cssi/SciSciGPT-SciSciNet huggingface dataset:
Modification of leech behavior patterns by reserpine-induced amine depletion.

A single injection of 100 micrograms reserpine into the crop of the medicinal leech, Hirudo medicinalis, reduced CNS serotonin and dopamine levels to less than 1% of control values within 3 d. High-pressure liquid chromotography- (HPLC) determined CNS serotonin and dopamine levels remained maximally depressed for approximately 1 month following reserpine injection. Subsequently, amine levels recovered slowly, but remained depressed 6 months after reserpine injection. Following reserpine treatment, glyoxylic acid-induced fluorescence or neutral red staining closely mirrored the HPLC-determined time course of amine depletion and recovery. Acute exposure of isolated ganglia to 10 microM reserpine for periods up to 6 hr produced a 20–30% reduction of serotonin and dopamine content. The threshold concentration of reserpine necessary to produce amine depletion was approximately 1 microM. We found that reserpine treatment eliminated biting behavior within 4 d following injection. Biting behavior remained depressed below control levels for approximately 4 months, but returned to control values while CNS serotonin and dopamine levels remained significantly depressed at this time. Unexpectedly, reserpine treatment increased rather than reduced the duration of stimulus-evoked swimming activity. This behavioral change was evident within 3 d and persisted for approximately 3.5 months. To rapidly restore amine levels in reserpine-treated animals, we bathed intact leeches in pond water containing serotonin, dopamine, or octopamine. We found that biting behavior was restored following reserpine treatment by bathing intact leeches in pond water containing serotonin or dopamine, but not octopamine. Also contrary to expectations, the increase in swim duration was not reversed by bath exposure to serotonin, dopamine, octopamine, or histamine. However, all swimming activity in reserpine- treated leeches was eliminated by the amine antagonist cyproheptadine. We propose that the presence of low levels of amines is critical for the expression of both biting and swimming activity in leeches. However, the minimal levels of amines necessary for the expression of these behaviors are lower for swimming than for biting.
Rapid Screening Methods to Isolate Proliferation Related Compounds from Suspect Samples Utilizing Solid Phase Microextraction (SPME) Technology

The rapid field preparation of suspect samples is most important for on-site field analysis. Sample preparation is the limiting factor and becomes one of the most critical aspects of environmental monitoring. The analysis of Chemical Warfare (CW) compounds and their precursors in environmental samples are a labor intensive, time-consuming process requiring a fully equipped laboratory. Utilization of solid phase microextraction technology (SPME, Supelco Inc.) eliminates time consuming sample work-up procedures. We will discuss the advantages of utilizing SPME andin-situderivatization techniques to eliminate time-consuming steps necessary to prepare a sample for on-site gas chromatography/mass spectrometry (GC-MS) analysis. In addition, we will discuss three cases in this paper where SPME has facilitated the analysis of suspect CW samples.
An evaluation of Cray X-MP performance on vectorizable Livermore FORTRAN kernels

This paper studies the impact of the architecture features of the Cray-1 and the Cray X-MP and related compiler optimizations on machine performance. We develop a methodology for evaluating the effectiveness of the Cray Fortran compilers in coping with the architecture features and limitations of the Cray-1 and the Cray X-MP. As examples, the effects of vector register reservation and vector index misalignment on the performance of Livermore Fortran Kernels (LFKs) are presented. The causes of the performance differences of two Cray Fortran compilers, CFT1.14 and CFT77.13, on the vectorized LFKs are described and some areas for further improvement are suggested.
Dynamics of Bacterial Communities in Postharvested Eastern Oyster (Crassostrea virginica) Maintained Under Refrigeration

The selective effect that refrigeration exerts on the autochthonous microbiota of the eastern oyster was investigated using culture-independent methods. Oysters from two different locations along the Gulf Coast of Mexico were analyzed concurrently during 2-week refrigeration. Ribosomal intergenic sequence analysis (RISA) generated complex bacterial community fingerprints that provided a strong association between RISA-defined clusters and sample date. Denaturing gradient gel electrophoresis (DGGE) profiles obtained with universal primers did not reflect any association based on date or geographic origin of the samples. During the storage period, Vibrio parahaemolyticus was replaced, at least in overall abundance, with other nonpathogenic Vibrio species better adapted to cold temperatures. This study shows that refrigeration itself does not limit the growth of the bacterial community nor reduces its richness.
Nonequilibration of membrane-associated protons with the internal aqueous space in dark-maintained chloroplast thylakoids

Isolated spinach thylakoids retain a slowly equilibrating pool of protons in the dark which are predominantly bound to buffering groups, probably amines, with low pKa values. We have measured the effects of permeant buffers, salts, sucrose, and uncouplers on the retention of the proton pool. Acetic anhydride, which reacts with neutral primary amine groups, was used to determine the protonation state of the amine buffering groups. It was previously shown by Bakeret al. that the extent of inhibition of photosystem II water-oxidizing capacity by acetic anhydride and the increase in derivatization by the anhydride are proportional to, and dependent on, the deprotonated state of the amine buffering pool. Therefore, acetic anhydride inhibition of water oxidation activity may be used as a measure of the protonation state of the amine buffering pool. By this method it is inferred that protons, in a metastable state, were retained by membranes suspended in high pH buffer for several hours in the dark. When both the internal and external aqueous phases were equilibrated with pH 8.8 buffer, the proton pool was released only upon addition of a protonophore. The osmotic strength of the suspension buffer affected uncoupler-induced proton release while ionic strength had little influence. The acetic anhydride-sensitive buffering group(s) of the water-oxidizing apparatus had an apparent pKa of 7.8. We conclude that an array of protein buffering groups reside either within the membrane matrix, or in proteins at the membrane surface, not in equilibrium with the bulk aqueous phases, and is responsible for the retention of the proton pool in dark maintained chloroplasts.
Friedreich's ataxia: A neurocardiac disease

Abstract Seven cases of Friedreich's ataxia are reported, and in six of these, electrocardiograms were recorded, all of which were abnormal. A review of the literature discloses increasing awareness of the cardiac aspects of the disease. We find that in every autopsied case reported upon in the American and English literature there were abnormal findings in the heart; usually, these were findings of chronic interstitial myocarditis. We believe that Friedreich's ataxia is a neurocardiac disease which involves both the central nervous system and the heart.
Dominating sets in planar graphs

Motivated by an application to unstructured multigrid calculations, we consider the problem of asymptotically minimizing the size of dominating sets in triangulated planar graphs. Specifically, we wish to find the smallestesuch that, fornsufficiently large, everyn-vertex planar graph contains a dominating set of size at mosten.We prove that 1/4<e<1/3, and we conjecture thate=1/4.For triangulated discs we obtain a tight bound ofe=1/3.The upper bound proof yields a linear-time algorithm for finding an(n/3)-size dominating set.
Identification and characterization of a human thymus-leukemia antigen (43-kDa/513TL) bearing a structural relationship to HLA☆

Abstract A human thymus-leukemia-like antigen has been identified that is antigenically distinct from T6/HTA-1. This was accomplished with a rabbit antiserum (513) which was prepared against lymphoblasts that were E rosette negative (E−), human thymus antigen positive (HuTA+), cALLA−, DR−, SmIg− from a patient who presented with a mediastinal mass and a WBC count of 130 × 109 cells/1. Following absorption with B cell and “null” cell lines, 513 exhibited prominent reactivity with a membrane antigen that was present on normal thymocytes and lymphoblasts from 11 of 13 patients with T cell ALL and 1 of 16 patients with common ALL, but was not detected on normal peripheral blood lymphocytes, normal bone marrow cells and leukemic lymphoblasts with an undifferentiated phenotype. SDS-PAGE analysis of this antigen indicated that in was composed of two subunits, 43-kDa and 12-kDa. Sequential absorption experiments revealed that: (1) the 12-kDa subunit was antigenically similar to β2, microglobulin; (2) the intact molecule did not exhibit HLA-A, B or C “framework” determinants; (3) the molecule was antigenically distinct from a human thymus-leukemia antigen HTA-1 (recognized by monoclonal antibodies NA1/34 and OKT6); and (4) the molecule was antigenically distinct from adenosine deaminase. It is concluded that 513 reacts with a membrane protein (designated 513TL) which exhibits properties characteristic of a histocompatibility-like antigen whose expression is restricted to thymocytes and some leukemias (TL antigen). Its antigenic distinction from another recently characterized human TL antigen, HTA-1, suggests polymorphism among this family of alloantigens.
In Situ Formation of Alkylcarbonic Acids with CO2

The mutual solubility of carbon dioxide and alcohols over a wide range of temperature and pressure provides a useful and tunable medium for reactions and separations. For many years, researchers have used alcohols as cosolvents in supercritical CO2, and recently CO2-swollen alcohols have been used for antisolvent crystallization and as mobile phases for chromatography. However, little consideration has been given to chemical interaction between the alcohols and CO2. We have confirmed that such an interaction does exist and can create an acidic environment. By isolating reaction products we have demonstrated that alcohol−CO2 complexes react similarly to carboxylic acids with diazodiphenylmethane, a compound typically used to evaluate acid strengths. Our evidence indicates that the behavior of CO2−alcohol systems is comparable to that of CO2−water systems, where carbonic acid is formed.
Next generation modeling II - applications: improving the development process for eukaryotic cell cycle models with a modeling support environment

Biological pathway modelers attempt to describe cellular processes and regulatory networks with continuous and discrete models of the cell cycle. Previous practice has been to develop these models largely by hand, and then to validate models primarily by comparing time series plots versus the observed experimental results. This paper reports our experiences in designing and building a modeling support environment (MSE) for cell cycle models. We describe improvements to the development process for cell cycle models by (a) identifying the key elements of the existing modeling process, (b) applying simulation methodology to construct a revised modeling process, and (c) building and testing software that supports the revised modeling process.
Nitrogen lasing in air

We demonstrate lasing in atmospheric air from multi-photon dissociation of molecular nitrogen followed by resonant two-photon pumping of the atomic nitrogen fragments. The backwards stimulated emission provides a remote laser source for standoff detection.
Severe Left Atrial Edema and Heart Failure After Atrial Fibrillation Ablation

A 66-year-old woman with drug-refractory symptomatic paroxysmal atrial fibrillation presented for atrial fibrillation ablation. Before the procedure, she underwent a transthoracic echocardiogram and contrast-enhanced chest computed tomography (CT) scan (Figure, a) to define both her left atrial and pulmonary vein anatomy. Both structures were normal. The following day, a left atrial circumferential radiofrequency ablation throughout the atria was performed. The procedure was well tolerated, and she was discharged the …
Medullary Sponge Kidney and Medullary Nephrocalcinosis

A 40-year-old female patient came to an outpatient sonography department for a follow-up scan of calculi in the right ureter that were originally found at another medical facility. The study was ordered to see if the stones caused hydronephrosis within the right kidney. Bilaterally, echogenic renal medullae were visualized, indicating a case of medullary sponge kidney and medullary nephrocalcinosis.
Functional and biochemical characterizations of avian T lymphocyte antigens identified by monoclonal antibodies

Seven monoclonal antibodies (mAb) were used to characterize antigens present on chicken T lymphocytes and on natural killer cells by flow cytometry, radioimmunoprecipitation and by effects on cell-mediated cytotoxicity and mitogen-induced proliferation. mAb CTLA8 and 5 stained 73% of thymus, 44% of spleen and 51% of peripheral blood lymphocytes (PBL), respectively, and immunoprecipitated 65- and 45-kDa proteins from detergent extracts of 125I surface-labeled thymocytes. Pretreatment of splenic lymphocytes with mAb CTLA5 and 8 in the presence of rabbit complement (C) eliminated the concanavalin A (Con A)-induced T cell proliferative responses. mAb CTLA3, 4 and 9 stained 43% of thymus, 36% of spleen and 18% of PBL, and immunoprecipitated 33-35-kDa proteins. Pretreatment of spleen cells with mAb 4 or 9 plus C reduced, but did not eliminate, the Con A-induced proliferative response and significantly reduced both major histocompatibility complex (MHC)-restricted and non-MHC-restricted cellular cytotoxicity. mAb CTLA1 and 6 stained 58% of thymus, 13% of spleen and 19% of PBL. mAb CTLA1 and 6 immunoprecipitated a 65-kDa protein. mAb CTLA1 and 6 had no effect on the Con A-induced blastogenesis and CTLA6 caused no decrease in virus-specific cytotoxic T lymphocyte and natural killer activity. These results indicate that (a) mAb CTLA5 and 8 identify antigens on mature T lymphocytes that are similar in tissue distribution, molecular mass and function to the mammalian CD5 antigen; (b) mAb CTLA3, 4 and 9 detect the avian homologue of CD8 antigen; and (c) mAb CTLA1 and 6 identify the avian homologue of CD4 antigen.
Access to antiretroviral drugs in Brazil.

Summary Since 1996, the Brazilian Ministry of Health has guaranteed free and universal access to antiretroviral treatment for people living with HIV/AIDS. Implementation of this policy has had political, financial, and logistical challenges. I have investigated the history and context of antiretroviral policy in Brazil, the logistics of the drugs' distribution, and the government's strategies for acquisition of the drugs. Many antiretrovirals used in Brazil are produced domestically; the remainder, including some of the most expensive drugs, are purchased from abroad. Although the Brazilian policy of antiretroviral distribution has had notable success, it remains threatened by the high cost of acquisition of drugs, which has led to disputes with international pharmaceutical companies over prices and patents. Whether or not the Brazilian model of guaranteeing access to antiretroviral treatment for people living with HIV/AIDS can be applied in other countries or regions, much can be learnt from the country's experience. Published online Nov 5,2002 http://image.thelancet.com/extras/01art9038web.pdf
Strategic Defense: Catastrophic Loss of Control

What if space-based strategic defense, as proposed by the Strategic Defense Initiative (SDI), eventually works reasonably well and is deployed on both sides? This paper examines the properties of the global defensive system that could result from the interactions between the two opposing defensive systems. It is reasoned that this global defensive system could have the capacity to unintentionally and rapidly amplify relatively minor events to global catastrophe. At high states of alert, the global technological system would be difficult or impossible to control and this system could fail in a way that unintentionally initiates a catastrophic nuclear exchange. These dangers have not been adequately examined. This paper presents a framework for analyzing the catastrophic loss of control in such gllobal technological systems.
Controlling and Switching the Morphology of Micellar Nanoparticles with Enzymes

Micelles were prepared from polymer-peptide block copolymer amphiphiles containing substrates for protein kinase A, protein phosphatase-1, and matrix metalloproteinases 2 and 9. We examine reversible switching of the morphology of these micelles through a phosphorylation−dephosphorylation cycle and study peptide-sequence directed changes in morphology in response to proteolysis. Furthermore, the exceptional uniformity of these polymer-peptide particles makes them amenable to cryo-TEM reconstruction techniques lending insight into their internal structure.
Dissolution rate measurements of TiN in Ti-6242

Abstract This paper describes measurements of the dissolution rate of nitrided Ti sponge and monolithic TiN rod in molten Ti-6242. The dissolution rate is described in terms of an interface recession rate that was 2.2 μm/s for a Ti-6242 temperature of 1725°C and dissolution times between 1 and 100 min. Similar dissolution rates were measured for nitrided sponge and monolithic rod. This report also describes the microstructural and chemical interdiffusion phenomena that occur during dissolution of solid δTiN in molten Ti-6242. There is a N-containing solid αTi layer and a N-solidified βTi layer between the solid δTiN and liquid Ti-6242 during dissolution. Microprobe measurements indicate that diffusion of Al, Zr, Sn and Mo into δTiN did not occur. Steep N concentration profiles were observed in the αTi layer. Al, Zr, Sn and Mo were observed in the N-solidified βTi layer, but their concentrations were depleted with respect to Ti-6242. The N-solidified βTi layer contained
Sideband Generation In Saturated Pulsed Dye Amplifiers With Multiple Cw Single Mode Injection

The output spectral characteristics of fully saturated pulsed dye amplifiers for multimode input waves having amplitude modulation (AM) are modeled and compared with experimental measurements. The AM input in our experiments was generated by combining the outputs of two single-mode dye lasers. The spectral output of the saturated dye amplifiers consisted of the input frequencies and several sidebands spaced by the input difference or beat frequency. For our experimental system with kiton red dye amplifiers, up to 20% of the output intensity was contained in these sidebands. Sideband production was observed to decrease as the beat frequency increased with a characteristic half-width of approximately 10 GHz.
Modeling air/sea flux parameters in a coastal area: A comparative study of results from the TOGA COARE model and the NOAA Buoy model

Because estuaries and coastal regions are particularly susceptible to nutrient over-enrichment due to their close proximity to source-rich regions, a goal of the BRACE study was to improve estimates of nitrogen air/sea transfer rates in the Tampa Bay Estuary. Our objective was to critically evaluate two air/sea gas exchange models to determine their efficacy for use in a coastal region, with the ultimate goal of improving nitrogen exchange estimates in Tampa Bay. We used meteorological data and oceanographic parameters collected hourly at an instrumented tower located in Middle Tampa Bay, Florida. The data was used to determine the friction velocity and the turbulent flux of heat and moisture across the air/sea interface and then compared with modeled parameters at the same offshore site. On average both models underpredicted sensible heat flux and there was considerable scatter in the data during stable conditions, indicating that nitrogen gas exchange rates may also be underestimated. Model improvement, however, was observed with friction velocity comparisons. Model inter-comparisons of sensible heat flux and friction velocity suggest excellent agreement between the TOGA COARE and the NOAA Buoy models, but model estimated heat transfer coefficients and latent heat fluxes did not agree as well. Based on our analysis, we conclude that both models are suitable for use in a coastal environment to estimate nitrogen air/sea gas exchange, although the NOAA Buoy model requires fewer meteorological inputs. However, if the purpose is to conduct more sophisticated microscale modeling of air/sea interactions, we recommend the TOGA COARE model.
Neural activation in the “reward circuit” shows a nonlinear response to facial attractiveness

Positive behavioral responses to attractive faces have led neuroscientists to investigate underlying neural mechanisms in a "reward circuit" that includes brain regions innervated by dopamine pathways. Using male faces ranging from attractive to extremely unattractive, disfigured ones, this study is the first to demonstrate heightened responses to both rewarding and aversive faces in numerous areas of this putative reward circuit. Parametric analyses employing orthogonal linear and nonlinear regressors revealed positive nonlinear effects in anterior cingulate cortex, lateral orbital frontal cortex (LOFC), striatum (nucleus accumbens, caudate, putamen), and ventral tegmental area, in addition to replicating previously documented linear effects in medial orbital frontal cortex (MOFC) and LOFC and nonlinear effects in amygdala and MOFC. The widespread nonlinear responses are consistent with single cell recordings in animals showing responses to both rewarding and aversive stimuli, and with some human fMRI investigations of non-face stimuli. They indicate that the reward circuit does not process face valence with any simple dissociation of function across structures. Perceiver gender modulated some responses to our male faces: Women showed stronger linear effects, and men showed stronger nonlinear effects, which may have functional implications. Our discovery of nonlinear responses to attractiveness throughout the reward circuit echoes the history of amygdala research: Early work indicated a linear response to threatening stimuli, including faces; later work also revealed a nonlinear response with heightened activation to affectively salient stimuli regardless of valence. The challenge remains to determine how such dual coding influences feelings, such as pleasure and pain, and guides goal-related behavioral responses, such as approach and avoidance.
Inhibition of sigma-1 receptor reduces N-methyl-D-aspartate induced neuronal injury in methamphetamine-exposed and -naive hippocampi.

Acute and prolonged methamphetamine (METH) exposure has been reported to moderate the function of N-methyl-d-aspartate type glutamate receptors (NMDAr) in the hippocampus. These effects have been found to be associated with enhanced NMDAr-dependent release of Ca(2+) from IP(3)-sensitive intracellular stores. The present studies were designed to extend these findings and examine the role of the endoplasmic membrane (ER) bound orphan receptor, the sigma-1 receptor, in NMDA-induced neuronal injury and METH withdrawal-potentiated NMDA-induced neuronal injury. Organotypic hippocampal slice cultures were exposed to METH (0 or 100microM) for 6 days and withdrawn for 7 days, then exposed to NMDA (0 or 5microM) for 24h. Additional cultures were also exposed to this regimen and were co-incubated with BD1047 (100microM), a specific inhibitor of ER-bound sigma-1 receptors, for the 24h NMDA exposure. Cytotoxicity was assessed by analysis of propidium iodide uptake. These studies demonstrated that protracted METH exposure and withdrawal significantly potentiated the neuronal injury produced by NMDA exposure. Further, co-exposure to BD1047 with NMDA markedly attenuated neuronal injury in METH-naive and METH-withdrawn organotypic cultures. As a whole, these data demonstrate that prolonged METH exposure, even at non-toxic concentrations, significantly alters glutamate receptor signaling. Inhibition of sigma-1 receptor-dependent Ca(2+) release from the ER entirely prevented NMDA-induced toxicity in METH-naive cultures and markedly reduced METH-potentiated toxicity. These findings demonstrate the importance of Ca(2+)-induced intracellular Ca(2+) release in excitotoxic insult and suggest that blockade of glutamatergic overactivity may represent a therapeutic target in the treatment of METH withdrawal.
On the use of relaxation parameters in hybrid smoothers

The use of relaxation parameters in hybrid smoothers within algebraic multigrid (AMG) is analysed both theoretically and practically. Relaxation parameters that are optimal under the assumptions of the theory are determined. The implementation of a procedure to automatically determine outer relaxation parameters for symmetric positive definite smoothers is described. Numerical results are presented, which show significant improvements over AMG with undamped hybrid smoothers. Copyright © 2004 John Wiley & Sons, Ltd.
Spin-wave excitation in the antiferromagnetic bilayer ruthenate Ca 3 Ru 2 O 7

We study the spin-wave excitation spectrum of the antiferromagnetic bilayer ruthenate Ca${}_{3}$Ru${}_{2}$O${}_{7}$ through inelastic neutron scattering measurements. The material behaves as a quasi-two-dimensional ferromagnetic bilayer system with very weak interbilayer antiferromagnetic coupling, and its magnetic dispersion can be well described with a nearest-neighbor Heisenberg model. We find that the intrabilayer exchange interaction along the out-of-plane $c$-axis is much stronger than the in-plane intralayer interaction, in sharp contrast to the previously reported bilayer manganite system. And our study reveals a finite lifetime effect of the magnetic excitation, presumably attributable to the existence of a small number of itinerant charge carriers within the planes.
Sex Determination in Monoecious and Dioecious Plants.

Angiosperm species that produce unisexual flowers pres? ent the opportunity for separate analysis of the male and female programs for floral differentiation and gametogenesis. A vast literature describes the genetic and physio? logical basis of sex determination in these species. (For reviews, see Westergaard, 1958; Grant, 1975; Frankel and Galun, 1977; Durand and Durand, 1984.) Recently, it has become feasible to pursue the molecular genetic basis of the male and female differentiation programs in certain plant species, as has already been profitably undertaken in several animal species (Hodgkin, 1987, 1989). This article reviews the unisexual flowering schemes found in angiosperms and summarizes available data on the control of floral polymorphism in the monoecious species maize (Zea mays) and in the dioecious species mercury (Mercurialis annua).
Sex differences in social behavior and cognition: utility of sexual selection for hypothesis generation.

Knickmeyer and colleagues’ (this issue) provide intriguing evidence for a nascent and possibly hormonally influenced sex difference, favoring preschool girls, for some aspects of theory of mind (ToM), that is, skill at making inferences about the thoughts, feelings, and intentions of other people. The study is important because the measure used to assess the associated generation of mental and affective state terms and intentional propositions to describe object-to-object interactions is more sensitive to sex differences then most ToM tests used at this age. The study also contributes with the use of an evolutionary perspective to generate hypotheses regarding sex differences in ToM and social behavior. In fact, over the past three decades, Darwin’s (1871) evolutionary mechanisms of sexual selection (described below) have been used by biologists to
Stimulation of glycogenolysis in hepatocytes by angiotensin II may involve both calcium release and calcium influx

The stimulation of [3H]glucose release (a measure of glycogenolysis) from isolated guinea pig hepatocytes by Ca-mobilizing agonists can be resolved into two phases. The initial transient phase is independent of extracellular Ca, and is probably a result of Ca released from an intracellular pool. The second phase occurs only in the presence of extracellular Ca, which suggests that Ca-influx is also involved in the mechanism of Ca-mobilization by these agents in the guinea pig hepatocyte.
Preparation of isotopic molybdenum foils utilizing small quantities of material

Abstract A simple method utilizing a small amount of isotopic material for production of molybdenum foils is discussed. An e-gun is used in the procedure. The Mo powder undergoes reduction-sintering and melting-solidifying steps leading to the creation of a metallic droplet suitable for further cold rolling or vacuum deposition.
Play and Literacy Learning in a Diverse Language Pre-Kindergarten Classroom

This study explores a teacher's understandings of the role of play and her use of play in literacy learning serving children from diverse language backgrounds. The participants in this study were a public pre-kindergarten teacher and her class. Data were collected from interviews, informal conversations, observations, and self-reflexive notes. The teacher believed that play, as she defined it, has an important role in children's literacy learning and development, and she used playful activities (concrete, manipulative, fun, hands-on, and creative activities, including games) as potential teaching and learning mediums for literacy learning, within her own unique understanding and use of play. Implications for understanding multicultural and developmentally appropriate literacy practices are discussed in terms of teacher beliefs and understandings.
Chaotic Landau level mixing in classical and quantum wells.

We analyze the 3D motion of a charged particle between parallel planar potential barriers with a magnetic field applied at an angle $\ensuremath{\theta}$ to the barriers and an electric field normal to the barriers. A nonlinear map is derived for the classical system which gives analytic conditions for the occurrence of a chaotic energy exchange between the cyclotron and longitudinal motion as a function of $\ensuremath{\theta}$ and other system parameters. This energy exchange can lead to a population of very high Landau levels. Quantizing this problem suppresses energy exchange up to a critical angle determined by the localization transition.
Virus Meets Liposome

AbstractSendai virus was the first virus to encounter liposomes. Gangliosides when incorporated into liposomes act as Sendai virus receptors even at 0–4°C. When receptor-containing liposomes are incubated with virus at 37°C, they envelop the virus. At 37°C liposomes also fuse with Sendai virus membrane.Virus binding initially involves weak adhesion, which may allow the virus to “browse” the cell, and which is followed by adhesion strengthening. MicrogrΔpHs of Sendai virus fusion with liposomes after one minute at 37°C indicate that fusion occurs at the very curved leading edge of the region of the liposome enveloping virus. A model of fusion is proposed that emphasizes the role of the curvature and membrane tension in this localized region of “host” membrane. The curvature assists close approach and destabilizes the outer monolayer. The proposed intermediates are consistent with the “stalk” hypothesis.
Metabolic and genotoxic interactions of 2-ammofluorene and 2,4-diaminotoluene

Abstract We have reported previously that the rodent carcinogen 2,4-diaminotoluene (2,4-DAT) is not activated as a mutagen to the standard Ames S. typhimurium tester strains when oxidized by prostaglandin H synthase (PHS). 2,4-DAT does, however, enhance the bacterial mutagenicity of the potent mutagen 2-aminofluorene (2-AF) when both compounds are incubated with the PHS activating system. Enhancement of activation of 2-AF would provide a plausible mechanism for the observed co-mutagenicity of 2,4-DAT. Co-incubation with 100 μM 2,4-DAT, however, inhibited the total metabolism of 25 μM 2-AF by 60% in both the PHS/H2O2 system and PHS/arachidonic acid system. The inhibition included a 75% decrease in the formation of water-soluble and protein-bound metabolites and about a 35% decrease in production of the peroxidative metabolites 2-nitrofluorene (NF) and 2-aminodifluorenylamine (ADFA). Azofluorene (AzF) production was the most sensitive to the effects of 2,4-DAT, exhibiting an 80% decrease in both PHS-catalyzed systems. No new 2-AF derived products were observed in the presence of 2,4-DAT. This pronounced inhibition of 2-AF metabolism by 2,4-DAT also was observed in incubations of the aromatic amines with PHS in the presence of S. typhimurium strain TA98. Bacterial N-acetylation of 2-AF did not appear to be an important reaction in any of these incubations. 2,4-DAT not only inhibited 2-AF metabolism by PHS, but also decreased the level of 2-AF covalent binding to the bacterial DNA by as much as 81%. This stands in sharp contrast to the enhancement of the mutagenicity of 2-AF elicited by 2,4-DAT in these same incubations. This clear dissociation between the extent of peroxidative activation, and resultant covalent modification of bacterial DNA, by 2-AF and the subsequent mutagenic response indicates that a metabolic interaction is not involved in the co-mutagenicity of 2,4-DAT. © 1997 Elsevier Science Ireland Ltd.
MODIFICATION OF PHYTOPLANKTON GROWTH BY EXCRETED COMPOUNDS IN LOW‐DENSITY POPULATIONS1

SUMMARY Conditioned seawater, removed by filtration from an exponentially growing mixed phytoplankton population, inhibited the growth of a small inoculum of cells from the same source without reducing the lag period. When the 2 populations, one in exponential growth and the other freshly inoculated, were separated by a filter membrane allowing passage of excreted compounds, the growth rate of the freshly inoculated cells was again depressed but the lag phase was reduced almost as effectively as by the addition of the chelator, EDTA. Thus both inhibitory and stimulatory compounds appear to be excreted by the cells during exponential growth, the stimulatory group, apparently involved with trace metal metabolism, being more labile to degradation. A test was made to determine if the population could be induced to utilize unconditioned water. Even after repeated transfers there was no reduction in the lag period, indicating that the initiation of exponential growth represents a response to excreted conditioning agents (possibly chelating compounds) rather than an adjustment by the population to use unconditioned water.
Effect of temperature upon cell division, RNA and protein synthesis of cultured fathead minnow cells.

Abstract 1. 1. Cells of the fathead minnow cultured at 34°C grow about nine times as rapidly as at 14°C; each cell at 34°C has one-half as much total and ribosomal RNA, twice as much protein per cell and more polysomes than at 14°C. 2. 2. Double labeling with 3H-methyl methionine and 2-14C-uridine suggests DNA-like RNA is a constant fraction of the newly synthesized RNA at 14 and 34°C. 3. 3. DNA-RNA hybridization studies with nuclear and whole cell RNA show that cells at 34°C accumulate more kinds of DNA-like RNA than at 14°C. 4. 4. Cells at 34°C spend a greater percentage of their generation time in the “S” period of the cell cycle than do cells at 14°C.
Reccommendations for Conducting Real-Time Human-in-the-Loop Simulations over the Internet

Distributed simulations can improve the cognitive fidelity of simulated task environments because more operators can be added to the simulation without greatly increasing its cost. We report here on the development and execution of a distributed simulation/demonstration of ROVs flying in terminal airspace in order to investigate the feasibility of ROV flight in terminal airspace, and the feasibility of conducting simulations over the internet. The simulation involved pilots located at CSAAT, an aviation research lab at California State University Long Beach, and the Flight Deck Display Research Laboratory at NASA Ames Research Center, flying ROVs over the internet in a simulated airspace. We describe the procedures used to develop the simulation and offer recommendations for improving future simulations over the internet.
Treating patients with functional symptoms: one size does not fit all.

In an era of great advances in medicine and technology, patients, researchers, and clinicians are increasingly hopeful for “the magic bullet,” the pill that will cure our illnesses. Biomedical materialism and reductionism operate under the understanding that we can study and know the brain and its functions by dissecting its pieces to its modal parts, from behavior, to networks, to axons, to neurotransmitters and transporters, to transcription proteins, to chromosomes, to genes. The idea that drives the search for the modern panacea is that fixing the “bad genes” promises the hope that we can one day remove disease and disorders. The “bad news” is that until that hope is realized, if ever, we are stuck in clinical medicine with symptomatic treatments and few, if any, cures. Despite the “bad news,” we do have some medical “good news.” Our pharmacologic and surgical treatments are helping to prolong life and to control the sequelae of a number of major medical illnesses, such as diabetes, cardiovascular disease, and many cancers. We have amazing imaging techniques: the resolution on structural neuroimaging can now provide cuts that appear almost identical to neuropathology slides cut on the microtome. Functional neuroimaging is providing us a window into connectivity moving beyond static images, into brain physiology during cognition and affective states. As we gain insight into medical illnesses and even into the brain–behavior relationship, we are also making advances in neuropsychiatric conditions, such as dementia, movement disorders, and comorbidities of epilepsy. Despite these advances, one population that eludes our advances, however, is the somatoform population. Patients with somatoform disorders present in all medical and surgical settings, acute and chronic, with protean symptomatic manifestations [1]. Whether as globus hystericus to the otolaryngologist, or
The Factors Influencing the Plateau Characteristics of Self-Quenching Geiger-Mueller Counters

Investigations of factors influencing the starting potential and plateau slope of self-quenching G-M counters show: I. Impurities such as air or oxygen increase the plateau slope and starting potential of argon-alcohol counters. II. Operation of the counter causes changes in plateau characteristics as follows: (a) Immediately after use, the plateau slope increases slightly. (b) With continued use the plateau slope becomes steeper. (c) For moderate use the counter recovers when inactive, but never to the original characteristics. (d) With further use, the counter loses its plateau and does not recover. (e) The pressure in an argon-alcohol counter was observed to increase as a function of the total number of counts recorded. III. For argon-alcohol counters the useful life in these experiments was found to be about ${10}^{9}$-${10}^{10}$ counts; for argon-methane, ${10}^{7}$-${10}^{8}$ counts. The observed changes of characteristics are presumably due to the decomposition of the organic vapor by the discharge.
Health professional perceptions of opioid dependence among patients with pain

The purpose of this study was to determine the percentage of patients perceived by health professionals to be opioid dependent among all patients presenting with pain and specifically among sickle cell patients with pain. Surveys were completed by all staff, residents, and nurses at an urban teaching hospital with an emergency department population consisting primarily of lower socioeconomic patients of African-American origin. The surveys requested a percentage estimate of all pain patients and sickle cell patients with pain presenting to this hospital who they perceived to be opioid dependent. The estimated percentage of opioid dependent patients presenting to the emergency department with pain was 4% for staff (P < .05, n = 14), 9% for residents (n = 31), and 7% for nurses (n = 41), and the estimates for sickle cell patients presenting with pain only were 8%, 17%, and 13% respectively (P < .05). All health professional groups surveyed estimated opioid dependence in patients with pain far in excess of that shown in previous studies. It is unknown whether pain medication are withheld inappropriately by physicians who perceived patients with pain to be opioid dependent, and that this deserved further study especially among sickle cell patients.
Wavelet sampling and localization schemes for the Radon transform in two dimensions

Two theorems are presented for wavelet decompositions of the two-dimensional Radon transform. The rst theorem establishes an upper error bound in L 2 -norm between the Radon transform and its wavelet approximation whose coecients at dierent scales are estimated from Radon data acquired at corresponding sampling rates. The second theorem gives an estimate of the accuracy of a local image reconstructed from localized Radon data at multiple levels. These results show how to design a multilevel sampling and localization strategy for parallel-beam scanning by using wavelet regularity and vanishing moment characteristics, clarify the interaction between the wavelet structure and the essential bandwidth of an object image, and provide guidelines for wavelet local tomography.
Feeding of a low-zinc diet lowers the tissue concentrations of alpha-tocopherol in adult rats.

Previous work has shown that a low dietary intake of zinc for a short duration significantly lowers the lymphatic absorption of α-tocopherol (αTP) in adult male rats. The present study investigated whether the nutritional status of zinc is critical in maintaining the tissue levels of the vitamin. One group of rats was fed an AIN-93G diet containing 3 mg zinc/kg (low zinc, LZ) and the other was fed the same diet but containing 30 mg zinc/kg (adequate zinc, AZ). Food intakes between groups were matched by feeding two meals per day. At 6 wk, the body weights (356±8 g) of LZ rats reached 98% those (362±10 g) of AZ rats. Feeding of the LZ diet for 6 wk significantly lowered the concentrations of both αTP and zinc in the liver, kidney, heart, testis, and brain. No consistent relationships between αTP and zinc concentrations were observed in other tissues such as spleen, lung, gastrocnemius muscle, and retroperitoneal fat tissues. The concentrations of αTP in the liver, testis, brain, spleen, heart, and kidney were significantly correlated with the tissue concentrations of zinc. The LZ diet slightly but significantly increased the total lipid contents (mg/g) of liver, kidney, heart, and spleen. However, the tissue levels of phospholipid (µmol/100 mg lipid) in the heart, lung, testis, and spleen were decreased significantly in LZ rats. These findings indicate that low zinc intake results in a pronounced decrease in the animal’s αTP status under the conditions of matched food intakes, body weights, and feeding patterns. The lower tissue levels of αTP may explain in part the compromised antioxidant defense system and increased susceptibility to oxidative damage observed in zinc deficiency.
Drosophila immune responses as models for human immunity.

Why do insects need immune defenses? They are so small and multiply so rapidly that it is understandable to think that, although infected individuals might die, the species could survive by sheer reproductive capacity. The fallacy of this reasoning is in the numbers. Under optimal conditions, bacteria double every 20 min or so, whereas even the rapidly maturing (and favorite model) insect, the fruit fly Drosophila melanogaster, requires close to 2 wk to reproduce. If insects were unable to fight off bacterial infections, they would never survive to reproductive maturity.
‘It’s supposed to be 1863, but it’s really not’: inside the representation and communication of heritage at a pioneer village

While much heritage studies research concerns dissonance and the use of history in contemporary spaces, nuances of the narrative construction process have only more recently begun to receive attention. This paper investigates the dynamics of heritage representation, in particular the contests among park staff, which have resulted in tremendous variation in heritage narrative communication at Spring Mill Pioneer Village. Contestation among the site’s administrators and interpretative staff regarding representations of time and place in the village has resulted in inconsistencies in both the material landscape and performative storytelling. As a result, the interpretative staff use a number of narrative tactics when engaging with tourists. While the village is located within a state park and therefore has a clear hierarchical power structure, this case illustrates how dissent manifests in the actual communication of the village’s narrative. Thus, this paper contributes to the ongoing study of spatio-histori...
YouGenMap: a web platform for dynamic multi-comparative mapping and visualization of genetic maps

Comparative genetic maps are used in examination of genome organization, detection of conserved gene order, and exploration of marker order variations. YouGenMap is an open-source web tool that offers dynamic comparative mapping capability of users’ own genetic mapping between 2 or more map sets. Users’ genetic map data and optional gene annotations are uploaded, either publically or privately, as long as they follow our template which is available in several standard file formats. Data is parsed and loaded into MySQL relational database to be displayed and compared against users’ genetic maps or other public data available on YouGenMap. With the highly interactive GUIs, all public data on YouGenMap are maps available for visualization, comparison, search, filtration and download. YouGenMap web tool is available on the website (http://conifergdb.miamioh.edu/yougenmap) with the source-code repository at (http://sourceforge.net/projects/yougenmap/?source=directory).
The Nature of Interactions between Students with Severe Disabilities and Their Friends and Acquaintances without Disabilities

Children with severe disabilities and their friends without disabilities were compared with children with severe disabilities and their acquaintances without disabilities on a range of characterist...
Length and Locus of Friendship Influence Church Members' Sense of Social Support and Comfort with Sharing Emotions

ABSTRACT This study investigated whether older people involved with religious congregations differentiate their friends within the congregation from their friends outside the congregation in terms of perceptions of social support and their comfort with sharing various positive and negative emotions. The study also examined older adults' perceptions of differences in social support and comfort with sharing emotions with friends they have known a long time and friends they have known for three years or less. The results showed significant differences between long time friends and new friends in terms of a stronger sense of social support and greater comfort with sharing positive and negative emotions. No differences were noted for social support or comfort with sharing emotions in comparisons of friends within and outside of congregations. Study participants were significantly more comfortable sharing positive emotions than negative emotions with all categories of friends and there was a significant positiv...