cssi/SciSciGPT-SciSciNet huggingface dataset:
Acoustic gain and threshold improvement in hearing aid selection.

Unaided and aided spondee thresholds were obtained for 25 hearing-impaired subjects in order to examine the relationship between spondee threshold improvement and average acoustic gain developed by...
Analysis of spurious oscillation modes for the shallow water and Navier-Stokes equations

Abstract The origin and nature of spurious oscillation modes that appear in mixed finite element methods are examined. In particular, the shallow water equations are considered and a modal analysis for the one-dimensional problem is developed. From the resulting dispersion relations we find that the spurious modes in elevation are associated with zero frequency and large wave number (wavelengths of the order of the nodal spacing) and consequently are zero-velocity modes. The spurious modal behavior is the result of the finite spatial discretization. By means of an artificial compressibility and limiting argument we are able to resolve the similar problem for the Navier-Stokes equations. The relationship of this simpler analysis to alternative consistency arguments is explained. This modal approach provides an explanation of the phenomenon in question and permits us to deduce the cause of the very complex behavior of spurious modes observed in numerical experiments with the shallow water equations and Navier-Stokes equations. Furthermore, this analysis is not limited to finite element formulations, but is also applicable to finite difference formulations.
Studies on lysogeny in Escherichia coli with bacteriophage λ physical observation of the insertion process

Abstract The kinetics of insertion of λ DNA into a sex factor (F′450) carrying att λ ‡ was measured. It has been found that both interruption at att λ and insertion start at about 10 minutes after infection. For the first 30 minutes after infection there is a quantitative conversion of the original sex-factor covalent circles to circles containing one or more λ DNA molecules. At the end of 30 minutes about one-quarter of the F′450 circles are converted to these forms. The remaining F′450 circles continue to be lost, though at a lower rate, and practically none remains after 2 hours. However, the F′450 circles that are lost after this 30-minute period are not recovered as covalent circles. Only when cells are labeled at much later times (about 10 hours after infection) is full recovery of covalently sealed sex factors observed; nearly all of these show the insertion of at least one λ DNA molecule. It is found that int and b 2 mutants are neither able to insert nor interrupt the bacterial att , while N mutants are able to insert but to a lesser extent. Evidence is presented which suggests that most multiple prophages arise by a one-step insertion of multiple-size λ circles.
750 DISCREPANCY BETWEEN MINIMUM INHIBITORY CONCENTRATION (MIC) AND MINIMUM BACTERICIDAL CONCENTRATION (MBC) OF PENICILLIN DEMONSTRATED IN GROUP A (GAS) AND GROUP B |[beta]|- HEMOLYTIC STREPTOCOCCI (GBS)

A discrepancy between the MIC and the MBC of penicillin (pen) against GBS has been reported, suggesting that the relapses of GBS disease after treatment with conventional doses of pen may be a result of this discrepancy. In this study, we measured pen MIC and MBC levels against GBS and compared them with levels obtained for GAS, an organism that has been successfully treated for years with conventional doses of pen without evidence of relapse in normal hosts. These experiments confirmed the reports that a large MIC/MBC discrepancy exists in GBS(10 fold); however, a larger discrepancy exists for GAS(25 fold). These findings diminish the likelihood of clinical significance of the MIC/MBC ratio alone in accounting for the relative difficulty in treating GBS. Other factors, such as the lower absolute sensitivity of GBS to pen compared to that of GAS, must be playing a role: both the MIC and the MBC values were significantly higher for GBS than for GAS.
2-Arachidonoylglycerol is a substrate for butyrylcholinesterase: A potential mechanism for extracellular endocannabinoid regulation

2-Arachidonoylglycerol (2-AG) is a component of the endocannabinoid receptor pathway and is primarily hydrolyzed by monoacylglycerol lipase (MAGL) in vivo. We found that the non-specific serine esterase, butyrylcholinesterase (BChE), can hydrolyze 2-AG with reasonable affinity and may present a new compensatory mechanism for endocannabinoid regulation. In vitro hydrolysis reactions of 2-AG with equine BChE were analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS) positive/negative electrospray ionization (ESI±) to measure the formation of arachidonic acid (AA) and the loss of 2-AG over time (min). The resulting Michaelis-Menten approximations reveal that BChE has affinity towards 2-AG in phosphate buffer at neutral pH (7.4). The calculated Vmax, Km and kcat were 12.1nmols(-1), 57.5μM, and 0.074s(-1), respectively, which produced a diffusion-controlled rate of association (kcat/Km) of 1.3×10(3)M(-1)s(-1). Human BChE 2-AG hydrolysis was measured by immunoprecipitating BChE from fresh plasma and monitoring 2-AG loss and AA formation over time. These findings show that BChE can hydrolyze 2-AG which may be evidence of a more specific role for BChE in endocannabinoid regulation.
Metabolism of norethynodrel by rat liver

Abstract The incubation in vitro of norethynodrel with the postmitochondrial supernatant from rat liver results in the formation of three intermediary metabolites, namely the 3α- and 3β-hydroxy derivatives and norethindrone. These three steroids are further metabolized to more polar compounds thought to be polyhydroxylated end-products. Incubation of the polar products with glucuronidase and sulfatase suggests that these compounds exist as free steroids rather than as conjugates.
A successful model from Hawaii for rapid response to invasive species

Summary We outline a functional management model for the eradication of incipient populations of invasive species that avoids reliance on official governmental response. This model involves formation of informal multi-partner committees that utilise outside funding to achieve pest-management goals. We describe why such a system was needed in Hawaii, how it is structured, how it operates, its achievements, and its advantages and limitations. Fragmented and incomplete governmental authorities are currently the rule for invasive-species management in many parts of the world and typically lead to non-response or an ineffective response. The model we describe serves the useful function of allowing eradication of incipient pests to proceed while comprehensive biosecurity programs are devised through more traditional governmental channels.
Natural rubber latex-specific IgE antibodies in non-healthcare workers: comparison of two FDA-clearedin vitro kits

Latex-specific IgE antibody immunoassays are heavily relied upon in the diagnosis of latex allergy in the United States. The goal of this study is to compare anti-latex IgE levels measured by two U.S. Food and Drug Administration (FDA)-cleared kits (CAP® System and AlaSTAT® Microplate) in sera obtained from employees in non-healthcare industries. Sera were obtained from 381 workers employed in several, non-healthcare industries over the past 10 years, and stored frozen. All 381 coded sera were analysed for latex-specific IgE using the Diagnostic Products Corporation microplate AlaSTAT® and the Pharmacia-UpJohn CAP® System. Concordance between methods and intra- and inter-assay reproducibility were evaluated. Twenty-six sera gave positive results using the AlaSTAT® assay (26/381, 6.82%), while 24 yielded CAP® positive results (6.30%). There were no significant differences (p = NS) between the assays' measurements of latex-specific IgE antibody levels for all 381 sera, yielding 0.28 ± 0.19 kU L−1 and 0.34 ± 0.59 kUA L−1, respectively. AlaSTAT® and CAP® assays agreed on the positive status of 9 (9/381, 2.4%) sera, and the negative status of 340 sera (340/381, 89.2%). The assays yielded discordant results on some individual sera. CAP® discordant results occurred in 17/26 sera (65.4%) of AlaSTAT® positive sera, while AlaSTAT® discordant results were found in 15/24 (57.7%) of the CAP® positive sera. The CAP® System, for instance, detected 0.39–2.3 kUA l−1 (1.03 ± 0.59, [mean ± SD]) of latex-specific IgE in the serum from 15 individuals that were all AlaSTAT® negative. In contrast, the AlaSTAT® detected 0.36–1.6 kU l−1 (0.62 ± 0.31, [mean ± SD]) of IgE anti-latex in the serum from 17 subjects that were all CAP® negative. These data indicate that the a priori seroprevalence of latex-specific sera IgE is about 6%–7% in non-healthcare workers and that the CAP® and AlaSTAT® assays agree on the positive or negative status of the majority of sera (91.6%). However, caution should be exercised when applying FDA-cleared in vitro assays for latex-specific sera IgE in populations known to have potentially low concentrations of latex-specific IgE antibodies, as there appears to be a finite possibility for these assays to misclassify sera as being positive or negative for latex-specific IgE antibodies. Published in 1999 by John Wiley & Sons, Ltd.
THE EFFECT OF THERMAL BURNS ON THE THYROID ACTIVITY OF THE RAT1

DECREASED thyroid activity, measured as I131 uptake, has been reported following the administration of various stressing agents such as vaccines (Williams, 1949), epinephrine (Soffer, 1949, 1950), chemical agents (Paschkis, 1950), anoxia and abnormal nutritional states (Van Middlesworth, 1950), ACTH and cortisone (Money, 1950; Reiss, 1950) and early stages of infection with Lieshmania (Stauber and Mauer, 1952). Botkin and Jensen (1952) have shown an early decrease in I131 uptake by the thyroid following treatment with epinephrine and thyrotropin. Increased I131 uptake following the stress of X-irradiation has been observed by Botkin et al., (1952); whereas, the findings of Bogoroch (1951) indicated that during various types of acute stress I131 uptake by rat thyroid is consistently less than that of normal rats. Studies by Gribble and Peters (1951) suggest that burning may stimulate thyroid activity, but the investigations of Sellers (1950) and You (1950) indicate no changes in thyroid activity following ...
Thermal studies of some divalent metal chelates of croconic acid

The thermal properties of chelates of croconic acid and squaric acid with divalent copper, cobalt, nickel and zinc have been investigated by TG and DTA. The decreasing order of thermal stability for the decomposition of the croconate chelates was Ni > > Zn > Co=Cu and for the squarate complexes, Zn > Co=Cu > Ni. The copper croconate TG showed water loss in two distinct steps. This was rationalized on the basis of the already known Jahn-Teller effect for this molecule. The nickel squarate was thought to have a different structure than the other squarate chelates. Activation energies were calculated for the croconate chelates from their DTA curves.
Scaling, light-cone expansion, and the Van Hove model

Author(s): Bander, M | Abstract: With certain assumptions on the coupling of two currents to particles of increasing spin, it is shown that the Van Hove model results in Bjorken scaling and Regge asymptotic behavior. The fields corresponding to these particles are related to the products appearing in the operator-product expansion near the light cone. © 1971 The American Physical Society.
Evaluating and reporting astigmatism for individual and aggregate data

Abstract Purpose: To demonstrate the proper method for evaluating and reporting astigmatism for individual and aggregate data. Setting: University of Texas Medical School and Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA. Methods: The surgically induced refractive change (SIRC) was determined for three data sets of patients who have had keratorefractive (photorefractive keratectomy) or cataract surgery. To make changes in refraction comparable, vertex distances for the refractions and keratometric index of refraction were considered. Doubledangle plots and single-angle plots were then used to display the data. Polar values (cylinder and axis) were converted to a Cartesian (x and y) coordinate system to determine the mean value of the induced astigmatism for each data set. Results: Doubled-angle plots clearly demonstrated the trends of induced astigmatism for each data set, and the mean value for induced astigmatism agreed exactly with the intuitive appearance of the plot. Conclusions: Converting astigmatism data to a Cartesian coordinate system allowed the correct computation of descriptive statistics such as mean values, standard deviations, and correlation coefficients. Using doubled-angle plots to display the data provides the investigator with the best method of recognizing trends in the data.
Functional Homology of gHs and gLs from EBV-related γ-herpesviruses for EBV-induced Membrane Fusion

Epstein-Barr virus (EBV) is a human gamma-herpesvirus that primarily infects B lymphocytes and epithelial cells. Entry of EBV into B cells requires the viral glycoproteins gp42, gH/gL and gB, while gp42 is not necessary for infection of epithelial cells. In EBV, gH and gL form two distinct complexes, a bipartite complex that contains only gH and gL, used for infection of epithelial cells, and a tripartite complex that additionally includes gp42, used for infection of B cells. The gH/gL complex is conserved within the herpesvirus family, but its exact role in entry and mechanism of fusion is not yet known. To understand more about the functionality of EBVgH/gL, we investigated the functional homology of gHs and gLs from human herpesvirus 8 (HHV8) and two primate (rhesus and marmoset) gamma-herpesviruses in EBV-mediated virus-free cell fusion assay. Overall, gHs and gLs from the more homologous primate herpesviruses were better at complementing EBV gH and gL in fusion than HHV8 gH and gL. Interestingly, marmoset gH was able to complement fusion with epithelial cells, but not B cells. Further investigation of this led to the discovery that EBVgH is the binding partner of gp42 in the tripartite complex and the absence of fusion with B cells in the presence of marmoset gH/gL is due to its inability to bind gp42.
NMR relaxation of Spin

The mathematical expressions for interpreting the results of spin-lattice relaxation, transverse relaxation, spin-lattice relaxation in the rotating frame, and Ostroff–Waugh multiple-pulse sequence relaxation experiments on spin-3/2 nuclei with electric quadrupole interaction in an isotropic environment are biexponential. A protocol for applying these expressions to investigate quadrupole interactions and ionic motions in complex aqueous heterogeneous systems such as biopolymer gels and biological tissue is described. Experimental evidence for at least two different environments for hydrated sodium ions, including an isotropic liquid aqueous phase and an anisotropic interfacial phase at the macromolecules, is reviewed. The use of the basic equations and experimental protocol are illustrated for systems of increasing complexity, ranging from simple NaCl aqueous solutions, highly concentrated agarose gels, gelatin gels, and gellan gels to xanthan gels that contain ordered macromolecules. Many different experiments on various biopolymer samples indicate a correlation time of approximately 1 ns for ions at the interface that dominates in determining spin-lattice relaxation and also the long component of the transverse relaxation that arises from the central transitions. The transverse relaxation of the satellite transitions is dominated by much longer correlation times that may be related to the geometry of the macromolecular matrix in which the hydrated aqueous sodium ions diffuse. In the case of xanthan, the macromolecular ordering causes residual quadrupolar splitting and enables the measurement of several very long correlation times. One of these appears to agree with the Kuhn length of xanthan that was determined by light scattering experiments on dilute solutions. © 2001 John Wiley & Sons, Inc. Concepts Magn Reson 13: 294–325, 2001
Recurrent Pneumocystis carinii pneumonia following apparent recovery.

Recurrence of Pneumocystis carinii pneumonitis occurred in 2 children with acute lymphocytic leukemia approximately 7 months after recovery from the initial infections which had been treated with pentamidine isethionate. Both patients appeared free of pulmonary disease between the episodes of P. carinii pneumonitis. Serum immunoglobulin values were not significantly altered and both patients were in hematologic remission of leukemia. Reinfection or relapse of P. carinii pneumonitis has not been previously reported in children or adults following apparent recovery.
Living Cationic Polymerization of Olefins. How Did the Discovery Come About

The tortuous road to living carbocationic polymerizations is chronicled. The impetus for this project was my conviction that, just as living anionic polymerizations have started with a critical insight, a similar breakthrough will also be possible with cations. Upon retrospect, the facts show a three-step progression to the objective: Discovery of 1) controlled initiation, 2) reversible termination (quasiliving systems), and 3) controlled chain transfer. But what good is the discovery of a process without demonstrating its usefulness in terms of desirable products? Thus, a section concerns unique microarchitectures obtainable only by this technique: functional liquids, telechelics, thermoplastic elastomers, etc. The marketing of some of these products has already started, and the fundamental exploration of the promises of this technique is in progress worldwide. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2285–2293, 1999
A crystal chemical approach to the formulation of self-lubricating nanocomposite coatings

In recent years, design or formulation of superhard coatings with self-lubricating properties has become one of the hottest research topics in the field of tribological coatings. In particular, the production of new coating architectures based on nano-composite or -layered morphologies has become very popular, especially for dry machining or high-temperature sliding bearing applications. In such applications, these coatings can lead to the formation of self-lubricating tribofilms that reduce friction and wear. In this paper, a crystal chemical model is presented to account for the formation of such low-shear and hence low-friction tribofilms. In support of this model, recent experimental findings of various research groups are also provided. The major benefit of this model is that it may provide a scientific means to better design and formulate future tribological coatings that provide not only superior wear resistance but also sufficient lubricity during dry machining or sliding applications.
Changes in nuclear morphology associated with elevated DNA levels during gametogenesis in cyclopoid copepods with chromatin diminution

Abstract. Most species of freshwater cyclopoid copepods follow a conventional course of DNA replication during gametogenesis, but certain species regularly undergo chromatin diminution during early embryogenesis, a process that is accompanied by the exclusion of large amounts of heterochromatic DNA from progenitor somatic cells and selective retention of this DNA by primordial germ cells after their segregation from the soma. We have used scanning microdensitometry and image analysis cytometry of individual Feulgen-stained nuclei to determine the DNA levels of individual somatic cell nuclei, oocytes, spermatocytes, and sperm for seven species, including Acanthocyclops brevispinosus, Acanthocyclops vernalis, Ectocyclops phaleratus, Eucyclops agilis, Eucyclops ensifer, Macrocyclops albidus, and Thermocyclops decipiens. The oocyte nuclei of these species have twice the DNA content of their diploid somatic cell nuclei. In specimens of Cyclops strenuus, Mesocyclops edax, Mesocyclops longisetus, Mesocyclops longisetus curvatus, and Metacyclops mendocinus, marked increases in DNA levels were noted in both female and male germ cells before meiosis. The appearance of enlarged nuclei with densely stained chromocenters is a distinguishing feature of oocytes and spermatocytes of cyclopoid species that exhibit excessive accumulations of DNA during gametogenesis and subsequently undergo chromatin diminution. The net increase in DNA content of the prediminution nuclei is 6–10 times the DNA level of their somatic cell nuclei and is largely attributable to increases in the amount of DNA associated with their heterochromatic chromocenters. The identification of a morphologically distinctive type of germ cell and its dramatic accumulation of large amounts of DNA before meiosis are discussed in terms of the selective elimination of heterochromatin during early cleavage stages in these cyclopoid species.
An approximation algorithm for a symmetric Generalized Multiple Depot, Multiple Travelling Salesman Problem

In this paper, we present an algorithm with an approximation factor of 2 for a Generalized, Multiple Depot, Multiple Travelling Salesman Problem (GMTSP) when the costs are symmetric and satisfy the triangle inequality. The algorithm requires finding a degree constrained minimum spanning tree which we compute using a Lagrangian relaxation.
Sequential Activation of Store-Operated Currents In Human Gingival Keratinocytes

Calcium ion store-activated currents in undifferentiated human gingival keratinocytes were measured with the whole cell patch clamp and fura techniques. Thapsigargin or intracellular inositol 1,4,5-trisphosphate and BAPTA rapidly induced an early transient current with ICRAC (calcium release activated calcium ion current) characteristics, and several later, larger sustained currents that depended on the mode of store depletion. Thapsigargin activated two currents within minutes of ICRAC activation. The first was a nonspecific cation current, INSC. A second conducted Na+ and Cs+, and was partially inhibited by thapsigargin (INa1). Dialysis with inositol 1,4,5-trisphosphate and BAPTA induced a later current that also conducted Na+ and Cs+, but was inhibited by extracellular calcium ion (INa2), with properties consistent with an epithelial Na+ channel current in some cells, and a calcium ion-insensitive Na+ current (INa3). Comparison of thapsigargin-evoked current changes with fura-2/AM results from separate cells indicated that both the ICRAC and the later, larger calcium ion conducting currents contributed to changes in intracellular calcium ion concentration, and likely play important parts in calcium ion signaling in undifferentiated keratinocytes.
Inelastic Electron Tunneling Spectroscopy

Inelastic electron tunneling spectroscopy is a useful technique for the study of vibrational modes of molecules adsorbed on the surface of oxide layers in a metal-insulator-metal tunnel junction. The technique involves studying the effects of adsorbed molecules on the tunneling spectrum of such junctions. The data give useful information about the structure, bonding, and orientation of adsorbed molecules. One of the major advantages of inelastic electron tunneling spectroscopy is its sensitivity. It is capable of detecting on the order of 10 to the 10th molecules (a fraction of a monolayer) on a 1 sq mm junction. It has been successfully used in studies of catalysis, biology, trace impurity detection, and electronic excitations. Because of its high sensitivity, this technique shows great promise in the area of solid-state electronic chemical sensing.
Inhibiting glycolysis to reduce seizures: how it might work

An inhibitor of glycolysis is shown to have antiepileptic effects in the rat kindling model, possibly through NADH-dependent regulation of gene expression. This may explain how the 'ketogenic diet' treatment works.
DNA repair mechanism by photolyase: electron transfer path from the photolyase catalytic cofactor FADH(-) to DNA thymine dimer.

Photolyase is an enzyme that catalyses photorepair of thymine dimers in UV damaged DNA by electron transfer reaction. The structure of the photolyase/DNA complex is unknown at present. Using crystal structure coordinates of the substrate-free enzyme from E. coli, we have recently built a computer molecular model of a thymine dimer docked to photolyase catalytic site and studied molecular dynamics of the system. In this paper, we present analysis of the electronic coupling and electron transfer pathway between the catalytic cofactor FADH(-) and the pyrimidine dimer by the method of interatomic tunneling currents. Electronic structure is treated in the extended Huckel approximation. The root mean square transfer matrix element is about 6 cm(-1), which is consistent with the experimentally determined rate of transfer. We find that electron transfer mechanism responsible for the repair utilizes an unusual folded conformation of FADH(-) in photolyases, in which the isoalloxazine ring of the flavin and the adenine are in close proximity, and the peculiar features of the docked orientation of the dimer. The tunneling currents show explicitly that despite of the close proximity between the donor and acceptor complexes, the electron transfer mechanism between the flavin and the thymine bases is not direct, but indirect, with the adenine acting as an intermediate. These calculations confirm the previously made conclusion based on an indirect evidence for such mechanism.
Direct correlation between creep compliance and deformation in entangled and sparsely crosslinked microtubule networks

The microtubule cytoskeleton is essential in maintaining the shape, strength and organization of cells and its misregulation has been implicated in neurological disorders and cancers. To better understand the structure-mechanics relationships in microtubule networks, we measure the time- and force-dependent viscoelastic responses of entangled and sparsely crosslinked microtubule networks to precise microscale manipulation. We use magnetic tweezers devices to apply calibrated step stresses and measure the resultant strain as a function of time. At short times the material behaves as an elastic solid. The linear regime is large, with gentle stiffening observed in entangled networks above ∼70% strains. Crosslinked networks are stiffer, and show an extended linear regime. At longer times, we find a creeping regime, suggesting that structural rearrangements of the network dominate the mechanical response. To understand the molecular origins of this behaviour, we use a newly-developed portable magnetic tweezers device to observe the network morphology using a confocal microscope while simultaneously applying point-like stresses to embedded magnetic particles. We observe substantial network compression in front of the bead with no evidence of long-length scale filament flow, and find that the spatial extent of the deformation field depends sensitively on network architecture and connectivity. Our results are important to understanding the role of the cytoskeleton in regulating cargo transportin vivo, as well as the basic physics of non-affine deformations in rigid rod polymer networks.
Elevated Incidence of Dental Caries in a Mouse Model of Cystic Fibrosis

Background Dental caries is the single most prevalent and costly infectious disease worldwide, affecting more than 90% of the population in the U.S. The development of dental cavities requires the colonization of the tooth surface by acid-producing bacteria, such as Streptococcus mutans. Saliva bicarbonate constitutes the main buffering system which neutralizes the pH fall generated by the plaque bacteria during sugar metabolism. We found that the saliva pH is severely decreased in a mouse model of cystic fibrosis disease (CF). Given the close relationship between pH and caries development, we hypothesized that caries incidence might be elevated in the mouse CF model. Methodology/Principal Findings We induced carious lesions in CF and wildtype mice by infecting their oral cavity with S. mutans, a well-studied cariogenic bacterium. After infection, the mice were fed a high-sucrose diet for 5 weeks (diet 2000). The mice were then euthanized and their jaws removed for caries scoring and bacterial counting. A dramatic increase in caries and severity of lesions scores were apparent in CF mice compared to their wildtype littermates. The elevated incidence of carious lesions correlated with a striking increase in the S. mutans viable population in dental plaque (20-fold increase in CF vs. wildtype mice; p value<0.003; t test). We also found that the pilocarpine-stimulated saliva bicarbonate concentration was significantly reduced in CF mice (16±2 mM vs. 31±2 mM, CF and wildtype mice, respectively; p value<0.01; t test). Conclusions/Significance Considering that bicarbonate is the most important pH buffering system in saliva, and the adherence and survival of aciduric bacteria such as S. mutans are enhanced at low pH values, we speculate that the decrease in the bicarbonate content and pH buffering of the saliva is at least partially responsible for the increased severity of lesions observed in the CF mouse.
Visualization of Larval Segmental Nerves in 3rd Instar Drosophila Larval Preparations

Drosophila melanogaster is emerging as a powerful model system for studying the development and function of the nervous system, particularly because of its convenient genetics and fully sequenced genome. Additionally, the larval nervous system is an ideal model system to study mechanisms of axonal transport as the larval segmental nerves contain bundles of axons with their cell bodies located within the brain and their nerve terminals ending along the length of the body. Here we describe the procedure for visualization of synaptic vesicle proteins within larval segmental nerves. If done correctly, all components of the nervous system, along with associated tissues such as muscles and NMJs, remain intact, undamaged, and ready to be visualized. 3rd instar larvae carrying various mutations are dissected, fixed, incubated with synaptic vesicle antibodies, visualized and compared to wild type larvae. This procedure can be adapted for several different synaptic or neuronal antibodies and changes in the distribution of a variety of proteins can be easily observed within larval segmental nerves.
Association of host cell surface adhesion receptors and other membrane proteins with HIV and SIV

We have developed a MAb-based capture assay to study the association of host cell membrane proteins with HIV and SIV. Class I and II MHC proteins were found to be associated with HIV as previously described. In addition to these molecules a number of other host molecules were found to be acquired by HIV, including CD71, CD63, CD43, and CD8. We have demonstrated that the major leukocyte adhesion receptors LFA-1 (CD11A/CD18) and CD44 are also associated with HIV. The level of surface expression of host membrane proteins did not predict relative expression (capture efficiency) of the virus. The use of virus-susceptible indicator cells showed that the assay involved host membrane protein-mediated capture of infectious HIV and SIV particles. Our data indicate that HIV and SIV acquire a number of host membrane proteins including adhesion receptors and that this process may be nonrandom. The acquisition of host cell adhesion receptors by HIV and SIV could have profound effects on the biology of the viruses, incl...
Architecture-driven software mobility in support of QoS requirements

Over the past decade researchers have shown that software architecture provides an appropriate level of granularity for assessing a system's Quality of Service (QoS) properties (e.g., latency). Similarly, many previous works have adopted an architecture-centric approach to reason about the runtime adaptation, including component mobility, of software systems. However, the relationship between software architecture, QoS, and mobility is not clearly understood. In this paper, we present a framework that takes an explicit software architecture perspective for assessing the system's QoS properties, and improving it through architectural mobility. We describe the implementation of the framework, as well as some of the remaining challenges that frame our ongoing work.
Transport through mixed proton, oxygen ion and electron/hole conductors: Analysis of fuel cells and electrolyzer cells using Onsager equations

Abstract Steady state transport through mixed proton, oxygen ion and electron/hole conductors is examined in fuel cell, driven fuel cell, and electrolyzer modes. Oxygen ion and proton current densities and the corresponding effective permeation fluxes of H2 and O2 obey Onsager equations. Chemical potentials of electrically neutral species, μ H 2 and μ O 2 in the electrolyte are determined in terms of transport parameters and operating conditions. In fuel cell mode μ H 2 and μ O 2 in the electrolyte are bounded by electrode values. However, in electrolyzer and driven fuel cell modes, μ H 2 and μ O 2 in the electrolyte need not be bounded by electrode values. Under some conditions μ H 2 and μ O 2 in the electrolyte exceed electrolyte thermodynamic stability leading to device failure. The analysis shows that from the standpoint of stability, electrolytes exhibiting mixed ionic-electronic conducting properties with large interfacial electron transfer resistances are preferred over predominantly ionic conducting materials.
Factors Controlling the Spectroscopic Properties and Supramolecular Chemistry of an Electron Deficient 5,5-Dimethylphlorin Architecture

A new 5,5-dimethylphlorin derivative (3H(PhlCF3)) was prepared and studied through a combination of redox, photophysical, and computational experiments. The phlorin macrocycle is significantly distorted from planarity compared to more traditional tetrapyrrole architectures and displays solvatochroism in the soret region of the UV–vis spectrum (∼370–420 nm). DFT calculations indicate that this solvatochromic behavior stems from the polarized nature of the frontier orbital (LUMO+1) that is most heavily involved in these transitions. Compound 3H(PhlCF3) also displays an intriguing supramolecular chemistry with certain anions; this phlorin can cooperatively hydrogen-bond two equivalents of fluoride to form 3H(PhlCF3)·2F– but does not bind larger halides such as Cl– or Br–. Analogous studies revealed that the phlorin can hydrogen-bond with carboxylate anions such as acetate to form 1:1 complexes such as 3H(PhlCF3)·OAc–. These supramolecular assemblies are robust and form even in relatively polar solvents such ...
Impacts of wildfire on the composition and structure of riparian forests in Southern California.

In southern California, wildfire is a ubiquitous agent shaping plant communities. Although fire impacts have been widely studied in chaparral-covered uplands, few data are available regarding fire and riparian vegetation. This study provides an example of the impact of a severe fire on riparian habitat. Plant species found in southern California gallery forests are typically adapted to maintaining populations following flood disturbances; we seek to determine whether structural and compositional changes following fire here demonstrate a similar quasi-equilibrium response. We sampled 65 quadrats on 11 transects along two streams in the Los Padres National Forest to characterize tree species size–class distributions before and after the 2002 Wolf Fire. We tested whether species exhibited differential patterns of survivorship and regeneration following the fire, and also tested for spatial variability in mortality within the floodplain. Alnus rhombifolia dominated the pre-fire forest, but experienced severe mortality in the fire and showed very limited resprouting after 3 years. Other prominent taxa (Populus, Salix, Quercus spp.) also lost considerable standing basal area, but had substantially greater rates of resprouting, resulting in a dramatically altered post-fire vegetation composition and structure. Fire impacts did not vary with landform position, leading to a distinctive homogenizing disturbance that contrasts with the spatially zoned and relatively stabilizing compositional influence that flood events have in this same riparian setting.
Age of the Fjord Stade moraines in the Disko Bugt region, western Greenland, and the 9.3 and 8.2 ka cooling events

Abstract Retreat of the western Greenland Ice Sheet during the early Holocene was interrupted by deposition of the Fjord Stade moraine system. The Fjord Stade moraine system spans several hundred kilometers of western Greenland's ice-free fringe and represents an important period in the western Greenland Ice Sheet's deglaciation history, but the origin and timing of moraine deposition remain uncertain. Here, we combine new and previously published 10 Be and 14 C ages from Disko Bugt, western Greenland to constrain the timing of Fjord Stade moraine deposition at two locations ∼60 km apart. At Jakobshavn Isfjord, the northern of two study sites, we show that Jakobshavn Isbrae advanced to deposit moraines ca 9.2 and 8.2–8.0 ka. In southeastern Disko Bugt, the ice sheet deposited moraines ca 9.4–9.0 and 8.5–8.1 ka. Our ice-margin chronology indicates that the Greenland Ice Sheet in two distant regions responded in unison to early Holocene abrupt cooling 9.3 and 8.2 ka, as recorded in central Greenland ice cores. Although the timing of Fjord Stade moraine deposition was synchronous in Jakobshavn Isfjord and southeastern Disko Bugt, within uncertainties, we suggest that Jakobshavn Isbrae advanced while the southeastern Disko Bugt ice margin experienced stillstands during the 9.3 and 8.2 ka events based on regional geomorphology and the distribution of 10 Be ages at each location. The contrasting style of ice-margin response was likely regulated by site-specific ice-flow characteristics. Jakobshavn Isbrae's high ice flux results in an amplified ice-margin response to a climate perturbation, both warming and cooling, whereas the comparatively low-flux sector of the ice sheet in southeastern Disko Bugt experiences a more subdued response to climate perturbations. Our chronology indicates that the western Greenland Ice Sheet advanced and retreated in concert with early Holocene temperature variations, and the 9.3 and 8.2 ka events, although brief, were of sufficient duration to elicit a significant response of the western Greenland Ice Sheet.
Whole insect and mammalian embryo imaging with confocal microscopy : Morphology and apoptosis

Background: After fluorochromes are incorporated into cells, tissues, and organisms, confocal microscopy can be used to observe three-dimensional structures. LysoTracker Red (LT) is a paraformaldehyde fixable probe that concentrates into acidic compartments of cells and indicates regions of high lysosomal activity and phagocytosis, which both correlate to apoptosis activity. LT has been shown to be an indicator of apoptotic cell death which is correlated to other standard apoptotic assays. Methods: The mammalian samples were stained with LT, fixed with paraformaldehyde/glutaraldehyde, dehydrated with methanol (MEOH), and cleared with benzyl alcohol/benzyl benzoate (BABB). Following this treatment, the tissues were nearly transparent. Mosquitoes were fixed with MEOH and stained with propidium iodide. Next the tissues were dehydrated with MEOH and cleared with BABB. Results: Tissues as thick as 500 μm can be visualized after clearing with BABB. LT staining revealed apoptotic regions in mammalian limbs, fetuses, and embryos. Morphological observation of insect tissue consisted of combining autofluorescence with either nucleic acid staining (either propidium iodide or ethidium bromide). Conclusions: The use of BABB matches the RI of the tissue within the suspending medium. It helps in increasing the penetration of laser light in a confocal microscope by reducing the amount of light scattering artifacts and allows for the visualization of morphology in thick tissues. LT is a probe that stains the acid regions of tissues and cells and has been correlated to apoptosis. Morphological features of a tissue or organism (embryo, mosquito larvae) can be elucidated by fixation aldehydes, autofluorescence, and red-emitting probes. This sample preparation procedure with optimization of confocal laser scanning microscopy allowed for the detection and visualization of apoptosis in fetal limbs and embryos which were ∼500-μm thick. © 2006 International Society for Analytical Cytology
Design of experiments for parameter estimation in multiresponse situations

Abstract : A criterion is developed for the choice of n experimental runs in multiresponse situations, after N runs are already available. The criterion is applied to three examples involving two particular non-linear multiple response models and the results are discussed.
Variation in Water Quality and Phytoplankton Nutritional Status in an Urbanized Lake System (Lake Merced, California, USA)

Abstract Lake chemistry is influenced by land use in the surrounding watershed, particularly in complex urban landscapes, which are commonly subjected to an increase in material loadings. Because land use is rarely uniform, individual ecosystems embedded within the landscape may reflect varying water quality conditions. The Lake Merced system is composed of three lake basins with watersheds (surface area = 13 km2) residing entirely within the city of San Francisco, California. On nine occasions from January-June 1995 we sampled the two main lakes (North and South Lake Merced) within the system to evaluate their relative productivity and nutrient status. On each date, several physical-chemical conditions were measured, and nutrient enrichment bioassays were performed to evaluate the nutritional status of the phytoplankton (nitrogen (N) and phosphorus (P) enrichment in a 2 × 2 factorial experimental design). All the parameters tested except temperature were higher in the north lake compared with the south (...
The status of Lake Lanao endemic cyprinids (Puntius species) and their conservation

The endemic cyprinid species flock of Lake Lanao, Philippines is a classic example of explosive evolution. Based on historical surveys, most of the 18 endemic cyprinid species in Lake Lanao are now believed to be extinct. We compared results of landing and market surveys conducted in 2008 to information from historical surveys. Field sampling and fishermen interviews provided additional information on the status of the endemic and other fish species in Lake Lanao. Puntius lindog and Puntius tumba were the only two endemic species recorded in 2008, accounting for 0.01 % and 0.04 % respectively of the total weight harvested. Our discovery that at least two endemic cyprinids remain in Lake Lanao is surprising and significant as the lake is increasingly imperiled by human disturbances, exploitation and introduced species. Protecting and conserving the remaining endemic species are important management priorities.
Selectively bred Wistar–Kyoto rats: an animal model of depression and hyper-responsiveness to antidepressants

The Wistar-Kyoto (WKY) rat strain demonstrates endogenous hormonal and behavioral abnormalities that emulate many of those found in symptom-presenting depressive patients. Evidence suggests that the WKY strain may harbor heterogeneity not found in other inbred strains, including greater behavioral and genetic variability. We took advantage of this variability and selectively bred WKY for 'depressive' behavior using immobility in the forced swim test (FST) as a functional selector. Successive generations of selective breeding resulted in rats that exhibited the extremes of immobility in the FST: 'WKY most immobile' (WMI) and 'WKY least immobile' (WLI). Male WMI rats also showed significantly decreased activity in the open field test (OFT). Plasma corticosterone (CORT) response to restraint stress was significantly lower and less variable in WMI compared to WLI males. Subacute treatment of males with several classes of antidepressant had different effects on FST behavior in the two substrains. Both desipramine (10 mg/kg body weight), a tricyclic antidepressant, and phenelzine (7.5 mg/kg), a monoamine oxidase inhibitor, significantly and drastically decreased FST immobility in WMI. In contrast, WLI showed a limited response to these antidepressants. Neither substrain responded to fluoxetine (10 mg/kg), a selective serotonin reuptake inhibitor. These data show that selective breeding of WKY rats has resulted in two substrains with reduced variability and differing responsiveness to antidepressants, which represent a novel means to dissect the molecular mechanisms underlying depressive behavior.
A Novel Family of Phosphole-Thiophene Oligomers for Optoelectronic Applications

A 2-terthienylphospholide can be prepared from a 1-terthienylphosphole by reaction with tBuOK in diglyme at 150 °C. This phospholide is then transformed into the corresponding 1-methyl-2-terthienylphosphole-borane. This borane complex fluoresces at 510 nm in CH2Cl2 with a quantum yield of 0.17. The excited-state displays a significant charge transfer between the terthienyl substituent and the phosphole ring as shown by the shift of the emission to lower energies upon increasing the polarity of the solvent.
Theory of Flicker and Transient Responses, I. Uniform Fields*

Photopic flicker data are explained in terms of a theoretical model of two retinal processes. The first is a linear diffusion process (presumably in the receptors), with a large dynamic range (∼105). The second is a nonlinear inhibiting network (neural feedback at the synapses of the plexiform layers) that adaptively controls the sensitivity and time constants of the model. The magnitude of its transfer function fits the flicker data quantitatively at all frequencies, over a wide range of adaptation levels. The corresponding small-signal impulse responses are also calculated: their latencies and leading edges (associated with receptor activity) are invariant with adaptation level; the remaining phases of these transient waveforms (associated with the graded potentials of secondary neurons) adapt strongly, in accord with current histology and micro-electrode findings.
Self-aligned resist patterning with 172nm and 193nm backside flood exposure on attenuated phase shift masks

We have investigated self-aligned resist patterning for a patterning accuracy of photo mask. Self-aligned resist pattern can be formed by backside flood exposure on photo-mask. It had been already proved by the experiments with 248 nm light source exposure on binary (Cr on Quartz) and KrF attenuated phase shift masks. Attenuated phase shift masks are generally composed of Cr/MoSiN/Quartz, MoSiN/Quartz, and Quartz layers. MoSiN layers of attenuated phase shift mask have the optical property of 6% transmittance at 248 nm light source, and the interference of the 6%- transmitted light makes the undesirable resist pattern profile on MoSiN-Quartz boundary. This paper shows the fresh possibility of the self-aligned resist pattern fabrication on attenuated phase shift masks using backside flood exposure. To solve the optical property of MoSiN layer, self-aligned resist patterns of KrF attenuated phase shift mask was fabricated using 193 nm wavelength backside flood exposure and ArF attenuated phase shift mask used 172 nm wavelength. The shorter wavelength than generally applied wavelength could minimize transmittance on MoSiN area. Besides we used Negative PR to make the self-aligned resist pattern on exposed regions. These experimental concepts help to form the selective PR patterning on only quartz regions of attenuated phase shift mask.
Amino Acids in Raisins

The amino acid profile of raisins indicated that of the 2.9g amino acids per 100g dry matter of raisins, arginine was present in the greatest concentration (25%), followed by proline and glutamic acid.