cssi/SciSciGPT-SciSciNet huggingface dataset:
Morphological and cytoskeletal changes in epithelial cells occur immediately upon interaction with Salmonella typhimurium grown under low‐oxygen conditions

Salmonella typhimurium grown under oxygen-limiting conditions were found to enter into, elicit actin filament rearrangement in, and effect morphological changes upon HEp-2 cells within 15 min after infection. Video microscopy revealed that host cell morphological changes associated with entry began within 1 min of productive adherence. Polarized Caco-2 cell morphology was affected 40 s after infection with low-oxygen-grown S. typhimurium. Stationary-phase S. typhimurium did not elicit these phenomena within this time-period even when adherence was enhanced with the afimbial adhesin, AFA-I. Thus, environmental cues regulate S. typhimurium invasion factors, allowing for immediate entry into host cells. Additionally, actin filament rearrangement and morphological changes in the eukaryotic host cell are essential for entry and occur within minutes of infection.
Efficient Reconstruction of Random Multilinear Formulas

In the reconstruction problem for a multivariate polynomial f, we have black box access to $f$ and the goal is to efficiently reconstruct a representation of $f$ in a suitable model of computation. We give a polynomial time randomized algorithm for reconstructing \emph{random} multilinear formulas. Our algorithm succeeds with high probability when given black box access to the polynomial computed by a random multilinear formula according to a natural distribution. This is the strongest model of computation for which a reconstruction algorithm is presently known, albeit efficient in a distributional sense rather than in the worst-case. Previous results on this problem considered much weaker models such as depth-3 circuits with various restrictions or read-once formulas. Our proof uses ranks of partial derivative matrices as a key ingredient and combines it with analysis of the algebraic structure of random multilinear formulas. Partial derivative matrices have earlier been used to prove lower bounds in a number of models of arithmetic complexity, including multilinear formulas and constant depth circuits. As such, our results give supporting evidence to the general thesis that mathematical properties that capture efficient computation in a model should also enable learning algorithms for functions efficiently computable in that model.
Allometric scaling of isokinetic peak torque: the Nebraska Wrestling Study.

Allometric scaling has been used increasingly in the exercise sciences to control statistically for body size differences in physical performance variables. The purpose of this study was to use multivariate allometric scaling to examine the influence of fat-free mass (FFM) on age-related differences in strength in young club (8–13 years) and high-school (14–18 years) wrestlers. The dependent variables were log-transformed values of isokinetic peak torque for leg extension and flexion at 0.52, 3.14, and 5.24 rad · s−1 (30, 180, and 300 · s−1). The independent variables used in the multiple regression analyses were log-transformed values for FFM, age, and the FFM versus age interaction. The resulting regression equations were of the form: log Y = log a + b1 log X1 + b2 log X2 + bn log Xn. The initial multiple regression analyses showed significant interaction effects (P < 0.05) for all dependent variables, therefore separate regression analyses were performed for the younger and older groups of wrestlers. The results indicate that for the younger wrestlers there were increases in isokinetic peak torque at all velocities across age after controlling for FFM. The FFM scaling exponents ranged from 0.94 to 1.31. All exponents included 1.0 in the 95% confidence interval, except for extension at 3.14 rad · s−1. For the high-school wrestlers, both FFM and age were significant for the extension data, but only FFM was significant for the flexion data. All FFM exponents included 1.0 in the 95% confidence interval. These results indicate that the relationship between FFM and peak torque differed across age. In addition, with the exception of the flexion data for the high-school wrestlers, within each group increases in isokinetic peak torque occurred across age, independent of increases in FFM. The causes of the age effect for strength are speculative, but it may be due to developmental changes in neuromuscular function, alterations in the distribution of muscle mass as a percentage of FFM and/or the distribution of FFM across body segments.
Identity and Government Funding in Christian Nonprofits

Objectives. This article aims to understand if and how the expressed religious identity of Christian nonprofit organizations varies between those receiving and not receiving government funding and whether there is evidence that government funding produces such differences. Methods. I utilize a content analysis of narratives provided on tax forms of 1,900 of the largest national and international Christian nonprofits based in the United States. Results. Christian nonprofits receiving government funding are less likely to express a religious identity and tend to use more inclusive language when doing so. However, receiving government funding does not seem to be the direct cause of changes in expressed religious identity. Conclusions. Differences in expressed religious identity might better be understood as the result of long-term changes that both alter the organization's identity and makes it more likely to acquire government funding.
A Fast Electron Gun for Study of Atomic Decays

A fast electron gun with subnanosecond rise and decay times and 100 mA peak beam current has been developed for delayed coincidence studies of atomic decays. The gun is fabricated from an inexpensive tetrode Nuvistor, involving only slight modification.
Polyadenylic acid-containing RNA from rat brain synaptosomes.

— Synaptosomal RNA of rat brain was labelled in vivo by intracranial injection of tritiated uridine. The change in the specific activity of this material with time was similar to that of polysomal RNA. The percent of the radioactive synaptosomal RNA which bound to oligo(dT)-cellulose columns decreased with time after intracranial labelling. The percent of the total synaptosomal RNA which bound to oligo(dT)-cellulose was greater than that of polysomes. The length of the polyadenylate (poly(A)) sequence of synaptosomal RNA was approximately one-half that of polysomal RNA, and about the same as that from mitochondria. Investigation of synaptosomal RNA using sucrose gradients and polyacrylamide gel electrophoresis indicated that there were several distinct species present, and that they were similar to those from the mitochondria. The poly(A)-containing RNA isolated from synaptosomes stimulated the incorporation of radioactive leucine into TCA-precipitable material in a cell-free protein synthesis system. Isolation of RNA from subsynaptosomal components indicated that most, if not all, of the synaptosomal messenger activity was localized in the synaptic mitochondria.
Temporal Behavior of Electron Distributions in an Electric Field

Coefficients are derived for a one-dimensional Fokker-Planck equation describing the evolution of an electron energy distribution. These coefficients include acceleration of electrons between collisions in addition to the collision terms. The coefficient for the average rate of change of the electron energy, $\frac{〈\ensuremath{\Delta}\ensuremath{\epsilon}〉}{\ensuremath{\Delta}t}$, is the same as obtained with the "average-electron" theory; but the expression for the dispersion, $\frac{〈{(\ensuremath{\Delta}\ensuremath{\epsilon})}^{2}〉}{\ensuremath{\Delta}t}$, has not appeared previously.
Nicotinic and muscarinic acetylcholine receptors shape ganglion cell response properties

The purpose of this study was to evaluate the expression patterns of nicotinic and muscarinic ACh receptors (nAChRs and mAChRs, respectively) in relation to one another and to understand their effects on rabbit retinal ganglion cell response properties. Double-label immunohistochemistry revealed labeled inner-retinal cell bodies and complex patterns of nAChR and mAChR expression in the inner plexiform layer. Specifically, the expression patterns of m1, m4, and m5 muscarinic receptors overlapped with those of non-α7 and α7 nicotinic receptors in presumptive amacrine and ganglion cells. There was no apparent overlap in the expression patterns of m2 muscarinic receptors with α7 nicotinic receptors or of m3 with non-α7 nicotinic receptors. Patch-clamp recordings demonstrated cell type-specific effects of nicotinic and muscarinic receptor blockade. Muscarinic receptor blockade enhanced the center responses of brisk-sustained/G4 On and G4 Off ganglion cells, whereas nicotinic receptor blockade suppressed the center responses of G4 On-cells near the visual streak but enhanced the center responses of nonstreak G4 On-cells. Blockade of muscarinic or nicotinic receptors suppressed the center responses of brisk-sustained Off-cells and the center light responses of subsets of brisk-transient/G11 On- and Off-cells. Only nicotinic blockade affected the center responses of G10 On-cells and G5 Off-cells. These data indicate that physiologically and morphologically identified ganglion cell types have specific patterns of AChR expression. The cholinergic receptor signatures of these cells may have implications for understanding visual defects in disease states that result from decreased ACh availability.
Chesapeake Bay Plume Morphology and the Effects on Nutrient Dynamics and Primary Productivity in the Coastal Zone

To determine the effects of the Chesapeake Bay outflow plume on the coastal ocean, nutrient concentrations and climatology were evaluated in conjunction with nitrogen (N) and carbon (C) uptake rates during a 3-year field study. Sixteen cruises included all seasons and captured high- and low-flow freshwater input scenarios. Event-scale disturbances in freshwater flow and wind speed and direction strongly influenced the location and type of plume present and thus the biological uptake of N and C. As expected, volumetric primary productivity rates did not always correlate with chlorophyll a concentrations, suggesting that high freshwater flow does not translate into high productivity in the coastal zone; rather, high productivity was observed during periods where recycling processes may have dominated. Results suggest that timing of meteorological events, with respect to upwelling or downwelling favorable conditions, plays a crucial role in determining the impact of the estuarine plume on the coastal ocean.
Effects of reduced tillage, resistant cultivars, and reduced fungicide inputs on progress of early leaf spot of peanut (Arachis hypogaea)

Field experiments were conducted in 2000 and 2001 on Georgia Green, Florida MDR-98, and C-99R peanut (Arachis hypogaea) cultivars in Tifton, GA, to determine the effects of tillage practices on early leaf spot (Cercospora arachidicola) epidemics under standard fungicide regimes and fungicide regimes with fewer applications. Leaf spot epidemics were suppressed in reduced tillage (strip-till) plots compared with conventional tillage plots and were suppressed in MDR-98 and C-99R cultivars compared with the standard runner-type cultivar, Georgia Green. Within tillage and cultivar combinations, leaf spot intensity typically was lower in plots treated with fungicides at standard intervals (seven total applications) than in those treated at extended intervals (four total applications). However, in most cases, leaf spot control in extended interval treatments in the strip-till system was comparable to that in the standard interval treatments in conventional tillage. Based on these results, the number of fungicide applications could be reduced without compromising control of leaf spot when reduced tillage is used, especially if combined with moderately resistant cultivars. Suppression of leaf spot epidemics in the strip-till plots did not coincide with higher yields in either year. In 2001, yields were lower in strip-till plots than in conventional tillage plots. Yields were typically higher in the cultivar C-99R than in Georgia Green, regardless of the tillage treatment.
Electroluminescent and Electrical Characteristics of Polar and Nonpolar InGaN/GaN Light-Emitting Diodes at Low Temperature

Three types of InGaN multiple quantum-well light-emitting diodes (LEDs) were subjected to electroluminescent and electrical characterization at low temperatures and results were compared. Characterized samples included (0001) c-plane InGaN LEDs, (1120) a-plane InGaN LEDs, and AlInGaP LEDs. While electroluminescence from the (1120) InGaN LEDs and AlInGaP LEDs extinguished and became highly electrically resistive at low temperature, the (0001) InGaN LEDs emitted light down to 7 K. This result suggested the continued presence of electrical carriers in the (0001) InGaN LEDs at low temperatures. A carrier-generation mechanism is proposed by examining the energy band diagram with polarization-induced internal electric fields taken into account. Polarization fields in the (0001) InGaN LEDs give rise to local field emission, hole-trapping potential, and interface states, which assist hole injection. It is believed that (0001) InGaN LED operation was possible at low temperatures because of these effects.
Therapeutic Applications of Online Gaming

ABSTRACT This article discusses online gaming in the twenty-first century, describes online gaming, considers negative and positive aspects of gaming, and proposes several possible research, practice, and educational strategies for subsequent development of this genre into a useful tool for human service interventions. Positive characteristics of online gaming environments such as high levels of social interaction and the potential for transformative experiences strongly suggest that many clients will be utilizing such environments. In addition, practitioners must not only learn to assess client use of gaming but also develop the necessary knowledge and skills to utilize online games as therapeutic tools.
A partitioning approach to scaling anomaly detection in graph streams

Due to potentially complex relationships among heterogeneous data sets, recent research efforts have involved the representation of this type of complex data as a graph. For instance, in the case of computer network traffic, a graph representation of the traffic might consist of nodes representing computers and edges representing communications between the corresponding computers. However, computer network traffic is typically voluminous, or acquired in real-time as a stream of information. In previous work on static graphs, we have used a compression-based measure to find normative patterns, and then analyzed the close matches to the normative patterns to indicate potential anomalies. However, while our approach has demonstrated its effectiveness in a variety of domains, the issue of scalability has limited this approach when dealing with domains containing millions of nodes and edges. To address this issue, we propose a novel approach called Pattern Learning and Anomaly Detection on Streams, or PLADS, that is not only scalable to real-world data that is streaming, but also maintains reasonable levels of effectiveness in detecting anomalies. In this paper we present a partitioning and windowing approach that partitions the graph as it streams in over time and maintains a set of normative patterns and anomalies. We then empirically evaluate our approach using publicly available network data as well as a dataset that represents e-commerce traffic.
Modeling Optical Properties of Small Metallic Nanoparticles Based on Density Functional Theory

Optical properties of silver nanoparticles with different diameters are investigated based on the electronic structures of component silver atoms. Within the frame of tight binding method, the local density of states of each silver atom is obtained through a recursive approach that extracts the required information directly from the Hamilton matrix. Then the interaction between the electric field of incident light and electrons in the nanoparticles is simulated to characterize their optical features and the size effects were interpreted according the results.Copyright © 2007 by ASME
The Enigmatic Light Curve of RX J0058.2−7231

We have analyzed over 6 years of MACHO optical photometry and a smaller amount of OGLE-II data for the X-ray/Be star source RX J0058.2-7231, in the Small Magellanic Cloud. The brightness is clearly modulated with a 60 day period. During this period, the light curve shows a rapid brightening by ~0.05 mag and a much slower decline. The amplitude of the brightening increases with wavelength, so that the system is redder in its bright phase. At R and I, there is evidence of a shallow eclipse with a duration of ~0.1P that occurs within the bright portion of the cycle. The 60 day clock most likely represents the orbit of the X-ray source around the Be star. We suggest that the brightening may be related to changes in the Be star's disk at periastron, assuming the neutron star is in an eccentric orbit. There is some evidence that the period may be decreasing at a rate of ~0.01 days per cycle. A single spectrum, taken during the fainter part of the light curve, shows a typical Be star, with emission lines at Hα and Hβ and absorptions at higher Balmer and He I lines. A comparison is made with the LMC X-ray/Be star system A0538-66, which has a highly eccentric orbit.
Perhaps it is time to rethink IBS-D

To the Editor: Diarrhea predominate irritable bowel syndrome (IBS-D) currently constitutes the largest sub-category of IBS causing a significant emotional and economic impact [1]. This entity has b...
The past is not what it used to be: Optimists' use of retroactive pessimism to diminish the sting of failure.

Two studies tested whether optimists regulate moods by making the past seem inevitable in the case of failures. This retroactive pessimism effect on the part of optimists may appear to be particularly ironic and occurred both in response to a variety of imagined situations in comparison with predictions and successes when inevitability was measured on a constrained rating scale (Study 1) and in response to immediately experienced failures on a laboratory task when open-ended probability judgments were assessed (Study 2). The strategy was associated with positive moods for optimists and appears due to a few easily generated external reasons (Study 2). Pessimists did not use this retroactive strategy. Implications for timing of strategies, mental simulations, and hindsight biases are discussed.
Systematic Planning for Using an Online Survey.

This chapter describes the overall planning process for using online surveys in your evaluation and how to choose survey software or a Web host for your evaluation project.
Transcriptional and Posttranslational Regulation of Cre Recombinase by RU486 as the Basis for an Enhanced Inducible Expression System

Genetic studies often require the employment of an inducible expression system, whereby the expression of a particular gene can be regulated by the exogenous administration of an inert ligand. Cre/loxP-based systems have been previously described as the basis for inducible expression systems by exerting site-specific DNA recombination. In our effort to enhance the properties of the RU486-responsive CrePr1 construct, we have developed the dual GLVP/CrePr system, in which RU486 confers activity control at both the transcriptional and the posttranslational level of CrePr1. This was achieved by placing CrePr1 transcriptional regulation under the control of the RU486-sensitive chimeric regulator GLVP. Stable cell lines harboring the dual GLVP/CrePr as well as the single CrePr1 system were developed. Our results indicate that the dually regulated system is highly inducible by RU486 while maintaining minimal basal activity ("leakage"), characteristics that can be employed in the development of transgenic mice in which genetic pathways can be turned on or turned off after exogenous administration of RU486 at physiologically inert doses.
Specific and Diversive Career Exploration During Late Adolescence

The exploration literature suggests that career exploration may be separated into two distinct forms. Diversive career exploration involves learning broadly about the world of work and the self, whereas specific career exploration involves an in-depth investigation focused on aligning one’s perceptions of self and career prospects. The goal of the current study was to validate the structure of career exploration over time as being composed of diversive and specific forms. The study was conducted on a diverse sample of 308 college and work-bound youth, 19—22 years old, who were assessed annually three times. Structural equation modeling was used to test a longitudinal measurement model and the structural relationships corresponding to the noted distinction between the forms of exploration. Associations between exploration and several additional indicators of career development were further assessed. The results support the theoretically derived distinction between diversive and specific career exploration ...
The diffusion of hydrogen in single-crystal germanium☆

Abstract Single-crystal germanium diffusion specimens were prepared by a special process of drilling and crystal growing. The hollow cylindrical specimen was sealed at one end and attached to a mass spectrometer at the other. By surrounding the thin cylinder with hydrogen gas and observing it diffuse through into the mass spectrometer permeation rates and diffusion coefficients were measured in the temperature range of 800 to 910°C. The excellent agreement between diffusion coefficients measured by the “time lag” and decay curve methods indicates that trapping effects by lattice defects were small or non-existent. The activation energy for diffusion is 8.7±0.8 kcal g atom and the heat of solution is 52.8 ± 1.4 kcal g atom. The permeation rate was found to vary as the square root of the gas pressure, which indicates that the hydrogen exists in the germanium lattice as hydrogen atoms or ions.
Cadmium accumulation and metabolism by rat liver parenchymal cells in primary monolayer culture

Abstract Primary cultures of adult rat liver parenchylmal cells, isolated by the collagenase perfusion technique and maintained as a monolayer,l were used to investigate the characteristics of hepatic cadmium accumulation and metabolism. Cadmium accumulation was found to be temperature- and concentration-dependent process that required sulfhydryl groups and was significantly stimulated by the addition of dexamethasome to the medium. Once taken up, cadmium was less available for exit-exchange processes than its biologically required congener, zinc. Moreover, cadmium influx enhanced zinc efflux. While most of the intracellular cadmium was located in the cytosol, its distribution within this fraction was altered with time. Initially the metal was bound to both high molecular weight species (>50 000) and metallothionein. As the incubation period increased, the cytosol concentration of cdmium and the percentage of this metal associated with metallothionein was likewise increased. [3H]Amino acid incorporation studies indicated that the accumulation of cadmium resulted in de novo synthesis of the 1 and 2 forms of metallothionein.
Electron screening in muonic atoms

Screening corrections to the muon binding energies are computed for Pb, Tl, Ba, and O. Available methods of calculation are compared. It is shown that in a broad range of atomic charges and muon states the screening of nuclear charge by the muon is almost complete, and therefore the electron density of the Z-1 element can be used in most applications. The effect of the muon on the electron cloud and the effect of the vacancies in electron shells on the screening corrections are calculated and discussed. The degree of ionization of the electron 1s1/2 orbit is determined by a cascade calculation including repopulation from the 2p shell.
Partitioning Protein Structures into Domains: Why Is it so Difficult?

This analysis takes an in-depth look into the difficulties encountered by automatic methods for domain decomposition from three-dimensional structure. The analysis involves a multi-faceted set of criteria including the integrity of secondary structure elements, the tendency toward fragmentation of domains, domain boundary consistency and topology. The strength of the analysis comes from the use of a new comprehensive benchmark dataset, which is based on consensus among experts (CATH, SCOP and AUTHORS of the 3D structures) and covers 30 distinct architectures and 211 distinct topologies as defined by CATH. Furthermore, over 66% of the structures are multi-domain proteins; each domain combination occurring once per dataset. The performance of four automatic domain assignment methods, DomainParser, NCBI, PDP and PUU, is carefully analyzed using this broad spectrum of topology combinations and knowledge of rules and assumptions built into each algorithm. We conclude that it is practically impossible for an automatic method to achieve the level of performance of human experts. However, we propose specific improvements to automatic methods as well as broadening the concept of a structural domain. Such work is prerequisite for establishing improved approaches to domain recognition. (The benchmark dataset is available from http://pdomains.sdsc.edu).
Jeev: A Low-Cost Cell Phone Application for Tracking the Vaccination Coverage of Children in Rural Communities

Immunization saves millions of lives against vaccine-preventable diseases. Yet, 24 million children born every year do not receive proper immunization during their first year. UNICEF and WHO have emphasized the need to strengthen the immunization surveillance and monitoring in developing countries to reduce childhood deaths. In this regard, we present a software application called Jeev to track the vaccination coverage of children in rural communities. Jeev synergistically combines the power of smart phones and the ubiquity of cellular infrastructure, QR codes, and national identification cards. We present the design of Jeev and highlight its unique features along with a preliminary evaluation of its performance. We plan to pilot test Jeev in a rural population to study its effectiveness and identify socio-cultural issues that may arise in a large-scale deployment.
Source encoding for partially coherent optical processing

A relation between spatial coherence function and source encoding intensity transmittance function is presented. Since the spatial coherence is depending upon the information processing operation, a strictly broad spatial coherence function may not be required for the processing. The advantage of the source encoding is to relax the constraints of strict coherence requirement, so that the processing operation can be carried out with an extended incoherent source. Emphasis of the source encodings and experimental demonstrations are given. The constraint of temperal coherence requirement is also discussed.
Ebola and hantaviruses

Hantavirus pulmonary syndrome (HPS) and Ebola hemorrhagic fever are acute diseases with high mortality rates in humans caused by negative-stranded RNA viruses for which we have no vaccines. These viruses present two very different profiles when their ecology, history, and status as emerging pathogens are considered. This paper will discuss the dynamics of the discovery and emergence of these two viruses in recent epidemics — HPS in the United States and Ebola hemorrhagic fever in Africa — and summarize what is known about these dangerous viruses. Our laboratory became involved with hantaviruses in the summer of 1993 soon after patients began to present in the southwestern United States with an acute febrile disease associated with rapid progression of pulmonary failure and, at times, rapid recovery. The disease, which had a mortality rate of about 50%, began with a prodromal phase, typically lasting 3 or 4 days, characterized by fever, myalgia and malaise. The development of dyspnea signalled the onset of severe pulmonary edema. As fluid entered the lungs, the blood picture changed: there was hemoconcentration with rise in hematocrit; immunoblasts were present, thrombocytopenia and other changes were seen. The Special Pathogens Branch (SPB) of the National Center for Infectious Diseases (NCID) became involved, not because of any preconceived notion about the nature of the etiologic agent, but rather as part of a coordinated effort mounted by NCID, Centers for Disease Control and Prevention (CDC), as well as other federal, state, and local health agencies, to deal with the outbreak. Many CDC staff were involved in this investigation, both in Atlanta and in the field. CDC adopted a policy of testing for virtually every agent that could be imagined as being in any way associated with this disease. Help was sought from investigators outside CDC if they had particular expertise that …
System design and test method for measuring respirator filter efficiency using mycobacterium aerosols

Abstract Recently, the protection of health care workers from tuberculosis-containing aerosols has been the subject of considerable debate. An experimental apparatus and test protocol were developed to measure the collection efficiency of surgical mask and respirator filter media using a microbial aerosol challenge. Mycobacterium chelonae (M. chelonae) , used as a surrogate for Mycobacterium tuberculosis , was generated from liquid suspension using a Collison nebulizer. Upstream and downstream concentrations of viable aerosol particles were measured using Andersen cascade impactors, while total particle concentrations were measured with an aerodynamic particle sizer (APS). A monodisperse polystyrene latex (PSL) sphere aerosol (0.804 μm) was used in separate experiments to measure filter efficiency; concentrations were determined with the APS. The mycobacterial aerosol ranged in size from 0.65 to 2.2 μm when measured with the cascade impactor. A similar size range was found with the APS, yielding a count median diameter of about 0.8 μm. Samples of the mycobacterial aerosol were collected on glass slides, stained M. chelonae , as determined by environmental scanning electron microscope, were found to be rod shaped with an average length of 2 μm and average width of 0.3 μm. To evaluate the apparatus over a range of filter efficiencies (10–100%), different layers of fiberglass filter paper were tested for penetration using a 0.12 μm dioctyl phthalate (DOP) aerosol measured with a light scattering photometer, in addition to the mycobacterial and PSL aerosols. For the range of efficiencies tested it was shown that filter collection of DOP was linearly related to that of both mycobacterial and PSL sphere aerosols ( r 2 = 0.99), demonstrating that an inert aerosol may be used to predict the collection of biological aerosols by such filter media.
Inhibitory effects of superior cervical ganglionectomy on dimethylbenz(a) anthracene-induced mammary tumors in the rat

The role of the pineal in regulating the oncogenic processes was explored in Sprague-Dawley female rats by comparing incidence and growth of mammary tumors in animals subjected to superior cervical ganglionectomy (SCGx) or blinding and anosmia (BAs) with that of intact rats treated with 7–12- dimethylbenz(a)anthracene (DMBA). The surgery was performed at the age of 56 days, 1 day following the administration of the carcinogen. Growth of mammary tumors was studied, and 15 weeks later the rats were sacrificed by decapitation and the activity of the pineal hydroxyindole-O-methyltransferase (HIOMT) was determined. Carcinostatic effects of similar magnitude were present in both SCGx and BAs groups as evident from tendency toward reduced tumor incidence and decreased total tumor mass. Ganglionectomized rats developed significantly smaller numbers of tumors than intact control animals. A trend toward reduced tumor number and increased tumor regression was evident in the BAs group. Although there was no significant difference in tumor volumes among the groups, BAs animals showed a distinct trend toward smaller tumor volumes at the termination of the experiment. Despite similar carcinostatic tendencies, SCGx rats had significantly lower HIOMT activity than BAs animals. The possible existence of multiple carcinostatic mechanisms in BAs and SCGx rats is discussed.
Relation between the levels of mRNA abundance and kinetics of protein synthesis in pseudorabies virus-infected cells

Abstract Virus proteins synthesized by pseudorabies virus-infected cells can be classified into five groups on the basis of the kinetics of their synthesis at various stages of the infective process; virus mRNAs can similarly be classified into four groups. To determine whether the kinetics of synthesis of specific proteins are determined solely by the level of abundance in the cells of their mRNAs, we have compared at various times after infection the relative synthesis of these proteins with the relative abundance of their mRNAs. We have focused on two proteins: the 142K major capsid protein, an early-late protein, and the 136K major DNA binding protein, an early protein. The mRNAs encoding these proteins were identified. The relative abundances of these mRNAs in the cytoplasms of the infected cells were found to be the same as those associated with the polysome fractions. The relative amount of the proteins synthesized by the infected cells at a given stage of the infective process closely reflected the relative amount of the mRNA encoding these proteins that was present in the cells at the stage of the infective process. Most virus mRNA species that are present in the cytoplasm of infected cells were represented on polysomes to approximately an equal extent. Some RNA species were, however, significantly underrepresented under certain conditions in the polysomal fractions. We conclude that whereas the amount of many virus proteins synthesized by the infected cells is determined mainly by the level of the abundance of their mRNAs, additional controls operate in the cells that determine the relative rates of synthesis of some other virus proteins.
Chemotherapeutic Evaluation of a Synthetic Tubulysin Analogue–Dendrimer Conjugate in C26 Tumor Bearing Mice

The tubulysins, first isolated by the Hofle/Reichenbach group from myxobacterial cultures,1 are exceptionally potent cell-growth inhibitors that act by inhibiting tubulin polymerization and thereby induce apoptosis. For this reason, the biosynthesis,2 mechanism,3 and anticancer activity4 of the tubulysins have been intensively investigated. Tubulysin D (Figure 1), the most potent of the tubulysins, has activity that exceeds virtually all tubulin modifiers, and in particular is 20- to 10000-fold more cytotoxic than the important, clinically approved anticancer drugs the epothilones, vinblastine, and paclitaxel.5,6 Unfortunately, the extraordinary activity of the most potent tubulysins poses considerable complications for chemotherapeutic applications due to toxicity against healthy cells and tissues. Moreover, the tubulysins are difficult to obtain in large quantities from the myxobacteria from which they are isolated, and total synthesis routes are prohibitively difficult due to the fragile and complex nature of the most potent of the naturally occurring tubulysins, which incorporate the labile N,O-acetal functionality.7 Consequently, both academia and the pharmaceutical industry have focused on the synthesis and evaluation of simpler and more stable tubulysin analogues.8 Similarly, significant efforts have been directed to prodrug strategies for selective tumor delivery of tubulysin and its analogues in order to minimize toxicity.8q
From design to prototype - Manufacturing STEM integration in the classroom and laboratory

The community and technical college systems possess unique opportunities to showcase the integration of Science, Technology, Engineering, and Math (STEM) programs into cohesive, collective, and collaborative learning environments. It will be shown that involvement from separate disciplines within STEM fields facilitates a learning environment greater than the sum of its individual parts. Critical involvement from industry partners and sponsors will become fundamental when approaching STEM program integration. Furthermore, with the proper selection and utilization of lower-cost educational technology and machinery, the opportunity to emulate a manufacturing paradigm “from design to prototype” presents itself. The fundamental challenge to take theory shown in class, to a fully realizable product, produced in the college laboratory will be examined. In addition, the question will be asked whether the funding necessary to develop a premier STEM-based college laboratory could be within reach of the typical community / technical college budget? And ultimately, a discussion of the hurdles faced to integrate faculty and staff from the separate STEM disciplines into one collaborative unit will be presented.
Relationships between extremes of the Southern oscillation and the winter climate of the Anglo‐American Pacific Coast

Warm and cold events in the central and eastern equatorial Pacific represent the two extreme climatic states of the Southern Oscillation and are related to pronounced winter climate anomalies along the Pacific coast of Anglo-America. Previous research has demonstrated that the Pacific/North American (PNA) pattern may be the typical response of the northern hemisphere winter atmosphere to tropical forcing during warm events. In general, the anomalous flow associated with the PNA pattern raises winter temperatures along the entire length of the Anglo-American west coast. Precipitation is enhanced in the vicinity of the Alaskan panhandle, but is suppressed to the south. During cold event winters, the dominant 700 mb anomaly strongly resembles the PNA pattern, but with a reversed polarity. Most cold event winters are associated with below normal temperatures along the west coast, while precipitation significantly decreases in the Alaskan panhandle and increases to the south. Thus, the climate anomalies experienced along the Anglo-American west coast during cold events are in the opposite sense to those of warm events. Precipitation, and to a lesser extent temperature anomalies, are sensitive to minor fluctuations in the general placement and orientation of the PNA pattern, which in turn are related to shifts in the position of the polar front jet stream and associated storm track. Thus, a number of disparate climate anomalies are possible in the study area during warm event winters, depending upon the positioning of the long-wave pattern over the north Pacific and North America. Although the PNA and ‘reverse PNA’ patterns can occur in any winter, they are significantly more frequent during warm and cold events, respectively, than in other winters. The west coast temperature and precipitation anomalies associated with the PNA (‘reverse PNA’) during warm event (cold event) winters can occur during any winter displaying the PNA (‘reverse PNA’) pattern, regardless of the presence of a warm (cold) event in the equatorial Pacific. A dynamical model is proposed to explain the observed teleconnection between the Anglo-American west coast and cold Southern Oscillation events.
Transport and growth of larval cisco (Coregonus artedi) in the Keweenaw Current region of Lake Superior

Larval cisco (Coregonus artedi) were sampled from Lake Superior off the western coast of the Keweenaw Peninsula (Michigan, USA) to determine if the Keweenaw Current influences their distribution and growth. Bongo net tows were conducted during April–June 2000 from four transects extending from 0.1 to 17 km offshore. For most sampling dates, cisco tended to be slightly more abundant, larger, and older at inshore locations. Later-hatched larvae appeared at the western-most transects first, during which time earlier-hatched larvae disappeared from the study area. This pattern followed what would be expected if larvae were being transported eastward by the prevailing Keweenaw Current. Estimated growth rates were 84% higher for later-hatched compared with earlier-hatched larvae and 25% lower for offshore larvae from the eastern-most transects compared with elsewhere. Accordingly, surface water temperatures partly explained spatial and temporal variations in growth rate. These results indicate that cisco larvae...
Effect of dislocation blocking on fracture behavior of Al and α-Fe: a multiscale study

We use a multiscale approach in which results from atomistic simulations are combined with discrete dislocation (DD) dynamics simulations of crack-tip plasticity. The method is used to study the effects of dislocation blocking on the fracture behavior of α-iron and aluminum. We studied the effects of blocking for distances ranging from 5 nm to 1 mm and find that the fracture resistance is increased with increasing blocking distance. The atomistic and dislocation dynamics simulations show that the blocking of dislocations causes a net decrease in the shear stress projected on the slip plane, preventing further dislocation emission. Semi-brittle cleavage occurs after a certain number of dislocations are emitted, explicitly demonstrating the embrittling effects of dislocation blocking. This effect can contribute to the brittle behavior observed in some nanocrystalline metals.
A Problem‐Based MBA Curriculum The Ohio University Experience

Ohio University’s MBA program is designed accord‐ing to the principals of problem‐based learning. The curriculum has no courses. Rather, it is organized around problems like those the students will encounter after graduation. Pre‐ and post‐program assessments are used to measure changes in knowledge and skills. Students are required to complete a program assignment in a foreign country. The paper describes the process by which Ohio University made the change from a traditional curriculum to a problem‐based curriculum, includes examples of problems, and includes lessons learned during the past decade.
Drug-Induced Ultrastructural Alterations of Striated Muscles

The striated muscle fibers of the heart and of the diaphragm were more severely affected by plasmocid poisoning than were those of the quadriceps. In the three types of muscles, alterations occurred in the mitochondria or myofilaments, but there were significantly quantitative differences. It is concluded that the muscles with the most highly metabolic activity are most susceptible to the toxic effects of the drug.
Evolution of Molybdenum Nitrogenase during the Transition from Anaerobic to Aerobic Metabolism

Molybdenum nitrogenase (Nif), which catalyzes the reduction of dinitrogen to ammonium, has modulated the availability of fixed nitrogen in the biosphere since early in Earth's history. Phylogenetic evidence indicates that oxygen (O2)-sensitive Nif emerged in an anaerobic archaeon and later diversified into an aerobic bacterium. Aerobic bacteria that fix N2 have adapted a number of strategies to protect Nif from inactivation by O2, including spatial and temporal segregation of Nif from O2 and respiratory consumption of O2. Here we report the complement of Nif-encoding genes in 189 diazotrophic genomes. We show that the evolution of Nif during the transition from anaerobic to aerobic metabolism was accompanied by both gene recruitment and loss, resulting in a substantial increase in the number of nif genes. While the observed increase in the number of nif genes and their phylogenetic distribution are strongly correlated with adaptation to utilize O2 in metabolism, the increase is not correlated with any of the known O2 protection mechanisms. Rather, gene recruitment appears to have been in response to selective pressure to optimize Nif synthesis to meet fixed N demands associated with aerobic productivity and to more efficiently regulate Nif under oxic conditions that favor protein turnover. Consistent with this hypothesis, the transition of Nif from anoxic to oxic environments is associated with a shift from posttranslational regulation in anaerobes to transcriptional regulation in obligate aerobes and facultative anaerobes. Given that fixed nitrogen typically limits ecosystem productivity, our observations further underscore the dynamic interplay between the evolution of Earth's oxygen, nitrogen, and carbon biogeochemical cycles. IMPORTANCE Molybdenum nitrogenase (Nif), which catalyzes the reduction of dinitrogen to ammonium, has modulated the availability of fixed nitrogen in the biosphere since early in Earth's history. Nif emerged in an anaerobe and later diversified into aerobes. Here we show that the transition of Nif from anaerobic to aerobic metabolism was accompanied by both gene recruitment and gene loss, resulting in a substantial increase in the number of nif genes. While the observed increase in the number of nif genes is strongly correlated with adaptation to utilize O2 in metabolism, the increase is not correlated with any of the known O2 protective mechanisms. Rather, gene recruitment was likely a response to more efficiently regulate Nif under oxic conditions that favor protein turnover.
Selective inhibition of proteins synthesized from different mRNA species in reticulocytelysates containing L-pyrroline-5-carboxylic acid

L-Pyrroline-5-carboxylic acid is a naturally occurring nonprotein amino acid present in human plasma that changes concentrations with diet. L-pyrroline-5-carboxylic acid inhibited net synthesis of globin in untreated reticulocyte lysates in a dose dependent manner. This inhibition was greater than that observed with equimolar GSSG or NADP+ and was prevented by a NADPH generating system. L-pyrroline-5-carboxylic acid also inhibited net synthesis of proteins from brome mosaic and alfalfa mosaic virus mRNAs to different extents. However, no effect on the translation of the naturally uncapped encephalomyocarditis virus mRNA was observed. In general, mRNAs that are considered strongly competitive, such as alfalfa mosaic virus 2 and 4, were more resistant to this inhibitory process. These results indicate that pyrroline-5-carboxylic acid can initiate a differential effect on proteins synthesized from different mRNA species by an as yet unidentified mechanism.
Replacement of Tyrosine 1251 in the Carboxyl Terminus of the Insulin-like Growth Factor-I Receptor Disrupts the Actin Cytoskeleton and Inhibits Proliferation and Anchorage-independent Growth

Abstract Insulin-like growth factor (IGF)-I signaling through the IGF-I receptor modulates cellular adhesion and proliferation and the transforming ability of cells overexpressing the IGF-I receptor. Tyrosine phosphorylation of intracellular proteins is essential for this transduction of the IGF-I-induced mitogenic and tumorigenic signals. IGF-I induces specific cytoskeletal structure and the phosphorylation of proteins in the associated focal adhesion complexes. The determination of the exact pathways emanating from the IGF-I receptor that are involved in mediating these signals will contribute greatly to the understanding of IGF-I action. We have previously shown that replacement of tyrosine residues 1250 and 1251 in the carboxyl terminus of the IGF-I receptor abrogates IGF-I-induced cellular proliferation and tumor formation in nude mice. In this study, replacement of either tyrosine 1250 or 1251 similarly reduces the cells ability to grow in an anchorage-independent manner. The actin cytoskeleton and cellular localization of vinculin are disrupted by replacement of tyrosine 1251. Tyrosine residues 1250 and 1251 are not essential for tyrosine phosphorylation of two known substrates; insulin receptor substrate-1 and SHC, nor association of known downstream adaptor proteins to these substrates. In addition, these mutant IGF-I receptors do not affect IGF-I-stimulated p42/p44 mitogen-activated protein kinase activation or phosphatidylinositol (PI) 3′-kinase activity. Thus, it appears that in fibroblasts expressing tyrosine 1250 and 1251 mutant IGF-I receptors, the signal transduction pathways impacting on mitogenesis and tumorigenesis do not occur exclusively through the PI 3′-kinase or mitogen-activated protein kinase pathways.