled by the process of methane oxidation. Lipid diagenesis is evident in the deep sea sediments. Species zonation, possibly caused by oxygen sensitivity, is detected in the relative lipid abundances in swamp sediments.
Regulation and expression of the bacteriophage mu mom gene: mapping of the transactivation (dad) function to the C region.

Abstract Expression of the bacteriophage Mu mom gene is under tight regulatory control. One of the factors required for mom gene expression is the (trans-acting function (designated Dad) provided by another Mu gene. To facilitate studies on the signals mediating mom regulation, we have constructed a mom-lacZ fusion plasmid which synthesizes β-galactosidase only when the Mu Dad transactivating function is provided. λpMu phages carrying different segments of the Mu genome have been assayed for their ability to transactivate β-galactosidase expression by the fusion plasmid. The results of these analyses indicated that the Dad transactivation function is encoded between the leftmost EcoRI site and the lys gene of Mu; this region includes the C gene, which is required for expression of all Mu late genes. Cloning of an approx. 800-bp fragment containing the C gene produced a plasmid which could complement MuC− phages for growth and could transactivate the mom-lacZ fusion plasmid to produce β-galactosidase. These results suggest that the C gene product mediates the Dad transactivation function.
Drosophila S2 cells: an alternative infection model for Listeria monocytogenes.

Summary Listeria monocytogenes is a Gram-positive facultative intracellular bacterial pathogen that infects humans and animals. Its pathogenic strategy involves the expression of virulence proteins that mediate intracytosolic growth and cell-to-cell spread. A key virulence protein is the cholesterol-dependent cytolysin, listeriolysin O (LLO), which is largely responsible for mediating escape from the phagosome into the host cytosol. To study further the host processes exploited during L. monocytogenes infection, we sought to develop Drosophila S2 cells as a model for infection. Here, we show that S2 cells share a number of properties with mammalian cell culture models of infection. As with mouse macrophages, LLO was required for phagosomal escape from S2 cells. Furthermore, vacuolar escape was dependent on their acidification via the ATPase proton pumps, as bafilomycin A 1 treatment sharply decreased escape. However, unlike in mouse macrophages, LLO mutants replicated in the phagosome of S2 cells. Drosophila cells are cholesterol auxotrophs, and exogenous cholesterol increased the infection rate of L. monocytogenes (LLO independent) and also augmented the efficiency of vacuolar escape (LLO dependent). With available genetic tools such as RNA interference, S2 cells could become an important model in the study of host–pathogen interactions.
Effect of ambient temperature on metabolic rate after thermal injury.

Objective The authors describe the effect of ambient temperature on metabolic rate after thermal injury. Summary Background Data Thermal injury induces a hypermetabolic state, which is reported to increase with the extent of burn. The magnitude of this response is further influenced by ambient temperature. Methods The resting energy expenditure was measured by indirect calorimetry at ambient temperatures of 22, 28, 32, and 35 C. It was indexed to a calculated basal metabolic rate in normal volunteers and adult patients with burns involving at least 20% of the total body surface area who had no evidence of systemic infection. These measurements were performed between postburn days 6 and 21. Results The effect of ambient temperature on metabolic rate was measured in 44 burn patients and 8 normal volunteers. Burn size ranged from 20 to 97% total body surface area with a mean of 44 ± 18.5% total body surface area. Metabolic rate did not change significantly in control subjects as ambient temperature was varied (p < 0.05). Regression analysis showed that burn size and ambient temperature were significant determinants (p < 0.01) of metabolic rate in the patients and that together these factors accounted for 55% of the variation observed (df adj. r 2 = 0.55) across the range of ambient temperatures studied. Metabolic rate was independent of burn size at ambient temperatures of 32 and 35 C (p < 0.02) and increased by a factor of 1.5 X basal metabolic rate. A further increase in metabolic rate, which was positively correlated with burn size, resulted from nonshivering thermogenesis at ambient temperatures 28 and 22 C. The magnitude of this response was greatest at 22 C. Conclusions These findings suggest that the hypermetabolic response to thermal injury is maximal in burns as small as 20% total body surface area and that an additional burn size-dependent increase in metabolic rate results from heat loss at ambient temperatures below thermoneutrality.
Effect of sugar and fat on the acceptability of vanilla ice cream

Abstract University students (73 men and 73 women) tasted and rated on a nine-point hedonic scale the texture and mouthfeel, flavor (taste and odor), and overall degree of liking for nine samples of vanilla ice cream varying in sugar (8.94 to 18.81%, wt/wt) and fat (8.73 to 19.30%, wt/wt) contents. Sugar consisted of 6% corn syrup solids [36 DE (dextrose equivalent)]; the balance was sucrose. Hedonic ratings differed significantly among samples, and the best-liked sample for texture and mouthfeel, flavor, and overall degree of liking contained 13.54% sugar and 14.99% fat. Men and women differed significantly in their liking of the flavor of the samples; men rated the flavor of the ice creams higher than did women. There was no gender difference for degree of liking of texture and mouthfeel or for overall degree of liking. Response surface methodology was used to relate hedonic ratings to sugar and fat percentages in the ice cream. Dome-shaped response surfaces were obtained for all three degree of liking parameters, and optimal sugar and fat, respectively, were 13.16% and 14.02% for degree of liking of texture and mouthfeel, 14.07% and 15.35% for degree of liking of flavor, and 14.30% and 14.77% for overall degree of liking. The response surfaces indicated that the level of sugar had a greater effect on all hedonic measures than did fat.
Success and Failure of Crossbred Cows in India: A Place-Based Approach to Rural Development

Although India's cooperative dairying program is lauded as a model of successful rural development, lack of uniformity in replication of the program across rural India has raised questions about the meanings of success. Differences between dairy cooperatives become especially apparent when crossbred cows are considered, so that the promotion of crossbreds by dairy development agencies has not always resulted in their actual adoption by farmers. This article seeks to explain the mixed reception accorded to crossbred cows by focusing on the link between development and place. By discussing both official discourses and local perspectives, the article enables two kinds of understanding of dairy development. First, the rise and fall of support for crossbred cows within India's national plans suggest that contrasts between official policies and local practices of dairying need to be attentive to the dynamics of both discourses and places. Second, the comparison between two villages—one utilizing crossbred cows ...
Das polarographische Verhalten von Ti(III) und Ti(IV) in Äthylendiamintetraazetat

Ti(III) and Ti(IV) form complexes, at pH values of under 2.5, with ethylene di-amino-tetra-acetate (Y−4) with the probable formula TiY− and TiY, which are reduced reversibly and independantly of pH at the dropping Hg-electrode. Temporary values are given for the dissociation constants. At higher pH values, the electrode processes are irreversible and dependant on Ph. From this fact, and from the decrease in wave height, the presence of complexes containing oxygen and numerous nuclei is concluded.
An in vitro assay for entry into cilia reveals unique properties of the soluble diffusion barrier

Specific proteins are concentrated within primary cilia, whereas others remain excluded. To understand the mechanistic basis of entry into cilia, we developed an in vitro assay using cells in which the plasma membrane was permeabilized, but the ciliary membrane was left intact. Using a diffusion-to-capture system and quantitative analysis, we find that proteins >9 nm in diameter (∼100 kD) are restricted from entering cilia, and we confirm these findings in vivo. Interference with the nuclear pore complex (NPC) or the actin cytoskeleton in permeabilized cells demonstrated that the ciliary diffusion barrier is mechanistically distinct from those of the NPC or the axon initial segment. Moreover, applying a mass transport model to this system revealed diffusion coefficients for soluble and membrane proteins within cilia that are compatible with rapid exploration of the ciliary space in the absence of active transport. Our results indicate that large proteins require active transport for entry into cilia but not necessarily for movement inside cilia.
An electrophysiological study of the in vitro, perfused brain stem‐cerebellum of adult guinea‐pig.

1. We describe here a technique which allows the long-term in vitro survival of the perfused isolated brain stem-cerebellum of adult guinea-pig. The viability of this preparation was assessed by comparing the electrophysiological properties of individual neurones and of neuronal pools to those obtained in vivo or in brain slices. The areas investigated included the cerebellar cortex, the inferior olive and the pontine nuclei. 2. Cerebellar field potential and intra- and extracellular single-cell recordings could be obtained for as long as 15 h after the preparation was initially isolated. The waveforms of field potentials recorded at various depths in the cerebellar cortex following surface folial stimulation were similar to those recorded in vivo. Extracellular recordings from single Purkinje cells following white matter stimulation demonstrated antidromic as well as mossy- and climbing fibre-mediated excitation. Stimulation of the cerebellar surface elicited orthodromic parallel fibre excitation of Purkinje cells and basket-stellate and Golgi cell inhibition. 3. Intrasomatic and intradendritic recordings from Purkinje cells reproduced all the phenomenology described earlier under in vivo conditions and in vitro slice preparations. In addition, spontaneous excitatory synaptic potentials generating simple spikes (mossy fibre-parallel fibre-mediated activity) and complex spikes (climbing fibre-mediated activity) were consistently observed. 4. Extracellular field potentials and extra- and intracellular recordings from inferior olive neurones were similar to those previously shown for the mammalian inferior olive. 5. Intracellular recordings were also obtained from pontine nuclei neurones, a major source of mossy fibre afferents to the cerebellum. Stimulation of the contralateral superior cerebellar peduncle produced antidromic invasion of these neurones whereas stimulation of the ipsilateral inferior cerebral peduncle resulted in their orthodromic activation. 6. The preparation responded to pharmacological challenge in a manner which demonstrated a sequential activation of sets of synaptic links in a given pathway. Thus, harmaline generated oscillations of inferior olivary neurones which were similar to those observed in vivo and which produced climbing fibre EPSPs in Purkinje cells at the same frequency as the inferior olivary oscillations. Climbing fibre activation of the Purkinje cells generated powerful inhibitory potentials in the cerebellar nuclear neurones at the same frequency.(ABSTRACT TRUNCATED AT 400 WORDS)
The need to reexamine axillary lymph node dissection in invasive breast cancer.

The manuscript by Silverstein et al.’ is most timely and pertinent in the continuing evolution of tissue conservation in the management of patients with breast cancer. There has been general acceptance over the past two decades that breast preservation rather than mastectomy is appropriate treatment for the majority of cases of primary invasive breast cancer and most cases of small mammographically detected duct carcinoma in situ (DCIS). The next conventional surgical operation to reappraise in the management of patients with invasive breast cancer is axillary lymph node dissection, which, incidentally, has already been abandoned for DCIS because of the extremely low rate of lymph node metastasis.* As the authors stated, ”it may now be time to consider eliminating routine node dissection for lesions more advanced than DCIS, but with extremely low likelihood of axillary node involvement.”’ The authors concluded that a 3% incidence of axillary metastasis, as they reported, is too low to justify the morbidity and expense of a procedure that mandates a hospital admission, general anesthesia, and a total cost of perhaps $10,000, including charges for the operating room, recovery room, hospital room, surgeon, and anesthesiologist.’ Silverstein et al. stated, “How can we justify 100 node dissections in an attempt to find three patients with positive nodes to treat with chemotherapy, one of whom, at most, will be helped?”’ The authors beg the question of how the threshold of probability of axillary lymph node metastasis should be set so that axillary lymph node dissection is of such low yield that it does not justify the high cost, morbidity, possibility of arm edema, and, particularly, the marginal gain from the use of adjuvant systemic therapy. Is a 10% or 20% threshold rate of axillary metastases low enough to justify not doing a dissection? This becomes an exercise in analyzing risk:benefit ratios. For example, a 15% rate of
Dilepton production from pion annihilation in a realistic Delta -hole model.

Dilepton production from {pi}{sup +}{pi}{sup {minus}} annihilation in nuclear matter is calculated in a simple two-level Delta-hole model and a more realistic model including both real pions and nucleon-hole and Delta-hole excitations. Substantial enhancement of the dilepton yield is found in the invariant mass region {ital M}{lt}250 MeV/{ital c}{sup 2} due to annihilation of noncollective low-energy high-momentum nucleon-hole modes having a (very) small pion component. The inclusion of a finite temperature in the dispersion relation does not affect the total dilepton yield much, although it causes significant redistribution of the contributions from the various combinations of pionic modes.
Effects of endotoxin on immunity in aging mice.

Abstract In vivo administration of bacterial lipopolysaccharides (LPS) to young adult mice causes a dose-dependent depression of antibody formation. In contrast, LPS produced no effects on the responses of older mice and these animals appeared to be refractory to the depressive effects observed in the young adults. When young adults were pretreated with endotoxin their baseline control responses were also severely depressed and the LPS response profile resembled that of the normal 9-month-old animals. These results suggest that endotoxin effects may contribute to the genesis of immune abnormalities in the aged.
DISORDER AND DECAY The Concept and Measurement of Perceived Neighborhood Disorder

The authors develop and assess a scale of perceived neighborhood disorder. The scale of neighborhood disorder has high reliability, external validity, and shows interesting distinctions, and overlaps between physical and social disorder. It also shows that order and disorder are two ends of a single continuum.
The moderating effects of political skill on the perceived politics–outcome relationships

Summary Previous research has established that perceptions of organizational politics are associated with negative organizational outcomes. However, this may not hold true for all individuals. We offer subordinate and supervisor political skill, the ability to understand interactions at work and to use that understanding to effectively influence others, as possible moderators. Specifically, this study investigates the impact of both employees’ self-rated political skill and their managers’ political skill on job satisfaction, job performance, and manager-rated commitment. We examined these relationships in an organizational sample of 106 matched dyadic pairs and found mixed support for the joint moderating effect of self and manager political skill on the politics perceptions-outcome relationships. Strengths, limitations, and directions for future research are discussed. Copyright # 2010 John Wiley & Sons, Ltd.
Sampling effects, species-sediment relationships, and observed geographic distribution: An uppermost Cretaceous bivalve example

Abstract When bivalve specimens from Campanian and Maastrichtian age sediments in Europe are compared to speciesdocumented for similar sediments of the Atlantic and Gulf coastal Plain of North America, 78 species are recognized as being the same on both continents. The North American data set results from examination of 502 bulk collections and the european data set is based on examination of specimens from 61 locations which are housed in 12 European museums. A sampling effects model which accounts for the disparity in data set size, predicts that 115 rather than 78 of the 164 North American bivalve species should be found if the two data sets are in fact samples of the same fauna. The difference of 37 species is mainly attributed to species-sediment interaction and the fact that 15% of the North American collections are from carbonates whereas 77% of the European collections are from carbonates. When the sampling effect model uses species occurrence frequency for the 74 North American carbonate collections, the observed similarity values are close to those predicted. The model predicts 82–87 species and 75 species are observed. It can be concluded that species-sediment relationships are strong for these bivalve species, that the sampling effect model is valid if proper attention is given to the sediment make-up of the two data sets, and that the areal distribution of these bivalve species which lived just prior to the K/T boundary should be reanalyzed.
Nonlinear dynamical analysis of carbachol induced hippocampal oscillations in mice.

Hippocampal neuronal network and synaptic impairment underlie learning and memory deficit in Alzheimer's disease (AD) patients and animal models. In this paper, we analyzed the dynamics and complexity of hippocampal neuronal network synchronization induced by acute exposure to carbachol, a nicotinic and muscarinic receptor co-agonist, using the nonlinear dynamical model based on the Lempel-Ziv estimator. We compared the dynamics of hippocampal oscillations between wild-type (WT) and triple-transgenic (3xTg) mice, as an AD animal model. We also compared these dynamic alterations between different age groups (5 and 10 months). We hypothesize that there is an impairment of complexity of CCh-induced hippocampal oscillations in 3xTg AD mice compared to WT mice, and that this impairment is age-dependent. To test this hypothesis, we used electrophysiological recordings (field potential) in hippocampal slices. Acute exposure to 100 μmol/L CCh induced field potential oscillations in hippocampal CA1 region, which exhibited three distinct patterns: (1) continuous neural firing, (2) repeated burst neural firing and (3) the mixed (continuous and burst) pattern in both WT and 3xTg AD mice. Based on Lempel-Ziv estimator, pattern (2) was significantly lower than patterns (1) and (3) in 3xTg AD mice compared to WT mice (P<0.001), and also in 10-month old WT mice compared to those in 5-month old WT mice (P<0.01). These results suggest that the burst pattern (theta oscillation) of hippocampal network is selectively impaired in 3xTg AD mouse model, which may reflect a learning and memory deficit in the AD patients.
Apparel Retail Product Development: Model Testing and Expansion

The objectives of the study were to a) test the validity of Gaskill's (1992) Retail Product Development Model across a broader range of specialty stores and b) expand the model beyond line presentation to include events and considerations in post-adoption product development. Twenty-one men's, women's, and children's specialty store retailers deriving 70% to 100% of their sales from private label merchandise through in-house product development were compiled from current retail directories to serve as the sample. Data were collected with a qualitative telephone interview schedule and analyzed using descriptive analysis. Stages in the original model were confirmed; however, modifications were made based on new data. Expansion of the model to include post-adoption product development stages was also carried out. The end result was the development of a revised Retail Apparel Product Development Model.
The impact of age and gender on cardiac resynchronization therapy outcome.

Background:Cardiac resynchronization therapy (CRT) outcome varies significantly among patients. We aimed to determine the impact of age, gender, and heart failure etiology on the long-term outcome of patients receiving CRT. Methods:A total of 117 patients with drug-refractory heart failure, New York Heart Association (NYHA) Class III or IV, and a wide QRS complex, who received CRT, were followed for one year. Long-term outcome was measured as a combined end point of hospitalization for heart failure and/or all cause mortality. Efficacy of CRT was compared between men and women, between older and younger patients, and between patients with ischemic and nonischemic heart disease. Time to the primary end point was estimated by the Kaplan-Meier method and comparisons were made using the Breslow-Wilcoxon test. Results:Baseline clinical characteristics were comparable between gender, age, and heart failure etiology subgroups. There was no significant difference in the combined end point between older versus younger (age >70, (n = 71), versus age < 70, (n = 46), P = 0.52); both genders (men, n = 91 vs women, n = 26, P = 0.46) and etiology of the cardiomyopathy (ischemic (n = 79) vs nonischemic (n = 38), P = 0.12). Substratification of the genders by the etiology of the cardiomyopathy, showed that women with ischemic cardiomyopathy (IW, n = 10) had a trend to a worse outcome compared to the other groups i.e., nonischemic women (NIW, n = 16), ischemic men (IM, n = 69), and nonischemic men (NIM, n = 22), P = 0.04. After adjusting for potential covariates, a Cox regression analysis showed no significant difference between the groups (P = 0.61). Conclusions:CRT outcome appears independent of age, gender, and heart failure etiology in this single institution study.
A comparison of the full-wave and WKB solutions of a plane wave with impulsive time variation reflected from a sech 2 electron-density profile

This communication compares a more general numerical point-to-point transient wave propagation program to a known analytical (full-wave) solution based upon a certain special geometry and ionospheric profile. The main purpose of the comparison is that of using the known analytical results as a test case for the numerical program. The parameters of the ionosphere were chosen to purposively tax the condition of requiring a slowly varying medium in using the Wentzel-Kramer-Brillouin (WKB) method (i.e., the parameters chosen lead to a sporadic E -type layer). With the results favorable for this case, the application of a numerical procedure, based upon the WEB method, to the more slowly varying F region would definitely be acceptable. Based upon the full-wave and WKB solutions, results are given in the form of time-domain waveforms due to reflection of a transient wave from the ionosphere.
On tone-burst measurements of sound speed and attenuation in sandy marine sediments

During the Sediment Acoustics Experiment in 1999 (SAX99), the in Situ Sediment geoAcoustic Measurement System (ISSAMS), transmitting tone bursts containing an integer number of cycles, was used to measure the speed and attenuation of compressional waves in a weakly dispersive, medium-sand sediment in the Gulf of Mexico. ISSAMS was deployed at seven stations and operated mostly at a frequency of 38 kHz, but at two of the sites, a succession of pulses was transmitted with frequencies extending from 25 to 100 kHz, in 5-kHz increments, yielding the phase speed, the group speed and the attenuation as a function of frequency. An analysis of a tone-burst transmission in a dispersive medium illustrates that several subtle factors, including the narrow bandwidth of the source, along with dispersion and attenuation in the medium, have the potential for introducing significant errors into travel-time measurements. It is concluded that, in general, the timing is best performed between two receivers rather than between the source and a receiver, the difficulty in the latter case being that the output from a narrow-band source is not a replica of the input. A correlation applied to the arrivals at the two receivers yields the travel time, from which a good approximation to the group speed is immediately available. Alternatively, a Fourier decomposition yields the phase speed as a function of frequency, which would be an advantage in a highly dispersive medium. The two techniques return almost identical wave speeds when applied to the ISSAMS tone-burst data from the weakly dispersive SAX99 sediments: at 38 kHz, the mean wave speed from the six primary stations is 1778 m/s. Attenuation was also estimated from receiver-to-receiver travel paths, using three different techniques: the ratio of the mean-square values of the arrivals, the ratio of the Fourier magnitudes of the arrivals and transposition. All three methods yield similar results when applied to the SAX99 data, returning a mean attenuation from the six stations of 12 dB/m at 38 kHz, which is comparable with previously reported measurements of attenuation in marine sands. From the broadband measurements, between 25 and 100 kHz, the dispersion is found to be weak but detectable and the attenuation scales almost linearly with frequency, which corresponds to a nearly constant Q.
Nucleotide phosphatase in Strongylocentrotus purpuratus eggs. II. Reactivation, substrate specificity, activators, and inhibitors.

A medullary nucleotide phosphatase activity can be demon-strated in fixed mature S. purpuratus eggs. However, this enzymatic activity is lost from eggs stored for more than four days in a Michaelis buffer prepared in distilled water. The activity can be reinstituted by overnight incubation in sea water or solutions of its major cations, prior to reacting for enzymatic activity. The substrate characteristics of this nucleotide phosphatase system indicate that the activity is not due to nonspecific acid or alkaline phosphatases, organic or inorganic pyrophosphatases, or hexose phosphatases. The activity is present with ATP and other nucleoside tri-, di-, and monophosphates and is most accurately labelled as a nucleotide phosphatase. The effects of various selected enzymatic activators and inhibitors upon the nucleotide phosphatase activity, demonstrated with ATP as substrate, are also presented. This activity is inhibited by L-cysteine, glutathione, sodium fluoride, sodium tartrate, and zinc chloride; not inhibited by p-chloromercuribenzoic and mersalyl acids; and stimulated by 2,4-dinitrophenol, sodium azide, iodo-acetamide, and ouabain. These data indicate some similarities with other phosphatases, but there are discriminating differences which label the enzyme system as a distinct entity.
Algebras of discrete event models

The authors consider discrete event models (DEMs) that describe logical system behavior, i.e. mathematical models that represent the set of traces of sequences of events that the system can execute. Examples of DEM formalisms include state machines, Petri nets, and Hoare's communicating sequential processes. All these formalisms are algebras, i.e. a set of models together with operators that combine models to form other models in ways in which real systems are interconnected. A general approach toward constructing model algebras is proposed. The approach covers both deterministic and nondeterministic models, and it can be tailored to recover existing formalisms and to obtain model families. >
High-throughput screen for genes predominantly expressed in the ICM of mouse blastocysts by whole mount in situ hybridization.

Abstract Mammalian preimplantation embryos provide an excellent opportunity to study temporal and spatial gene expression in whole mount in situ hybridization (WISH). However, large-scale studies are made difficult by the size of the embryos (∼60 μm diameter) and their fragility. We have developed a chamber system that allows parallel processing of embryos without the aid of a microscope. We first selected 91 candidate genes that were transcription factors highly expressed in blastocysts, and more highly expressed in embryonic (ES) than in trophoblast (TS) stem cells. We then used the WISH to identify 48 genes expressed predominantly in the inner cell mass (ICM) and to follow several of these genes in all seven preimplantation stages. The ICM-predominant expressions of these genes suggest their involvement in the pluripotency of embryonic cells. This system provides a useful tool to a systematic genome-scale analysis of preimplantation embryos.
Platelet endothelial cell adhesion molecule deficiency or blockade significantly reduces leukocyte emigration in a majority of mouse strains

PECAM is a molecule used specifically during the diapedesis step when neutrophils and monocytes leave the blood compartment. Anti-PECAM reagents, such as Abs and soluble fusion proteins, block diapedesis both in vivo and in vitro. However, the PECAM knockout mouse in C57BL/6 strain has no serious defects in most models of inflammation. We show in this study that the same PECAM knockout backcrossed into the FVB/n strain clearly has reduced leukocyte emigration in two models of inflammation. Furthermore, we show that anti-PECAM reagents can block leukocyte emigration in several other wild-type strains of mice like FVB/n, SJL, and the outbred strain Swiss Webster. This clearly shows that the C57BL/6 strain is uniquely able to compensate for the loss of PECAM function. Murine models of inflammatory disease that have been studied using C57BL/6 mice should be re-evaluated using FVB/n or other mouse strains to determine whether PECAM plays a role in those models.
The GATA transcription factor/MTA-1 homolog egr-1 promotes longevity and stress resistance in Caenorhabditis elegans

Aging is associated with a large number of both phenotypic and molecular changes, but for most of these, it is not known whether these changes are detrimental, neutral, or protective. We have identified a conserved Caenorhabditis elegans GATA transcription factor/MTA-1 homolog egr-1 (lin-40) that extends lifespan and promotes resistance to heat and UV stress when overexpressed. Expression of egr-1 increases with age, suggesting that it may promote survival during normal aging. This increase in expression is dependent on the presence of the germline, raising the possibility that egr-1 expression is regulated by signals from the germline. In addition, loss of egr-1 suppresses the long lifespan of insulin receptor daf-2 mutants. The DAF-16 FOXO transcription factor is required for the increased stress resistance of egr-1 overexpression mutants, and egr-1 is necessary for the proper regulation of sod-3 (a reporter for DAF-16 activity). These results indicate that egr-1 acts within the insulin signaling pathway. egr-1 can also activate the expression of its paralog egl-27, another factor known to extend lifespan and increase stress resistance, suggesting that the two genes act in a common program to promote survival. These results identify egr-1 as part of a longevity-promoting circuit that changes with age in a manner that is beneficial for the lifespan of the organism.
A Model for Optical Bistability in a Hybrid Semiconductor Photonic Crystal Structure

A new model for optical bistability in a photonic crystal structure closed to a semiconductor is presented. It is found that increase in the strength of self-interaction can destroy this nonlinear phenomenon whereas a small variation of this interaction from low initial value can control the area of the bistable loop.