cssi/SciSciGPT-SciSciNet huggingface dataset:
Diurnal stratification, photosynthesis and nitrogenfixation in a shallow, equatorial Lake (Lake George, Uganda)

Summary From a series of experiments and measurements covering one 24-h period in Lake George the diurnal patterns of photosynthesis, nitrogen-fixation and stratification are described. The thermal cycle shows three distinct phases of isothermy, intense stratification and mixing. During stratification the surface water temperature reached 36°C, whereas the bottom temperature remained at 25°C. The phytoplankton are evenly distributed at dawn, sink out during the day and tend towards an even redistribution as thermal stratification breaks down. Depth-time profiles of oxygen concentration and pH values showed that intense photosynthetic and respiratory activity occurred. The shortness of the predominant limnological cycle is thought to be instrumental in restricting species fluctuations. Changes of total CO2 concentration in situ within the euphotic zone indicated that 2.25 g C/m2.12 h were photosynthetically fixed during daytime. From changes of in situ oxygen concentration, gross photosynthesis was estimated to be 12 g O2/m2.12 h and net particulate production over 24 h as zero. Photosynthetic activity was also measured with the i^C and oxygen techniques by enclosing algal samples in light and dark bottles. The patterns of activity recorded by the two methods were similar, although quantitatively the oxygen method gave rather higher values than did the method. Daily gross photosynthesis was estimated as 15.56 g O2/m2.12 h and 4.5 gC/m2.12 h. These figures are compatible with one another and with the production estimates calculated from Tailing's model of integral daily photosynthesis. The balance between respiration and photosynthesis is described as a function of the underwater light climate and the relative rate of respiration. Both the experimental and theoretical approaches suggest that the column 24-h net particulate production is an extremely small percentage of gross photosynthesis. Nitrogen-fixation was measured using both the 15N2 and the acetylene reduction techniques. The day-long incubation of the 15N2 experiment showed that 11 mg N/m2.day were fixed. The series of shorter acetylene reduction experiments gave a value of 58 mg N/m2.day. The acetylene technique showed relatively high nitro-genase activity at very low light intensities. The 15N2 results indicated little N2-fixation at low light intensities. The differences between the two techniques are discussed. Gross photosynthesis estimates calculated from seven different methods run simultaneously are compared. The figures show reasonable agreement, but since the gaseous environment in the euphotic zone is particularly suitable for photo respiration the values are not considered reliable estimates of phytoplankton photosynthesis.
Precise simulated percentiles in a pinch

Abstract A percentile point simulation algorithm is presented. The algorithm is useful when computer storage and time considerations are at a premium. The algorithm employs various time- and storage-saving ideas, including a “pinching” mechanism that reduces the proportion of simulated values stored as the number of iterations is increased. Algorithm output includes a measure of precision as well as the simulated percentile point. The simulation can be stopped when the desired degree of precision has been attained.
Ion Electrodiffusion Governs Silk Electrogelation.

Silk electrogelation involves the transition of an aqueous silk fibroin solution to a gel state (E-gel) in the presence of an electric current. The process is based on local pH changes as a result of water electrolysis – generating H+ and OH− ions at the (+) and (−) electrodes, respectively. Silk fibroin has a pI = 4.2 and when local pH < pI, E-gel forms. An experimental system was constructed that allowed the measurement of E-gel growth and pH distribution for an applied current. To explain the observed rectangular pH profile of pHgel ≈ 4 surrounded by pHsilk-solution ≈ 10, a finite-element ion electrodiffusion model was developed. The model relies on electrodiffusion of the generated H+ and OH− ions. Initially, inputs into the model were the measured E-gel and voltage curves. The governing ion electrodiffusion equations were solved and the calculated pH matched the experimental pH profile, indicating that ion electrodiffusion dictates local pH changes and E-gel growth. Furthermore, the model predicted the constant currents (2 mA and 3 mA) necessary for two hypothetical E-gel growth curves and these results were then validated experimentally. The model thus shows how ion electrodiffusion governs the electrogelation process and also provides predictable outcomes for fundamental and practical E-gel applications.
A comparative analysis of pilin genes from pathogenic and nonpathogenic Neisseria species

Pathogenic Neisseria species elaborate type IV pili, which are considered important for virulence. In this study, we examined pilin-encoding expression loci (pilE) in nonpathogenic Neisseria species. PCR based screening detected homology to a conserved N-terminal region of pilE in 12 of 15 Neisseria species, including all human commensal isolates. The three species failing to display homology were isolated from nonhuman sources. We have also characterized complete pilE loci from the human commensal species N. lactamica and N. cinerea. As anticipated, the predicted protein sequences from these species display features typical of all type IV pilins. In addition, these commensal pilins possess two highly conserved regions, SV2 and CYS2, which are shared among all neisserial pilins. However, a comparative analysis of pilE loci from pathogenic and nonpathogenic Neisseria species reveals two distinct structural groups, one composed of the pilin genes from N. lactamica, N. cinerea, and the class II pilin-producing subset of N. meningitidis isolates, the other of gonococcal and meningococcal class I pilin-encoding genes. Since both class I and class II pilin-producing meningococci can act as pathogens, structural relationships among neisserial pilin genes do not obviously reflect either species membership or ability to cause human disease.
Distributed Graph Algorithmics: Theory and Practice

As a fundamental tool in modeling and analyzing social, and information networks, large-scale graph mining is an important component of any tool set for big data analysis. Processing graphs with hundreds of billions of edges is only possible via developing distributed algorithms under distributed graph mining frameworks such as MapReduce, Pregel, Gigraph, and alike. For these distributed algorithms to work well in practice, we need to take into account several metrics such as the number of rounds of computation and the communication complexity of each round. For example, given the popularity and ease-of-use of MapReduce framework, developing practical algorithms with good theoretical guarantees for basic graph algorithms is a problem of great importance.In this tutorial, we first discuss how to design and implement algorithms based on traditional MapReduce architecture. In this regard, we discuss various basic graph theoretic problems such as computing connected components, maximum matching, MST, counting triangle and overlapping or balanced clustering. We discuss a computation model for MapReduce and describe the sampling, filtering, local random walk, and core-set techniques to develop efficient algorithms in this framework. At the end, we explore the possibility of employing other distributed graph processing frameworks. In particular, we study the effect of augmenting MapReduce with a distributed hash table (DHT) service and also discuss the use of a new graph processing framework called ASYMP based on asynchronous message-passing method. In particular, we will show that using ASyMP, one can improve the CPU usage, and achieve significantly improved running time.
Factor Requirement of the Bacteriophage f2 Replicase

Escherichia coli cells infected with the RNA bacteriophage f2 contain a rifampicin-resistant poly C-dependent GTP-polymerizing activity not present in uninfected cells1. Extensive purification of the f2 poly G polymerase yields a complex containing the phage-coded replicase protein. Structurally, the f2 poly G polymerase appears to be very similar to the replicase of the distantly related bacteriophage Qβ1–3. Both enzymes contain three host-coded proteins in addition to the phage-specific replicase polypeptide. When the polypeptides of the purified f2 and Qβ enzymes are compared by Polyacrylamide gel electrophoresis in sodium dodecyl sulphate, a difference in electrophoretic mobility is detectable only for the respective phage-specified polypeptides1. Functionally, however, the Qβ and f2 enzymes differ significantly. The highly purified Qβ replicase is able to use Qβ complementary (minus) strands and several small RNAs, as well as cytidylate-containing synthetic polymers, as templates for nucleotide polymerization3–5. Additional bacterial protein factors must be present only for activity with Qβ viral (plus strand) RNA template4,5. The highly purified f 2 enzyme is active in the presence of poly C template, but is inactive with either f2 plus strand or f2 minus strand RNA template1. Template-specific f2 replicase activity is detectable in partially purified preparations of the f2 poly G polymerase1,6,7. Such preparations show a strong preference for f2 RNA among natural RNA templates and synthesize, in vitro, polynucleotides homologous to f2 RNAs. We show here that the functional difference between the f2 and Qβ enzymes is due to a differential factor requirement for replicase activity. The highly purified f2 poly G polymerase, unlike its Qβ counterpart, requires the presence of an easily dissociable factor for activity with f2 minus strand template, as well as with f2 plus strand template.
A model of debonding instability for solid propellant rocket motor: Part II — Unequal longitudinal and transverse stress rate

Abstract The interface between a soft and a hard material is vulnerable to debonding because of the prevailing high stress gradient that could be further aggravated under dynamic transient conditions. Such a situation is common in a solid-fuel rocket motor where unstable debonding could be triggered from the initiation of a macrocrack near the interface. The transition from a survival state to a failure state requires knowledge of how the nonlinear, dissipative and nonhomogeneous effects of the dissimilar material interface would interact with load. The solid-fuel rocket motor problem is modeled by a three-layered composite system made of steel, adhesive and rubber under plane extension. Assessed are the time dependent nonhomogeneous deformation and possible failure modes. Only initial properties of the materials were used to determine the evolution of nonequilibrium response. This is made possible by application of the isoenergy density theory that accounts for internal heat generation and energy dissipation effects. Results are presented in two parts. In Part 1, the applied stress rates are assumed to be 0.75 ksi/s in both the longitudinal and transverse direction while Part II assumes different stress rates in these two directions. At approximately one second after loading, a slanted but straight macrocrack of about 5 × 10−3 in. is predicted to occur in the rubber next to the interface. This initial crack was found to become unstable at eight seconds and was estimated to be close to the adhesive/rubber interface over a length of 1.88 in. The onset of fracture depended directly on the load transient behavior.
Ferrohydrodynamic torque-driven flows

Abstract Ferrofluid motion driven by a travelling wave magnetic field can be in the same or opposite direction to the direction of wave propagation. A net time average body force on a ferrofluid is produced when there is a time phase lag between the ferrofluid magnetization M and the driving magnetic field H. With M and H not collinear, there is also a dipole torque exerted on each magnetic domain which is balanced by the fluid viscous drag. Conservation of linear and angular momentum equations are solved in the steady state for a ferrofluid layer stressed by a travelling wave magnetic field. This configuration can be easily set up as an experiment, allows closed form solutions for the time average flow and spin fields, and exemplifies the essential physics of ferrohydrodynamic interactions.
Nonlinear atom optics of bosons and fermions

We review the general principles underlying the nonlinear atom optics of bosons and fermions. Examples such as matter-wave four-wave mixing and coherent matter-wave amplification are presented, and potential applications are discussed.
Seizure susceptibility of neuropeptide-Y null mutant mice in amygdala kindling and chemical-induced seizure models

Neuropeptide Y (NPY) administered exogenously is anticonvulsant, and, NPY null mutant mice are more susceptible to kainate-induced seizures. In order to better understand the potential role of NPY in epileptogenesis, the present studies investigated the development of amygdala kindling, post-kindling seizure thresholds, and anticonvulsant effects of carbamazepine and levetiracetam in 129S6/SvEv NPY(+/+) and NPY(-/-) mice. In addition, susceptibility to pilocarpine- and kainate-induced seizures was compared in NPY(+/+) and (-/-) mice. The rate of amygdala kindling development did not differ in the NPY(-/-) and NPY(+/+) mice either when kindling stimuli were presented once daily for at least 20 days, or, 12 times daily for 2 days. However, during kindling development, the NPY(-/-) mice had higher seizure severity scores and longer afterdischarge durations than the NPY(+/+) mice. Post-kindling, the NPY(-/-) mice had markedly lower afterdischarge thresholds and longer afterdischarge durations than NPY (+/+) mice. Carbamazepine and levetiracetam increased the seizure thresholds of both NPY (-/-) and (+/+) mice. In addition, NPY (-/-) mice had lower thresholds for both kainate- and pilocarpine-induced seizures. The present results in amygdala kindling and chemical seizure models suggest that NPY may play a more prominent role in determining seizure thresholds and severity of seizures than in events leading to epileptogenesis. In addition, a lack of NPY does not appear to confer drug-resistance in that carbamazepine and levetiracetam were anticonvulsant in both wild type (WT) and NPY null mutant mice.
Measurement of envelope thermal transmittances in multifamily buildings

Abstract One of the uncertainties in the energy balance of buildings is associated with the envelope thermal transmittance which, based on blueprints, can be determined from handbooks and engineering calculations. The calculated value is of questionable accuracy due to variable construction practices, uncertainties in material properties, and sometimes even different interpretations of the blueprints. Thermal bridges and multidimensional heat flows are usually unaccounted for and add to the uncertainty. Therefore, it is sometimes necessary to determine the thermal transmittance experimentally. Electric co-heating, i.e., the replacement of the heating system by electric heaters, is a known experimental procedure for the determination of the overall thermal transmittance (losiness) of single-family buildings. However, for multifamily buildings this procedure is impractical due to the buildings's size and complexity. Instead, an equivalent procedure is suggested which permits the determination of an effective envelope thermal transmittance. Its calculation is based on a steady-state heat balance, averaged over many days, for a sample apartment of the building. Since apartments in multifamily buildings are usually not well thermally isolated from each other, heat transfer between the sample apartment and its neighbors has to be accounted for. This is solved by measuring the temperatures in the neighboring apartments and calculating the respective heat flows. To minimize the error introduced by the uncertainty in such heat flows, the average temperature in the sample apartment is controlled, with electric heaters, to be at a temperature that will, at least nominally, cancel the heat flows from the neighboring spaces. The procedure was tested in an apartment of a 60-unit multifamily building.
Philosophy and Art: Changing Landscapes for Aesthetics

Part I of this essay will examine how the interplay between philosophy and art over the past century is reflected in the aesthetic theories of four leading Twentieth century aestheticians: Walter Benjamin, Merleau-Ponty, Gilles Deleuze, Arthur Danto. The philosophers’ theories are linked to the developments in art most directly related to their respective approaches to problems in aesthetics. Part II will explore selected non-philosophical social and technological developments that are in the process of altering the course of contemporary art today. Among these are globalization, the art market, social/political issues, popular culture, virtual reality, and new manifestations of the avant-garde. Key factors that warrant consideration for future developments in aesthetics are identified in the hope that today’s and future aestheticians will begin to consider what changes are required in aesthetics to address these new developments in art.
Independence of glucocorticosteroids and blood-brain barrier amino acid permeability

The effects of abnormal levels of circulating glucocorticosteroids upon the carrier-mediated transport of tyrosine and tryptophan across the blood-brain-carrier of the adult male rat were studied. The uptake of C14 labeled tyrosine or tryptophan was measured relative to that of simultaneously injected 3H2O, a freely diffusible internal standard. Fifteen sec after rapid intracarotid injection the rats were decapitated and brain tissue was homogenized and subjected to liquid scintillation counting. The level of circulating glucocorticosteroids was altered by intraperitoneal injection of cortisol (30 mg/kg) or corticosterone (30 mg/kg) 20 min prior to the amino acid injection. Rats were also injected with cortisol (10 mg/kg) or corticosterone (10 mg/kg) for 14 days. These rats were then injected with cortisol (10 mg/kg) or corticosterone (10 mg.kg) 90 min before the experiment. The amino acid uptake indices were analyzed statistically by the Wilcoxan Rank Sum Test. In no case was the uptake of tyrosine or tryptophan found to differ significantly (p <0·10) between the experimental and control rats. It is concluded that no correlation between levels of circulating adrenal glucocorticosteroids and transport across the blood brain barrier of the amino acid precursors of the putative neurotransmitters, norepinephrine and serotonin, can be demonstrated by this method.
Excited state relaxation in Cr(CN)6−n(H2O)nn−3 complexes

The emission spectra and excited state decay rates have been recorded for Cr(CN)6−n(H2O)nn−3 (n = 0-6) complexes. Both the transition energy and relaxation rates increase with n but the large changes in transition energies are not sufficient to account for the failure of the displaced coordinate to explain the relaxation rate results.
FINAL COMMENTS ON HUDESMAN, PAGE, AND RAUTIAINEN'S (1992) SUBLIMINAL PSYCHODYNAMIC ACTIVATION EXPERIMENT

Hudesman, et al.'s (1992) contention that their finding shows that subliminal psychodynamic activation (SPA) improved academic performance is questioned. That experiment lacked controls outlined by Fudin in 1986 which are needed to support the assumption that a positive SPA outcome is effected because the meaning of an entire experimental message is encoded. In 1993 Hudesman and Page argued that Gustafson and Kallmen's 1991 results, obtained with such controls, indicated that the controls do not have to be used in subsequent SPA experiments. The 1990 results of Greenberg and of Kothera, Fudin, and Nicastro, however, do not support those of Gustafson and Kallmen. From a different perspective, it is argued that good experimental controls are needed in all SPA experiments because they increase internal validity. Given that Hudesman, et al.'s subjects scored in a limited range on the mathematics portion of the 1978 CUNY Skills Assessment Test, the implication that their result can be generalized to all subjects is questioned.
Electrochemical desorption of self-assembled monolayers noninvasively releases patterned cells from geometrical confinements.

This report describes a method to pattern mammalian cells using self-assembled monolayers (SAMs), and then to use electrochemical desorption of these monolayers to release cells from their patterns. This method uses an oligo(ethyleneglycol)-terminated SAM to prevent,and a methyl-terminated SAM to allowadsorption of proteins and attachment of bovine capillary endothelial cells. Electrochemical removal of the oligo(ethyleneglycol)-terminated SAM allowed proteins to adsorb onto areas that had been previously inert and enabled cells to migrate into these areas. This straightforward technique is useful in bioassays for drug screening and for fundamental studies in cell biology.
Lags in vegetation response to greenhouse warming.

Fossil pollen in sediments documents vegetation responses to climatic changes in the past. Beech (Fagus grandifolia), with animal-dispersed seeds, moved across Lake Michigan or around its southern margin, becoming established in Wisconsin about 1000 years after populations were established in Michigan. Hemlock (Tsuga canadensis), with wind-dispersed seeds, colonized a 50,000 km2 area in northern Michigan between 6000 and 5000 years ago. These tree species extended ranges northward at average rates of 20–25 km per century. To track climatic changes in the future, caused by the greenhouse effect, however, their range limit would need to move northward 100 km per °C warming, or about 300 km per century, an order of magnitude faster than range extension in the past. Yet range extension in the future would be less efficient than in the past, because advance disjunct colonies have been extirpated by human disturbance, and because the seed source is reduced due to reductions in tree populations following logging. Many species of trees may not be able to disperse rapidly enough to track climate, and woodland herbs, which have less efficient seed dispersal mechanisms, may be in danger of extinction.
6300 Å quantum efficiency of the recombination mechanism in the night-time F layer

Simultaneous airglow and electron content measurements made at Hawaii are used to infer the number of 6300 and 6364 A quanta produced per electron lost in the nighttime F layer of the ionosphere. The equation of continuity of electrons is then solved numerically to obtain the electron density profile, and the amount of quenching is estimated. This leads to the number of excitations of O(super-1 D) per O2(+) recombination (epsilon). We find, for an exospheric temperature of 1100 K, epsilon is equal to 1.1 plus or minus 0.6, in good agreement with Zipf's laboratory measurement at 300 K.
Exploratory study on oxygen consumption on-kinetics during treadmill walking in women with systemic lupus erythematosus.

Abstract Keyser RE, Rus V, Mikdashi JA, Handwerger BS. Exploratory study on oxygen consumption on-kinetics during treadmill walking in women with systemic lupus erythematosus. Objective To determine whether oxygen consumption (V˙o 2 ) on-kinetics differed between groups of women with systemic lupus erythematosus (SLE) and sedentary but otherwise healthy controls. Design Exploratory case-control study. Setting Medical school exercise physiology laboratory. Participants Convenience samples of women with SLE (n=12) and sedentary but otherwise healthy controls (n=10). Intervention None. Main Outcome Measures V˙o 2 on-kinetics indices including time to steady state, rate constant, mean response time (MRT), transition constant, and oxygen deficit measured during bouts of treadmill walking at intensities of 3 and 5 metabolic equivalents (METs). Results Time to steady state and oxygen deficit were increased and rate constant was decreased in the women with SLE compared with controls. At the 5-MET energy demand, the transition constant was lower and MRT was longer in the women with SLE than in controls. For a similar relative energy expenditure that was slightly lower than the anaerobic threshold, the transition constant was higher in controls than in women with SLE. Conclusion V˙o 2 on-kinetics was prolonged in women with SLE. The prolongation was concomitant with an increase in oxygen deficit and may underlie performance fatigability in women with SLE.
Defining Gender Disparities in Pain Management

Background Prevalence rates of most musculoskeletal pain conditions are higher among women than men. Reasons for these prevalence disparities likely include sex differences in basic pain mechanisms and gender differences in psychosocial factors.
Electron Spin Resonance of a Center in Calcium Fluorophosphate

A spin-resonance center whose concentration is sensitive to x irradiation has been observed in synthetic calcium fluorophosphate crystals. It shows an electron spin of 1/2 and hyperfine interaction with two equivalent F/sup 13/ nuclei. Arguments are presented which lead to its identification as an O/sup -/ ion occupying an F/sup -/ site. (auth)
Fine structural lesions in the myocardium of a beer drinker with reversible heart failure

Abstract This report describes unusual pathologic changes detected by electron microscopic examination of a myocardial biopsy taken from a young beer drinker with reversible heart failure. The changes consisted of glycogen aggregates (alpha glycogen) in enlarged mitochondria and loss of contractile elements. It is not known whether these findings represent an unusual manifestation of alcoholic cardiomyopathy or a different and previously undescribed type of myocardial disease.
A kinetic study of pyrophosphate and peroxodiphosphate complexation of oxovanadium(IV) ion

The formation constant of the vanadyl pyrophosphate complex, VO(H_2P_2O_7), determined spectrophotometrically in acidic 1.0 M NaClO_4 solution, is logK = 4.4±0.1 at 25°C. The kinetics of the complexation of vanadyl ion by pyrophosphate and peroxodiphosphate were studied at pH 2.0 using stopped-flow spectrophotometry. The reactions are first-order in ligand and in vanadyl ion with rate constants k_2 = 2.3×10^4 and 7.5×10^3 M^(−1) sec^(−1) at 12°C for H_2P_2O_7^(2−) and H_2P_2O_8^(2−), respectively. The complexation reactions were followed by slower secondary processes which are attributed to polymerization. The results for the complexation reactions are consistent with an interchange mechanism for the formation of a monodentate complex, followed by rapid closure of the chelate ring. Peroxodisulfate, studied under similar conditions, showed no evidence of innersphere complexation.
Lactoferrin protects against concanavalin A-induced liver injury in mice.

Background: Liver diseases, caused by viral infection, autoimmune conditions, alcohol ingestion or the use of certain drugs, are a significant health issue, as many can develop into liver failure. Lactoferrin (Lac) is an iron-binding glycoprotein that belongs to the transferrin family. Owing to its multiple biological functions, Lac has been evaluated in a number of clinical trials to treat infections, inflammation and cancer. Aim: The present study aims to reveal a profound hepatoprotective effect of Lac, using a mouse model of Concanavalin A (Con A)-induced hepatitis, which mimics the pathophysiology of human viral and autoimmune hepatitis. Method: C57Bl/6J mice were injected with bovine Lac following Con A challenge. The effects of Lac on interferon (IFN)-γ and interleukin (IL)-4 expression were determined. The roles of Lac on T-cell apoptosis and activation, and leukocytes infiltration were examined. Result: The data demonstrated that the protective effect of Lac was attributed to its ability to inhibit T-cell activation and production of IFN-γ, as well as to suppress IL-4 production by hepatic natural killer T cells. Conclusion: These findings indicate a great therapeutic potential of Lac in treating in treating inflammatory hepatitis and possibly other inflammatory diseases.
A NEW VOLTZIALEAN CONE BEARING SEEDS WITH EMBRYOS FROM THE PERMIAN OF TEXAS

Description of the new cone is based on a single specimen from the Lower Permian Leonard Series of west Texas. The cone is 2.0 cm in diam. It has numerous fertile dwarf shoots subtended by ovate nonbifurcate bracts arranged in a compact spiral around the axis. The dwarf shoots are free from their subtending bracts and equal them in length. Each dwarf shoot is dorsiventrally flattened and bears about 30 sterile scales each of which is ovate and has a single vascular strand. These sterile scales are in spiral sequence but are lacking on the medial adaxial side of the dwarf shoot. A single flattened erect ovule is attached at the base on the adaxial side of the dwarf shoot and equals it in length. Tracheids and elongate parenchyma cells enclosed by the megaspore wall of one seed give evidence of the oldest embryos on record. Their occurrence in seeds that remain in the cone indicates that the kind of development in most modern plants, in which embryo growth precedes seed dispersal, had evolved by Lower Permian time. Moyliostrobus texanum gen. et sp. n. combines features typical of the Lebachia and Ernestiodendron types of cones.
Tactical reading: the ideology of form in David Antin's ‘Novel Poem’

Postmodern procedural poetry has received quite a bit of attention in the last several years. In her book Differentials: Poetry, Poetics, Pedagogy (2004), Marjorie Perloff devotes a chapter to the ...
Positive dependence in Markov chains

Abstract A general notion of positive dependence among successive observations in a finite-state stationary process is studied, with particular attention to the case of a stationary ergodic Markov chain. This dependence condition can be expressed as a positivity condition on the joint probability matrices of pairs of observations. Some useful conditions equivalent to positive dependence are obtained for reversible chains, but shown not to be equivalent for nonreversible chains.
Paclitaxel C-10 carbamates: Potential candidates for the treatment of neurodegenerative tauopathies

A series of paclitaxel C-10 carbamates was synthesized and evaluated in a bi-directional permeability assay in comparison with paclitaxel and the blood-brain barrier-permeable C-10 ester derivative, TX-67. A number of the carbamates were found not to be substrates for Pgp. Moreover, when tested for Pgp-inhibitory potential, representative compounds proved to be devoid of Pgp interactions. Side-by-side comparison between TX-67 and the corresponding C-10 carbamate, CNDR-3, revealed a significantly longer half-life for CNDR-3 in both mouse and human plasma, suggesting that this class of derivatives is appropriate for further in vivo evaluation.
Cold Urticaria: Inhibition of Cold-induced Histamine Release by Doxantrazole

Thirteen patients with cold urticaria were studied to assess the effect of the systemic drug doxantrazole, which has actions resembling disodium cromoglycate, on cold evoked histamine release. The patients, all of whom developed an immediate local whealing response after cooling of the forearm, demonstrated release of histamine into venous blood draining that forearm. Following doxantrazole treatment, significant suppression of histamine release occurred. In some but not all patients this was accompanied by diminution of urtication in response to cooling. A double-blind study was carried out in 3 subjects, all of whom showed diminished cold-stimulated histamine release after doxantrazole. Two of these showed clinical improvement. Doxantrazole had no effect on erythema due to intradermal histamine, but did suppress the erythematous reaction to intradermal injection of compound 48/80. Our results suggest that doxantrazole or related anti-allergic agents might be useful in the treatment of cold urticaria.
Broader perspective on the high-temperature superconduct- ing YBa2Cu3Oy system: The real role of the oxygen content.

A series of new $\mathrm{Y}{\mathrm{Ba}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{y}$-like materials are reported in which the oxygen content and the average [Cu-O] charge (or Cu valence) are separately varied over a wide range. We find a distinct boundary between samples showing anomalous insulating behavior and those with high ${T}_{c}$. These data are interpreted to demonstrate that the [Cu-O] charge in the sheets largely determines ${T}_{c}$ and that the variable oxygen content and the chains merely provide an insulating reservoir of charge.
Vulnerabilities of cognitive radio MAC protocols and countermeasures

Cognitive Radio (CR) is a promising technology for opportunistically accessing underutilized licensed spectrum to achieve higher spectrum efficiency and communication throughput. These performance gains are contingent upon the efficient coordination of channel access to the idle portion of the spectrum, an operation performed at the Medium Access Control (MAC) layer. In this article we identify various vulnerabilities of state-of-the-art CR MAC protocols, exploited by selfish/malicious CR users for gaining an unfair share of the available network resources. Furthermore, possible countermeasures for detecting and mitigating these vulnerabilities are discussed.
Experts warn against cutting NOAA Space Weather Center

A well-timed congressional hearing, coming in the midst of fierce geomagnetic storms, could help to restore funding to the U.S. National Oceanic and Atmospheric Administration's Space Environment Center (SEC). The center, which is the nation's official source of space weather alerts and warnings, currently is funded at $5.24 million for fiscal year 2003. That amount is $2 million less than it received the previous year. The Bush Administration has requested $8.02 million in funding. The appropriations bill, for the departments of Commerce, Justice, and State for fiscal year 2004, passed on 23 July by the House of Representatives, calls for funding the SEC at the $5.29 million level.
Arylpropane-1,3-diols in lignins from normal and CAD-deficient pines.

Significant quantities of arylpropane-1,3-diols have been identified in lignins isolated from a CAD-deficient pine mutant; smaller amounts are also present in lignins from normal pine. They arise from dihydroconiferyl alcohol via the action of peroxidases which are responsible for the radical generation steps of lignification. The structures in the complex lignin polymers are proven using 2D and 3D NMR of isolated lignin fractions.
Corrosion, Contact Resistance, and Surface Characteristics of Stamped and Hydroformed Metallic Bipolar Plates for PEMFC

In a quest for achieving sustainable mobility, improved fuel efficiency, enhanced driving performance and drastically reduced the tail-pile emissions necessitate the replacement of conventional energy conversion systems with environmentally-friendly technologies as well as lightweighting in transportation vehicles. Fuel cell technology is believed to be a promising avenue to achieve such a long desired sustainable transportation goal. However, for its widespread commercial success, there are some issues that need to be addressed. This study aims to investigate two of these underlying issues: corrosion and contact resistance in bipolar plates, which arise during the use fuel cell stacks, and are direct effects of production, material, surface, and coating conditions. Repeatability and robustness of manufacturing method (stamping, and hydroforming), corrosion and contact resistance of stainless steel bipolar plates (BPP), and tribological issues of forming dies in which bipolar plates are formed were investigated in this study. First, the effects of manufacturing conditions on formed bipolar plate quality and process repeatability were investigated. Second, corrosion and contact resistance tests for manufactured bipolar plates as well as blank stainless steel sheets were performed. Based on the corrosion test results, a faster stamping speed is found to be preferable for higher corrosion resistance and shorter production time. On the contrary, higher pressure rates in hydroforming are found to lower the corrosion resistance. Thus, a compromise between corrosion performance and production rate is needed in hydroforming for mass production purposes. According to the preliminary contact resistance tests, hydroformed bipolar plates showed better interfacial electrical conductivity than stamped plates. Also, the test results confirmed that surface coating is necessary to improve corrosion and contact properties to meet the DOE goals. Finally, relatively larger surface topography changes were observed on the manufactured bipolar plates compared to the forming die surfaces after several hundreds of BPP production.© 2010 ASME
Das physikalisch-chemische System des Blutes in seiner Beziehung zu Atmung und Kreislauf

Eine Beschreibung der physikalisch-chemischen Eigenschaften des Blutes eines normalen Individuums wurde gegeben im Zustande der Ruhe und nach korperlicher Arbeit. Die Anderungen der wichtigsten Faktoren zwischen diesen beiden Zustandsformen wurden fur Arterien und Venenblut an Hand von Kurven und Tabellen zur Anschauung gebracht. Auf die respiratorischen Anderungen wurde ebenfalls hingewiesen.
Endogenous annual rhythm of reproductive function in the non-hibernating desert ground squirrelAmmospermophihis leucurus

1. Seventeen male antelope ground squirrels (Ammospermophilus leucurus) were captured in California in early summer and maintained for nearly 2 years at a constant photoperiod of LD 12∶12 and temperature of 23 °C. Ten additional males were maintained in continuous illumination (LL) for nearly 2 years. Testes were measured monthly by laparotomy; body mass, water consumption, and daily locomotor activity were also recorded. 2. In the absence of cues to environmental seasonality — both in LD 12∶12 and LL — the testes showed strong and conspicuous cycles that resemble the natural cycle, i.e., the animals exhibited ‘endogenous circannual rhythms’. The first peak of testis size in the laboratory occurred more than 2 months prior to the usual peak in nature, and regression was protracted in the laboratory to more than twice the duration in the field. 3. Mean period (τ) of the circannual testicular rhythm (from first to second maximum) was 420 days in LD 12∶12, which is longer than that of related sciurids that hibernate (Spermophilus, Eutamias). In contrast to its hibernating relatives,A. leucurus showed no clear circannual rhythms of body mass, nor of metabolic activity as reflected by water consumption. 4. There was no association between the circannual testicular cycle and the temporal course of several parameters of circadian locomotor rhythmicity: duration (α) and amount of activity in LD 12∶12 and LL, phase relationship (ψ) of activity to the LD 12∶12 cycle, and period (τ) of the free-running circadian rhythm in LL.
The Energy of Dissociation of Mercury Molecules

The absorption spectrum of mercury vapor in the Schumann region showed three apparently continuous bands with maxima at wave-lengths 1849, 1808, and 1692. The 1849 and 1692 bands appeared without the 1808 band in the emission from an electrodeless discharge through mercury vapor. The absorption spectrum in the region 1900-1804 is correlated with a pair of potential energy curves for ${\mathrm{Hg}}_{2}$. From these curves, the energy of dissociation of ${\mathrm{Hg}}_{2}$ is 0.15 volts.
Telling our stories: Narratives as a basis for theorizing sexual harassment

(1992). Telling our stories: Narratives as a basis for theorizing sexual harassment. Journal of Applied Communication Research: Vol. 20, Telling our stories: Sexual harassment in the communication discipline, pp. 349-362.
Indentation Creep and Relaxation Measurements of Polymers

Instrumented indentation was used to characterize the mechanical response of polymeric materials. A model based on contact between a rigid probe and a linear viscoelastic material was used to calculate values for creep compliance and stress relaxation modulus for epoxy, poly(methyl methacrylate) (PMMA), and two poly(dimethyl siloxane) (PDMS) elastomers. Results from bulk rheometry studies were used for comparison to the indentation creep and stress relaxation results. For the two glassy polymers, the use of sharp pyramidal tips produced responses that were considerably more compliant (less stiff) than rheometry values. Additional study of the deformation remaining in epoxy after creep testing revealed that a large portion of the creep displacement measured was due to post-yield flow. Indentation creep measurements of the epoxy using a rounded conical tip also produced nonlinear responses, but the creep compliance values appeared to approach linear viscoelastic values with decreasing creep force. Responses measured for the PDMS were mainly linear elastic, but the filled PDMS exhibited some time-dependence and nonlinearity in both rheometry and indentation measurements.
Variation in oxytocin receptor gene (OXTR) polymorphisms is associated with emotional and behavioral reactions to betrayal

Variations in the gene that encodes the oxytocin receptor (OXTR) have been associated with many aspects of social cognition as well as several prosocial behaviors. However, potential associations of OXTR variants with reactions to betrayals of trust while cooperating for mutual benefit have not yet been explored. We examined how variations in 10 single-nucleotide polymorphisms on OXTR were associated with behavior and emotional reactions
A posteriori error estimation and dynamic adaptivity for symmetric discontinuous Galerkin approximations of reactive transport problems

A symmetric discontinuous Galerkin scheme is applied for solving reactive transport problems. An explicit a posteriori error estimator in L 2 (L 2 ) is derived for the semi-discrete scheme applied to transport with general kinetic reactions. Explicit a posteriori error estimators in terms of linear functionals and negative norms are also obtained for transport problems with simple reactions. An adaptive approach based on the a posteriori error estimators is proposed to modify the mesh dynamically. Numerical examples demonstrate the efficiency and effectivity of the estimators. Moreover, it is shown in this study that the proposed adaptivity eliminates the need of slope limiters. � 2005 Elsevier B.V. All rights reserved.
The crystal structure of diazomethyl β-d-galactopyranosyl ketone

Abstract The title compound (C 8 H 12 N 2 O 6 ) crystallizes in the orthorhombic space group P 2 1 2 1 2 1 ( Z = 4), with a = 4.871(1), b = 11.136(2), c = 18.301(2) A. The structure was solved by the multi-solution techique and refined by full-matrix least-squares to a final R -index of 0.042. The compound adopts the 4 C 1 ( d ) conformation. Bond lengths in the diazoacetyl group are consistent with the presence of a zwitterion.
Metastasis of primary lung carcinoma to the breast: a systematic review of the literature

Abstract Background The purpose of this systematic review was to summarize previously published case reports of primary lung carcinoma metastasis to the breast to assess common clinical and pathologic features and management strategies. Materials and methods Case reports describing breast metastasis of primary lung carcinoma were systematically evaluated in MEDLINE and EMBASE. Results Thirty-one reported cases of non-small-cell lung carcinoma (NSCLC) metastasized to the breast were identified, along with eight cases of small-cell lung carcinoma. Sixty-seven percent of reported NSCLC metastases to the breast were detected metachronously with the primary lung abnormality, whereas 80% of small-cell lung carcinoma breast metastases appeared synchronously. Thyroid transcription factor 1 was found to be expressed in 58% of total NSCLC breast metastases, including 83% of those of adenocarcinoma origin. Therapeutic strategies among NSCLC cases varied widely, and only 36% of NSCLC breast metastasis patients were administered chemotherapy. Additional sites of metastasis in these cases are summarized as well. Conclusions It is recommended to include metastatic lung cancer in the differential diagnosis of patients presenting with a breast abnormality in the context of a suspected lung cancer. Thyroid transcription factor 1 expression should be examined in these cases. The metachronous versus synchronous nature of lung carcinoma metastasis to the breast has consequences for both detection of the primary and secondary lesions and patient outlook. Clinical correlation is vital to effective management of the care of patients harboring these atypical secondary lesions.
Three-dimensional multi-resolution statistical reconstruction for tomosynthesis

In this paper, we propose a novel three-dimensional maximum a posteriori (MAP) algorithm for tomosynthetic reconstruction. The motivation of this work is to improve the image quality while simultaneously reduce the computational cost that is the most challenging problem of the statistical (Bayesian) reconstruction algorithm. The proposed method utilizes a multi-resolution representation for both reconstruction and projections. The imaged object is reconstructed from the coarsest scale to the finest scale, sequentially. Simulations are presented showing that the proposed algorithm produces better imaged-quality and leads to faster convergence than the alternative methods.
Evaluation of Yield and Quality of Cheddar Cheese Manufactured from Milk with Added Whey Protein Concentrate

Abstract Cheddar cheese was produced from whole milk with blends of whey protein concentrates added. Two whey protein concentrate powders containing 35 or 55% protein were each reconstituted to a 15% (wt/wt) suspension and heat treated at 70°C for 15min. Addition of the denatured whey protein concentrate suspension to the milk was at 5 or 10% by weight of the milk. Addition of reconstituted partially denatured whey protein concentrate increased cheese yields from 1.4 to 6.2% above those of the control on a 63% solids basis. The only significant ( P
An Online Guided E-Journal Exercise in Pre-Clerkship Years: Oxidative Phosphorylation in Brown Adipose Tissue.

The rationale for this mandatory, guided online e-journal exercise is to foster the ability of students to independently read medical and scientific literature in a critical manner and to integrate journal reading with their basic science knowledge. After a lecture on oxidative phosphorylation, students were assigned to read an article on brown adipose tissue published in New England Journal of Medicine and were guided to analyze the article by answering online questions. After two iterations, student surveys about the project, its key pedagogical features, and ways to improve it suggest that the students perceived these exercises as active learning, which is clinically relevant and built on their course material. Furthermore, students agreed that the e-journal project was useful for learning how to read an article, for reviewing the material learned in class, and for promoting evidence-based medicine. This online e-journal exercise models some aspects students will experience as future physicians, where it is essential to keep up with literature and extract relevant information on a tight physician's schedule. This study demonstrated the usefulness of guided e-journal exercises as a simple effective active teaching tool for preclinical medical students, which can also be used for prehealth undergraduate programs.
Minimizing crosstalk in high-speed differential buses by optimizing power/ground and signal assignment

Vias in packages and boards, land-grid-array pins, and connector pins introduce significant crosstalk noise in high-speed differential buses. In this paper, we propose an algorithm that minimizes crosstalk noise by optimizing power/ground distribution as well as differential signal assignment. Experimental results demonstrate its high efficiency and significant electrical benefit.