cssi/SciSciGPT-SciSciNet huggingface dataset:
Structure, vibrational spectra, and IR intensities of polyenes from ab initio SCF calculations

Ab initio SCF calculations are presented which deal with the structure of polyenes, as model systems for polyacetylene (PA). We used a double zeta quality basis set, and determined the structure of clusters up to C22H24 as well as the vibrational spectra of clusters up to C12H14, including infrared intensities. All of these data are analyzed by comparing with experimental information available on polyacetylene and previous theoretical studies. Specifically, we identified the vibrational modes corresponding to the observed absorption bands of PA. We comment on controversial points such as the relative contributions of internal coordinates to these modes, on the magnitude of interaction force constants, and also on the effect of light polarization on the absorption of some vibrational modes. We establish that the inclusion of polarization function in the basis set does not lead to significant changes in structural or energetic properties. Convergence of the cluster properties toward the 1D polymer properties was also tested with ab initio crystal orbital calculations.Ab initio SCF calculations are presented which deal with the structure of polyenes, as model systems for polyacetylene (PA). We used a double zeta quality basis set, and determined the structure of clusters up to C22H24 as well as the vibrational spectra of clusters up to C12H14, including infrared intensities. All of these data are analyzed by comparing with experimental information available on polyacetylene and previous theoretical studies. Specifically, we identified the vibrational modes corresponding to the observed absorption bands of PA. We comment on controversial points such as the relative contributions of internal coordinates to these modes, on the magnitude of interaction force constants, and also on the effect of light polarization on the absorption of some vibrational modes. We establish that the inclusion of polarization function in the basis set does not lead to significant changes in structural or energetic properties. Convergence of the cluster properties toward the 1D polymer propertie...
Use of alternative polyadenylation sites for tissue-specific transcription of two angiotensin-converting enzyme mRNAs.

Abstract The pulmonary isozyme of rabbit angiotensin-converting enzyme (ACE) is encoded by an mRNA of about 5 kb. cDNA clones corresponding to different parts of this mRNA have been isolated and the complete nucleotide sequences of both the coding and non-coding regions of the mRNA have been determined. The encoded protein has 1309 residues with a 33 amino acids-long signal peptide at the amino terminus and a potential membrane-anchoring domain near the carboxyl terminus. There is a strong sequence homology between two regions of the rabbit cDNA and between the rabbit, human, and mouse cDNAs. Comparison of the nucleotide sequences of the 3' untranslated regions of rabbit pulmonary and testicular ACE cDNAs revealed that the testicular cDNA is nested within the pulmonary cDNA at the 3' end. A rabbit genomic clone encompassing this region was isolated and partially sequenced. It was shown that the gene contains two potential polyadenylation sites 628 bp apart within one exon. Northern analyses with an appropriate oligonucleotide probe confirmed that the proximal polyadenylation site is used exclusively for terminating the testicular mRNA whereas the distal one is used exclusively for the pulmonary mRNA. These results demonstrated that the transcription of the two mRNAs encoding the two ACE isozymes not only initiates at two alternative tissue-specific sites which are 5.7 kb apart but the mRNAs also get polyadenylated at two alternative sites which are 628 bp apart.
GENETIC COMPARISON OF ANIMAL AND HUMAN GROUP B ROTAVIRUSES USING CLONED cDNA PROBES AND TERMINAL FINGERPRINT ANALYSIS

We have recently discovered that an antigenically distinct rotavirus (group B rotavirus) is associated with gastroenteritis (GE) in rats and humans from Baltimore, MD. We now report the comparison of the genomes of the Baltimore strain of GBR (GBR-B) with the GBR strain associated with epidemic GE in China (GBR-C). GBR cDNA clones were prepared from fecal isolates of these viruses. Dot hybridizations with these cDNA clones demonstrated nucleic acid sequence homology among GBR-B, GBR-C and bovine and porcine isolates of GBR. Northern blot techniques defined specific genome segments responsible for hybridization among the GBR. We also examined the relatedness of GBR strains by means of one-dimensional (1-D) fingerprints with T1 RNase digests of genomic RNA. Conservation of terminal sequences has previously been observed between genomic segments of different strains of standard rotaviruses (group A rotavirus), and the analysis of these terminal sequences has been employed in the grouping of rotavirus strains. 1-D fingerprints of GBR strains indicated variability rather than conservation in the sequences at the ends of gene segments obtained from individual GBR. These studies document the relatedness of GBR strains from different animal species and geographic locations. We also find that GBR are not just antigenically and genetically distinct from group A rotaviruses: GBR display structural differences in their terminal genomic sequences not noted with GAR.
Extraction of parasitics in GaN HEMTs via Full-Wave Electromagnetic Modeling

We present a new equivalent circuit model for millimeter-wave and sub-millimeter wave GaN high electron mobility transistors (HEMTs) that can capture the geometry-and material-dependent parasitic effects within the device. The impact of electromagnetic interactions on overall device performance is analyzed extensively via full-wave EM simulations using high-fidelity device geometries. An empirical lumped-element equivalent circuit model is developed to capture the electromagnetic behavior not only within the internal structure of the device but also the surrounding impedance environment. Based on this parasitic-aware equivalent circuit, a multiple-step parameter extraction algorithm is employed to determine the equivalent lumped elements. Numerical results, using a conventional sub-mmW HEMT topology are presented to illustrate the performance of the proposed circuit models in capturing device physics in the THz band.
Latino expectations of communicative competence: A focus group interview study

Drawing on Martin, Hammer, and Bradford's (1994) work on intercultural communicative competence, this investigation explored Latino expectations of communicative competence using focus group interviews. Like the Martin et al. (1994) study, communicative competence was examined in four contexts — intracultural‐social, intracultural‐task, intercultural‐social, and intercultural‐task. Results indicated overall support for seven of Martin et al.’s (1994) eight behavioral categories. Data from focus group interviews in this study suggested an additional competence category specific to task contexts as well as some emic behaviors not identified in the Martin et al. (1994) investigation.
Personal Influences on Professional Work: An Empirical Case Study of B. F. Skinner

This study addresses the hypothesis that individuals have characteristic ways of looking at the world that are revealed not only in their life story but also in their professional work. It seeks to provide the first empirical test of this hypothesis using systematic methods for data selection, interpretation, and matching, as applied to the case of B. F. Skinner. Using the salience identifier "primacy" (Alexander, 1990), Skinner's first research design and the first paragraph of his autobiography were selected for analysis. Adopting a personological approach to interpretation, "scripts" (Tomkins, 1987) were derived from these materials by blind and independent coders. A matching task (Allport, 1961) then indicated that the scripts derived from Skinner's work and life were substantially similar and significantly more similar than random pairs of scripts . A search through other autobiographical and professional writings by Skinner revealed that the elements of the discovered script appear recurrently in his imagery.
Investigation of Yo* (1405) production by K− at rest in emulsion

Emulsion stocks were exposed to a K/sup -/ beam from the Bevatron. Momentum and mass distributions obtained in analysis of the events gave no evidence for a previously reported SIGMA - pi resonant state in C/sup 12/ at 1405 Mev with a width of 1 Mev. The SIGMA - pi nnass spectrum for K/sup -/ on C/sup 12/ showed an enhancement around 1412 Mev, but impulse model calcuplease delete the above abstract no. 29542-------
Porosity and Lithologic Estimation Using Rock Physics and Multiattribute Transforms In The Balcon Field, Colombia - South America.

Summary This study presents the results of combining rock physics, seismic inversion and multiattributes transforms to estimate rock reservoir properties of Cretaceous aged sandstones deposited in a fluvial-deltaic environment (Caballos Formation) from The Balcon Field. This study, which developed out of a need to better understand the significance of seismic amplitude variations at the reservoir level and their relationship with rock properties, determined that acoustic related seismic attributes (velocity and acoustic impedance) are sensitive to changes in rock porosity and lithology. In spite of the high scatter observed in the cross-plots, due to factors such as composition, clay content, diagenesis and texture of the rock, two main rock physics trends are recognized. Thus, the lower stratigraphic unit, which is composed of poorly sorted dirty sandstones deposited in a fluvial environment with high clay content, has higher velocity and lower porosity than the upper stratigraphic unit, which is composed of well-sorted and clean deltaic sandstones. Cross-plots also indicate that the porosity-velocity and porosity-acoustic impedance relation are greatly improved when stratigraphic constraints are used. It is demonstrated that the acoustic impedance attribute derived from model-based inversion can be used as the main seismic attribute to estimate spatial distribution of rock properties in the Balcon Field. If this attribute is combined with other seismic attributes in linear or non-linear mode, the match between well-attribute log derived properties (Porosity and Gamma Ray log) and the predicted values is improved to a great extent.
The State of Scholarly Journal Publishing: 1981-2000

Scholarly journals play a substantive role in the dissemination of knowledge among academics, and university presses have been exceptionally active as journal publishers. But since 1981 a series of events has affected, and in some instance adversely affected, journal publishing. This article analyses data from the Institute for Scientific Information (ISI) regarding 1317 scholarly journals in 25 marker fields and addresses the following question: It has been alleged that it became difficult for academics in certain fields to get published in scholarly journals. Was there any decrease in the number of articles published in the 1317 journals analysed in this study? Other questions addressed in this paper include the following: What impact did the serials crisis have on university presses? Did the economics of journal publishing change between 1981 and 2000? What is the potential impact of the 'open access' movement on scholarly communication?
Physicochemical Characterization and Membrane Binding Properties of Camptothecin

ABSTRACT The intrinsic solubility of the CPT-lactone free base in acidic pH was determined to be 3.44 and 5.11 µM at 22 and 37°C, respectively. The equilibrium solubility of the drug was found to increase with increasing temperature and decreasing pH. The enhanced solubility of the drug at very low pH is attributed to the protonation of the nitrogen atom in the ring B and the increased solvency of the highly concentrated acidic media. The logarithmic value of the intrinsic partition coefficient P of the free base CPT-lactone form was estimated to be 1.65, characteristic of a molecule suitable for absorption. Association constants K f of the drug for bilayers composed of the zwitterionic (DOPC) and the negatively charged (DOPG) were determined at acidic pH by fluorescence anisotropy to be 35.4 ± 4.5 M −1 and 93.1 ± 11.0 M −1 , respectively, indicative of the CPT tendency to preferentially bind to negatively charged membranes. The results indicate that at highly acidic media, CPT is positively charged and exists at its stable lactone form of increased solubility and capacity to bind to negatively charged membranes. These features could be used to invent novel formulation strategies to optimize the antitumor activity of CPT. © 2008 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 97:4379–4390, 2008
IL‐15 acts as a potent inducer of CD4+CD25hi cells expressing FOXP3

IL-15 is a member of the gamma chain-dependent cytokines and known to affect innate and CD8(+) adaptive immune responses. Despite a growing interest in the use of IL-15 as an immunotherapeutic agent, the broad spectrum of immunoregulatory functions exerted by IL-15 has not been fully elucidated. Here, we demonstrate that IL-15 increases expression of CD25 and forkhead box transcription factor P3 (FOXP3), a master transcriptional regulator of regulatory T cells, in human peripheral CD4(+)CD25(-) T cells in the absence of antigenic stimulation. Comparisons involving IL-2 and IL-7 revealed that the induction of CD25(hi) and FOXP3 expression was most prominent with IL-15 and IL-2. More modest effects were seen with IL-7. Despite levels of FOXP3 expression comparable to that of conventional regulatory T cells, cytokine-induced CD4(+)CD25(hi)FOXP3(+) cells exerted only weak suppressor activity. Thus, the current study has demonstrated that IL-15 acts as a potent inducer of CD4(+)CD25(hi)FOXP3(+) cells in the periphery, and suggests a potential role for IL-15 in blunting immune activation. This study has provided further insights into the pleiotropic nature of IL-15 beyond the regulation of CD8(+) T cells.
Chertification in the Mississippian Lake Valley Formation, Sacramento Mountains, New Mexico

Chert distribution in the Lake Valley rocks is selective to mud-supported facies; it is not related to proximity to unconformities. The facies selectivity of the chertification is believed to be a function of the depositional distribution of indigenous silica as sponge spicules, an interpretation that is supported by high positive qualitative correlation of chert with spiculitic rocks. Petrography indicates that the spicules were all originally siliceous, and that they all went through a moldic stage during which many molds were compactively destroyed and distorted. Remaining molds were subsequently cemented by calcite or chalcedony. Chert distribution and spicule petrography argue for an intraformational source for much of the silica. Chert micro-fabrics are dominated by microquartz, a replacement of grains and lime mud; length-fast chalcedony, a pore-filling cement; and megaquartz, a post-chalcedony pore-filling cement. Petrography of compaction features within chert masses indicates that chertification occurred after some burial. Based on stratigraphic reconstruction this burial depth was a maximum of about 215 m. and was most likely a few metres to a few tens of metres. Petrography of chert-calcite cement relationships indicates that chertification occurred before and during first generation, pre-Pennsylvanian non-ferroan calcite cementation, and was completed before late-stage, post-Mississippian ferroan calcite precipitation. Petrography of chert clasts in basal Rancheria (Meramecian) and basal Pennsylvanian conglomerates proves these clasts derived from the Lake Valley Formation and were chertified before redeposition. Thus, some cherts in the Lake Valley are pre-Meramecian in age, but all are pre-Pennsylvanian in age. Furthermore, association of the cherts with the non-ferroan cements indicates the cherts were probably precipitated in meteoric phreatic lens established beneath the pre-Meramecian and pre-Pennsylvanian subaerial unconformities.
Electromagnetic response of a dipping anisotropic half-space

An idealized two-dimensional anisotropic half-space model for the earth is adopted. The axis of the conductivity tensor is inclined at an arbitrary angle with respect to the air-earth interface. The surface impedance is analyzed for the case where the sole component of the magnetic field is parallel to the strike (the direction of a line formed by the intersect of a stratum with a horizontal plane) of the structure. The incident field is allowed to vary in the direction perpendicular to the strike rather than being invariant as in previous analyses. It is indicated that the surface impedance is a diagnostic of the degree of anisotropy and the tilt or dip angle of the striations. >
Adaptive Functions of Nymphal Aggregation in the Southern Green Stink Bug, Nezara viridula (L.) (Hemiptera: Pentatomidae)

The role of aggregation in mediating the ecological parameters that influence survival and development in first-instar southern green stink bug, Nezara viridula (L.), was examined. Aggregated nymphs were able to survive and develop more rapidly than isolated nymphs at low relative humidities. Aggregation appeared to facilitate intake of atmospheric water and protect against desiccation. An acceleration of development in aggregated nymphs was observed at low temperatures. It was confirmed that first instars do not feed, so aggregation had no role in nutrient intake. Aggregation apparently does not function as a means of contacting essential symbiotes. Adherence to a substrate was facilitated by aggregations of up to 10 nymphs, at which point aggregation became multilayered. Aggregated nymphs suffered less predation by Podisus maculiventris (Say) and Solenopsis invicta Buren. Individuals as well as groups of nymphs were unpalatable to Hippodamia convergens Guerin-Meneville. Monomorium minimum (Buckley) apparently learned nonpreference of first instars while Tertamorium guineense (F.) and Pheidole dentatum Mayr were undeterred from foraging for nymphs over time.
Effect of blend composition on diffusivity and solubility of small molecules in polystyrene/poly(vinyl methyl ether) blends

The capillary column inverse gas chromatography technique was used to determine diffusivity and solubility data for several solvents in polymer blends composed of polystyrene and poly(vinyl methyl ether) (PVME). Diffusivity behaved as expected, increasing as the concentration of PVME increased in the blend. Knowing only the free-volume parameters for the pure polymers, the free-volume theory was successfully applied to predict the dependence of the diffusion coefficients on the blend composition. Transport in blends above the glass transition temperature is controlled by free volume, and the effect of concentration fluctuations is minimal at the temperatures studied. Experimental data show an increase in the partition coefficient of some solvents in the blends with respect to the pure polymers. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2071–2082, 2007
Update in infectious diseases.

This Update covers the management of hepatitis C, the current state of antibiotic resistance, prevalent infections, less common infectious disorders, and novel treatment approaches.
Gamow-Teller electron capture strength distributions in stars: Unblocked iron and nickel isotopes

Abstract Results of shell-model calculations of the Gamow-Teller strength distributions for the (n, p) or electron capture direction are presented for 54 Fe → 54 Mn, 56 Fe → 56 Mn, 56 Ni → 56 Co, 60 Fe → 60 Mn, and 64 Fe → 64 Mn . In the cases of 56Fe, 60Fe, and 64Fe calculations were performed on both the ground and first excited states. These and similar transitions are characterized by large amounts of Gamow-Teller strength at low excitation energy in the daughter nuclei. The question of quenching in the (n, p) direction remains open. It is expected that the late stages of presupernova stellar evolution (before neutron shell blocking) will depend on the character and distribution of Gamow-Teller strengths for electron capture transitions such as these.
Permeability of bacterial cellulose membranes

Abstract Mass transfer experiments were conducted to determine the transport and interaction parameters of selected molecules in hydrated bacterial cellulose (BC) membranes. The objective was to determine physiochemical characteristics and elucidate the mechanisms governing transport in relation to the membrane structure. Pore and sorption models developed previously for the analysis of transport in hydrogel membranes were relevant to the cellulose membrane system, including: (1) interfacial phenomena between the bulk fluid and the outer membrane surfaces and/or along a pore wall, (2) sorption into the membrane matrix itself with diffusion possibly affected by immobilization at specific interactive sites, (3) free and/or fixed site diffusion within the matrix and if appropriate, through the porous regions, whether as distinct pores, micro-channels or other non-homogeneous/discrete areas and (4) chemical reactions that could alter the nature of the diffusing species or the media itself. Since all these mechanisms may be active, our classification, and thus characterization, was based upon whichever mechanism dominates. The diffusion coefficients of various dextrans (44–260 kDa), measured using a horizontal flow diffusion chamber, were compared to their corresponding values in water to demonstrate hindered diffusion. The degree of hindrance, ψ, was the same for all four dextrans indicating that the parameter is not a function of pore or micro-channel size but rather due to the presence of membrane fibers. Three representative marker molecules (Vitamin B12, lysozyme and bovine serum albumin) were evaluated using the same apparatus combined with desorption experiments to measure permeation (P) and effective diffusion (Deff) coefficients. Partition coefficients, H, were subsequently calculated and verified experimentally. Estimates of Deff in the BC membranes were made through a weighted average using literature values for the diffusion of the three molecules in water and regenerated cellulose along with measured H and ψ values. The experimental results are in excellent agreement with these estimates indicating the presence of dual transport mechanisms, for solute transport through the continuous water phase and cellulose matrix, with some hindrance of molecular diffusion via fiber obstruction. With Vitamin B12 and lysozyme (the two smallest solutes), equilibrium interactions such as adsorption and solubility are also important. These results help clarify the potential utility of these novel bio-derived membranes in a variety of possible separations scenarios.
Analysis of acrolein and acrylonitrile in aqueous solution by membrane introduction mass spectrometry

Acrolein and acrylonitrile can be quantified directly at low levels in aqueous solution using membrane introduction mass spectrometry. Electron impact was used to generate positively charged ions and electron capture of the O-(2,3,4,5,6-pentafluorobenzyl)hydroxyl amine (PFBOA) derivative was used to generate negatively charged ions of acrolein in aqueous solutions. The origins of all ions in the mass spectra and product MS/MS spectra recorded using both ionization methods were assigned and a reaction scheme is given which accounts for the fragmentation of the PFBOA derivative. Detection limits were measured using multiple reaction monitoring in both the methods. With electron capture detection, acrolein could be detected without preconcentration at 10 ppb levels. Electron impact ionization and multiple reaction monitoring both allowed the measurement of acrylonitrile at levels as low as 10 ppb.
South Atlantic intermediate water mass geometry for the last glacial maximum from foraminiferal Cd/Ca

[1] Paleoceanographic studies using benthic foraminiferal Cd as a nutrient tracer have provided a robust means of reconstructing glacial Atlantic Ocean water mass geometry, but a paucity of data from the South Atlantic above 1200 m has limited investigation of Antarctic Intermediate Water (AAIW) configuration and formation. A new Cd depth profile from Brazil margin sediments suggests that AAIW penetrated northward at 1100 m to at least 27°S in the glacial Atlantic. It exhibited substantially reduced δ13Cas values, confirming preliminary evidence that this AAIW was unique to the glacial Atlantic and that it formed differently than today, with less atmospheric contact.
Surrogate markers in AIDS research. Is there truth in numbers

MATHEMATICAL models and statistical evaluations are often used to explain biologic phenomena. The acquired immunodeficiency syndrome (AIDS) is no exception. Through the years of studying the human immunodeficiency virus (HIV) and its effect on the immune system, investigators have emphasized counting CD4 + cells and CD8 + cells and/or measuring p24 antigen levels or, more recently, the viral RNA content of the plasma. What is known, but not always appreciated, is the limited information that may be reflected by these parameters when measured in the blood. Peripheral blood lymphocyte numbers represent only a small percentage (3%) of the total white blood cells in the body, 1 and plasma virion content is just a portion of the total HIV virions, which are concentrated primarily in lymphoid organs. 2 Thus, in several experimental systems, plasma viral RNA may not reflect the actual viral load. Moreover, although CD4 + cell numbers may be helpful in predicting
The Effect of Transpiration on the Absorption of Salts by Plants

Various opinions have been offered regarding the relation between transpiration and the absorption of solutes. Those investigators who support the older theory maintain that the quantity of salts taken into a plant is directly proportional to the amount of water transpired, and that the quantity of water transpired is in inverse ratio to the concentration of the solution. Some workers maintain that there is no direct relation between transpiration and the absorption of salts. In other words, the rate at which salts enter the cell is independent of the rate at which water enters the cell. Others accept the theory that the water and solutes of a solution enter a plant at independent rates, but maintain that after the solutes enter the plant they move along with the water in the "transpiration stream. " A large amount of literature has appeared dealing with transpiration and water requirements,, but, with few exceptions, no papers have appeared which offer any considerable data on a possible relation between transpiration and the intake of solutes. In spite of this fact, many authors have not hesitated to employ various theories regarding the relation between transpiration and the absorption of salts in explaining results which they have obtained in investigations upon transpiration and water requirements. The fact still stands, however, that a careful search through the literature reveals no conclusive data which would substantiate the correctness of any of these theories. From 4 theoretical standpoint it would be reasonable to assume that the entrance of water and solutes into the plant takes place independently, since they enter not through openings which would allow for mass flow but through membranes which necessitate diffusion. Actual data presented are conflicting. The writer has been carrying on a ntumber of experiments with reference to a possible relation between transpiration and the absorption and distribution of salts in plants. The results obtained in those experiments bearing on absorption only are reported in this paper.
Soil-washing technology and practice

Soil washing in the United States has been studied and evaluated with increasing thoroughness during the last 15 to 20 years. It is now entering a phase of actual use and acceptance as its applicability and economics become clearer. This paper reviews the principles behind soil washing, methods of predicting and measuring its performance, some typical soil-washing processes, and several recent field applications
Distribution of immunophilin FKBP-12 protein and mRNA within the mammalian cochlea and cochlear nucleus

Abstract Immunophilin FK binding protein-12 (FKBP-12), the soluble receptor for the immunosuppressant drug FK506, is involved in a number of neuronal activities including increased nerve regeneration in the peripheral nervous system and enhanced recovery in animal models of neurodegenerative diseases. In addition, FKBP-12 is tightly bound to the calcium release channel ryanodine receptor and physiologically interacts with the inositol 1,4,5-trisphosphate receptor. In nearly all cell types, release of intracellular Ca2+ and subsequent second messenger signaling involves activation of these ion channels. We determined the distribution of FKBP-12 within the mammalian cochlea and dorsal cochlear nucleus (DCN) in order to gain insight into Ca2+ regulation within the cochlea and to possibly identify potential cellular targets for neuroimmunophilin ligands that may prove useful in protection and recovery following ototoxic insult. FKBP-12 protein and mRNA were found to be abundant throughout rat and guinea pig cochlea and DCN.
Indirectly primed CD8+ T cells are a prominent component of the allogeneic T-cell repertoire after skin graft rejection in mice.

Background, Alloreactive CD4 and CD8 T lymphocytes recognize antigen through both the direct and the indirect pathways. Although indirect priming of CD4 + T cells has been well described, little is known about the frequency and cytokine profile of indirectly primed CD8 + T cells during fully allogeneic graft rejection. Methods. We used a cytokine enzyme-linked immunosorbent spot assay to characterize indirect priming of alloreactive CD8 and CD4 cells in mice. Results. Interferon-y-producing CD8 + T cells specific for indirectly presented alloantigen were detectable in allograft-primed mice at a frequency of 50-100 per million cells (compared with 3000 per million for responses through the direct pathway) and were similar in frequency to indirectly primed CD4 cells. Conclusion. CD8 + T cells primed through the indirect pathway are a prominent component of the alloreactive T-cell repertoire induced after skin graft placement in mice, raising the possibility that these cells may play a significant role in the rejection process itself.
Selective water uptake within micelle-containing layer-by-layer films of various architectures: a neutron reflectometry study

Swelling of micelle-containing layer-by-layer (LbL) films of various architectures has been studied by neutron reflectometry (NR). Multilayers of the first type were constructed using poly(2-(dimethylamino)ethyl methacrylate)-block-poly(N-isopropylacrylamide) (PNIPAM-b-PDMA) block copolymer micelles (BCMs) alternately assembled with poly(4-styrene sulfonate) (PSS). NR data showed that the films maintained their layered structure, but deuterated PSS (dPSS), deposited within every 5th layer as a marker, was highly interdiffused into neighboring layers. In situ NR measurements demonstrated that the films swelled homogeneously by ∼35% in an aqueous environment. The second type of multilayer contained three zones: bottom and top stacks consisting of PDMA/dPSS homopolymer assemblies, and BCMs deposited in the middle stack as (BCM/dPSS)n, where n is the number of deposition cycles, equal to 1 or 2. The individual micellar layer deposited in a single deposition step (n = 1) only partially covered the surface, whereas a complete layer of micelles was achieved after two deposition cycles. In situ NR study of these stacked films revealed different degrees of water uptake by film internal strata. While layers of assembled micelles took up ∼38% water by volume when dry films were exposed to an aqueous environment at 25 °C, the bottom homopolymer stack was able to take up only 11–20% water. In addition, the film architecture and the degree of surface coverage by BCMs were found to be important factors enabling the study of selective swelling of film strata. NR-enabled observations of selective swelling of assembled amphiphilic BCMs allow one to correlate film swelling on the nanoscale with internal structure, and present a powerful approach for future studies of BCM-containing systems, which are useful in actuation, sensing, and controlled delivery applications.
Pharmacodynamics must inform statistics: an example from a cocaine dependence pharmacotherapy trial.

Background. There is no FDA-approved medication for cocaine dependence or consensus on the statistical approach for analyzing data from cocaine dependence pharmacotherapy trials. The goal of this paper is to illustrate the importance of understanding medication’s pharmacodynamics when specifying the statistical model to test its efficacy. Method. Data from a double-blind placebo controlled trial of reserpine for cocaine dependence are analyzed. Since the antihypertensive properties of reserpine are well established, blood pressure data are utilized to evaluate the ability of two statistical models, one that does not take the pharmacodynamics of reserpine into account and one that does, to detect reserpine’s antihypertensive effect. Results. The statistical model specified without regard to reserpine’s pharmacodynamics failed to find a significant medication effect for either systolic () or diastolic () blood pressure. Contrariwise, the model based on the pharmacodynamics of reserpine found a significant effect for both systolic () and diastolic () blood pressure. Conclusions. If the pharmacodynamics of a study medication are not considered when specifying statistical models, then erroneous conclusions may be reached. This trial is registered with NCT00033033.
Is erythropoietin the only factor which regulates late erythroid differentiation

Haematopoiesis is a useful model system for studying differentiation and the regulation of precursor cell populations intermediate between the multipotential stem cell and terminally differentiated end cells. For many years, erythropoietin (Epo) was recognized as the hormone which controls red cell production in vivo. Although other substances are now known to be required during the initial stages of erythropoiesis, late erythroid differentiation is regarded as strictly Epo-dependent. This concept is supported by the recent demonstration that the addition of Epo alone to serum-free bone marrow cell cultures is sufficient to stimulate the CFU-E (colony-forming unit-erythroid-a late erythroid precursor cell approximating to a proerythroblast) to complete differentiation into mature erythrocytes. However, the data reported here indicate that mature erythroid colonies (indistinguishable from those formed by CFU-E + Epo) are formed when adult bone marrow cells are grown for 2 d in methyl cellulose cultures containing spleen cell-conditioned medium (SCM) but no added EPO. SCM is a rich source of growth factors and initial observations suggested that its 'Epo-like' activity could be attributed to: (1) Epo, or (2) a factor which enhances the activity of small amounts of Epo in the culture medium, or (3) a factor(s) distinct from Epo which is also capable of stimulating late erythroid differentiation. The experiments reported here, which include a partial characterization of the 'Epo-like' activity, support the latter interpretation.
Self-referential gestures in conversation

One way speakers can refer to themselves in conversation is with a stressed first-person pronoun accompanied by a movement of the hand to or toward the chest. This can be produced alone or in tandem with a reference and gesture to another person. Close analysis of several instances of self-referential gesture demonstrates that this form of self-reference is designed to achieve interactional work beyond simple reference, specifically relational disaggregation and self-referential extraction.
Germline transcription from T-cell receptor Vβ gene is uncoupled from allelic exclusion

Allelic exclusion operates in B and T lymphocytes to ensure clonal expression of antigen receptors after V(D)J recombination. Germline transcription, which proceeds V(D)J recombination, has been postulated to provide an instructive signal for allelic exclusion. Here, we use a genetic marker to track germline transcription from a Vβ gene within the TCRβ locus. We find that developing thymocytes exhibit uniformed, bi-allelic activation of the Vβ gene before V-DJ recombination, a process subject to allelic exclusion. We further show that V-DJ rearrangement promotes activation rather than silencing of germline transcription from the remaining Vβ genes on either the functionally or non-functionally rearranged chromosome. Results presented here suggest that germline transcription, although necessary for V(D)J recombination, is not sufficient to instruct allelic exclusion.
Stimulus suffix effects in recognition memory.

Recall of auditory items can be disrupted by presentation of an irrelevant auditory stimulus (a stimulus suffix). Previous researchers have suggested that suffix effects are not found on recognition tests. Two experiments are presented here that demonstrate suffix effects on recognition tests. These results suggest that suffixes interfere with item information and that suffix effects cannot be attributed solely to retrieval processes.
Treating method and form as phenomena: An appreciation of Garfinkel's phenomenology of social action

In the beginning is the deed.. . We wish, then, to consider the surrounding lifeworld concretely, in its neglected relativity. . .the world in which we live intuitively. . .with its real entities. . .as they give themselves to us at first in straightforward experience . . .Our exclusive task shall be to comprehend precisely.. .this whole merely subjective and apparently incomprehensible 'Heraclitean flux.' ? Edmund Husserl, The Crisis of European Sciences and Transcendental Philosophy
Temporal Patterns of Happiness and Information in a Global Social Network: Hedonometrics and Twitter

Individual happiness is a fundamental societal metric. Normally measured through self-report, happiness has often been indirectly characterized and overshadowed by more readily quantifiable economic indicators such as gross domestic product. Here, we examine expressions made on the online, global microblog and social networking service Twitter, uncovering and explaining temporal variations in happiness and information levels over timescales ranging from hours to years. Our data set comprises over 46 billion words contained in nearly 4.6 billion expressions posted over a 33 month span by over 63 million unique users. In measuring happiness, we construct a tunable, real-time, remote-sensing, and non-invasive, text-based hedonometer. In building our metric, made available with this paper, we conducted a survey to obtain happiness evaluations of over 10,000 individual words, representing a tenfold size improvement over similar existing word sets. Rather than being ad hoc, our word list is chosen solely by frequency of usage, and we show how a highly robust and tunable metric can be constructed and defended.
Effects of Long versus Short Bout Exercise on Fitness and Weight Loss in Overweight Females

Objective: The specific aim of this study was to determine if three 10 minute bouts of exercise per day (3 × 10) and two 15 minute bouts per day (2 × 15) were as effective as one 30 minute bout per day (1 × 30) for improving VO2 max and weight loss.Methods: Overweight, female college students (body mass index ≥28 kg/m2) were recruited and assessed at baseline and post-treatment for aerobic fitness (Astrand maximal cycle test), weight, skinfold thickness (7-site), and circumference measures (4-site). Following measurement of resting energy expenditure (REE), subjects were asked to follow a self-monitored calorie restricted diet (80% of REE) for the twelve week duration of the study and were assigned (non-random) to one of four treatment groups: 1) a nonexercising control group (control, n = 8), 2) a 30 minutes continuous exercise group (1 × 30, n = 12), 3) a 30 minutes accumulated exercise group (2 × 15, n = 10) and 4) a second 30 minutes accumulated exercise group (3 × 10, n = 8). The exercising subjects ...
Electron emission from ferroelectric ceramics

The results of experiments on the emission of electrons from ferroelectrics are reported. A sample of PZT is pulsed to reverse the direction of the spontaneous polarization within the material. This releases the surface charge accumulated on the ferroelectric, which is needed to reduce the external electric field to a low value. Surface charge densities may amount to about 0.5 C/m/sup 2/. In these experiments, the emitted electron current density reaches a peak value of up to 70 A/cm/sup 2/ for a diode gap of 4 mm and an extraction voltage of 500 V. Beam current densities exceed the Child-Langmuir law for space-charge-limited emission by factors of up to 400. Measurements showing the dependence of the emission on the diode voltage and spacing are presented. The authors' understanding of the emission process and its limitations are summarized. >
HERG potassium channel regulation by the N-terminal eag domain

Human ether-a-go-go related gene (hERG, Kv11.1) potassium channels play a significant role in cardiac excitability. Like other Kv channels, hERG is activated by membrane voltage; however, distinct from other Kv channels, hERG channels have unusually slow kinetics of closing (deactivation). The mechanism for slow deactivation involves an N-terminal “eag domain” which comprises a PAS (Per-Arnt-Sim) domain and a short Cap domain. Here we review recent advances in understanding how the eag domain regulates deactivation, including several new Nuclear Magnetic Resonance (NMR) solution structures of the eag domain, and evidence showing that the eag domain makes a direct interaction with the C-terminal C-linker and Cyclic Nucleotide-Binding Homology Domain.
LVis-digital library visualizer

LVis (Library Visualizer) is a joint project aimed at the 2D and 3D visualization of search results derived from user queries of digital library collections. This paper gives an overview of the intent of the project, the data mining techniques applied, the visualization metaphors used and the usability studies that have been planned and undertaken to date.
Detecting critical nodes in sparse graphs

Identifying critical nodes in a graph is important to understand the structural characteristics and the connectivity properties of the network. In this paper, we focus on detecting critical nodes, or nodes whose deletion results in the minimum pair-wise connectivity among the remaining nodes. This problem, known as the critical node problem has applications in several fields including biomedicine, telecommunications, and military strategic planning. We show that the recognition version of the problem is NP-complete and derive a mathematical formulation based on integer linear programming. In addition, we propose a heuristic for the problem which exploits the combinatorial structure of the graph. The heuristic is then enhanced by the application of a local improvement method. A computational study is presented in which we apply the integer programming formulation and the heuristic to real and randomly generated data sets. For all instances tested, the heuristic is able to efficiently provide optimal solutions in a fraction of the time required by a commercial software package.
RFID as a disruptive innovation

The first part of the paper discusses Wal-Mart's adoption of RFID through the theoretical lens of the Resources, Processes, and Values (RPV) innovation theory. This part makes a theoretical argument that Wal-Mart adopted RFID as a sustaining innovation - an incremental improvement in supply chain identification technology. The second part reviews a representative sample of IS literature in order to investigate whether IS researchers have been influenced by Wal-Mart's perspective on RFID. The literature review suggests that many IS researchers have also adopted Wal-Mart's perspective on RFID. The third part argues that RFID technology has a potential to become a disruptive technology with a profound impact on business and society. Given this possibility, both researchers and practitioners are provided with two frameworks ("object oriented approach" and "visionary approach") which can help them to adopt a more forward-looking perspective in relation to RFID. The object oriented approach starts from the basic capabilities offered by RFID technology and attempts to determine how these capabilities can be used to create a new RFID application. The visionary approach starts by assuming that RFID technology has reached its peak in terms of breadth of adoption and then tries to determine opportunities offered in this situation.
A role for vertebral biopsy in selected patients with known malignancy. A report of three cases.

S keletal metastases commonly occur in the spine1-4 and present at multiple levels in as many as 40% to 70% of patients who have disseminated malignant tumors5-7. Skeletal metastases most commonly arise from breast, lung, prostate, colorectal, and renal primary tumors as well as from lymphoreticular tumors, such as lymphoma or multiple myeloma8-12. Lesions that are metastatic to the spine represent the first manifestation of cancer in as many as 20% of symptomatic patients13,14. Overall, approximately 10% of patients with neoplastic disease are likely to have clinically important symptoms resulting from secondary lesions of the spine3,15-17. With the advent of modern imaging modalities such as magnetic resonance imaging, computed tomography, and bone scanning, asymptomatic lesions of the spinal column are now more frequently identified during the follow-up surveillance of patients with malignant tumors18,19. An accurate diagnosis is essential for appropriate staging and management of any tumor, but it is common for clinicians to institute palliative care for patients who have a known malignant lesion on the basis of the probability that the newly identified lesion represents metastasis from the original primary malignant lesion. There are few clinical data available from which to accurately estimate the prevalence of a second primary malignant lesion in the presence of existing neoplastic disease. We report on three patients with preexisting malignant disease who presented with new lesions of the spine and in whom the presumptive diagnosis of metastasis or recurrence proved to be incorrect. Each patient underwent surgery for neural decompression and spinal stabilization, and, in each case, management was altered as a result of the intraoperative histopathologic findings. The three patients were referred to the senior author (R.F.McL.) …
Dynamic average-value modeling of a four-level drive system

Multilevel power converters have gained much attention in recent years due to their high power quality, low switching losses, and high-voltage capability. These advantages make the multilevel converter a candidate for the next generation of naval ship prolusion systems. Evaluation of these systems is typically assisted with a dynamic average-value models in order to rapidly predict system performance under several operating scenarios. In this paper, an average-value model is developed for the four-level diode-clamped converter which takes into account the active capacitor voltage balancing control. This model performance prediction is compared to a detailed model and laboratory measurements on an 18 kW rectifier/inverter test system.
Differences in Habitat Use by Blanding's Turtles, Emydoidea blandingii, and Painted Turtles, Chysemys picta, in the Nebraska Sandhills

We sampled a variety of wetlands in the Nebraska sandhills at Valentine National Wildlife Refuge. Significantly more individuals of painted turtles (Chrysemys picta) occurred in lakes and open waters than in marshes or small ponds, and the opposite was true for Blanding's turtles (Emydoidea blandingii). Besides this marked difference in habitat use, 46% of the captured E. blandingii in pond/marsh habitat were juveniles, but only 31.6% in lakes and open water. Current information suggests that marshes and small ponds are important habitat for juvenile turtles, especially Emydoidea blandingii.