cssi/SciSciGPT-SciSciNet huggingface dataset:
Biosolids Processing Effects on First- and Second-Year Available Nitrogen

Simple, reliable estimates of biosolids N availability are needed to develop land application programs that will benefit crops without risk of excess nitrate leaching. This study was conducted to assess the effect of biosolids processing on plant available nitrogen (PAN) release during the first and second growing seasons after application. We compared 14 sources of biosolids and a range of inorganic N rates in two replicated field experiments on established tall fescue (Festuca arundinacea Schreb.). The biosolids encompassed a range of treatment and dewatering/drying processes. A single biosolids application was made in May of the first year, and tall fescue yield and N uptake were measured by harvest for the next two growing seasons. Inorganic N was split across multiple applications each year. Fertilizer efficiency regression equations were developed for the inorganic N treatments, and used to calculate biosolids PAN from N uptake data. Year 1 PAN was similar across a range of biosolids treatment processes. For nonlagoon biosolids, PAN averaged 37 ± 5% of total biosolids N. Lagoon biosolids PAN ranged from 8 to 25% of total N, with the oldest, most stable biosolids having the lowest PAN. Year 2 PAN averaged 13 ± 2% for nonlagoon biosolids, excluding heat-dried materials, which were lower (5 to 8%). Our calculations indicated that about half of the Year 2 PAN became available during the cool season, suggesting that winter cover cropping may be needed to reduce the potential for nitrate leaching loss in summer annual cropping systems.
Cellular mechanisms controlling light-stimulated gravitropism: role of calcium.

An irradiation with visible light can alter the gravitropic responsiveness of shoots and roots. This indicates that light must affect some biochemical process in plant cells which is the same as, or importantly influences, a biochemical process that regulates gravitropism. In many cases, the light receptor for this effect is the pigment phytochrome, which initiates a variety of important photomorphogenic responses in plants. Recent results suggest that both gravistimulation and phytochrome photoactivation result in altered Ca2+ transport into and out of the affected cells. This article reviews the evidence that these Ca2+ fluxes may be the common biochemical process which modulates both gravitropism and photomorphogenesis.
Two characterization theorems in complementarity theory

In this paper, we establish two characterization theorems for the linear and non-linear complementarity problems. Theorem 1 concerns the local uniqueness of a solution to a linear complementarity problem. Theorem 2 provides a necessary and sufficient condition for the differentiability of a solution to a parametric non-linear complementarity problem.
Near- and far-field effects on molecular energy level alignment at an organic/electrode interface

We investigate the evolution of the interfacial electronic structure at the interface of (sub)monolayer vanadyl naphthalocyanine (VONc) on highly oriented pyrolytic graphite (HOPG). Both the vacuum...
Life Cycle of an Electropore: A Molecular Dynamics Investigation of the Electroporation of Heterogeneous Lipid Bilayers (PC:PS) In the Presence of Calcium Ions

To aid in understanding the mechanism of electric field-driven pore formation in lipid bilayers, we propose a scheme for characterizing the life cycle of a transient membrane electropore, from the formation of the initial defect to the restoration of the intact bilayer. We apply this analysis to heterogeneous phospholipid bilayers (phosphatidylcholine:phosphatidylserine, PC:PS) in the presence of calcium ions. Previous reports of molecular dynamics (MD) simulations of similar PC:PS systems containing Ca2+ [1,2] are consistent with experimental observations [3]. In this study we assembled systems containing varying amount of PC, PS, and Ca2+ and observed how long it took each bilayer to porate after the application of an electric field. We also measured the effect of Ca2+ on pore lifetime (the time it takes to restore the porated bilayer after removal of the electric field). We find that systems containing Ca2+ are more difficult to electroporate, and that this effect is magnified in systems containing PS. We also observe that Ca2+ has little effect on pore lifetime, but that PC:PS systems have shorter lifetimes than pure PC systems. Finally, we report binding isotherms for Ca2+ and PC:PS bilayers, an additional metric for the validity of phospholipid bilayer simulations containing calcium.[1] Bockmann, R. A., and H. Grubmuller. 2004. Multistep binding of divalent cations to phospholipid bilayers: A molecular dynamics study. Angewandte Chemie-International Edition 43:1021-1024.[2] Vernier, P. T., M. J. Ziegler, and R. Dimova. 2009. Calcium binding and head group dipole angle in phosphatidylserine-phosphatidylcholine bilayers. Langmuir 25:1020-1027.[3] Sinn, C. G., M. Antonietti, and R. Dimova. 2006. Binding of calcium to phosphatidylcholine-phosphatidylserine membranes. Colloids and Surfaces A-Physicochemical and Engineering Aspects 282:410-419.
Sequential price and quantity decisions under supply and demand risks

Abstract Firms need to deal with not only risks from stochastic demand but also risks from supply side. The supply side risk may be due to parts/service outsourcing, third party logistics, or random yield in production processes. In this paper, we study how firms sequentially make price and quantity decisions under these two risks. The first question we try to answer is how these two risks affect the decisions and profits of the firm. We find that increased supply risk usually causes increased quantity/stocking decision, however, there exists a threshold level of supply risk above which the firm reduces quantity/stocking amount as supply risk increases. This observation may be used in a supply chain setting, where reduction of the supply risk can cause higher delivered quantity and improve supply chain performance. This observation also provides support and insights on prioritizing the risk reduction efforts from marketing and operations to achieve better coordination. At the same time, reduction of the risks help not only firms but also consumers as the optimal price decreases. To further improve decision making process under both uncertainties, we study the impact from information revelation and postponement of decisions. We compare results from different sequential decision making cases. As illustrated in the paper, firms gain competing advantage when decision postponement is available and this advantage becomes further significant as the risks increase. Our numerical examples also indicate that price postponement strategy is usually preferred but the relative profit difference between price postponement and quantity postponement become smaller as consumers become more sensitive to the price.
Characterization of 2-(2-Methoxyethoxy)ethanol Substituted Phosphazene Polymers Using Pervaporation, Solubility Parameters and Sorption Studies

Two linear phosphazene polymers were synthesized with differing amounts of hydrophilic 2-(2-methoxyethoxy)ethanol (MEE) and hydrophobic 4-methoxyphenol (MEOP) substituted on the backbone. These high polymers were cast into membranes and their permeability to water, methanol, ethanol, and 2-propanol was evaluated as a function of temperature. An additional polymer with a low content of MEE was studied for water permeation and was characterized by trace flux. At higher levels of MEE on the backbone, fluxes of all solvents increased. Solubility also was found to increase with increasing MEE content for all solvents except water. Unexpectedly, water was found to be less soluble in the higher MEE polymer, although higher membrane fluxes were observed. Diffusion coefficients showed the following trend: methanol ≫ 2-propanol > ethanol ≫ water. Finally, the affinity of solvents and polymers was discussed in terms of Hansen solubility parameters. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 939–945, 2005
Fracture initiation under gross yielding: Strain energy density criterion

Abstract The damage of metal alloys at the continuum level can be described by a combined process of yielding and fracture. Yielding is generally associated with excessive distortion and fracture with excessive dilatation. With the increased use of low strength alloys, gross yielding can often precede the initiation of macrocracking. This paper applies the strain energy density concept for examining failure by crack growth in a fully plastic material in order to show that the criterion applies to linear elastic as well as nonlinear plastic materials. The incremental theory of plasticity is employed in conjunction with the finite element method for determining the stresses in a tensile specimen containing a center crack. Net section yield is developed. Calculated are the different levels of intensity of yielding around the crack. As in the elastic case, crack growth in a fully plastic material also tends to coincide with the direction along which the strain energy density function dW/dV attains a relative minimum. The onset of crack growth is assumed to occur when (dW/dV)min reaches some critical value (d W/d V) c ∗ which must now be obtained from the true stress and strain curve of the material undergoing gross yielding.
GM1 monosialoganglioside pretreatment protects against soman-induced seizure-related brain damage.

The effects of GM1 monosialoganglioside pretreatment on brain damage resulting from soman-induced seizure activity were examined in this study. Male Sprague-Dawley rats were infused with GM1 via an osmotic minipump connected through a permanent cannula implanted intracerebroventricularly and challenged with soman (83 μg/kg, i.e., 1.25 × LD50) 4 d after initiation of GM1 infusion. Electrocorticographic recordings were monitored via indwelling cortical electrodes. Twenty-seven hours after soman administration, anesthetized rats were euthanized via transcardial perfusion with buffered paraformaldehyde. Brains were processed for hematoxylin and eosin (HE however, only five developed SE. The remaining six recovered and had no brain damage. In addition, the latter group showed a significantly higher residual AChE reactivity in the basolateral amygdala compared to rats that developed SE. Quantitative image analysis of MAP2-immunostained brain sections from the five GM1-infused rats that developed SE showed a 85.9±14.1% reduction in cross-sectional area of necrosis in the piriform cortex when compared to the somanchallenged rats that were not infused with GM1. This was paralleled by a pronounced decrease in morphological evidence of damage on H&E and CV-stained serial sections. Considerable brain region/treatment group variability was seen with GFAP immunostaining. The present findings demonstrate that GM1 pretreatment interferes with the development of SE and significantly alleviates brain damage resulting from soman-induced seizures.
Changes in lung mechanics and histamine responsiveness after sequential canine adenovirus 2 and canine parainfluenza 2 virus infection in beagle puppies.

We determined the effects of an immediately antecedent viral lower respiratory tract infection (LRI) on the severity of clinical illness, changes in lung function and airway histamine responsiveness produced by a subsequent LRI in 9–12 week old beagle puppies inoculated with canine adenovirus 2, followed in 2 weeks by inoculation with canine parainfluenza 2 virus (CAV2-CPI2, n = 7). We compared their acute responses to puppies infected with CPI2 alone (n = 5), CAV2 alone (n = 7), and no infection (control, n = 6). Puppies inoculated with either virus alone developed a LRI 3 to 6 days after inoculation which resolved by 12–14 days after inoculation. However, the illness was more severe in the CAV2 group. In the CAV2-CPI2 group, CPI2 infection following CAV2 infection resulted in a clinical illness nearly comparable to that observed with CAV2 alone. Whereas in control and CPI2 puppies, lung resistance (RL) decreased and dynamic lung compliance (Cdyn) increased during the study due to normal growth, RL increased and Cdyn remained unchanged in the CAV2 group. In contrast, RL did not change and Cdyn increased in the CAV2-CPI2 group. Airway histamine responsiveness in the CAV2-CPI2 group increased during infection with CPI2 and was similar to that observed with CAV2 alone. In contrast, infection with CPI2 alone produced a small, but non-significant increase in histamine responsiveness. The duration of the increase in histamine responsiveness was not prolonged in the CAV2-CPI2 group in comparison to CPI2 or CAV2 alone. However, the length of clinical illness was extended in the CAV2-CPI2 group in comparison to the other infected groups. These data suggest that an immediately antecedent viral LRI can potentiate the clinical and physiologic effects of a subsequent viral LRI. Pediatr Pulmonol 1991; 10:236–243.
Efficient fault-tolerant broadcasts

Abstract Broadcasting is among the most useful primitives in a distributed system for the interaction among processes. We present a simple scheme to implement broadcasting on an asynchronous network. Our scheme does not use the conventional time-out approach to manage faults and thus is not based on fault detection. We investigate a single fault of a fail-stop link and show that at most 2( n − 1) messages are generated in a network of n nodes to broadcast a message from a node to all other nodes, in spite of a link failure.
Comparison of toluene-induced locomotor activity in four mouse strains.

The mechanisms by which abused inhalants exert their neurobehavioral effects are only partially understood. In research with other drugs of abuse, specific inbred mouse strains have been useful in exploring genetic loci important to variation in behavioral reactions to these drugs. In the present investigation, mice from three inbred strains (Balb/cByj, C57BL/6J and DBA/2J) and one outbred strain (Swiss Webster) were studied for their acute and chronic sensitivity to toluene-induced changes in locomotor activity. Mice were exposed to toluene (0, 100, 2000, 8000, and 10,000 ppm) for 30 min in static exposure chambers equipped with activity monitors. In the acute condition, concentrations of toluene or =8000 ppm induced temporally biphasic effects with initial increases in activity followed by hypoactivity. Between-group differences in absolute locomotor activity levels were evident. The inbred Balb/cByj and DBA/2J strains as well as the outbred Swiss Webster strain of mice showed greater increases in activity after an acute challenge exposure to 2000 ppm than the inbred C57BL/6J strain. The same animals were then exposed 30 min/day to 8000 ppm toluene for 14 consecutive days. Re-determination of responses to 2000-ppm challenge exposures revealed that sensitization developed in locomotor activity and that the DBA/2J strain showed the greatest increase in sensitivity. These baseline differences in acute sensitivity and the differential shifts in sensitivity after repeated exposures among the inbred mouse strains suggest a genetic basis for the behavioral effects to toluene. The results support the notion that like for other drugs of abuse, using various strains of mice may be useful for investigating mechanisms that underlie risk for inhalant abuse.
Phase 2 early afterdepolarization as a trigger of polymorphic ventricular tachycardia in acquired long-QT syndrome : direct evidence from intracellular recordings in the intact left ventricular wall

Background—This study examined the role of phase 2 early afterdepolarization (EAD) in producing a trigger to initiate torsade de pointes (TdP) with QT prolongation induced by dl-sotalol and azimilide. The contribution of transmural dispersion of repolarization (TDR) to transmural propagation of EAD and the maintenance of TdP was also evaluated. Methods and Results—Transmembrane action potentials from epicardium, midmyocardium, and endocardium were recorded simultaneously, together with a transmural ECG, in arterially perfused canine and rabbit left ventricular preparations. dl-Sotalol preferentially prolonged action potential duration (APD) in M cells dose-dependently (1 to 100 μmol/L), leading to QT prolongation and an increase in TDR. Azimilide, however, significantly prolonged APD and QT interval at concentrations from 0.1 to 10 μmol/L but shortened them at 30 μmol/L. Unlike dl-sotalol, azimilide (>3 μmol/L) increased epicardial APD markedly, causing a diminished TDR. Although both dl-sotalol and azimi...
Baroreflex actions of substance P microinjected into the nucleus tractus solitarii in rat: a consequence of local distortion

Abstract Biologically active substance P (SP) (1000 ng in 0.1 μl saline) microinjected into the nucleus tractus solitarii (NTS) of 25 rats did not affect arterial pressure, heart rate, or the baroreceptor reflex. However, microinjection of saline alone in volumes greater than 0.3 μl consistently elicited hypotension and bradycardia followed occasionally by transient hypertension. These data suggest that previously reported cardiovascular effects of SP microinjected into the NTS resulted from local distortion.
Mixture distributions for modelling demand during lead time

A mixture distribution approach to modelling demand during lead time in a continuous-review inventory model is described. Using this approach, both lead time and demand per unit time can follow state-dependent distributions. By using mixtures of truncated exponentials functions to approximate these distributions, mixture distributions that can be easily manipulated in closed form can be constructed as the marginal distributions for lead time and demand per unit time. These are then used to approximate the mixture of compound distributions for demand during lead time. The technique is illustrated by first applying it to a ‘normal-gamma’ inventory problem, then by modelling a problem with empirical distributions for lead time and demand per unit time.
Calculus Students' Use and Interpretation of Variables: Algebraic vs. Arithmetic Thinking

Abstract The ability to use and interpret algebraic variables as generalized numbers and changing quantities is fundamental to the learning of calculus. This study considers the use of variables in these advanced ways as a component of algebraic thinking. College introductory calculus students' (n = 174) written responses to algebra problems requiring the use and interpretation of variables as changing quantities were examined for evidence of algebraic and arithmetic thinking. A framework was developed to describe and categorize examples of algebraic, transitional, and arithmetic thinking reflected in these students' uses of variables. The extent to which students' responses showed evidence of algebraic or arithmetic thinking was quantified and related to their course grades. Only one third of the responses of these entering calculus students were identified as representative of algebraic thinking. This study extends previous research by showing that evidence of algebraic thinking in students' work was po...
Fine Structure of a Genetic Region in Bacteriophage

This paper describes a functionally related region in the genetic material of a bacteriophage that is finely subdivisible by mutation and by genetic recombination. The group of mutants resembles similar cases which have been observed in many organisms, usually designated as "pseudo-alleles." (See reviews by Lewis [1] and Pontecorvo [2].) Such cases are of special interest for their bearing on the structure and function of genetic determinants. The phenomenon of genetic recombination provides a powerful tool for separating mutations and discerning their positions along a chromosome. When it comes to very closely neighboring mutations, a difficulty arises, since the closer two mutations lie to one another, the smaller is the probability that recombination between them will occur. Therefore, failure to observe recombinant types among a finite number of progeny ordinarily does not justify the conclusion that the two mutations are inseparable but can only place an upper limit on the linkage distance between them. A high degree of resolution requires the examination of very many progeny. This can best be achieved if there is available a selective feature for the detection of small proportions of recombinants. Some preliminary results are here presented of a program designed to extend genetic studies to the molecular (nucleotide) level.
Optimization of whole-transcriptome amplification from low cell density deep-sea microbial samples for metatranscriptomic analysis

Limitation in sample quality and quantity is one of the big obstacles for applying metatranscriptomic technologies to explore gene expression and functionality of microbial communities in natural environments. In this study, several amplification methods were evaluated for whole-transcriptome amplification of deep-sea microbial samples, which are of low cell density and high impurity. The best amplification method was identified and incorporated into a complete protocol to isolate and amplify deep-sea microbial samples. In the protocol, total RNA was first isolated by a modified method combining Trizol (Invitrogen, CA) and RNeasy (QIAGEN, CA) method, amplified with a WT-Ovation™ Pico RNA Amplification System (NuGEN, CA), and then converted to double-strand DNA from single-strand cDNA with a WT-Ovation™ Exon Module (NuGEN, CA). The products from the whole-transcriptome amplification of deep-sea microbial samples were assessed first through random clone library sequencing. The BLAST search results showed that marine-based sequences are dominant in the libraries, consistent with the ecological source of the samples. The products were then used for next-generation Roche GS FLX Titanium sequencing to obtain metatranscriptome data. Preliminary analysis of the metatranscriptomic data showed good sequencing quality. Although the protocol was designed and demonstrated to be effective for deep-sea microbial samples, it should be applicable to similar samples from other extreme environments in exploring community structure and functionality of microbial communities.
Performance evaluation of minimum average correlation energy filters

A new SDF type correlation filter referred to as the minimum average correlation energy (MACE) filter has been recently described in the literature. In this paper, we experimentally address the distortion tolerance and noise properties of this filter. The MACE filter has attractive properties that include: easily detectable peaks, distortion invariance, simplified training set selection, solutions to input bias effects, performance in noise and real background clutter, and less clutter with its reduced number of training set images. Each of these properties is investigated in detail in this paper.
Culturally interpreted symptoms or culture-bound syndromes: A cross-cultural review of nerves

This paper explores a new approach to culture-specific mental disorders through cross-cultural examination of nerves. A number of case studies are presented from contrasting cultures. It is proposed that nerves be considered a culturally interpreted symptom rather than being culture-bound.
Production of high-current metal ion beams

Abstract The increasing usage of ion implantation to modify the chemical and surface sensitive mechanical properties of materials typically requires fluences of 10 17 ions/cm 2 . In order to implant test hardware (e.g., ball bearings) to such high influences in a reasonable period of time it is necessary to employ ion beam currents with intensities of a hundred-microampere or more. This paper will describe the modifications made in the ion source of the NRL Extrion/Varian 200-20A2F ion implanter to produce high current metal ion beams utilizing an internal chlorination technique. Several charge material source geometries and carrier gas combinations have been tried and compared. Beam currents of 100 μA or more intensity have been routinely obtained for most metal species attempted, with 500–1000 μA intensities obtained for some commonly run species (e.g., 52 Cr + and 48 Ti + ). This paper will present (1) a compilation of ion species and intensities obtained, (2) typical ion source operating parameters and lifetimes, and (3) evidence of ion source “poisoning effects”.
Retinal degeneration in rdgA mutants of Drosophila melanogaster meigen (diptera : drosophilidae)

Abstract To better understand the roles of particular defective genes affecting the Drosophila (Diptera : Drospphilidae) visual system and the ensuing cell biology they order, we utilized 2 mutant alleles of the rdgA gene, namely rdgAPC47 and rdgABS12. Each allele causes the expression of a different pattern of retinal degeneration. We examined ultrastructurally the time course and cell specificity of degeneration. The rdgAPC47 mutant has a relatively normal compound eye and lamina ganglionaris (1st optic neuropile) upon pupal emergence. Photoreceptors, especially R1–6, degenerate in one week and their terminals in the lamina are largely phagocytosed by glia. R7/8 receptors and 2nd-order interneurons are somewhat spared by comparison. By contrast, the cytology of the photoreceptors of rdgABS12 is abnormal upon eclosion. However, even though abnormal, R1–6 and R7/8 do project axons to higher centers; there are even some normal properties in the optic cartridges (synaptic glomeruli of R1–6 terminals) in the lamina. A week later, there is little further demise of R1–6 terminals in rdgABS12, revealing a surprising survival of structure in the lamina.
A rare case of self-incompatibility in arctic plants : Draba palanderiana (Brassicaceae)

Abstract During the last decades, it has been shown that arctic plants show larger variation in reproductive strategies than traditionally assumed. Obligate outcrossing based on a self-incompatibility system is, however, very rare in the typically harsh, insect-poor arctic environment. Here we present the second, to our knowledge, documented example of a fully self-incompatible arctic species, Draba palanderiana Kjellm. Because of its large, scented flowers and frequently aborted fruits it has been suggested that this species is strictly outcrossing. To test this hypothesis, we conducted a pollination experiment with two populations from arctic North America. Pollen stainabilities were above 80% in most plants. Full female and male fertility was demonstrated by crosses resulting in fertile F1 offspring. In contrast, no viable seeds were obtained after spontaneous or hand-facilitated selfing, demonstrating that these D. palanderiana populations are fully self-incompatible and thus obligately outcrossing.
Search and leisure with idiosyncratic endowment shocks in a random-matching model

Abstract Agents who realize idiosyncratic endowment shocks (High and Low) choose between leisure and searching for a trading partner. In the non-monetary economy there are two cases: everyone enjoys leisure or everyone enters the market to barter. In the first case, money can generate an equilibrium in which all agents enter the market. In the second, money can generate an outcome impossible without money, in which High agents trade while Low agents rest. Money affects the real side of the economy by driving Low quality goods out of the market, improving the quality of traded goods.
Third-Line Chemotherapy and Novel Agents for Metastatic Germ Cell Tumors

Although germ cell tumors (GCT) are among the most curable solid tumors, a subset of patients with GCT experience relapse or progression despite appropriate cisplatin-based therapy or first-line salvage therapy. This article describes the molecular mechanisms of cisplatin resistance, outlines single-agent chemotherapy and combination chemotherapy regimens that are active against GCT in the third-line or later setting, discusses the use of drug therapy for treating growing teratoma syndrome and teratoma with malignant transformation, outlines novel agents used to treat GCT, and highlights ongoing clinical trials and future directions in the treatment of refractory GCT.
3′,5′ Cyclic Adenosine Monophosphate Mediates the Salmon Calcitonin-Induced Increase in Hypothalamic Tyrosine Hydroxylase Activity1

This study examined the effect of salmon calcitonin (sCT) on hypothalamic tyrosine hydroxylase (TH) activity and evaluated the cellular signaling mechanisms involved in the response. Fetal hypothalamic cells were cultured in a defined medium and treated with sCT and/or specific protein kinase inhibitors on day 14 in vitro. sCT (0.1–10 nm) increased both TH activity and cellular cAMP content in a concentration-dependent manner. sCT (10 nm) increased TH activity to 150–175% of control values and resulted in a 10-fold increase in cellular cAMP content. Both the C1a and C1b CT receptor isoforms were present in the cultures, as assessed by RT-PCR. Rp-adenosine 3′,5′-cyclic monophosphothioate (Rp-cAMPS), a cAMP antagonist, and H-8, a cyclic nucleotide kinase inhibitor, blocked the sCT-induced increase in TH activity, with complete abolition of the response observed at concentrations of 1 mm and 5 μm, respectively. sCT (10 nm) increased radiolabeled phosphate incorporation into TH protein to 169% of control valu...
Effects of viscoelasticity in the high Reynolds number cylinder wake

At ReD 3900, Newtonian flow past a circular cylinder exhibits a wake and detached shear layers which have transitioned to turbulence. It is the goal of the present study to investigate the effects which viscoelasticity has on this state and to identify the mechanisms responsible for wake stabilization. It is found through numerical simulations (employing the FENE-P rheological model) that viscoelasticity greatly reduces the amount of turbulence in the wake, reverting it back to a state which qualitatively appears similar to the Newtonian mode B instability which occurs at lower Re. By focusing on the separated shear layers, it is found that viscoelasticity suppresses the formation of the Kelvin‐Helmholtz instability which dominates for Newtonian flows, consistent with previous studies of viscoelastic free shear layers. Through this shear layer stabilization, the viscoelastic far wake is then subject to the same instability mechanisms which dominate for Newtonian flows, but at far lower Reynolds numbers.
Random interbreeding between cryptic lineages of the Common Raven: evidence for speciation in reverse

DNA sequence studies frequently reveal evidence of cryptic lineages in morphologically uniform species, many of which turn out to be evolutionarily distinct species. The Common Raven (Corvus corax) includes two deeply divergent mtDNA lineages: one lineage seems restricted to western North America and the other is Holarctic in distribution. These deep clades hint of the possibility of cryptic species in the western United States. We tested this hypothesis in a population consisting of an equal proportion of both mtDNA clades, by quantifying mating patterns and associated fitness consequences with respect to mtDNA. We also tested for morphological, behavioural and ecological correlates of sex and mtDNA clade membership. Mate pairings were random with respect to mtDNA clades, and there were no differences in reproductive success between assortatively and nonassortatively mated pairs. We found no differences in survival or resource use between clades. There were no differences in morphological or behavioural characters between mtDNA clades, except one clade trended towards greater mobility. These results suggest there are no barriers to gene flow between mtDNA clades and argue that the mtDNA clades have remerged in this population, likely due to a lack of ecological or signal differentiation between individuals in each lineage. Hence, in Common Ravens, phylogeographic structure in mtDNA is a reflection of likely past isolation rather than currently differentiated species.
Soil-geotextile interaction: Evaluation of membrane support

Abstract A general expression for evaluating the increase of bearing, capacity due to membrane action based on strict equilibrium conditions is presented. In order to provide closed form solutions for design purposes, an average membrane action is also defined. Particular expressions of the average membrane action are obtained assuming constant — as most models do — and variable strain deformation of the membrane. The general expression derived herein provides a valuable framework to compare the most commonly used expressions. This comparison is made in terms of dimensionless parameters. The most commonly used design procedures to quantify the membrane action provided by the inclusion of geotextiles on soft soils underlying granular fills are reviewed. Circular and parabolic shapes are used to simulate the geotextile deformation. It is shown that independently of the model used and geotextile deformation shape assumed, comparable values for membrane support for relatively small rutting ratios are obtained. On the contrary, for large rutting ratios, the choice of membrane support model and geotextile deformation shape has significant influence on the results, the latter being the most influential one.
Probing lysozyme conformation with light reveals a new folding intermediate.

A means to control lysozyme conformation with light illumination has been developed using the interaction of the protein with a photoresponsive surfactant. Upon exposure to the appropriate wavelength of light, the azobenzene surfactant undergoes a reversible photoisomerization, with the visible-light (trans) form being more hydrophobic than the UV-light (cis) form. As a result, surfactant binding to the protein and, thus, protein unfolding, can be tuned with light. Small-angle neutron scattering (SANS) measurements were used to provide detailed information of the protein conformation in solution. Shape-reconstruction methods applied to the SANS data indicate that under visible light the protein exhibits a native-like form at low surfactant concentrations, a partially swollen form at intermediate concentrations, and a swollen/unfolded form at higher surfactant concentrations. Furthermore, the SANS data combined with FT-IR spectroscopic analysis of the protein secondary structure reveal that unfolding occur...
Arylhydrazines as probes of hemoprotein structure and function

Abstract The reactions of arylhydrazines (ArNHNH2) or aryldiazenes (ArNNH) with simple iron porphyrins or with hemoproteins that have relatively open active sites, including hemoglobin, myoglobin, cytochrome P450, chloroperoxidase, catalase, prostaglandin synthase, and indoleamine-2,3-dioxygenase yield σ-bonded aryl-iron complexes. Denaturation of the protein complexes under aerobic, acidic conditions shifts the aryl group to the porphyrin nitrogens and produces mixtures of the four possible N-arylprotoporphyrin IX regioisomers. The regioisomers are obtained in approximately equal amounts if the iron-to-nitrogen shift occurs outside of the protein but the ratio of isomers differs if the rearrangement is controlled by the protein. Only in the case of cytochrome P450 enzymes can the shift be induced to occur without denaturation of the protein. The isomer ratios obtained when the shift occurs in the intact active site provide direct experimental information on the active site topology and dynamics. Topological information has thus been obtained for cytochromes P450 1A1, 1A2, 2B1, 2B2, 2B4, 2B10, 2B11, 2E1, 11A1, 51, 101, 102, and 108. In contrast to hemoproteins with open active sites, conventional peroxidases react with arylhydrazines to give δ-meso-aryl adducts and covalent protein adducts. Reaction with the δ-meso edge but not the heme iron provides key evidence that restricting access of substrates to the ferryl oxygen helps direct the reaction towards peroxidase rather than peroxygenase catalysis.
Synthesis and thermal responsiveness of self-assembled gold nanoclusters

A simple and versatile approach was developed to generate hierarchical assemblies of ultra-small gold nanocluster thin films using the combination of galvanic reaction and a block copolymer coordinated with gold complex. Variation of the temperature allows effective control over the optical response of these stimuli-responsive organic-nanocluster hybrid structures.
The Reactivity of HCI and Methyltrichlorosilane with Silicon Carbide Surfaces

This work explores the reactivity of HCI and methyltrichlorosilane (MTS) with polycrystalline β-silicon carbide (SiC) surfaces using temperature-programmed desorption (TPD) and Auger electron spectroscopy. HCl is a corrosive gas that inhibits SiC deposition. The results show that HCl is adsorbed by SiC, forming a stable surface chloride that could inhibit SiC deposition. TPD shows that chlorine desorbs as HCI or SiCl4, confirming that HCl can etch SiC surfaces. Desorption is rate-limited by the breaking of Si-Cl bonds. MTS is also adsorbed by SiC; its desorption is similar to that of HCI.
TESTS FOR FRACTIONAL INTEGRATION: A MONTE CARLO INVESTIGATION

. The performance of the Geweke-Porter-Hudak (GPH) test, the modified rescaled range (MRR) test and two Lagrange multiplier (LM) type tests for fractional integration in small samples is examined using Monte Carlo methods. Both the GPH and MRR tests are found to be robust to moderate autoregressive moving-average components, autoregressive conditional heteroskedasticity effects and shifts in the variance. However, these two tests are sensitive to large autoregressive moving-average components and shifts in the mean. It is also found that the LM tests are sensitive to deviations from the null hypothesis. As an illustration, the GPH test is applied to two economic data series.
Seismogram synthesis for azimuthally anisotropic media with a single slowness integration

SUMMARY The computation of exact synthetic seismograms for azimuthally anisotropic (AA) models with a frequency-slowness integration method requires two horizontal slowness integrations. However, a single slowness integration that is exact for azimuthally isotropic media requires much less computation time, and has therefore been considered for the AA case as well. As a single slowness integration leads to traveltime and amplitude errors, it should be used for AA media only if these errors are negligible. In this paper we discuss the errors. and outline how they can be estimated. The main contribution to the single-integration traveltime error comes from incorrect group (ray) velocities in the single-integration case. The singleintegration group velocities are always greater than or equal to the true group velocities, causing traveltimes to be too small. If there are cusps in the groupvelocity surface, not only may the traveltimes be wrong, but there may also be arrivals missing from the seismograms. In layered AA media a minor contribution to the single-integration error arises from not allowing the ray to leave the sagittal plane. The resulting traveltime error is opposite in sign, but much smaller than the traveltime error caused by incorrect group velocities. Amplitudes may be incorrect even though traveltimes are accurate. However, this can only be the case for certain isolated sagittal planes, such as symmetry planes; in other sagittal planes amplitude errors and traveltime errors go together. To decide whether single-integration amplitudes will be accurate one should compute the sagittal velocity curves for single and double integration for a range of azimuths. If the velocity errors are insignificant, then the amplitudes will be accurate for all sagittal planes.
Characterization of Fe(II) oxidizing bacterial activities and communities at two acidic Appalachian coalmine drainage-impacted sites.

Characterization of Fe(II) oxidizing bacterial activities and communities at two acidic Appalachian coalmine drainage-impacted sites
Deforesting logical form

This paper argues against Logical Form (LF) as an intermediate level of representation in language processing. We apply a program transformation technique called deforestation to demonstrate the inessentiality of LF in a parsing system that builds semantic interpretations. We consider two phenomena, Quantifier Raising in English and Wh-movement in Chinese, which have played key roles in the broader argument for LF. Deforestation derives LF-free versions of these parsing systems. This casts doubt on LF's relevance for processing models, contrary to suggestions in the literature.
Delayed clearance of transmitter and the role of glutamate transporters at synapses with multiple release sites

The roles of glutamate diffusion, uptake, and channel kinetics in shaping the AMPA receptor EPSC were examined at a calyceal synapse. The EPSC decay was described by three exponential components: two matching desensitizing channel kinetics, and a third component at least 10 times slower. The slowest component had identical voltage dependence to the steady-state AMPA current and was selectively increased and prolonged by blockade of glutamate uptake, indicating that the slow EPSC represented rebinding of glutamate at partially desensitized AMPA receptors. The data were in strong agreement with the predictions of a model of transmitter diffusion from multiple release sites into a large synaptic cleft. Within the first millisecond after release, transmitter concentrations in the cleft fell below millimolar levels, causing the fastest parts of the EPSC to be shaped by channel kinetics. The slowest component was determined by the removal over tens of milliseconds of the final 10–100 microM glutamate by diffusion and uptake. The data and modeling indicate that transmitter uptake and cooperation between release sites are significant determinants of a slow “tail” of glutamate in the synaptic cleft. This slow clearance of glutamate is likely to limit postsynaptic receptor availability through desensitization.
Finite element solution for scatterers with unbounded geometries

The class of scattering geometries that comprise a metallic cavity embedded in a perfectly conducting wedge is discussed. The absorbing boundary conditions (ABCs) approximate the behavior of outgoing waves only; consequently, these available ABCs are at a particular disadvantage when dealing with unbounded scatterers, for which the wave becomes outgoing except in the infinite limit. An additional difficulty with these scatterers is that the asymptotic behavior of their scattered field cannot be predicted a priori. To circumvent these difficulties, the combination of the surface integral equation approach with the finite element method is proposed. The versatility and validity of the surface integral equation technique are demonstrated. The bistatic and monostatic radar cross sections were calculated and found to compare favorably with results obtained using other methods. >
The basal level of intracellular calcium gates the activation of phosphoinositide 3-kinase-Akt signaling by brain-derived neurotrophic factor in cortical neurons

Brain-derived neurotrophic factor (BDNF) mediates survival and neuroplasticity through the activation of phosphoinositide 3-kinase-Akt pathway. Although previous studies suggested the roles of mitogen-activated protein kinase, phospholipase C-γ-mediated intracellular calcium ([Ca2+]i) increase, and extracellular calcium influx in regulating Akt activation, the cellular mechanisms are largely unknown. We demonstrated that sub-nanomolar BDNF significantly induced Akt activation in developing cortical neurons. The TrkB-dependent Akt phosphorylation at S473 and T308 required only phosphoinositide 3-kinase, but not phospholipase C and mitogen-activated protein kinase activity. Blocking NMDA receptors, L-type voltage-gated calcium channels, and chelating extracellular calcium by EGTA failed to block BDNF-induced Akt phosphorylation. In contrast, chelating [Ca2+]i by 1,2-bis(o-aminophenoxy)ethane-N,N,N ′,N ′-tetraacetic acid-acetoxymethyl ester (BAPTA-AM) abolished Akt phosphorylation. Interestingly, sub-nanomolar BDNF did not stimulate [Ca2+]i increase under our culture conditions. Together with that NMDA- and membrane depolarization-induced [Ca2+]i increase did not activate Akt, we conclude that the basal level of [Ca2+]i gates BDNF function. Furthermore, inhibiting calmodulin by W13 suppressed Akt phosphorylation. On the other hand, inhibition of protein phosphatase 1 by okadaic acid and tautomycin rescued Akt phosphorylation in BAPTA-AM and W13-treated neurons. We further demonstrated that the phosphorylation of phosphoinositide-dependent kinase-1 did not correlate with Akt phosphorylation at T308. Our results suggested novel roles of basal [Ca2+]i, rather than activity-induced calcium elevation, in BDNF-Akt signaling.
The maize rachis affects Aspergillus flavus spread during ear development

Aspergillus flavus that transgenically expressed the green fluorescent protein was used to follow infection in ears of maize hybrids resistant and susceptible to the fungus. Developing ears were needle-inoculated with GFP- transformed A. flavus 20 days after silk emergence, and GFP fluorescence in the pith was evaluated at 1, 2, 3, 4, 5, 10, and 20 days after inoculation. Fluorescence levels in the pith of susceptible lines were significantly higher (P < 0.0001) than in resistant lines at all time points. Pith sections apical to the inoculation point displayed higher fluorescence levels compared to other sections of the ear, suggesting fungal spread via the water/nutrient transport system. Fluorescence levels in resistant lines did not change significantly over time, implying spread of the fungus but not growth. Fluorescence in susceptible ears was highest at early time points, suggesting that conditions were more conducive to spread than at the later time points. These results suggest that the rachis could retard the spread and/or growth of the fungus inside the developing maize ear. Although fluorescence was observed in kernels from resistant ears, it occurred at a much higher frequency in those from susceptible hybrids. Together, these results suggest that the rachis is used by maize as a defense structure similar to other preformed types of resistance.
Calcinosis circumscripta in the antebrachiocarpal joint of a horse

Summary A 4-year-old, Spanish Mustang mare was evaluated because of a swelling on the dorsolateral aspect of its right carpus. The horse had no gait abnormalities. During radiographic examination of the carpus, a granular, radiopaque mass, approximately 3 cm in diameter, adjacent to the proximal row of carpal bones, was observed. The mineralised mass, which was located within the antebrachiocarpal joint, was removed through an arthrotomy with the horse anaesthetised. Histological features of the mass showed it to be overlain by partially denuded synovium, and included large deposits of mineral surrounded by multinucleated giant cells and separated by septa of mature fibrous connective tissue. These features were typical of calcinosis circumscripta. Swelling of the carpus resolved after the surgery, but the horse was lost to follow-up.