cssi/SciSciGPT-SciSciNet huggingface dataset:
Impurity-induced frustration: low-energy model of diluted oxides

We provide a detailed derivation of the low-energy model for Zn-diluted La${}_{2}$CuO${}_{4}$ in the limit of low doping together with a study of the ground-state properties of that model. We consider Zn-doped La${}_{2}$CuO${}_{4}$ within a framework of the three-band Hubbard model, which closely describes high-${T}_{c}$ cuprates on the energy scale of the most relevant atomic orbitals. To obtain the low-energy effective model, we first determine hybridized electronic states of CuO${}_{4}$ and ZnO${}_{4}$ plaquettes within the CuO${}_{2}$ planes. Qualitatively, we find that the hybridization of zinc and oxygen orbitals can result in an impurity state with the energy $\ensuremath{\varepsilon}$, which is lower than the effective Hubbard gap $U$. In the limit of the effective hopping integral $t\ensuremath{\ll}\ensuremath{\varepsilon}$, $U$, the low-energy, spin-only Hamiltonian includes terms of the order ${t}^{2}/U$ and ${t}^{4}/{\ensuremath{\varepsilon}}^{3}$. That is, besides the usual nearest-neighbor superexchange $J$ terms of order ${t}^{2}/U$, the low-energy model contains impurity-mediated, further-neighbor frustrating interactions among the Cu spins surrounding Zn sites in an otherwise unfrustrated antiferromagnetic background. These terms, denoted as ${J}_{\mathrm{Zn}}^{\ensuremath{'}}$ and ${J}_{\mathrm{Zn}}^{\ensuremath{'}\ensuremath{'}}$, are of order ${t}^{4}/{\ensuremath{\varepsilon}}^{3}$ and can be substantial when $\ensuremath{\varepsilon}\ensuremath{\sim}U/2$, the latter value corresponding to the realistic CuO${}_{2}$ parameters. In order to verify this spin-only model, we subsequently apply the $T$-matrix approach to study the effect of impurities on the antiferromagnetic order parameter. Previous theoretical studies, which include only the dilution effect of impurities, show a large discrepancy with experimental data in the doping dependence of the staggered magnetization at low doping. We demonstrate that this discrepancy is eliminated by including impurity-induced frustrations into the effective spin model with realistic CuO${}_{2}$ parameters. Recent experimental study shows a significantly stronger suppression of spin stiffness in the case of Zn-doped La${}_{2}$CuO${}_{4}$ compared to the Mg-doped case and thus gives strong support to our theory. We argue that the proposed impurity-induced frustrations should be important in other strongly correlated oxides and charge-transfer insulators.
Nonlinear Viscoelastic Behavior of Active Fiber Composites

In the present study, viscoelastic response of an active fiber composite (AFC) is investigated by conducting stress relaxation and creep deformation tests, and the quasi-linear viscoelastic (QLV) constitutive model is used to describe the viscoelastic response of the AFC. The AFC understudy consists of unidirectional long piezoelectric ceramic fibers embedded in an epoxy polymer, encapsulated between two Kapton layers with interdigitated surface electrodes. The relaxation and creep experiments are performed by loading the AFC samples along the longitudinal axis of the fibers, under several strain and stress levels at three temperatures, namely 25 o C, 50 o C and 75 o C. The experimental results reveal the nonlinear viscoelastic behavior of the composite. Next, simulation and prediction of the viscoelastic response, including stress relaxation and creep deformation of the material, are done by using semi-analytical QLV model in which a relaxation time-dependent function is used, which also depends on strain and temperature. The results from the model are compared with those from the experiments. In general, the experimental and simulation results are in good agreement, except in the case of some of the creep responses, where considerable discrepancies are seen between the experimental and analytical approaches; possible reasons for these differences are discussed in details.
Regulation of Amphiphysin1 by Mitogen-activated Protein Kinase ITS SIGNIFICANCE IN NERVE GROWTH FACTOR RECEPTOR-MEDIATED ENDOCYTOSIS

Amphiphysin1, which can simultaneously bind to dynamin1 and the clathrin adaptor AP-2, is essential for dynamin1 recruitment during receptor-mediated endocytosis, but little is known about its regulatory mechanism. Here, we purified a 120-kDa mitogen-activated protein kinase (MAPK) substrate protein from porcine brains and identified the protein as amphiphysin1. Serine phosphorylation of amphiphysin1 was rapidly induced by nerve growth factor (NGF) in PC12 cells, and the induction was blocked by a MAPK inhibitor. Furthermore, when phosphorylated by MAPK in vitro or by NGF treatment in vivo, amphiphysin1 failed to bind to AP-2, but its association with dynamin1 was unaffected. Consistent with this, mutation of consensus MAPK phosphorylation sites increased amphiphysin1 binding to AP-2 and their intracellular colocalization. Thus, we propose that MAPK phosphorylation of amphiphysin1 controls NGF receptor/TrkA-mediated endocytosis by terminating the amphiphysin1-AP-2 interaction. This perhaps helps to regulate the availability of amphiphysin1-dynamin1 complexes for binding to the endocytic vesicle.
Molecular transport of proteins through nanoporous membranes fabricated by interferometric lithography

Millimeter sized arrays of uniformly-distributed nanopores (180–220 nm) were created in thin (200 nm) silicon nitride membranes using interferometric lithography. Molecular transport properties of the fabricated devices were investigated experimentally and compared with those of state-of-the-art polycarbonate track etched membranes. Two similarly-sized proteins, bovine serum albumin (BSA) and bovine hemoglobin (BHb), were used as permeates in the transport experiments. Up to 40 fold higher pore fluxes were achieved with unmodified silicon nitride membranes relative to thicker commercial nanoporous membranes. Similarly, in mixed protein experiments, ∼5.0 and 1.9 fold higher BSA and BHb selectivities were obtained with fabricated thin membranes at pH 4.7 and 7.0, respectively, relative to the commercial nanoporous membranes.
Academic Discussions An Analysis of Instructional Discourse and an Argument for an Integrative Assessment Framework

This article describes the structure of academic discussions during the implementation of a literacy curriculum in the upper elementary grades. The authors examine the quality of academic discussion, using existing discourse analysis frameworks designed to evaluate varying attributes of classroom discourse. To integrate the overlapping qualities of these models with researchers’ descriptions of effective discussion into a single instrument, the authors propose a matrix that (1) moves from a present/absent analytic tendency to a continuum-based model and (2) captures both social and cognitive facets of quality academic discourse. The authors conclude with a discussion of how this matrix could serve to align teachers’ and researchers’ identification of quality academic discussion and the process by which users could measure improvement in students’ discourse skills over time.
How Different Are Students of School Psychology and Clinical Psychology

Based on many years of training students in both school and clinical psychology, the authors have formulated some impressions of differences and similarities found in these trainees. While generalizations remain tentative and call for research, the students in each of these disciplines seem to present different patterns in cognitive styles, perceptions of clients, conceptions of professional role, and personality characteristics. In personality, the students in these fields often display differences in need for structure, need for external support, social maturity, and desire for autonomous professional functioning. Differences seem to be related to variations in previous work and educational experiences, and to differences in age, sex and marital status. Implications for quality of service offered and training needs are outlined.
Effect of hypophysectomy and growth hormone on the inductions of rat liver tyrosine aminotransferase and tryptophan oxygenase by hydrocortisone.

Abstract Hypophysectomy causes major increases in the inductions of rat liver tyrosine aminotransferase and tryptophan oxygenase by hydrocortisone: the maximal levels reached are several-fold higher, and the time during which the levels remain elevated is several hours longer than in adrenalectomized (or intact) rats. A single injection of growth hormone preparation reverses this effect of hypophysectomy. The substrate-induction of tryptophan oxygenase is unaffected by either hypophysectomy or growth hormone. The results suggest that in intact rats the presence of growth hormone (or other pituitary factor) may limit the extent to which the level of appropriate liver enzymes respond to the stress-mediated hypersecretion of glucocorticoids.
Two- versus three-dimensional quantum confinement in indium phosphide wires and dots

The size dependence of the bandgap is the most identifiable aspect of quantum confinement in semiconductors; the bandgap increases as the nanostructure size decreases. The bandgaps in one-dimensional (1D)-confined wells, 2D-confined wires, and 3D-confined dots should evolve differently with size as a result of the differing dimensionality of confinement. However, no systematic experimental comparisons of analogous 1D, 2D or 3D confinement systems have been made. Here we report growth of indium phosphide (InP) quantum wires having diameters in the strong-confinement regime, and a comparison of their bandgaps with those previously reported for InP quantum dots. We provide theoretical evidence to establish that the quantum confinement observed in the InP wires is weakened to the expected extent, relative to that in InP dots, by the loss of one confinement dimension. Quantum wires sometimes behave as strings of quantum dots, and we propose an analysis to generally distinguish quantum-wire from quantum-dot behaviour.
COSUPPRESSION IN DROSOPHILA: GENE SILENCING OF ALCOHOL DEHYDROGENASE BY WHITE-ADH TRANSGENES IS POLYCOMB DEPENDENT

Abstract When two to six copies of a white promoter- Alcohol dehydrogenase ( Adh ) reporter fusion gene are introduced into the genome, the expression is progressively reduced both in larvae and adults rather than the expected gene dosage effect. In addition, multiple transgenes reduce endogenous Adh transcripts, a result that is strongly analogous to "cosuppression" phenomena described in many plant species but which has not been previously observed in animals. Silencing of the Adh gene is not influenced by zeste -dependent transvection but strongly affected by the Polycomb and Polycomblike mutations. Polycomb and polyhomeotic proteins are bound to the chromatin at the sites of the repressed w-Adh transgenes.
Location Is Everything: An Educational Primer for Use with “Genetic Analysis of the Ribosome Biogenesis Factor Ltv1 of Saccharomyces cerevisiae”

The article by Merwin et al. in the November 2014 issue of GENETICS provides insight into ribosome biogenesis, an essential multistep process that involves myriad factors and three cellular compartments. The specific protein of interest in this study is l ow- t emperature v iability protein (Ltv1), which functions as a small ribosomal subunit maturation factor. The authors investigated its possible additional function in small-subunit nuclear export. This Primer provides information for students to help them analyze the paper by Merwin et al. (2014), including an overview of the authors’ research question and methods. Related article in GENETICS : Merwin, J. R., L. B. Bogar, S. B. Poggi, R. M. Fitch, A. W. Johnson, and D. E. Lycan, 2014 Genetic analysis of the ribosome biogenesis factor Ltv1 of Saccharomyces cerevisiae . Genetics 198: 1071–1085
Synthesis of 4-(4-iodophenyl)piperazine and the 1-carboxamidino derivative

The previously unreported 4-(4-iodophenyl)piperazine (2) was synthesized in a 70% yield and characterized. The reaction of 2 with S-methylthiouronium sulfate gave the corresponding carboxamidino derivative 4 in a 61% yield. The tlc properties of 4 were identical with those of the radioiodinated material that had been prepared and evaluated as a potential myocardial imaging radiopharmaceutical.
Using information to generate derivative coordinates from noisy time series

Abstract This paper describes an approach for recovering a signal, along with the derivatives of the signal, from a noisy time series. To mimic an experimental setting, noise was superimposed onto a deterministic time series. Data smoothing was then used to successfully recover the derivative coordinates; however, the appropriate level of data smoothing must be determined. To investigate the level of smoothing, an information theoretic is applied to show a loss of information occurs for increased levels of noise; conversely, we have shown data smoothing can recover information by removing noise. An approximate criterion is then developed to balance the notion of information recovery through data smoothing with the observation that nearly negligible information changes occur for a sufficiently smoothed time series.
Use of dispersants to enhance incorporation rate of nano-particles into electrodeposited films

Abstract The effect of a cationic dispersant, polyethyleneimine (PEI) on the co-deposition of 45–55 nm and 1.0 μm SiC particles with Ni on a rotating disk electrode is investigated. Addition of 500 ppm of PEI into a Watts bath increases the SiC fraction in the nano-composites without affecting the electrodeposition kinetics, however films have undesired properties, as evidenced by cracks. A pre-coating procedure, in which nano-particles are treated with 500 ppm PEI prior to introduction into the plating bath is described. The pre-coating method increases the SiC incorporation to values as high as 23 vol%, one of the highest reported values for nano-particles in electrodeposited films, without decreasing the current efficiency. In addition, the pre-coating method facilitates bath-composition optimization when, for example, leveling agents are employed; otherwise the leveling agent and PEI competitively adsorb onto the SiC particles. The efficacy of employing the pre-coating procedure in manufacturing, where plating baths need a long life, may be satisfactory. Strategies where dispersants are first attached to ceramic particles prior to integration into a plating bath containing other additives may lead to high volume fractions of particles thus harder deposits. The detailed procedures to achieve high-volume fractions required modification when transitioning from micron- to nano-sized particles.
Adenosine receptor blockade enhances glycolysis in hypoperfused guinea-pig myocardium

Objective: This study tested the hypothesis that endogenous adenosine depresses anaerobic glycolysis in preischaemic and moderately ischaemic myocardium. Methods: Isolated, working guinea-pig hearts, perfused with glucose-fortified Krebs-Henseleit buffer, were subjected to 15 min mild hypoperfusion (coronary flow 60% of baseline) followed by 10 min ischaemia (coronary flow 20% of baseline). Adenosine A1 receptors were blocked with 8- p -sulfophenyl theophylline (8-SPT; 20 μM). Glucose oxidation and lactate production from exogenous glucose were assessed from 14CO2 and [14C]lactate formation, respectively, from [U-14C]glucose. Energy metabolites, glycolytic intermediates and glycogen were measured in extracts of stop-frozen preischaemic, mildly hypoperfused and ischaemic myocardium. Results: Adenosine receptor blockade did not affect left ventricular function assessed from heart rate × pressure product and pressure × volume work although coronary flow was slightly reduced. Adenosine receptor blockade increased glucose uptake ( P < 0.05) by 100% during preischaemia and by 74% during mild hypoperfusion, and increased lactate production from exogenous glucose ( P < 0.05) by 89% during preischaemia and fourfold during mild hypoperfusion, but did not stimulate glucose oxidation under any condition. Glycogen degradation was not increased by adenosine receptor blockade during ischaemia. Crossover plots of glycolytic intermediates revealed that phosphofructokinase was activated by adenosine receptor blockade at all three levels of perfusion. Conclusion: Endogenous adenosine attenuates anaerobic glycolysis in normally perfused, hypoperfused and ischaemic myocardium by blunting phosphofructokinase activity; this effect is mediated by adenosine A1 receptors.
The (dys)functional extracellular matrix

The extracellular matrix (ECM) is a major component of the biomechanical environment with which cells interact, and it plays important roles in both normal development and disease progression. Mechanical and biochemical factors alter the biomechanical properties of tissues by driving cellular remodeling of the ECM. This review provides an overview of the structural, compositional, and mechanical properties of the ECM that instruct cell behaviors. Case studies are reviewed that highlight mechanotransduction in the context of two distinct tissues: tendons and the heart. Although these two tissues demonstrate differences in relative cell–ECM composition and mechanical environment, they share similar mechanisms underlying ECM dysfunction and cell mechanotransduction. Together, these topics provide a framework for a fundamental understanding of the ECM and how it may vary across normal and diseased tissues in response to mechanical and biochemical cues. This article is part of a Special Issue entitled: Mechanobiology.
Sino-Tibetan Negation and the Case of Galo: Explaining a Distributional Oddity in Diachronic Terms

While the vast majority of Sino-Tibetan (=Trans-Himalayan) languages have a pre-head predicate negator, Tani is one of a small handful of subgroups whose languages display an exclusively post-head negator. This negator, furthermore, is somewhat unusual in having both derivation-like and inflection-like properties, and in occupying an 'intermediate' position between derivations and inflections in the predicate stem. This article proposes a common explanation for both facts, by hypothesizing that reanalysis of an AUX-final serial verb construction as a single predicate word has resulted in realignment of an earlier pre-head auxiliary negator as a predicate suffix with leftward scope over the predicate stem. This is similar to another channel found in some Tibeto-Burman languages in which a prefixal negator fuses with a clause-final auxiliary to become a suffix (as in Kuki-Chin and 'Naga'); however, I argue it to be ultimately somewhat different. These arguments are made on the basis of a more comprehensive description of negation in Galo (Tibeto-Burman ＞ Tani, Eastern Himalaya) than was provided in Post (2007); as such, a second goal of the paper is to contribute to the typology of negation in Asian languages more generally.
Space-time modeling for the Missouri Turkey Hunting Survey

The Missouri Turkey Hunting Survey (MTHS) is a postseason mail survey conducted by the Missouri Department of Conservation. The 1996 MTHS provides information concerning the number of turkeys harvested by hunters on each day and the total number of trips made to the counties by these hunters on each day of the hunting season. The success rates are then found from this information. Small sample sizes produce large standard errors for the estimates at the county level. We use a Bayesian hierarchical generalized linear model to estimate daily hunting success rates at the county level. The model includes an autoregressive process for the days of the hunting season and spatially correlated random geographic effects. The computations are performed using Gibbs sampling and adaptive rejection sampling techniques. Results show that there are significant spatial corelations between counties and correlations between days of the hunting season. The estimates are close to the frequency estimates at the state level and much more stable at the county level.
Policing the “Penn State Crisis”: Violence, Power, and the Neoliberal University

Within this article, the authors critically introduce and interrogate the ongoing crisis/scandal at Penn State University within the intersecting vectors of institutional violence, the commodification of higher education, media coverage of the event and its aftermath, spaces of resistance, and the complicated legacy of Joe Paterno. Additionally, and on a broader scale, they argue that within the privileged spaces of academia, scholars have a responsibility to their communities to push for greater transparency and accountability within their institutions, join and support faculty unions, and resist the further neoliberalization of higher education.
Design of Ultrathin Composite Self-Deployable Booms

Recently developed analysis techniques for thin shells that can be folded elastically and are able to self-deploy are used to develop an iterative design approach for this type of structure. The proposed approach considers a series of potential designs and then evaluates, for each trial design, key performance parameters through a complete simulation of its folding and deployment behavior. This design approach is applied to a boom concept consisting of a thin-walled tube in which two tape-spring hinges are made by cutting diametrically opposite slots; the geometry of the slots is fully defined by the length, width, and end diameter of the cuts. A design for a two-hinge, 1-m-long, lightweight self-deployable boom that can be wrapped around a small spacecraft is developed; the hinge geometry is chosen such that there is no damage during folding/deployment of the boom, and also the boom becomes latched at the first attempt. The chosen boom design is successfully validated experimentally.
Comparison of TaqMan and SYBR Green qPCR Methods for Quantitative Gene Expression in Tung Tree Tissues

Quantitative real-time-PCR (qPCR) is widely used for gene expression analysis due to its large dynamic range, tremendous sensitivity, high sequence specificity, little to no postamplification processing, and sample throughput. TaqMan and SYBR Green qPCR are two frequently used methods. However, direct comparison of both methods using the same primers and biological samples is still limited. We compared both assays using seven RNAs from the seeds, leaves, and flowers of tung tree (Vernicia fordii), which produces high-value industrial oil. High-quality RNA were isolated from tung tissues, as indicated by a high rRNA ratio and RNA integrity number. qPCR primers and TaqMan probes were optimized. Under optimized conditions, both qPCR gave high correlation coefficiency and similar amplification efficiency, but TaqMan qPCR generated higher y-intercepts than SYBR Green qPCR, which overestimated the expression levels regardless of the genes and tissues tested. This is validated using well-known Dgat2 and Fadx gene expression in tung tissues. The results demonstrate that both assays are reliable for determining gene expression in tung tissues and that the TaqMan assay is more sensitive but generates lower calculated expression levels than the SYBR Green assay. This study suggests that any discussion of gene expression levels needs to be linked to which qPCR method is used in the analysis.
Critical thinking in accounting education: processes, skills and applications

Explains that many prestigious bodies, including the American Assembly of Collegiate Schools of Business and the Accounting Change Commission, have asked accounting educators to improve their students’ critical thinking skills. Suggests that the literature contains few examples of how to apply such skills in an accounting environment and how to teach such skills as efficiently as possible. Explains and provides examples of such critical thinking skills. Shows how to incorporate such skills in the classroom.
Stereoselective actions of halothane at GABAA receptors

Isoflurane anesthesia exhibits stereoselectivity, and a corresponding stereoselectivity ((+)->(−)-isomer) has been reported at GABAA receptors in vitro. The objective of the present study was to determine if the positive modulatory actions of halothane at GABAA receptors exhibited a similar stereoselectivity. Both (R)- and (S)-halothane ((+)- and (−)- isomers, respectively) enhanced []flunitrazepam binding to brain membranes in a concentration dependent manner without a significant difference in either potency (EC50) or efficacy (Emax). While both (R)- and (S)-halothane enhanced []muscimol binding, the potency of the (+)-isomer was slightly greater than the corresponding (−)-isomer (0.91±0.17 versus 1.45±0.04% atmospheres, respectively (P<0.02)). Thus, subtle structural differences between inhalational anesthetics can have a significant impact on the degree of stereoselectivity at the receptor level and may provide insights for the development of more specific drugs.
“What Do You Want to Be … When You Grow Up?” Recollections of a Slavic Librarian Part I: The Cold War, Dartmouth, and University of Illinois Years, 1945–1987

In this article, the author describes his experience growing up in Washington, DC, during the Cold War, as an undergraduate at Dartmouth College, as a graduate student at the University of Illinois at Urbana–Champaign, and as a librarian in the Slavic and East European Library, University of Illinois at Urbana–Champaign.
Statistical Modeling of the Interference Noise Generated by Computing Platforms

The trend of electronic systems toward higher integration and higher performance has also brought new challenges to the design of radio transceivers. The decrease of switching times accompanied by the increase of clock speeds, data rates, and interconnection speeds contribute to improve the overall system performance. At the same time, they also affect wireless communications due to an increment of the emissions of electromagnetic radiation. In this paper, we show that the statistics of the baseband components of the noise follow the K-distribution. The one-sided version of this distribution has been derived before as a model for the envelope of sea echo in radar and sonar, however, we show here that its two-sided version can also be used to model the interference noise that affects a transceiver located inside a computer platform. The model shows good agreement with experimental measurements. Also, a closed-form expression of the bit error rate (BER) and some bounds are computed.
Lack of native species recovery following severe exotic disturbance in southern Californian shrublands

Summary 1. Urban and agricultural activities are not part of natural disturbance regimes and may bear little resemblance to them. Such disturbances are common in densely populated semi-arid shrub communities of the south-western US, yet successional studies in these regions have been limited primarily to natural successional change and the impact of human-induced changes on natural disturbance regimes. Although these communities are resilient to recurrent and large-scale disturbance by fire, they are not necessarily well-adapted to recover from exotic disturbances. 2. This study investigated the effects of severe exotic disturbance (construction, heavy-vehicle activity, landfill operations, soil excavation and tillage) on shrub communities in southern California. These disturbances led to the conversion of indigenous shrublands to exotic annual communities with low native species richness. 3. Nearly 60% of the cover on disturbed sites consisted of exotic annual species, while undisturbed sites were primarily covered by native shrub species (68%). Annual species dominant on disturbed sites included Erodium botrys, Hypochaeris glabra, Bromus spp., Vulpia myuros and Avena spp. 4. The cover of native species remained low on disturbed sites even 71 years after initial exotic disturbance ceased. Native shrub seedlings were also very infrequent on disturbed sites, despite the presence of nearby seed sources. Only two native shrubs, Eriogonum fasciculatum and Baccharis sarothroides, colonized some disturbed sites in large numbers. 5. Although some disturbed sites had lower total soil nitrogen and percentage organic matter and higher pH than undisturbed sites, soil variables measured in this study were not sufficient to explain variations in species abundances on these sites. 6. Non-native annual communities observed in this study did not recover to a predisturbed state within typical successional time (< 25 years), supporting the hypothesis that altered stable states can occur if a community is pushed beyond its threshold of resilience.
Binding Affinity and Specificity of the Estrogen Receptor of the Rat Uterus and Anterior Pituitary

The soluble supernatant fractions of the uterus and anterior pituitary from ovariectomized adult rats contain 3H-17β-estradiolbinding proteins with identical sedimentation coefficients (8.6±0.2S). Using the Clark and Gorski estrogen receptor assay, the uterine estrogen receptor has a dissociation constant of 1.55×1O−9 (±0.07)M for 3H-17β-estradiol, which is essentially identical with the value of 1.40×10−9 (±0.11)M for the estrogen receptor of the anterior pituitary. The 17β-estradiol binding capacities of the uterus and anterior pituitary estrogen receptors are 0.56 and 0.24 pmole/mg of cell protein, respectively. However, on a per cell basis, the number of receptors in the uterine (∼16,000) or anterior pituitary cell (∼12,000) is of a similar order of magnitude. Estrogenic substances or estrogenic antagonists compete with 3H-17β-estradiol for binding to the receptors of both the anterior pituitary and uterus in the same sequence and to the same degree; that is, diethylstil bestrol≥ethynylestradiol>estro...
Geometry of Fluvial and Deltaic Sandstones (Pennsylvanian and Permian), North-Central Texas: ABSTRACT

Upper Pennsylvanian and Lower Permian rocks of the eastern shelf in north-central Texas are composed of 10-15 repetitive sequences including open shelf, deltaic, fluvial, and interdeltaic depositional systems. Sediments derived from the Ouachita Mountains and associated piedmont were transported westward across a narrow coastal plain. Fluvial and deltaic sandstone facies define a southwest paleoslope of about 5 mi. Sandstones are delta-front, distributary-mouth-bar, distributary- and fluvial-channel, and destructional-bar facies. Distributary patterns represent distal deposition in the upslope area. Belt sandstones, typified by unusually thick fluvial channels, prograded far downslope. Composite patterns include distributary and belt sandstones representing complex progradational history. Rocks display ½° northwest regional dip; negative structure residuals outline a broad area within which 70% of the deltaic facies were deposited. Elongate sandstones generally are arranged parallel with paleoslope in vertically offset patterns controlled by differential compaction of fluvial and deltaic sands and interdistributary muds. Multistory sandstone bodies were deposited along narrow, structurally unstable belts which were periodically overloaded and later reoccupied by prograding deltas. Initial Cisco deltas followed a paleosurface grain controlled by underlying bank limestones; this paleoslope orientation was maintained during deposition of 1,200 ft of Cisco strata. Each fluvial-deltaic system inherited its geometry from previous systems and, in turn, provided control for the next deltaic episode. Stratigraphic and structural mapping utilizing mud decompaction techniques confirm the roles played by compaction and stru ture in controlling the geometry of sandstone bodies. End_of_Article - Last_Page 2033------------
Characterization of stable high molecular weight mutagenic product(s) of plant-activated m-phenylenediamine

Abstract Monocyclic aromatic amines are environmental contaminants and many are promutagens and procarcinogens. Cultured tobacco cells, strain TX1, activated m-phenylenediamine into a frameshift mutagen that reverted the hisD3052 allele in Salmonella typhimurium strains TA98 and YG1024. However, the plant-activated products were refractory in strain TA98/1,8-DNP6. This indicated that these plant-activated products were substrates for bacterial acetyl-CoA: N-hydroxyarylamine O-acetyltransferase. A stable, high molecular weight ( > 300 kDa) proximal mutagen was isolated by molecular ultrafiltration membranes. No parent compound was associated with the isolated mutagenic fraction. The high molecular weight fraction induced mutation in S. typhimurium strains TA98, YG1021 and YG1024. From these data we propose a model for the plant-activation of aromatic amine promutagens.
Group culture and its effect on innovative productivity

Abstract In this study, the concept of internal receptivity to new ideas and innovation, termed innovativeness, was explored as an aspect of group culture. The connection between innovative productivity and culture was tested empirically at the group level of analysis. Innovativeness was hypothesized to effect innovative productivity (e.g., the number of new technical innovations adopted), and it was hypothesized to be related to beliefs about four other dimensions of group culture: decision making, power sharing, support and collaboration, and an emphasis on developing people and careers. This study included 8,969 individuals located in 38 groups in a large research and development agency of the United States Government. Results confirmed the hypothesized relationship between innovativeness of the culture and innovative productivity. After controlling for structural properties (i.e., size of group and work force composition), higher levels of innovativeness were significantly associated with greater innovative productivity; further, groups with cultures that emphasized people and career development and participative decision making were associated with higher levels of cultural innovativeness.
Cane Molasses for Poultry

Abstract Cane molasses, or blackstrap, the byproduct of the manufacture of cane sugar, is palatable and much relished by farm animals. Henry and Morrison1 report that, when fed in moderate amounts, it is about equal, pound for pound, to corn for fattening farm animals. A survey of the literature reveals practically no data on the feeding value of molasses for poultry. Graham2, Lee3, and Lippincott4 have mentioned its use in fattening rations. Owing to the cheapness and abundance of the product, it could well be included in poultry rations if found to be of benefit. The object of the experiments reported here was to determine the value of cane molasses as a substitute for part of the cereal grains in poultry rations. EXPERIMENTS WITH LAYING HENS In Trial 1 there were 60 two- and three-year-old Leghorn hens in each pen. The experiment ran from October 21, 1926, to March 4, 1927. . . .
Vibrotactile amplitude discrimination capacity parallels magnitude changes in somatosensory cortex and follows Weber’s Law

In this study, we investigated the changes in perceptual metrics of amplitude discrimination that were observed in ten healthy human subjects with increasing intensities of stimulation. The ability to perceive differences in vibrotactile amplitude changed systematically with increasing stimulus magnitude (i.e., followed Weber's Law) in a near linear fashion (R (2) = 0.9977), and the linear fit determined by the amplitude discrimination task predicted the subjects' detection thresholds. Additionally, the perceptual metrics correlated well with observations from a previously reported study in which measures of SI cortical activity in non-human primates (squirrel monkeys) evoked by different amplitudes of vibrotactile stimulation were obtained (Simons et al. in BMC Neurosci 6:43, 2005). Stimuli were delivered simultaneously to two different skin sites (D2 and D3), enabling a method for the relatively rapid acquisition of the data. Stability and robustness of the measure, its rapid acquisition, and its apparent relationship with responses previously observed in SI cortex, led to the conclusion that deviations from the baseline values observed in the obtained perceptual metric could provide a useful indicator of cerebral cortical health.
Conjugated Polymers as Photoredox Catalysts: Visible-Light-Driven Reduction of Aryl Aldehydes by Poly(p-phenylene)

The use of visible light in photocatalysis has been intensively studied because of its natural abundance, ease of use, and promising potential for industrial applications. However, there are several challenges to utilizing visible light for organic functional group transformations. These challenges include the low absorptivity of most organic compounds in the visible spectrum, and side reactions are often prevalent in photochemical reactions. Visible-light-sensitive catalysts offer a means to overcome these obstacles. Conjugated polymers are semiconductors that offer a large range of redox potentials, they are stable, and they often absorb visible light. Despite these desirable properties for photocatalysis, only a limited number of organic reactions utilizing conjugated polymers as photocatalysts have been reported. In one such example, poly(p-phenylene) was used to induce the pinacol coupling reaction of benzaldehyde upon irradiation with visible light. In this work, visible light, thiols, and poly(p-phenylene) were employed to reduce aryl aldehydes to their respective alcohols to better characterize the reaction mechanisms of this system. The effects of varying reaction conditions on the rate of photocatalysis indicated interfacial electron transfer from the poly(p-phenylene) surface to the substrate as the initial productive step. Additionally, the chemoselective reduction of aryl aldehydes over aryl ketones and alkyl aldehydes was achieved with this system.
Synthesis with good enantiomeric excess of both enantiomers of α-ketols and acetolactates by two thiamin diphosphate-dependent decarboxylases

In addition to the decarboxylation of 2-oxo acids, thiamin diphosphate (ThDP)-dependent decarboxylases/dehydrogenases can also carry out so-called carboligation reactions, where the central ThDP-bound enamine intermediate reacts with electrophilic substrates. For example, the enzyme yeast pyruvate decarboxylase (YPDC, from Saccharomyces cerevisiae) or the E1 subunit of the Escherichia coli pyruvate dehydrogenase complex (PDHc-E1) can produce acetoin and acetolactate, resulting from the reaction of the central thiamin diphosphate-bound enamine with acetaldehyde and pyruvate, respectively. Earlier, we had shown that some active center variants indeed prefer such a carboligase pathway to the usual one [Sergienko, Jordan, Biochemistry 40 (2001) 7369-7381; Nemeria et al., J. Biol. Chem. 280 (2005) 21,473-21,482]. Herein is reported detailed analysis of the stereoselectivity for forming the carboligase products acetoin, acetolactate, and phenylacetylcarbinol by the E477Q and D28A YPDC, and the E636A and E636Q PDHc-E1 active-center variants. Both pyruvate and beta-hydroxypyruvate were used as substrates and the enantiomeric excess was analyzed by a combination of NMR, circular dichroism and chiral-column gas chromatographic methods. Remarkably, the two enzymes produced a high enantiomeric excess of the opposite enantiomer of both acetoin-derived and acetolactate-derived products, strongly suggesting that the facial selectivity for the electrophile in the carboligation is different in the two enzymes. The different stereoselectivities exhibited by the two enzymes could be utilized in the chiral synthesis of important intermediates.
Waiting and the Period of Production

"They also serve who only stand and wait." — Milton Statement of the problems, 351. — Bohm-Bawerk's analysis, 352. — Interest in a two-sector economy, 355. — Digression on waiting, 359. — Calculation of the period of production, 362. — Necessity of positive rate of interest, 364. — Sketch of more complicated models, 365. — Conclusions, 367. — Mathematical appendix, 367; the bathtub theorem, 367; solution of the Solow two-sector model, 368; direct calculation of the period of investment of waiting, 370.
Interplay of antibiotics and bacterial inoculum on suture-associated biofilms.

Background—Biofilms are often antibiotic resistant, and it is unclear if prophylactic antibiotics can effectively prevent biofilm formation. Experiments were designed to test the ability of high (bactericidal) concentrations of ampicillin (AMP), vancomycin (VAN), and oxacillin (OXA) to prevent formation of suture-associated biofilms initiated with low (10 4 ) and high (10 7 ) numbers of Staphylococcus aureus. Materials and methods—S. aureus biofilms were cultivated overnight on silk suture incubated in biofilm growth medium supplemented with bactericidal concentrations of AMP, VAN, or OXA. Standard microbiological methods were used to quantify total numbers of viable suture-associated S. aureus. Crystal violet staining followed by spectroscopy was used to quantify biofilm biomass, which includes bacterial cells plus matrix components. To observe the effects of antibiotics on the microscopic appearance of biofilm formation, biofilms were cultivated on glass slides, then stained with fluorescent dyes, and observed by confocal microscopy. Results—In the presence of a relatively low inoculum (10 4 ) of S. aureus cells, bactericidal concentrations of AMP, VAN, or OXA were effective in preventing development of sutureassociated biofilms. However, similar concentrations of these antibiotics were typically ineffective in preventing biofilm development on sutures inoculated with 10 7 S. aureus, a concentration relevant to contaminated skin. Confocal microscopy confirmed that bactericidal concentrations of AMP, VAN, or OXA inhibited, but did not prevent, development of S. aureus biofilms. Conclusion—Bactericidal concentrations of AMP, VAN, or OXA inhibited formation of sutureassociated biofilms initiated with low numbers (10 4 ), but not high numbers (10 7 ), of S. aureus cells.
Stability of the vicarious cold calibration statistic for the GPM constellation

The vicarious cold calibration statistic has been analyzed to determine its stability. Modeled top of atmosphere brightness temperatures representing microwave radiometer observations are computed for the month of July 2005 using a radiative transfer model. The vicarious cold calibration algorithm is applied to the population of brightness temperatures along with two other statistics for comparison. The stability is assessed by perturbing the sea surface temperatures and atmospheric water vapor in the model to simulate a global warming event. The results show that the vicarious cold calibration statistic is the most stable since it has the least variation for the simulated warming event.
Modeling Self-Organization With Nonwellfounded Set Theory

In this article, I use graphical tools from nonwellfounded set theory to model a variety of complex systems. I focus in particular on autocatakinetic systems. First there is a tutorial, explaining how to use the graphical tools of nonwellfounded set theory to model complex systems. I use these graphical tools to show that autocatakinetic systems are closed to efficient cause. Then I compare autocatakinetic systems with autopoietic systems. Finally, I use the graphical tools to examine autocatakinetic systems in light of Aristotle's 4 causes.
DNA Damage: Chemistry, Repair, and Mutagenic Potential

Abstract This paper is an overview on the chemical and biochemical effects of three different human carcinogens on DNA in vitro in terms of adducts, their effect on replication, in vitro and in vivo, and their repair by enzymes from human cells. The carcinogenic compounds chosen for specific discussion are N -nitroso alkylating agents: the vinyl chloride metabolite, chloroacetaldehyde (CAA), and the benzene metabolite, p -benzoquinone (p-BQ).
1376 CIRCULATORY EFFECTS OF HYPERINSULINEMIA IN THE NEAR TERM OVINE FETUS

Ovine fetal hyperinsulinemia is associated with increased oxygen consumption, increased glucose uptake and decreased arterial O2 content. We used eight mixed breed ewes with 114-132 day singleton pregnancies to measure the magnitude and distribution of fetal cardiac output in order to define the causes of insulin-induced hypoxemia. During an uninfused control period and again after 12, 24 and 48 hours of exogenous insulin infusion (0.05U/kg/hr), we measured umbilical vein-artery whole blood concentrations of glucose and oxygen. We used the distribution of each of four microsphere injections to determine total cardiac output and organ blood flow. Insulin infusion was associated with increasing insulin concentration following a 12 hour lag period. We confirmed an increase in cardiac output (+19%, P<0.02) and a progressive fall in arterial O2 content (0.33mM to 0.23mM, P<.001). During insulin infusion, blood flow increased to the brain (+50%, P<0.05), adrenal (+56%, P<0.01), and carcass (+44%, P<0.02). Placental blood flow did not change during infusion and fell when expressed as a percentage of cardiac output (45% to 34%, P<.002). The hypoxemia during insulin infusion occurs as a result of increased O2 consumption without a corresponding increase in placental blood flow. If similar effects occur in humans, hyperinsulinemic hypoxia may account for the near term fetal and neonatal mortality among women with poorly controlled diabetes.
A Sensitive and Fast Method for the Determination of Polyamines in Biological Samples. Benzoyl Chloride Pre-Column Derivatization High-Performance Liquid Chromatography

Abstract A sensitive, rapid pre-column derivatization HPLC procedure for determination of biologically important polyamines is described. Benzoylated putrescine, cadaverine, norspermidine, spermidine, norspermine and spermine were separated on reverse-phase column using 42:58 acetonitrile:water as mobile phase and detected by UV absorption at 198 nm. The detection limits were: 0.8 pmol for putrescine, 1 pmol for spermidine and 1.3 pmol for spermine. The method was successfully applied to the analysis of polyamines in small samples of unicellular organisms.
Optimal design for epidemiological studies subject to designed missingness

In large epidemiological studies, budgetary or logistical constraints will typically preclude study investigators from measuring all exposures, covariates and outcomes of interest on all study subjects. We develop a flexible theoretical framework that incorporates a number of familiar designs such as case control and cohort studies, as well as multistage sampling designs. Our framework also allows for designed missingness and includes the option for outcome dependent designs. Our formulation is based on maximum likelihood and generalizes well known results for inference with missing data to the multistage setting. A variety of techniques are applied to streamline the computation of the Hessian matrix for these designs, facilitating the development of an efficient software tool to implement a wide variety of designs.
Quadrature and the development of orientation selective cortical cells by Hebb rules

We describe a new theoretical scenario for the development of orientation selective cells in a self-organizing feedforward network with modifiable synapses. A suitable choice of Hebb rule leads to a system that develops symmetric and antisymmetric response fields (quadrature pairs) at the same time as directional selectivity occurs using inhibition between neighboring cells. Quadrature phase relationships between the response properties of adjacent cortical cells is suggestive of several highly efficient information processing strategies.