cssi/SciSciGPT-SciSciNet huggingface dataset:
Visualization of uncorrelated, tandem symmetry mismatches in the internal genome packaging apparatus of bacteriophage T7

Motor-driven packaging of a dsDNA genome into a preformed protein capsid through a unique portal vertex is essential in the life cycle of a large number of dsDNA viruses. We have used single-particle electron cryomicroscopy to study the multilayer structure of the portal vertex of the bacteriophage T7 procapsid, the recipient of T7 DNA in packaging. A focused asymmetric reconstruction method was developed and applied to selectively resolve neighboring pairs of symmetry-mismatched layers of the portal vertex. However, structural features in all layers of the multilayer portal vertex could not be resolved simultaneously. Our results imply that layers with mismatched symmetries can join together in several different relative orientations, and that orientations at different interfaces assort independently to produce structural isomers, a process that we call combinatorial assembly isomerism. This isomerism explains rotational smearing in previously reported asymmetric reconstructions of the portal vertex of T7 and other bacteriophages. Combinatorial assembly isomerism may represent a new regime of structural biology in which globally varying structures assemble from a common set of components. Our reconstructions collectively validate previously proposed symmetries, compositions, and sequential order of T7 portal vertex layers, resolving in tandem the 5-fold gene product 10 (gp10) shell, 12-fold gp8 portal ring, and an internal core stack consisting of 12-fold gp14 adaptor ring, 8-fold bowl-shaped gp15, and 4-fold gp16 tip. We also found a small tilt of the core stack relative to the icosahedral fivefold axis and propose that this tilt assists DNA spooling without tangling during packaging.
CHANGE IN SULFHYDRYL GROUP MICROENVIRONMENT OF CALF LENS α‐CRYSTALLIN BY 300 nm LIGHT

— The effect of 300 nm irradiation on the sulfhydryl groups of calf lens a-crystallin has been investigated by using specific, covalently bound fluorescent sulfhydryl probes 4–(N-iodoacetoxy)ethyl-N-methylamino-7-n-itrobenz-2-o-xa-1,3-d-iazole (IANBD), N-iodoacetyl-N′-(5-s-ulfo-l-naphthyl) ethylene-diamine (1,5 IAEDANS) and 5-i-odoacetamidofluorescein (IAF). The decrease in tryptophan fluorescence with time of irradiation of a-crystallin, is accompanied by a decrease in the fluorescence of the hydrophobic sulfhydryl label IANBD. In addition, the fluorescence of the surface-sulfhydryl label IAF increased in the irradiated a-crystallin. These results indicate that the sulfhydryl groups are in a more exposed (hydrophilic) environment in the irradiated protein than in the control, possibly because of partial unfolding of the protein. This result is confirmed by fluorescence lifetime measurements with IAEDANS. The decay curve of IAEDANS-α-crystallin has a major lifetime of 15.7 ns and a minor one of 24.6 ns. Upon irradiation, the lifetime of the major component decreases to 10.2 ns and that of the minor component to 21.7 ns. Denatured IAEDANS-α-crystallin has a single lifetime of 10.4 ns. These results show that the photoinduced damage to the tryptophan residues of α-crystallin alters the environment of the sulfhydryl groups and induces a change in the tertiary structure of the protein. Proximity of the cysteine residues to tryptophan in the tertiary structure of the protein may be an important determinant of their susceptibility to photoinduced change.
Optimal Design of Solar Energy Systems With Uncertain Data

The technical and economic characteristics of optimized solar energy systems can be expressed in a concise mathematical expression and this expression manipulated to show the dependence of total system cost on variables such as collector cost and efficiency, weather data, or the cost of the backup fuel. The lack of certain knowledge of future weather, fuel prices, and system performance implies that a system optimized, with respect to an assumed set of these data, may not be optimal with respect to the realities of the operation. This formulation demonstrates clearly how the life cycle costs of the system increase as a result of errors in estimating various system parameters; in most cases, the costs of errors are not large over their expected ranges. In particular, most solar energy systems designed to satisfy a given load (that is, having a given nameplate capacity) should be optimized for the best weather they may encounter, and this design used wherever the systems are economically viable, as it is likely that the savings due to standardization will outweigh the relatively small costs of being imperfectly optimized.
Timelike boundary Liouville theory

The timelike boundary Liouville (TBL) conformal field theory consisting of a negative norm boson with an exponential boundary interaction is considered. TBL and its close cousin, a positive norm boson with a non-hermitian boundary interaction, arise in the description of the $c=1$ accumulation point of $c<1$ minimal models, as the worldsheet description of open string tachyon condensation in string theory and in scaling limits of superconductors with line defects. Bulk correlators are shown to be exactly soluble. In contrast, due to OPE singularities near the boundary interaction, the computation of boundary correlators is a challenging problem which we address but do not fully solve. Analytic continuation from the known correlators of spatial boundary Liouville to TBL encounters an infinite accumulation of poles and zeros. A particular contour prescription is proposed which cancels the poles against the zeros in the boundary correlator $d(\o) $ of two operators of weight $\o^2$ and yields a finite result. A general relation is proposed between two-point CFT correlators and stringy Bogolubov coefficients, according to which the magnitude of $d(\o)$ determines the rate of open string pair creation during tachyon condensation. The rate so obtained agrees at large $\o$ with a minisuperspace analysis of previous work. It is suggested that the mathematical ambiguity arising in the prescription for analytic continuation of the correlators corresponds to the physical ambiguity in the choice of open string modes and vacua in a time dependent background.
Conversion from Geocentric to Geodetic Coordinates

The geodetic latitude and the height of a satellite are obtained as power series in the ellipsoid's eccentricity, the terms being Fourier sums in the geocentric latitude with polynomials in 1/r as coefficients, with a view of determining the height to the fullest accuracy required by altimetry and geodesy from satellites.
Kooperation, Frauen und die F-Quote

Heute wird immer harter um eine Quote von Frauen in Schlusselpositionen gerungen. Warum sind da so wenige Frauen? Sind etwa die bosen Manner dagegen? Ich versuche eine finale Antwort. Nach psychologischen Tests sind Frauen mehr kooperativ gestimmt und Manner mehr kompetitiv. Diese Unterschiede (die es unzweifelhaft statistisch gibt) bedeuten aber, dass im Durchschnitt Manner und Frauen ganz verschiedene, ja gegensatzliche Wirtschaftsauffassungen haben. Wer „Mehr Frauen!“ will, sollte sich dann auch „Mehr Kooperation!“ auf die Fahnen schreiben etc. DAS ist das Problem! Die Manner sind gar nicht „gegen die Frauen“, sondern gegen deren kooperativen „weiche“ Auffassungen. Und deshalb werden Frauen nicht so oft befordert – es sei denn, sie haben typisch mannlich kompetitive „harte“ Weltsichten.
Ergodization rates for linear flow on the torus

We estimate the rate at which the image of a point fills the flat Euclidean α-torus when subjected to linear flow satisfying certain nonresonance or near-nonresonance conditions arising naturally in perturbation theory for ODEs. The estimates are explicit and display dependence on all relevant parameters but are not sharp. These results were used to estimate the maximum time until near-collision with nuclei for highly energetic charged particles traveling through crystals in directions “far from channeling directions” and are presented here with complete proofs.
Valence Bond and Spin-Peierls Ground States of Low-Dimensional Quantum Antiferromagnets

The nature of the ground state in the non-Neel phase of Heisenberg Hamiltonians on bipartite lattices will be discussed using a large -N method. Topological effects produce different spin-Peierls or valence bond solid states depending periodically on the magnitude of the spin, with periodicity given by the co-ordination number of the lattice. If time allows, topological effects and statistics of excitations for other Heisenberg and Hubbard models will also be discussed.
Advances in micro-lens surface metrology: The role of retrace errors

The random ball test is employed for self-calibration of micro-refractive lens measurements. It is shown that interferometer aberrations lead to retrace errors, which are a strong function of test part curvature on the micro-scale.
EFFECT OF A PROGESTIN-ESTROGEN ORAL CONTRACEPTIVE ON BLOOD CLOTTING FACTORS.

Abstract Prothrombin, factor V, factor VIII, factor X and the “prothrombin and proconvertin (P and P)” levels in a series of 41 women who were taking the progestin-estrogen combination, “Ortho-Novum,” were determined; the control series were married women using vaginal contraceptives and young unmarried women. Highly significant increases in the P and P, factor X and prothrombin values were found in the women taking “Ortho-Novum.” In a small double-blind study, factors VII and X and P and P determinations were made in 2 randomly chosen individuals on “Ortho-Novum,” 2 individuals who had recently discontinued oral contraception and 5 normal controls. The highest values in all 3 tests were found in the 2 individuals taking “Ortho-Novum,” and the average value of the 3 determinations in these 2 subjects was significantly higher than in the remaining 8 subjects. The values in the patients who had discontinued the steroids were within normal limits. It is stressed that the observed increases in clotting factors do not necessarily indicate a “hypercoagulable” state if this condition be defined as a condition in which there is an increase over normal in the likelihood of thrombosis.
Characteristic polynomial of the QUEST algorithm

QUEST is a widely-used attitude estimation algorithm that determines three-axis attitude from vector observations. A key step in QUEST as well as many other fast attitude estimation algorithms involves solving the characteristic equation of a four-dimensional symmetric real matrix for the maximum eigenvalue of the matrix using an iterative root-finding method, for example, the Newton-Raphson method. When the attitude is only marginally observable, the form of the characteristic polynomial play a bigger role in the calculation of the maximum eigenvalue. The partially-factorized form of the characteristic polynomial leads to higher accuracy in the calculation of maximum eigenvalue than the expanded form of the characteristic polynomial.
Effect of docosahexaenoic acid (DHA) on arachidonic acid metabolism and platelet function

Studies from our laboratory have suggested a role for ferrous iron in the metabolism of arachidonic acid and demonstrated that inhibitors of prostaglandin synthesis exert their effect by complexing with the heme group of cyclooxygenase. Docosahexaenoic acid (DHA) is a potent competitive inhibitor of arachidonic acid metabolism by sheep vesicular gland prostaglandin synthetase. In this study we have evaluated the effect of exogenously added DHA on platelet function and arachidonic acid metabolism. DHA at 150 microM concentration inhibited aggregation of platelets to 450 microM arachidonic acid. At this concentration DHA also inhibited the second wave of the platelet response to the action of agonists such as epinephrine, adenosine diphosphate and thrombin. Inhibition induced by this fatty acid could be overcome by the agonists at higher concentrations. DHA inhibited the conversion of labeled arachidonic acid to thromboxane by intact, washed platelet suspensions. However, platelets in plasma incubated first with DHA then washed and stirred with labeled arachidonate generated as much thromboxane as control platelets. These results suggest that the polyenoic acids, if released in sufficient quantities in the vicinity of cyclooxygenase, could effectively compete for the heme site and inhibit the conversion of arachidonic acid.
Inhibition by cyanamide of 4-hydroxycyclophosphamide/aldophosphamide oxidation to carboxyphosphamide☆

Abstract The relative rates at which normal and malignant cells oxidize 4-hydroxycyclophosphamide/aldophosphamide to carboxyphosphamide, a reaction catalyzed by NAD-linked aldehyde dehydrogenases and by aldehyde oxidase, may be potentially important in determining the relative sensitivities of these cells to cyclophosphamide. Potential inhibitors of the NAD-linked aldehyde dehydrogenase catalyzed reaction were sought in the present investigation. Pretreatment with cyanamide markedly depressed (70–98 percent) the catalytic activity of NAD-linked aldehyde dehydrogenases present in the 105,000 g soluble fraction and the solubilized 105,000 g particulate fraction of rat and mouse liver and kidney, and of W256 ascites carcinosarcoma cells, when butyraldehyde was used as the substrate. Disulfiram, diethyldithiocarbamic acid or allyl alcohol pretreatment was relatively ineffective. Acrolein or cyclophosphamide pretreatment was without effect. Oxidation of 4-hydroxycyclophosphamide/aldophosphamide to carboxyphosphamide by hepatic soluble and solubilized particulate fractions under incubation conditions optimal for the expression of NAD-linked aldehyde dehydrogenase activity was virtually abolished when the subcellular fractions were obtained from rats or mice treated with cyanamide. Conversion of 4-hydroxycyclophosphamide/aldophosphamide to carboxyphosphamide in vivo was markedly depressed in cyanamide-treated. functionally anephric, mice. Cyanamide should prove to be a useful tool in ascertaining whether the rate of 4-hydroxycyclophosphamide/aldophosphamide oxidation to carboxyphosphamide is an important determinant in the sensitivity of normal and malignant cells to cyclophosphamide.
Stress ulcer prophylaxis in mechanically ventilated patients: integrating evidence and judgment using a decision analysis.

Objective Stress ulcer prophylaxis with a histamine-2 receptor antagonist can reduce the risk of gastrointestinal bleeding in mechanically ventilated patients but may also increase the risk of ventilator-associated pneumonia. We sought to clarify the tradeoffs involved in selecting a prophylactic strategy.
Fixed point approximations for TCP behavior in an AQM network

In this paper, we explore the use of fixed point methods to evaluate the performance of a large population of TCP flows traversing a network of routers implementing active queue management (AQM) such as RED (random early detection). Both AQM routers that drop and that mark packets are considered along with infinite and finite duration TCP flows. In the case of finite duration flows, we restrict ourselves to networks containing one congested router. In all cases, we formulate a fixed point problem with the router average queue lengths as unknowns. Once these are obtained, other metrics such as router loss probability, TCP flow throughput, TCP flow end-to-end loss rates, average round trip time, and average session duration are easily obtained. Comparison with simulation for a variety of scenarios shows that the model is accurate in its predictions (mean errors less than 5%). Last, we establish monotonicity properties exhibited by the solution for a single congested router that explains several interesting observations, such as TCP SACK suffers higher loss than TCP Reno.
Children's use of the yahooligans! web search engine. III. cognitive and physical behaviors on fully self-generated search tasks

This article presents the third part of a research project that investigated the information-seeking behavior and success of seventh-grade science children in using the Yahooligans! Web search engine/directory. In parts 1 and 2, children performed fully assigned tasks to pursue in the engine. In the present study, children generated their tasks fully. Children's information seeking was captured from the cognitive, physical, and affective perspectives using both quantitative and qualitative inquiry methods. Their information-seeking behavior and success on the fully self-generated task was compared to the behavior and success they exhibited in the two fully assigned tasks. Children were more successful on the fully self-generated task than the two fully assigned tasks. Children preferred the fully self-generated task to the two fully assigned tasks due to their ability to find the information sought and satisfaction with search results rather than the nature of the task in itself (i.e., self-generated aspect). Children were more successful when they browsed than when they searched by keyword on the three tasks. Yahooligans! design, especially its poor keyword searching, contributed to the breakdowns children experienced, implications for system design improvement and Web training are discussed.
Determining atmospheric dust concentrations during strong flow perturbations using a digital-optical technique

Dust emissions due to low-level flight of a helicopter are studied as part of the Integrated Desert Terrain Forecasting for Military Operations project. Atmospheric concentrations of PM10 were measured at different heights downwind of the helicopter flight path. Digital video images captured the entrainment and dispersion of the dust plume formed by the wake of the helicopter during each pass down the flight course. The video data are analyzed to relate the dust plume strength to degradation of local visibility. A strong relationship between color changes/standard deviations and plume strength is found. This relationship is used to develop an algorithm that can determine local visibility degradation due to local PM10 concentrations around a helicopter. This algorithm can be combined with concentration output data from an atmospheric dispersion model to simulate visibility in a helicopter simulator.
A 14-bit 20-Msamples/s pipelined A/D converter with class A/B SiGe amplifier

This paper describes a 14-bit 20MSPS switched-capacitor pipelined ADC designed in a complementary SiGe/SOI bipolar process. It features an input-to-output class A/B operational amplifier designed to drive large sampling capacitors of 10pF without consuming excessive power. Prototype implementation exhibits measured INL of +/- 2.0 LSB, DNL of +/- 0.5 LSB, SNR of 73 dB and SFDR of 85 dB with a 2MHz input signal. Analog power dissipation at lowest amplifier bias setting is 390mW with 5V supply.
The Political Process and the Failure of the Child Labor Amendment

Using the proposed Child Labor Amendment of 1924 as an example of family policy, this article analyzes the reasons for its failure to be ratified in a Massachusetts referendum. This failure had much to do with its later nonacceptance in other states. The discussion begins with the Congressional hearings and the arguments for and against the amendment. The following description of the movement for its ratification in the states and the Massachusetts referendum focuses on the factors involved in the outcome of the political process. After a summary of the political campaign leading to the amendment's loss, the article concludes with its implications for present-day family policy initiatives.
T-cell differentiation of human and non-human primate CD34+ hematopoietic progenitor cells using porcine thymic stroma

: Transplantation of swine thymic tissue has been proposed as an approach to reconstitute the immune system of HIV-infected individuals. This is an attractive strategy because miniature swine are readily available as donors and porcine tissue is resistant to infection with HIV-1. Demonstration that porcine thymus tissue supports primate T-cell differentiation is critical to the ultimate utility of this approach. Using a thymic stroma culture system we have previously described [Rosenzweig M, Marks DF, Zhu H et al. In vitro T lymphopoiesis of human and rhesus CD34+ progenitor cells. Blood 1996; 87: 4040], we demonstrate that porcine thymus tissue is able to promote the in vitro T-lymphocyte differentiation of both human and non-human primate hematopoietic progenitor cells. CD34+ hematopoietic progenitors differentiated into both double positive (CD4+CD8+) and single positive thymocytes expressing CD4 or CD8 alone. A polyclonal T-cell repertoire was evident. In addition, the T cells responded appropriately to mitogen and were permissive to infection with simian immunodeficiency virus (SIV). These data demonstrate the ability of porcine thymus to support T-cell differentiation of both human and non-human hematopoietic progenitor cells and support in vivo studies of transplantation of swine thymic tissue as a strategy for immune reconstitution in AIDS.
Role of asymmetric cell division in lifespan control in Saccharomyces cerevisiae

Aging determinants are asymmetrically distributed during cell division in S. cerevisiae, which leads to production of an immaculate, age-free daughter cell. During this process, damaged components are sequestered and retained in the mother cell, and higher functioning organelles and rejuvenating factors are transported to and/or enriched in the bud. Here, we will describe the key quality control mechanisms in budding yeast that contribute to asymmetric cell division of aging determinants including mitochondria, endoplasmic reticulum (ER), vacuoles, extrachromosomal rDNA circles (ERCs), and protein aggregates.
Silences Kept: The Absence of Gender and Sexuality in Black Press Historiography

Approaches to scholarship on the early 20th century black press has marginalized gender and sexuality in the historiography of black newspapers. Historians of black newspapers published between 1910 and 1945, the peak of black newspapers’ popularity, emphasize the political role of the black press. This image has continued to predominate in African American historiography. Scholars have made very little effort to integrate an analysis of gender and sexuality into the work on black newspapers. Consequently, the persistent focus on the political role of the black press has narrowed the definition of “political” in African American historiography and grossly overlooked the value of understanding the black press through its coverage of gender and sexuality.
Chebyshev Semi-Discrete Approximations for Linear Parabolic Problems

Consider the approximate solution of the linear system of ordinary differential equations $$ \left\{ {\begin{array}{*{20}{c}} {\frac{{d\underline {w\left( t \right)} }}{{dt}} = - A\underline w \left( t \right) + \underline r \quad \forall t > 0,} \\ {\underline w \left( 0 \right) = \underline {\tilde{u}} ,} \\ \end{array} } \right. $$ (1) where A is a given n &#x00D7 n Hermitian and positive definite matrix, and where ṟ and ũ are given n-vectors. Such linear systems arise, for example, in the so-called semi-discrete numerical approximations to linear heat-conduction problems in which the spatial variables are suitably differenced, but the time variable is left continuous. The solution of (1) is clearly given by $$ \underline w \left( t \right) = {A^{ - 1}}\underline r + \exp \left( { - tA} \right)\left\{ {\underline {\tilde u} - {A^{ - 1}}\underline r } \right\},\quad \forall t \geqslant 0. $$ (2)
The COMT Val/Met polymorphism is associated with reading related skills and consistent patterns of functional neural activation

In both children and adults there is large variability in reading skill, with approximately 5–10% of individuals characterized as having reading disability; these individuals struggle to learn to read despite adequate intelligence and opportunity. Although it is well established that a substantial portion of this variability is attributed to the genetic differences between individuals, specifics of the connections between reading and the genome are not understood. This article presents data that suggest that variation in the COMT gene, which has previously been associated with variation in higher-order cognition, is associated with reading and reading-related skills, both at the level of brain and behavior. In particular, we found that the COMT Val/Met polymorphism at rs4680, which results in the substitution of the ancestral Valine (Val) by Methionine (Met), was associated with better performance on a number of critical reading measures and with patterns of functional neural activation that have been linked to better readers. We argue that this polymorphism, known for its broad effects on cognition, may modulate (likely through frontal lobe function) reading skill.
Mental models: a theoretical overview and preliminary study

Within the socio-cognitive framework of sense-making, this paper explicates the term 'mental model' and its associated concepts, analyzes the controversies and connections pertaining to mental model research in information studies, and reports the findings of an exploratory study of the mental models of an academic information system. As one aspect of the process of making sense out of their experiences, individuals develop mental models of the systems and processes with which they interact. These models include (1) key components, (2) relationships between those components, and (3) techniques for interacting with the system or process. The small-scale study discussed here identifies three distinct patterns across the models of information seeking held by graduate students in a reference course.
Reexamining the barrier effect of the Tibetan Plateau on the South Asian summer monsoon

Abstract. The Tibetan Plateau has been conventionally treated as an elevated heat source driving the Asian monsoon system, especially for the South Asian monsoon. Numerous model simulations with general circulation models (GCMs) support this hypothesis with the finding that the Asian monsoon system is weak or absent when all elevated topography is removed. A recent model simulation shows that the South Asian summer monsoon circulation is little affected with only the Himalayas (no-Tibetan Plateau) kept as a barrier, leading to a hypothesis of the barrier "blocking" mechanism of the Tibetan Plateau. In this paper, a new series of experiments are designed to reexamine this barrier effect. We find that with the barrier, the large-scale summer monsoon circulation over South Asia is simulated in general agreement with the full Tibetan Plateau, which is consistent with the previous finding. However, there remains significant differences in both wind and precipitation fields, suggesting a role for the full Tibetan Plateau as well. Moreover, the proposed barrier blocking mechanism is not found in our experiments. The energy of the low-level air and the convection are lower and weaker over the Indian subcontinent in the full Tibetan Plateau experiment than that in the no-Tibetan Plateau experiment or the barrier only experiment, which is in contrast to the barrier blocking hypothesis. Instead, there is a similar candle-like latent heating in the middle troposphere along the southern edge of the Tibetan Plateau in both the full Tibetan Plateau and the barrier experiments, whereas this "candle heating" disappears in the no-Tibetan Plateau experiment. We propose that this candle heating is the key to understanding the mechanisms of the Tibetan Plateau on the South Asian monsoon. Future studies are needed to check the source of the "candle heating" and its effect on the Asian monsoon.
A new approach to the long-time behavior of self-avoiding random walks

Abstract We study a T step weakly self-avoiding random walk in d > 4 dimensions by treating it as a one-dimensional statistical mechanical system. We use the polymer expansion along with the lace expansion to arrive at an expression for the Fourier-transformed propagator of the self-avoiding walk, valid in some neighborhood of the origin, that up to small edge effects is equal to that of some simple random walk. This yields simple proofs that, as T → ∞, the variance of the endpoint is asymptotically linear in T and the scaling limit of the endpoint is gaussian.
Improved Analytical Estimate of Global CTE Mismatch Displacement in Areal-Array Solder Joints

An analytical expression is derived for determining the maximum solder joint shearing displacement occurring in an a real-array interconnect under global CTE mismatch loading. The result may be viewed as a “load correction factor” to be applied to the commonly used estimate which is based on the free thermal expansion of component and substrate. The new expression for the correction factor includes the following parameters: (a) dimensions and material properties of component and substrate; (b) array size and population; (c) material properties of solder; and (d) geometric parameters of the individual joints. The theoretical result is based on modeling the assembly as two circular elastic disks connected by a shear-type “elastic foundation” whose distributed shear stiffness is related to the joint/array characteristics. The analytical expression and the graphical aids presented herein may provide convenient alternatives to performing time-consuming and expensive finite element “macro-analyses” on the assembly for the purpose of specifying boundary conditions for a subsequent “micro-analysis” on a single joint.
Geiger-Mode Operation of Ge-on-Si Avalanche Photodiodes

Single-photon detection is reported for Ge-on-Si separate-absorption-charge-multiplication avalanche photodiodes. Single-photon detection efficiency of 14%, dark count rate of 108 s-1, and timing resolution of 117 ps were achieved.
Discrimination learning in adult bobwhite quail fed paraquat

Adult male bobwhite quail (Colinus virginianus) were fed a diet containing 0, 25 or 100 ppm paraquat dichloride. After 60 d on treated diets, discrimination learning was evaluated with acquisition and reversal tests. The three groups performed similarly on these tests. Dose-related histopathological lesions were not found in liver, kidney or lung tissues.
Up, Down, Over, Under: Spatial Relationship Words.

A series of workable techniques that help LD children understand and read spatial relationship words
Impact of Introduced Rough Shiner (Notropis baileyi) on the Native Fish Community in the Chattahoochee River System

Abstract Historical and contemporary fish collection data were used to compare the relative abundance of introduced rough shiner (Notropis baileyi) in the Chattahoochee River (Halawakee and Mountain Oak creeks) to native populations in the Tallapoosa River and to examine the effect of the introduction on the native Chattahoochee River fish community. Absent during the 1981–1985 survey of Mountain Oak Creek, the rough shiner was the fourth most abundant species (10.5% of catch) taken in 1995. In Halawakee Creek mean relative abundance of rough shiner increased from 9.8% in 1971 to 19.8% in 1995. The rough shiner was not collected above the milldam in Halawakee Creek during the historical and contemporary surveys. The rough shiner tended to be more abundant in Halawakee Creek than in its native Tallapoosa River (t = −2.11; df = 11; P = 0.06), where species richness is higher. In Mountain Oak Creek, blacktip shiner (Lythrurus atrapiculus) and golden shiner (Notemigonus crysoleucas) were abundant historically...
Hurricane disturbance in a temperate deciduous forest: patch dynamics, tree mortality, and coarse woody detritus

Patch dynamics, tree injury and mortality, and coarse woody detritus were quantified to examine the ecological impacts of Hurricane Fran on an oak-hickory-pine forest near Chapel Hill, NC. Data from long-term vegetation plots (1990–1997) and aerial photographs (1998) indicated that this 1996 storm caused patchy disturbance of intermediate severity (10–50% tree mortality; Woods, J Ecol 92:464–476, 2004). The area in large disturbance patches (>0.1 ha) increased from 10 cm dbh was 18%. The basal area of standing dead trees after the storm was 0.9 m2/ha, which was not substantially different from the original value of 0.7 m2/ha. In contrast, the volume and mass of fallen dead trees after the storm (129 m3/ha; 55 Mg/ha) were 6.1 and 7.9 times greater than the original levels (21 m3/ha; 7 Mg/ha), respectively. Uprooting was the most frequent type of damage, and it increased with tree size. However, two other forms of injury, severe canopy breakage and toppling by other trees, decreased with increasing tree size. Two dominant oak species of intermediate shade-tolerance suffered the largest losses in basal area (30–41% lost). Before the storm they comprised almost half of the total basal area in a forest of 13% shade-tolerant, 69% intermediate, and 18% shade-intolerant trees. Recovery is expected to differ with respect to vegetation (e.g., species composition and diversity) and ecosystem properties (e.g., biomass, detritus mass, and carbon balance). Vegetation may not revert to its former composition; however, reversion of biomass, detritus mass, and carbon balance to pre-storm conditions is projected to occur within a few decades. For example, the net change in ecosystem carbon balance may initially be negative from losses to decomposition, but it is expected to be positive within a decade after the storm. Repeated intermediate-disturbance events of this nature would likely have cumulative effects, particularly on vegetation properties.
Indolo[3, 2-b]carbazole: a Dietary-Derived Factor That Exhibits Both Antiestrogenic and Estrogenic Activity

Background Indole-3-carbinol (I3C) and related compounds have been identified in vegetables of the Brassica genus. I3C and its acid-derived condensation product, indolo[3,2-b]carbazole (ICZ), bind to the aryl hydrocarbon (Ah) receptor and induce CYP1A1/1A2 gene expression in both in vivo and in vitro models. I3C also inhibits mammary tumor development in rodent models. Purpose The major focus of this study was to investigate the induction of CYP1A1-dependent activity and antiestrogenic effects of ICZ in the MCF-7 human breast cancer cell line and determine if induction of CYP1A1 is required for observed antiestrogenic responses. Methods The induction of CYP1A1 in MCF-7 cells was determined by measuring time- and concentration-dependent changes in ethoxyresorufin O-deethylase (EROD) activity in response to ICZ treatment. The effects of ICZ on occupied nuclear estrogen receptor (ER) levels and inhibition of estrogen (17 beta-estradiol [E2])-induced cell proliferation, [3H]thymidine uptake, secretion of the 52-kd protein, and nuclear progesterone receptor (PR) levels were also measured. Chloramphenicol acetyl transferase (CAT) activity was assayed in MCF-7 cells transiently transfected with an estrogen-responsive vit-CAT plasmid. Competitive binding to rat cytosolic ER was also examined. Results ICZ (> or = 10 nM) induced CYP1A1 in MCF-7 human breast cancer cells. This compound also elicited a diverse spectrum of antiestrogenic responses, including inhibition of E2-induced cell proliferation, [3H]thymidine uptake, occupied nuclear PR binding, and CAT activity in cells transfected with the estrogen-responsive vit-CAT plasmid. In nuclear extracts from ICZ-treated cells, there was a decrease in ER levels and binding to an estrogen-responsive element in a gel shift assay. I3C also decreased nuclear ER binding in MCF-7 cells. ICZ bound with low affinity to the ER and exhibited weak estrogen-like activity. Conclusions Like other Ah receptor agonists, ICZ is antiestrogenic in human breast cancer cells, and this activity is consistent with the inhibitory activity of I3C on mammary tumor formation in rodents. ICZ-induced antiestrogenic responses can be observed at times or concentrations in which EROD activity is unchanged, indicating an interaction between the Ah receptor and ER-mediated endocrine pathways that is independent of P450-induced hormone metabolism. ICZ also is a weak estrogen in MCF-7 cells and binds to the ER. Implications The current focus on the role of dietary and environmental estrogens in human disease should take into account the possible contra-active effects of Ah receptor agonists such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), ICZ, I3C, and related compounds that exhibit antiestrogenic activity.
Relationship between medical student perceptions of mistreatment and mistreatment sensitivity

Background: National statistics reveal that efforts to reduce medical student mistreatment have been largely ineffective. Some hypothesize that as supervisors gain skills in professionalism, medical students become more sensitive. Aims: The purpose of this study was to determine if medical student perceptions of mistreatment are correlated with mistreatment sensitivity. Method: At the end of their third year, 175 medical students completed an Abuse Sensitivity Questionnaire, focused on student assessment of hypothetical scenarios which might be perceived as abusive, and the annual Well-Being Survey, which includes measurement of incident rates of mistreatment. It was hypothesized that those students who identified the scenarios as abusive would also be more likely to perceive that they had been mistreated. Results: Student perceptions of mistreatment were not statistically correlated with individual’s responses to the scenarios or to a statistically derived abuse sensitivity variable. There were no differences in abuse sensitivity by student age or ethnicity. Women were more likely than men to consider it ‘‘harsh’’ to be called incompetent during rounds ( p5 0.0005). Conclusion: This study provides preliminary evidence that challenges the hypothesis that medical students who perceive mistreatment by their superiors are simply more sensitive.
Modeling biocomplexity - actors, landscapes and alternative futures

Increasingly, models (and modelers) are being asked to address the interactions between human influences, ecological processes, and landscape dynamics that impact many diverse aspects of managing complex coupled human and natural systems. These systems may be profoundly influenced by human decisions at multiple spatial and temporal scales, and the limitations of traditional process-level ecosystems modeling approaches for representing the richness of factors shaping landscape dynamics in these coupled systems has resulted in the need for new analysis approaches. New tools in the areas of spatial data management and analysis, multicriteria decision-making, individual-based modeling, and complexity science have all begun to impact how we approach modeling these systems. The term ''biocomplexity'' has emerged as a descriptor of the rich patterns of interactions and behaviors in human and natural systems, and the challenges of analyzing biocomplex behavior is resulting in a convergence of approaches leading to new ways of understanding these systems. Important questions related to system vulnerability and resilience, adaptation, feedback processing, cycling, non-linearities and other complex behaviors are being addressed using models employing new representational approaches to analysis. The complexity inherent in these systems challenges the modeling community to provide tools that capture sufficiently the richness of human and ecosystem processes and interactions in ways that are computationally tractable and understandable. We examine one such tool, EvoLand, which uses an actor-based approach to conduct alternative futures analyses in the Willamette Basin, Oregon.
Corcoran on Aristotle’s Logical Theory

Jan Łukasiewicz, by his own account, entered the lists in 1923 as an interpreter of ancient logic from the standpoint of modern formal logic. In that year he began defending his view of the contrast of Stoic logic with Aristotelian logic; this view appeared in print for the first time in 1930.1 This was followed by the Polish version in 1934, and the German in 1935, of his landmark paper, ‘On the History of the Logic of Propositions’ [9]. During the same period Łukasiewicz was lecturing on Aristotle’s syllogistic. An authorized version of his lectures on this and other logical topics was published by students at the University of Warsaw in 1929, republished in Warsaw in 1958, and finally translated into English in 1963 under the title Elements of Mathematical Logic [7]. Łukasiewicz elaborated his researches until he issued in 1951 his now famous monograph Aristotle’s Syllogistic from the Standpoint of Modern Formal Logic. A second edition, enlarged but not revised, appeared in 1957, its author’s death having occurred in the previous year [6].
Theories of civil society and Global Administrative Law: the case of the World Bank and international development

For over two decades, the concept of civil society has informed institutional design in the international realm. Empowering civil society has served as a key rhetorical and policy response to the criticism that the social and economic processes of globalization and the international organizations that have emerged to govern the global realm are illegitimate, elite driven, and anti-democratic. This chapter, which appears in the Elgar Research Handbook on Global Administrative Law, unpacks the concept of civil society with the aim of understanding the institutional reforms that have been undertaken in one important area of global governance — the international development law of the World Bank and other multilateral development banks. The chapter identifies five lines of theoretical argument in favor of civil society: liberal, social capital, multicultural, cosmopolitan, and effective governance. It then canvasses the evolving law of the World Bank, with reference where relevant to other multilateral development banks. The chapter demonstrates that the reforms undertaken in the 1990s — analytical and participation requirements in project planning and funding for civil society groups — were motivated by the social capital and multicultural theories. By contrast, the reforms of the 2000s — transparency and consultation — were driven by the liberal and effective governance theories. Surprisingly, cosmopolitan theories that posit transnational associations as representatives of a global people are largely absent from the law of the World Bank.
Seasonal variation in the secondary chemistry of foliar and reproductive tissues of Delphinium nuttallianum

Abstract Plant secondary compounds are critical in affecting interactions between plants and their herbivores. The norditerpene alkaloids are secondary compounds in Delphinium (larkspur) species which are divided into two classes: the N -(methylsuccinimido) anthranoyllycoctonine (MSAL-type) and non MSAL-type, and are known to be toxic to herbivorous insects and livestock. Alkaloid concentrations were measured in a whole plant context in vegetative and reproductive tissues in Delphinium nuttallianum at different stages of plant maturity at two locations to explore how plant maturity affected alkaloid concentrations within a growing season. Alkaloid concentrations differed between vegetative and reproductive tissues, with vegetative tissues having significantly lower alkaloid concentrations than reproductive tissues. However, no systematic differences in alkaloid concentrations were observed at different plant maturity stages across the growing season. Based on the data we suggest that alkaloid allocation in different plant parts of D. nuttallianum is influenced by life history of the plant, consistent with plant defense theory. At one location, as pods mature the qualitative alkaloid composition changed through structural diversification of the alkaloids present. The ecological significance of this structural diversification awaits further exploration.
Another Article About Standing

This Essay, prepared for a roundtable conference of administrative law scholars, considers the implications of the Supreme Court’s most recent standing decision, Clapper v. Amnesty International, for claims alleging risk-based, or “probabilistic,” injury. Three years before Clapper, in Geertson Seed Farms v. Monsanto, the Court seemed to open the door to such claims by testing the plaintiff’s claim of imminent injury against a test that required the plaintiff to show a “substantial risk” of injury. By contrast, Clapper applied a tougher-sounding test, requiring the plaintiffs in that case to show that their injury was “certainly impending.” Nevertheless, the Court conceded that in the recent past it had applied the “substantial risk” test.The ambiguity caused by Clapper matters because modern regulatory styles – shorthanded here as “New Governance” – often aim at reducing risks of harm to the public. Indeed, such regulation often attempts to attain that goal not through command-and-control regulation, but instead by incentivizing parties to act in ways that mitigate such risks. Both of these characteristics of New Governance regulation make it more likely that regulatory beneficiaries complaining of government mis-regulation will assert probabilistic injury claims. Clapper, by casting at least some doubt on the viability of such claims, thus threatens the availability of judicial review to hold government to account when it commits such errors.This Essay argues that Clapper leaves standing doctrine at least theoretically receptive to these types of injury claims. First, the Court expressly conceded that it has applied the “substantial risk” test in the past – it did not reject that precedent. Second, its explanation of why the plaintiffs before it lacked imminent injury leaves the door open for Congress and administrative agencies to create rights that take the form of increased probabilities for good regulatory outcomes. In turn, the deprivation of such probability-based rights constitutes Article III injury. The Essay notes that, twenty years ago, Justice Kennedy wrote an influential concurring opinion in a major standing case, Lujan v. Defenders of Wildlife, in which he recognized congressional power both to create innovative causes of action and to articulate chains of causation that courts might not otherwise recognize. If the Court remains faithful to Justice Kennedy’s statement – which has significant force given his status as the fifth vote for the standing analysis in Defenders – it should be receptive to probabilistic injury claims when Congress or administrative agencies regulate in a New Governance style.
Irrigation Management for Salt Control

Reinterpretation of crop tolerance data to salinity, chemical precipitation, and dissolution phenomena in soils and soil water flow principles leads to an irrigation water management concept that permits substantial reduction in the amount of salt discharged from irrigation projects. The use of frequent and uniformly applied irrigations, tailored to meet a low but sufficient leaching requirement, provides a means toward minimizing the adverse effects of irrigation on downstream water quality, while maintaining a viable irrigation agriculture.
Investigating the security and digital forensics of video games and gaming systems: A study of PC games and PS4 console

As video games received rapidly increasing attention, modern video games are often concerned with security and privacy issues. Many such video games and game console systems graciously allow player customization, giving people with malicious intent a new vector to lunch security attacks and exchange secretive messages, which posts new challenges to the society of security and digital forensics. In this research, we investigate the security of four popular PC video games and the Sony PlayStation 4 (PS4) game console. Our study showed that each of these video games has at least one feature that may possibly be exploited by attackers for transmitting secretive information, which is very difficult to be detected using current forensic tools. As for gaming consoles, the hard drive of PS4 console is encrypted and consequently most part of its file system cannot be analyzed using current forensic tools such as AccessData's Forensic Toolkit (FTK). However, it is still possible to lunch Denial of Service (DoS) and ARP cache poisoning attacks to the console, which may slow down and halt the system and potentially expose security sensitive information. Based on the above findings, we offer recommendations on how and where security professionals and digital investigators may search for hidden data.