cssi/SciSciGPT-SciSciNet huggingface dataset:
Multi-Color, Live Super-Resolution Microscopy Reveals the Timescale and Potential of Mean Force for Co-Clustering Between the B cell Receptor and Lyn Kinase

The super-resolution techniques STORM and PALM allow the nanometer scale localization of fluorescent probes in both live and fixed cells. In fixed cells, robust quantification of interactions between proteins is accomplished by cross correlating the reconstructed images of spectrally separated probes. Here, we extend this technique to live cells using simultaneous STORM and PALM measurements quantified using time resolved cross correlation with 20μs temporal resolution. We demonstrate that the potential of mean force between two labeled proteins can be determined even when objects have significant diffusion. We apply this technique to the activation of B cell receptor (BCR) and investigate the timescale and magnitude of co-clustering between the BCR and the Src kinase Lyn. We simultaneously compare quantitative measurements of receptor clustering, receptor-Lyn co-clustering, and protein mobility. We find that Lyn is recruited to BCR clusters with a potential of mean force greater than 1kT after stimulation with multivalent antigen, concurrent with BCR self-clustering and slowdown. We correlate two distinct lipid modified PALM probes with the B cell receptor in live cells. A saturated lipid moiety is recruited to BCR clusters with a potential of mean force of greater than 0.5kT, while a branched and unsaturated lipid moiety is not recruited to BCR clusters. These observations confirm that BCR clustering leads to the formation of a stable lipid domain enriched in saturated components, in quantitative agreement with our observations in chemically fixed cells. In ongoing work, we are using these experimental and analytical methods to quantify how lipids mediate interactions between proteins involved in early stages of BCR cell signaling.
Effect of external potassium on the coupled sodium: Potassium transport ratio of axons

1. Resting membrane potential and the current-voltage relation were measured in crayfish giant axons bathed in various potassium solutions with and without ouabain. 2. Ouabain caused a depolarization of the membrane at each [K] o used but did not affect membrane resistance. 3. The ouabain-sensitive transport current was least (3 μA/cm2) in 0 mM [K] o and greatest (7 μA/cm2) in 16.2 and 21.6 mM [K] o . 4. The assumption was made and some indirect evidence presented that axons equilibrated in various potassium solutions maintain constant internal sodium and potassium concentrations for up to 3 h. 5. On the basis of this assumption, the apparent ratio of coupled Na∶K transport was calculated. It was found to be least (−1.3/l) in 0 mM [K] o and to approach infinity in 16.2 and 21.6 mM [K] o . 6. The data indicate that the apparent variability of the Na∶K exchange ratio likely represents an intrinsic property of the exchange mechanism and is less likely to be explained by a fixed-ratio coupled Na∶K transport operating in parallel with electro-neutral Na∶Na or K∶K exchange.
Effect on intraocular pressure of extraocular muscle surgery for thyroid-associated ophthalmopathy

Purpose To study the effect of extraocular muscle surgery on intraocular pressure (IOP) in patients with thyroid-associated ophthalmopathy. Design Retrospective, observational case series. Methods The medical records of patients with restrictive myopathy secondary to thyroid-associated ophthalmopathy who underwent strabismus surgery from July 1, 1997 through July 31, 2003 were reviewed and analyzed retrospectively. Seventeen patients met the criteria and were included in this study. All patients were seen at the Thyroid Eye Center at the University of California, San Diego, a university-based tertiary referral center. The main outcome measure was IOP readings obtained before and after surgery in both primary gaze and upgaze. Results A statistically significant decrease in IOP in upgaze was noted after extraocular muscle recession. The mean IOP before surgery was 16.6 ± 3.78 mm Hg in primary gaze and 23.2 ± 7.27 mm Hg in upgaze. After strabismus surgery, the mean IOP after one month was 15.7 ± 2.36 mm Hg ( P = .215) in primary gaze and 18.9 ± 2.96 mm Hg in upgaze ( P = .001). Conclusions Strabismus surgery resulted in a significant reduction in IOP in the early postoperative period in patients with restrictive myopathy secondary to thyroid-associated ophthalmopathy.
Probability density function estimation of laser light scintillation via Bayesian mixtures

A method for probability density function (PDF) estimation using Bayesian mixtures of weighted gamma distributions, called the Dirichlet process gamma mixture model (DP-GaMM), is presented and applied to the analysis of a laser beam in turbulence. The problem is cast in a Bayesian setting, with the mixture model itself treated as random process. A stick-breaking interpretation of the Dirichlet process is employed as the prior distribution over the random mixture model. The number and underlying parameters of the gamma distribution mixture components as well as the associated mixture weights are learned directly from the data during model inference. A hybrid Metropolis–Hastings and Gibbs sampling parameter inference algorithm is developed and presented in its entirety. Results on several sets of controlled data are shown, and comparisons of PDF estimation fidelity are conducted with favorable results.
The unique and immunoglobulin-like regions of surrogate light chain component λ5 differentially interrogate immunoglobulin heavy-chain structure

Abstract PreBCR signaling is critical for B cell development and normally depends on the association of a nascent, component Ig H chain with the surrogate L chain (SLC), which helps ensure that only B cells that synthesize structurally sound antibody can develop. How the invariant and λ-like SLC vets billions of unique V H domains for compatibility with polymorphic κ and λ L chains is unclear, because the SLC is composed of not only the Ig domains of VpreB and λ5, but also the unique regions (URs) that reside at what would be the L chain CDR3. We evaluated the contribution of the Ig and UR domains of λ5 to H chain screening by evaluating the preBCR-forming capability of λ5 mutants with a diverse panel of H chains. Using transformed mouse B cells, we demonstrate that the Ig domain of λ5 was sufficient and its UR dispensable for the rejection of V H Q52 and V H 10 SLC-incompatible H chains. In contrast, the λ5 UR was necessary to discriminate between SLC-incompatible and -compatible V H 81X H chains. Substituting the Ig domains of λ5 with equivalent κ sequences impaired the SLC's ability to escort all H chains to the surface. Two SLC-incompatible H chains were able to form surface BCRs with two κ L chains, indicating that the SLC's ability to predict the L chain compatibility of a H chain is not absolute. In sum, λ5 differentially relies on the λ-like Ig and UR to probe H chain structure to best accommodate diversity among H chains.
Proteogenomic and functional analysis of chromate reduction in Acidiphilium cryptum JF-5, an Fe(III)-respiring acidophile

Acidiphilium cryptum JF-5, an acidophilic iron-respiring Alphaproteobacterium, has the ability to reduce chromate under aerobic and anaerobic conditions, making it an intriguing and useful model organism for the study of extremophilic bacteria in bioremediation applications. Genome sequence annotation suggested two potential mechanisms of Cr(VI) reduction, namely, a number of c-type cytochromes, and a predicted NADPH-dependent Cr(VI) reductase. In laboratory studies using pure cultures of JF-5, an NADPH-dependent chromate reductase activity was detected primarily in soluble protein fractions, and a periplasmic c-type cytochrome (ApcA) was also present, representing two potential means of Cr(VI) reduction. Upon further examination, it was determined that the NADPH-dependent activity was not specific for Cr(VI), and the predicted proteins were not detected in Cr(VI)-grown cultures. Proteomic data did show measureable amounts of ApcA in cells grown with Cr(VI). Purified ApcA is reducible by menadiol, and in turn can reduce Cr(VI), suggesting a means to obtain electrons from the respiratory chain and divert them to Cr(VI). Electrochemical measurements confirm that Cr reduction by ApcA is pH dependent, with low pH being favored. Homology modeling of ApcA and comparison to a known Cr(VI)-reducing c-type cytochrome structure revealed basic amino acids which could interact with chromate ion. From these studies, it can be concluded that A. cryptum has the physiologic and genomic capability to reduce Cr(VI) to the less toxic Cr(III). However, the expected chromate reductase mechanism may not be the primary means of Cr(VI) reduction in this organism.
Rac signaling in tumorigenesis and as target for anticancer drug development

Rac GTPases are crucial signaling regulators in eukaryotic cells, acting downstream of many cell surface receptors. They play essential roles in diverse cellular functions including cytoskeleton dynamics, cell motility, cell survival and apoptosis. Their activities are controlled by a tightly regulated GDP/GTP cycle coupled with an alternation between cytoplasm and membrane compartments. Aberrant Rac signaling is found in some human cancers as a result of changes in the GTPase itself or in its regulation loops. This review highlights recent findings regarding the molecular and functional aspects of Rac that mediate tumorigenic transformation and metastasis. It also describes the cellular mechanisms that potentially explain the complex role of Rac in tumorigenesis. Finally, it discusses approaches for modulating Rac function as a potential anticancer strategy.
Repetition blindness and illusory conjunctions: errors in binding visual types with visual tokens

Repetition blindness (Kanwisher, 1986, 1987) has been defined as the failure to detect or recall repetitions of words presented in rapid serial visual presentation (RSVP). The experiments presented here suggest that repetition blindness (RB) is a more general visual phenomenon, and examine its relationship to feature integration theory (Treisman & Gelade, 1980). Experiment 1 shows RB for letters distributed through space, time, or both. Experiment 2 demonstrates RB for repeated colors in RSVP lists. In Experiments 3 and 4, RB was found for repeated letters and colors in spatial arrays. Experiment 5 provides evidence that the mental representations of discrete objects (called "visual tokens" here) that are necessary to detect visual repetitions (Kanwisher, 1987) are the same as the "object files" (Kahneman & Treisman, 1984) in which visual features are conjoined. In Experiment 6, repetition blindness for the second occurrence of a repeated letter resulted only when the first occurrence was attended to. The overall results suggest that a general dissociation between types and tokens in visual information processing can account for both repetition blindness and illusory conjunctions.
A study of the effect of PP‐g‐MA and SEBS‐g‐MA on the mechanical and morphological properties of polypropylene/nylon 6 blends

The mechanical and morphological properties of polypropylene/nylon 6 blends compatibilized with PP grafted with maleic anhydride (PP-g-MA) and styrene/ ethene-co-butene/styrene grafted with maleic anhydride (SEBS-g-MA) are studied using a special version of a factorial design known as extreme vertices. Properties examined include yield stress, modulus, elongation, toughness, impact strength and morphology. Comparisons are made between various treatment combinations (i.e. a variety of blends) and polypropylene homopolymer using various statistical methods including analysis of variance (ANOVA), Scheffe's Test and Duncan's Multiple Range Test. Significant differences were found for yield stress, modulus, elongation, toughness and impact strength for specific treatment combinations versus PP as well as on average. Ternary diagrams are used to plot response surfaces of the measured data illustrating the main effects and interactions involved, while allowing correlations to be made with blend morphology. Indications from test results and analysis of response surfaces show a strong relationship between nylon/compatibilizer ratio and mechanical properties.
PNEUMATIC BARRIERS FOR OIL CONTAINMENT UNDER WIND, WAVE, AND CURRENT CONDITIONS

ABSTRACT An experimental laboratory study of the pneumatic barrier has recently been completed at Texas ?&M University (sponsored by the U S. Coast Guard). Both the fluid mechanics of air-bubble generated currents and their effectiveness for containing oil under wind, wave, and current loadings were investigated. The bubble-generated current has been found to provide an effective means of containing oil on water. However, under strong currents (2 knots) or breaking wave conditions, large quantities of air are required and the substantial increase in power requirements which results may prove the system uneconomical for some applications. Consequently, use of the pneumatic barrier to prevent oil spreading on water is recommended for protected areas with low (below 1.0 knot) currents.
A direct and precise method for the determination of serum globulins

Abstract The described method provides a simple and direct procedure for the quantitative determination of serum globulins. The procedure is based upon photometric quantitation of a colored derivative formed when the tryptophan present in globulin combines with p -dimethylaminobenzaldehyde. The test results based upon the determination of tryptophan are proportional to the globulin content, with only small interferences from albumin (bovine and human). These results correlate well with other acceptable test procedures without the necessity of interference compensation. The method should have wide application in both the human and veterinary medical fields, because of its easy adaptability to automation in the clinical laboratory, and because of the ease with which the manual method may be performed in the clinician's office.
The inverse resonance problem for CMV operators

We consider the class of CMV operators with super-exponentially decaying Verblunsky coefficients. For these we define the concept of a resonance. Then we prove the existence of Jost solutions and a uniqueness theorem for the inverse resonance problem: given the location of all resonances, taking multiplicities into account, the Verblunsky coefficients are uniquely determined.
Nonantigenicity and immunologic tolerance, the role of the carrier in the induction of tolerance to the hapten.

Treatment of adult mice with dinitrophenyl (DNP) bound to isogeneic serum resulted in a specific inability to respond to DNP after challenge with DNP-keyhole limpet hemocyanin (KLH) in complete Freund's adjuvant. The unresponsiveness to the hapten had all the characteristics of immunologic tolerance: it had a definite induction time; it was transient but could be maintained by additional injections of the tolerogen; it was antigen specific and dose dependent. In addition, the induction of tolerance to DNP is dependent on the nature of the carrier. Two main conclusions can be drawn from these data: DNP conjugates of three homopolymers of lysine were found to be nonimmunogenic in mice, yet tolerogenic. Thus, antigenicity is not necessary to induce tolerance. Among the various carriers tested, isogeneic 7S immunoglobulin (IgG) was found to be the most effective to induce and maintain tolerance to the hapten. This suggests that IgG may have a function other than its usual role as an immunoglobulin.
REAGINIC ACTIVITY ASSOCIATED WITH IGG IMMUNOGLOBULIN

Five human sera with reaginic activity to a number of allergens were fractionated using anion exchange chromatography. In each serum, fractions which contained detectable IgG and no detectable IgA had capacity to fix to skin and subsequently elicit a P-K reaction. Four of these sera had reaginic activity about equally distributed between fractions containing only IgG and fractions containing mixtures of IgG and IgA. A fifth serum contained reaginic activity to crystalline bovine serum albumin (BSA) and most of the activity was associated with the fraction which contained only IgG. This serum was extensively studied using a variety of techniques and it was confirmed that most of the reagin to BSA in this serum was in those fractions containing only IgG. Since reaginic activity can no longer be considered a unique property of IgA the implications of finding antibody with reaginic qualities in immunoglobulins other than IgA are discussed.
The influence of black race and socioeconomic status on the use of breast‐conserving surgery for medicare beneficiaries

BACKGROUND This study explores the influence of socioeconomic status (SES) and black race on the use of breast-conserving surgery (BCS) as opposed to mastectomy for early stage breast carcinoma. METHODS A cohort of 41,937 female Medicare inpatients age 65-79 years who had undergone BCS or mastectomy treatment in 1990 for local or regional breast carcinoma was studied. SES was estimated based on the patients' zip code of residence. RESULTS Greater use of BCS was associated with higher income and increased education as determined by the patients' zip code area (P < 0.001 for each), and with lower vacant housing rates and fewer persons living below the poverty line in the patients' zip code area (P < 0.001 for each). Black women were less likely than women of other races to undergo BCS (odds ratio, 0.80; 95% confidence interval, 0.71-0.91). However, in a multivariate regression model adjusting for stage and urban versus rural residence, income, educational status, and poverty rate remained significant predictors of patient receipt of BCS, whereas black race did not remain an independent predictor of this treatment. CONCLUSIONS Women residing in higher SES areas are more likely to undergo BCS. The reduced use of BCS in black women appears attributable to SES. Cancer 1997; 79:314-9. © 1997 American Cancer Society.
A study of oak-pollen production and phenology in northern California: prediction of annual variation in pollen counts based on geographic and meterologic factors.

To assess the characteristics of oak-pollen production and dispersal, 9 years of weekly volumetric air sampling, with modified swing-shield rotoslide pollen samplers, were obtained in San Francisco and San Jose, Calif. The Mediterranean climate of coastal California supports 9 million acres of oaks of nine different species. The major pollen contributors in the two sampling areas are coast live oak ( Quercus agrifolia Nee) and valley oak ( Quercus lobata nee). Sampling data indicate that grains may be wind transported at least 16 km (10 miles). A strong correlation exists between pollen capture and total rainfall a full year before pollen release. The correlation is statistically significant, based on a Spearman rank test. A positive regression line slope demonstrates that the greater the precipitation, the stronger the stimulus for pollen production. The median count can be predicted within a factor of two with high probability a full year before release. During most seasons, the peak pollen collection from coast live oak and valley oak occurs in early April. A second peak production period, in mid-May, represents the conglomerate of other oak-pollen types. However, there are major yearly differences in the relative amounts of pollen released during these two periods. Consequently, individual oak pollinosis may depend as much on variable production by the major species as on the total quantity of airborne oak pollen. These data will help clinicians predict and prepare for the intensity of the oak-pollen season and explain seasonal variations in clinical symptoms from year to year. The question of cross-reacting and specific allergens among oak species can be answered by RAST-inhibition studies. Although clinical and immunologic research on ragweed pollinosis has been invaluable as a model for other pollens, this study indicates that aerobiologic and immunologic investigation of other allergenic pollens is essential for proper diagnosis and treatment in practice.
Nutrient Management Practices Used in Potato Production In Idaho

Sound nutrient-management practices are an essential component of modern intensive potato (Solanum tuberosum) production systems. Economic and environmental issues are requiring Idaho potato producers to use management practices that are effective and efficient to remain competitive in the market. Identical potato production management surveys were conducted in 1997 and again in 2006–2007 to determine current nutrient management practices used by Idaho potato growers. This Dillman mail-based survey collected data that were used to determine current nutrient-management strategies and changes that have occurred over the past 10 years. In 2006–2007, more than 77% of growers used preplant soil tests for determining nitrogen (N) application needs. More than 96% of potato growers relied on petiole analysis of potato plant tissue for N management during the growing season. Changes have occurred in only 7 of 28 nutrient-management categories evaluated in the past 10 years, indicating maturity rather than evolutio...
Reliability characteristics of high- k dielectrics

Abstract In this paper, recent results of Weibull slopes, area scaling factors, and breakdown behaviors observed for both soft breakdown and hard breakdown are discussed. These results would help to shed light on the breakdown mechanism of HfO 2 gate dielectrics. The Weibull slope β of the hard breakdown for both the area dependence and the time-to-dielectric-breakdown distribution was found to be β =2, whereas that of the soft breakdown was about 1.4 (EOT=14 A). We also integrated the time-to-breakdown characteristics of HfO 2 under unipolar AC voltage stress on MOS capacitors. The results show that longer lifetime of HfO 2 has been observed when compared to constant voltage stress. Higher frequency and lower duty cycle in the AC stress resulted in longer lifetime. As thickness decreases, the amount of lifetime enhancement decreases. The enhancement of unipolar t BD is attributed to less charge trapping during the “on time”, t on and charge detrapping during the off time, t off . It is proposed that time ( τ in ) for charge to be trapped in HfO 2 is longer than t on of unipolar stress under high frequency. In addition to experimental results, possible solutions are discussed.
Differential effects of magnesium on tubulin-nucleotide interactions

Abstract Magnesium-depleted 2-( N -morpholino)ethanesulfonate (Mes), glutamate, tubulin and microtubule-associated proteins were prepared and used to study the effects of exogenously added MgCl 2 on tubulin-nucleotide interactions in 0.1 M Mes with microtubule-associated proteins and in 1.0 M glutamate. Endogenous levels of Mg 2+ in the systems studied were approximately stoichiometric with the tubulin concentrations and largely derived from the tubulin. We examined the effects of added Mg 2+ on tubulin polymerization, GDP inhibition of polymerization, binding of GDP and GTP to tubulin, and GTP hydrolysis. Exogenously added Mg 2+ had markedly different effects on these reactions. The order of their sensitivity for a requirement for added Mg 2+ was as follows: GTP binding > GTP hydrolysis > polymerization > GDP binding. Inhibition of polymerization by GDP varied inversely with the Mg 2+ concentration and was greatest in the absence of the cation. These results indicate that GDP and GDP-Mg 2+ interact with similar affinity at the exchangeable site, while GTP-Mg 2+ has a higher affinity for tubulin than does free GTP. Nevertheless, under appropriate conditions, free GTP can interact sufficiently well with tubulin to permit both nucleation and elongation reactions.
The structure of porcine protegrin genes

We cloned the genes of three protegrins, a family of cathelin-associated antimicrobial peptides originally isolated from porcine leukocytes. Each gene comprised 4 exons and 3 introns, wherein Exon I encoded the signal sequence and the first 37 amino acids of cathelin, Exons II and III contained 36 and 24 additional cathelin residues and Exon IV contained the final two cathelin residues followed by the protegrin sequence. This quadripartite gene structure helps explain how structurally diverse antimicrobial peptides can be expressed on common, cathelin-containing precursors. Southern blot probed with an oligonucleotide specific for protegrin genes suggested that several identical or nearly identical protegrin genes were densely clustered in the pig chromosome.
CONDUCTIVITY AND TRANSPORT IN NEON DEUTERIUM DISCHARGES IN THE PLT TOKAMAK.

Introduction of large amounts of neon into Ohmically heated deuterium discharges in the PLT tokamakl results in higher central electron temperature (Te(0) 3 keV) and values of electron energy containment time that are larger than in regular discharges at the same electron density (τEe = 44 ms at e = 2 × 1019 m−3). For steady-state discharges with high effective Z (~ 5–8) the conductance is larger than that predicted by neoclassical theory by as much as a factor of two. Transport rates of hydrogen-like and helium-like ions can be fairly well approximated by assuming a diffusion constant of between 0.4 and 1 m2s−1. Within experimental uncertainties the diffusion of hydrogen-like neon is the same for co- and counter-directed high-power neutral beams.
Measuring depressive life experiences

Abstract During recent years psychologists have begun to investigate the variety of stressful life events that trigger distress. The present research extended this stress-distress model to the study of depressive life experiences through the development and validation of the Depressive Life Experiences Scale (DLES). The DLES is an objective self-report instrument designed to assess six depressogenic life experiences: (1) social exits, (2) interpersonal disharmony, (3) personal inertia, (4) personal frustrations, (5) personal inadequacies, and (6) others' misfortunes. Reliability analyses provided evidence for the internal consistency of the items on the six DLES subscales, and other results revealed a gender distinct pattern of findings for several DLES subscales. In addition, five of the DLES subscales correlated positively with a measure of ‘negative’ life change, and predictive validity was demonstrated through a pattern of negative correlations between the DLES and several indices of life satisfaction. The importance of the Depressive Life Experiences Scale for the empirical and conceptual analysis of depression is discussed.
Supergravity and superstrings in (2 + 1) dimensions

We study n=1 supergravity written on a two-dimensional disc (× time) in the absence of any sources. The dynamics of the boundary of the disc is equivalent to that of a superstring in (2+1)-dimensional Minkowski space. The relevant current algebra for the theory corresponds to the central extension of the super-Poincare loop group. We find unitary representations of the current algebra by applying both a highest weight state construction and the method of induced representations.
AC Generating System for Executive Aircraft

This paper describes an ac generating system designed for a twin jet executive aircraft. The system employs two variable frequency 9/21 kva generators to supply power for aircraft surface heating, fuel pumps, trim motor, and instruments. The system is unique in private executive aircraft in that it is automatic and employs static circuitry for the control and the conversion of variable frequency power to 400 cps constant frequency voltage for aircraft instruments.
Laboratory transmission of dog heartworm (Dirofilaria immitis) by three species of mosquitoes (Diptera: Culicidae) from eastern Maryland, USA.

Three species of mosquitoes from eastern Maryland, USA, were tested for their ability to transmit Dirofilaria immitis (Leidy) from heartworm-positive dogs to recipient dogs with no prior exposure. Two recipient dogs and 1 uninfected control dog were allotted to each test species. Experimental mosquitoes were initially infected through feeding on a microfilaremic donor. Infection levels and larval development were observed by dissection. After a 3-wk incubation period, the mosquitoes were allowed to feed on recipient dogs. Both recipient and control dogs were tested for microfilariae during the months after exposure. Following a 6- to 10-month period, dogs were euthanized and examined for adult worms. Patent infections were produced in 4 dogs exposed to the bites of Aedes sollicitans or Aedes triseriatus, with average infection levels of 12.5 and 58 worms per dog, respectively. Patent infection was produced in 1 of the dogs exposed to the bites of Anopheles punctipennis. All controls were negative. All 3 test species were found to be capable of transmitting D. immitis to dogs. Under laboratory conditions, Ae. sollicitans and Ae. triseriatus were more successful at transmission than An. punctipennis.
Active circuit analysis

Modern circuit analysis programs (CAP) such as PSPICE and MICROCAP offer efficient and accurate alternatives to more traditional "paper and pencil techniques". Nevertheless, the ability to quickly analyze circuit behavior without the aid of a computer is an important skill that provides valuable insights into circuit performance. The "paper and pencil" technique presented is easy to learn, easy to use, and provides a rapid estimate of circuit behavior. >
Undergraduate education in power electronics

This paper addresses the issue of undergraduate education in the field of power electronics. Based on the 1990 survey conducted by the Power Engineering Education Resources Subcommittee, we carefully study the collected data to address key issues regarding undergraduate education in power electronics. Suggested curriculum in power electronics is presented. Moreover, state-of-the-art power electronics laboratory set-up along with supporting simulation laboratory is described. Simulation design examples using Pspice program for some power electronics projects are given.
Experimental Investigation of the Transition to Spatiotemporal Chaos with a System-Size Control Parameter

Using a localized laser-heating method to allow the use of system size as a control parameter, we experimentally investigate, using liquid-crystal electroconvection with soft boundary conditions, the onset of spatial temporal chaos (STC) with increasing system size. We find that temporal periodicity is significantly quenched as the system size increases. The increase of the fourth moment (kurtosis) of the temporal Fourier transform provides a very useful quantitative measure of the loss of temporal periodicity (hence the onset of STC) as the pattern size increases, and also provides a simple means for determining a natural chaotic length scale. This length scale is comparable to the length of vertical rows observed in the original pattern. Our experiments, thus, imply that there are well-defined building blocks, which in our case are easily visualized, that control the dynamics in STC liquid crystal convection. The results of our experiments appear to be consistent with the conclusions of recent STC computer simulations carried out by Fishman and Egolf.
Developments in behavioral finance and experimental economics and Post Keynesian finance theory

Keynes drew upon psychology in developing his economic theories, and researchers in behavioral finance have integrated psychology into the study of how investors make financial decisions. Another group of researchers, experimental economists, tested some remarks of Keynes on the psychology of economic actors in specifically designed experiments. Some research in these fields, however, has been misguided because of an inadequate understanding of Keynes's original insights. Researchers in these fields can benefit from comments by Post Keynesian economists. At the same time, they have a lot to offer Post Keynesians in developing a Post Keynesian theory of finance.
Number of fibres in the optic nerve and the number of ganglion cells in the retina of anurans.

USING a light microscope, Bruesh and Arey1 found that there were about 15,300 myelinated and 13,700 unmyelinated fibres in the optic nerve of the frog (Rana pipiens), and about 10,200 myelinated and 5,500 unmyelinated fibres in the optic nerve of the toad (Bufo americanus). However, in my electron microscope study of the optic nerve of these and other Anurans (Rana catesbeiana, Bufo terrestris and Hyla cinerea) I have found2 that the unmedullated axons are in a considerably larger number, having been underestimated by a factor of 30 or more, and that most of them could not have been resolved with the light microscope. My observations, though, do not greatly contradict the earlier numbers of myelinated fibres, for these can be counted with reasonable accuracy after myelin stain. In the present communication I only wish to report about the general arrangement of the unmyelinated axons and their number. The full description of the fine anatomy of the optic nerve is deferred to an extensive article now in preparation.
Multistage separation of metal ions with a series of composite supported liquid membranes

Abstract The possibility of performing multistage separations of metal cations, present at low concentrations in aqueous solutions, using a series of composite supported liquid membranes (SLM), interposed between compartments containing identical aqueous electrolyte solutions, is discussed. The multistage separation of Eu 3+ . from Am 3+ and of Sm 3+ from Nd 3+ and Ce 3+ is theoretically analyzed. A single separation stage, using a thin, three-layer asymmetrical composite SLM, which allows differential permeation of Eu 3+ . and Am 3+ , is described and experimentally studied. The composite SLM consists of a 1 mm thick aqueous slab sandwiched between acidic and neutral supported liquid membranes. The results demonstrate that the permeation of each cation through the thin composite SLM can be described by a single permeation parameter which is equal to the permeability coefficient through the first acidic supported liquid membrane of the composite layer.
Theory and Modeling of the Binding in Cationic Transition-Metal-Benzene Complexes

Binding energies are estimated for the complexes of benzene with the first-row transition-metal ions (M+ = Ti+−Cu+) via both kinetic modeling and quantum chemical simulation. A variational transition-state theory model implementing an ion−quadrupole plus ion-induced dipole potential is employed in the modeling of the kinetic data for the collision-induced dissociation of these complexes. For Cr+, a global potential is generated for its interaction with benzene and radiative association experiments are also modeled. Implementation of this potential in the transition-state analyses indicates only minor anharmonicity effects for the complex state density near the dissociation threshold and negligible deviation from the long-range potential-based predictions for the transition-state partition functions. Theoretical optimized geometries, binding energies, and vibrational frequencies are determined with the B3LYP (Becke-3 Lee−Yang−Parr) density functional. The V+, Ni+, and Fe+ complexes are found to have modest...
A mutation in the catalytic cistron of aspartate carbamoyltransferase affecting catalysis, regulatory response and holoenzyme assembly

We describe here a mutation in the gene encoding the catalytic subunit of aspartate carbamoyltransferase (ATCase, pyrB) which produces an enzyme retaining catalytic activity as holoenzyme (2C3:3R2) and catalytic trimer (C3) but which shows neither cooperative substrate kinetics nor nucleotide effector response. Furthermore, the holoenzyme assembly seems quite fragile in that the enzymatic activity is recovered only partially as holoenzyme following growth of Escherichia coli in the presence of zinc. In contrast, the enzyme from wild-type E. coli strain E63 is recovered almost entirely in its dodecameric form in identical conditions. The gene encoding the mutant pyrB was isolated from a λdargI+pyrB+ transducing phage (obtained from N. Glansdorff). This mutation differs from other previously reported mutations affecting the catalytic subunit1,2 in that significant catalytic activity is retained but homotropic and heterotropic communication is lost3.
Developing Metrics for Evolving a Musically Satisfying Result from a Population of Computer Generated Music Compositions

Creating a computational metric of the quality and musicality of a computer generated music composition is a challenging problem. This paper describes a possible way to develop numerically based metrics for standardizing the fitness evaluation of a population of computer generated music compositions. These metrics are based on assertions by music theorists about the dynamic forces within music that provides the music with a sense of motion and phrasing. The actions of several musical parameters are ranked according to the sense of intensity they produce. This process is applied to an acoustic music composition, and the values are then plotted on a graph. The composite curve from these values give the evaluator a sense of the patterns of lower and higher degrees of intensity, thus providing a sense of how well the music provides a sense of motion and phrasing
Synergistic Inhibitor Binding to the Papain‐Like Protease of Human SARS Coronavirus: Mechanistic and Inhibitor Design Implications

We previously developed two potent chemical classes that inhibit the essential papain-like protease (PLpro) of severe acute respiratory syndrome coronavirus. In this study, we applied a novel approach to identify small fragments that act synergistically with these inhibitors. A fragment library was screened in combination with four previously developed lead inhibitors by fluorescence-based enzymatic assays. Several fragment compounds synergistically enhanced the inhibitory activity of the lead inhibitors by approximately an order of magnitude. Surface plasmon resonance measurements showed that three fragments bind specifically to the PLpro enzyme. Mode of inhibition, computational solvent mapping, and molecular docking studies suggest that these fragments bind adjacent to the binding site of the lead inhibitors and further stabilize the inhibitor-bound state. We propose potential next-generation compounds based on a computational fragment-merging approach. This approach provides an alternative strategy for lead optimization for cases in which direct co-crystallization is difficult.
Thermal resistance of salmonellae in egg yolk products containing sugar or salt.

Abstract THE addition of sugar or salt to a medium has an influence on the heat resistance of bacteria. Hansen and Riemann (1963), in reviewing factors affecting the heat resistance of nonsporing organisms, mentioned that salt exerts a protective action against heat. Such action was dependent on the kind of salt, the concentration, the suspending media used, and the test organisms. They further noted that high concentrations of soluble carbohydrate result in increased heat resistance of yeasts and bacteria. Stumbo (1963) reported that heat resistance of many organisms was increased progressively by salt concentrations up to four percent. Above four percent the heat resistance tended to decrease. High sugar concentrations tended to increase resistance. Cotterill and Glauert (1967) previously reported that the addition of sugar or salt increased the temperatures required to destroy Salmonella oranienburg in egg yolk. Salted egg yolk required a much higher temperature than sugared egg yolk. Frazier…
Influence of felodipine and verapamil on the sympathetic transmitter release and on the pre- and post-junctional effects of exogenous noradrenaline in the perfused rat kidney.

The effects of various concentrations (0.01 to 10 µmol/L) of felodipine and verapamil on the peripheral sympathetic function were studied in perfused rat kidney preparations in vitro. Neither of these agents inhibited stimulus-induced 3H- noradrenaline (norepinephrine) release (at 0.5 and 2.0Hz). Higher concentrations of felodipine (10 µmol/L) and verapamil (1 and 10 µmol/L) significantly potentiated the transmitter release at both frequencies of stimulation. Unlike phenotolamine, felodipine 10 µmol/L enhanced the ability of exogenous noradrenaline to inhibit 3H- noradrenaline-release, indicating that this vasodilator did not antagonise prejunctional α2- receptors. The effects of verapamil 1 µmol/ L were similar to that of felodipine in this respect; however, verapamil in higher concentrations (JO µmol/L) produced slight but significant attenuation of exogenous nor adrenaline-induced inhibition of the transmitter release. Both felodipine and verapamil produced concentration-dependent inhibition of the vasoconstrictor responses to exogenous noradrenaline. It is concluded from these studies that the effects of these agents on the transmitter release may not have any clinical significance, but their ability to attenuate vascular effects of noradrenaline could contribute to their antihypertensive properties.
Lack of effect of dibromochloropropane on the mouse testis

A single intraperitoneal injection of (101 x C3Hf)F male mice with 110 mg/kg of 1,2-dibromo-3-chloropropane (DBCP) showed no effect on spermatogonial stem cells or on differentiating spermatogonia as measured by cell counts made 3, 5, and 8 days after injection.
Statistical design for sampling and analysis of animal populations for chemical contamination

A strategy for sampling of animal tissues and a statistical approach for analyzing data on body burdens of a parent chemical and its metabolites is presented such that the data may be evaluated in relation to the detection limit(s) of the analytical techniques used and the criterion levels established for acceptable tissue concentrations.
A model for estimating airline passenger trip reliability metrics from system-wide flight simulations

Analysis of the benefits of government modernization initiatives for airports or air traffic control are conducted using complex software models that simulate up to 60,000 flights per day. These flight-centric simulations do not model passenger flows and therefore do not account for passenger trip delays due to cancelled flights and missed connections, which account for up to 60% of the total passenger trip delays. This paper describes a closed-form model for estimating passenger trip reliability metrics from flight delay data from system-wide simulations. The outputs of the model, (i) percent passengers disrupted, (ii) average passenger trip delay, and (iii) total passenger trip delays, are derived from the probability of delayed flights and network structure parameters. The model highlights the role of network structure, in addition to flight on-time performance, on passenger trip reliability. These results have implications for government and industry initiatives to improve flight on-time performance through modernization, consumer protection, and the conduct of benefits analysis.
Microdialysis Sampling Techniques Applied to Studies of the Foreign Body Reaction

Implanted materials including drug delivery devices and chemical sensors undergo what is termed the foreign body reaction (FBR). Depending on the device and its intended application, the FBR can have differing consequences. An extensive scientific research effort has been devoted to elucidating the cellular and molecular mechanisms that drive the FBR. Important, yet relatively unexplored, research includes the localized tissue biochemistry and the chemical signaling events that occur throughout the FBR. This review provides an overview of the mechanisms of the FBR, describes how the FBR affects different implanted devices, and illustrates the role that microdialysis sampling can play in further elucidating the chemical communication processes that drive FBR outcomes.
Hyperprolactinemia is not associated with hyperestrogenism in noncycling African elephants (Loxodonta africana)

African elephants in US zoos are not reproducing at replacement levels. This is in part due to physiological problems, one of which is abnormal ovarian cyclicity that has been linked to increased prolactin secretion (hyperprolactinemia). A relationship between increased estrogen production (hyperestrogenism) and hyperprolactinemia has been found in other species. Therefore, the objective of this study was to determine if elevated prolactin was associated with increased estrogen concentrations in non-cycling African elephants. In cycling elephants (n=12), prolactin secretion followed a normal cyclic pattern, with higher concentrations observed during the follicular phase; overall mean concentration was ∼18ng/ml and baseline prolactin was ∼6ng/ml. Non-cycling females (n=18) were categorized into three groups: (1) low prolactin ( 31ng/ml; n=8). Mean urinary estrogen conjugate concentrations ranged from 5.4 to 41.4ng/mg Crt, and were similar between normal cycling (15.4±1.5ng/mg Crt) and non-cycling, low prolactin elephants (18.4±7.3ng/mg Crt), but were lower in moderate (9.4±1.3ng/mg Crt) and marked hyperprolactinemic (9.8±1.1ng/mg Crt) groups (P<0.05). In conclusion, African elephants appear to be sensitive to alterations in prolactin production, with both low (e.g., a non-cycling pattern) and high prolactin secretion being associated with abnormal ovarian activity. However, hyperestrogenism was not related to hyperprolactinemia in the non-cycling females.
Spatio-temporal drought forecasting within Bayesian networks

Summary Spatial variations of future droughts across the Gunnison River Basin in CO, USA, are evaluated in this study, using a recently developed probabilistic forecast model. The Standardized Runoff Index (SRI) is employed to analyze drought status across the spatial extent of the basin. The runoff generated at each spatial unit of the basin is estimated by a distributed-parameter and physically-based hydrologic model. Using the historical runoff at each spatial unit, a statistical forecast model is developed within Bayesian networks. The forecast model applies a family of multivariate distribution functions to forecast future drought conditions given the drought status in the past. Given the runoff in the past (January–June), the forecast model is applied in estimating the runoff across the basin in the forecast period (July–December). The main advantage of the forecast model is its probabilistic features in analyzing future droughts. It develops conditional probabilities of a given forecast variable, and returns the highest probable forecast along with an assessment of the uncertainty around that value. Bayesian networks can also estimate the probability of future droughts with different severities, given the drought status of the predictor period. Moreover, the model can be used to generate maps showing the runoff variation over the basin with the particular chance of occurrence in the future. Our results indicate that the statistical method applied in this study is a useful procedure in probabilistic forecast of future droughts given the spatio-temporal characteristics of droughts in the past. The techniques presented in this manuscript are suitable for probabilistic drought forecasting and have potential to improve drought characterization in different applications.
ACTIONS OF CAROTENOIDS IN BIOLOGICAL SYSTEMS

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 561 CAROTENOID FUNCTIONS . . . . . . . . . .. . .. . . .. . .. . ... . . . .. . . .. 564 CAROTENOID ACTIONS .. . .. . .. . .. . . . . . .. . . . . ......... . ... . 564 In vitro Antioxidant Actions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 564 In vivo Antioxidant Actions 571 Antimutagenesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 573 Protection Against Genotoxicity and Malignant Transformation . . . . . . . . . . . . 573 Anticarcinogenesis . . .. . . . . .. . . . . . . . .. . ... . .. . ... .. . .. . ... 575 CAROTENOID ASSOCIATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 580 FUTURE CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 580