cssi/SciSciGPT-SciSciNet huggingface dataset:
Tumor models in various Drosophila tissues

The development of cancer is a complex multistage process. Over the past few decades, the model organism Drosophila melanogaster has been crucial in identifying cancer-related genes and pathways and elucidating mechanisms underlying growth regulation in development. Investigations using Drosophila has yielded new insights into the molecular mechanisms involved in tumor initiation and progression. In this review, we describe various tumor models that have been developed in recent years using different Drosophila tissues, such as the imaginal tissue, the neural tissue, the gut, the ovary, and hematopoietic cells. We discuss underlying genetic alterations, cancer-like characteristics, as well as similarities and key differences among these models. We also discuss how disruptions in stem cell division and differentiation result in tumor formation in diverse tissues, and highlight new concepts developed using the fly model to understand context-dependent tumorigenesis. We further discuss the progress made in Drosophila to explore tumor-host interactions that involve the innate immune response to tumor growth and the cachexia wasting phenotype. This article is categorized under: Cancer > Genetics/Genomics/Epigenetics Cancer > Stem Cells and Development Cancer > Molecular and Cellular Physiology.
Leadership training as an alternative to neoliberalism: A model for community development

In recent decades, cities have experienced dwindling state resources and growing socioeconomic inequalities—many scholars have identified this change as neoliberalism. Although these changes have g...
Staining and whitening products induce color change in resin composites.

PURPOSE To evaluate color and gloss changes of three different resin composites after staining and whitening. METHODS 57 disc-shaped composite samples were made for each of three resin composite materials [Activa BioActive Restorative (Activa), Filtek Supreme (Filtek), and TPH Spectra (TPH)], producing 19 samples per composite (n=19). Each group of resin samples was divided among four solutions: red wine, coffee, tea, and water (control), producing six samples per staining group (n=6) and one control (n=1). Samples were stained for 40 days for 3 hours/day at room temperature. When not undergoing staining/whitening, samples were stored in DI water at 37°C. Measurements were obtained for color and gloss before staining, after staining, and after whitening. Illuminant source specular component excluded (SCE) and included (SCI), with both CIE L*a*b* and CIE 2000 L*C*h* systems, were obtained with colorimetric measurements. The standard ΔE (total color change) = 3.3 was used as a clinically acceptable value. Stained groups were divided into two groups (n= 9 each) for each whitening product: Opalescence Boost and Opalescence PF. Both were applied according to manufacturer's instructions. RESULTS Staining of all samples consistently showed decreased lightness. Filtek showed the most colorimetric changes, especially with wine, while TPH and Activa composites showed few changes; most changes were with tea. Whitening altogether showed generalized increased lightness. All Activa specimens returned to clinically acceptable levels, but the other two materials tested varied. Gloss was most affected for TPH, followed by Filtek; and gloss improved with Activa groups. Overall, Filtek's color varied most, with Activa and TPH being less. All Activa groups returned to clinically acceptable values. However, multiple TPH and Filtek groups had ΔE> 3.3. Furthermore, TPH had the most gloss changes. Activa composites appeared the most stable under the conditions of this study. CLINICAL SIGNIFICANCE Clinicians should be aware that resin composites can undergo staining from a variety of sources. Some resin composites can return to their original esthetic appearance after using bleaching agents. In addition, staining beverages can affect the gloss of the resin composite.
Section 108 Study Group Releases Report

Over the last three years, a panel of government, academic and information industry experts have been studying the copyright challenges faced by libraries and archives in managing and preserving digital content. On March 31, 2008 the panel, which had been convened by the U.S. Copyright Office as the Section 108 Study Group, released its report recommending an extensive series of changes to Section 108 of the U.S. Copyright Act. Section 108 was created as part of the Copyright Act of 1976 and provides limited copyright exemptions for libraries and archives. While it has been amended periodically over the last 30 years, Section 108 is very complicated and does not adequately address issues like archiving of Web content, preservation of both analog and digital works, and digital delivery of copies. The Study Group was convened to explore these challenges, and make recommendations to the U.S. Copyright Office for changes. This work reviews many of the Group’s recommendations.
Selenocysteine incorporation machinery and the role of selenoproteins in development and health.

Publisher Summary One of the major areas of emphasis has understood the role of selenium in health. Selenium is an essential micronutrient in the diet of mammals, and this element has numerous health benefits. It has roles in cancer and heart disease prevention, inhibiting viral expression, and delaying the progression of AIDS in HIV positive patients. Selenium has been reported to have roles in immune function, male reproduction, mammalian development, and slowing the aging process. This chapter discusses the means by which amino acid selenocysteine (Sec) is biosynthesized and incorporated into protein; the generation of mouse models for elucidating the role of selenoproteins in development and health; the identity and functions of selenoproteins; and the distribution and evolution of the amino acid Sec insertion machinery among eukaryotes. Sec is biosynthesized, unlike the common biosynthetic pathways of the other 20 protein amino acids, on its transfer RNA (tRNA). The machinery for inserting Sec into protein is novel and unique to this amino acid. It is apparent that tremendous effort has been expended in evolution for inserting selenium into protein in the form of Sec as discussed in the chapter.
Computational Complexity, Genetic Programming, and Implications

Recent theory work has shown that a Genetic Program (GP) used to produce programs may have output that is bounded above by the GP itself [1]. This paper presents proofs that show that 1) a program that is the output of a GP or any inductive process has complexity that can be bounded by the Kolmogorov complexity of the originating program; 2) this result does not hold if the random number generator used in the evolution is a true random source; and 3) an optimization problem being solved with a GP will have a complexity that can be bounded below by the growth rate of the minimum length problem representation used for the implementation. These results are then used to provide guidance for GP implementation.
Apoptosis and ROS Detoxification Enzymes Correlate with Cytochrome c Oxidase Deficiency in Mitochondrial Encephalomyopathies

The aim of this work was to investigate in muscle the role of apoptosis and of oxidative stress in mitochondrial disorders with dysfunction of respiratory chain. In patients with cytochrome c oxidase deficiency (COX) we found a variable number of myofibers with apoptotic nuclei that matched with the level of enzymatic reduction and roughly correlated with muscle weakness. In parallel, a positive immunostaining for apoptosis-related proteins and Mn and Cu/Zn superoxide dismutase (SOD) were mostly localized in COX-negative fibers. Moreover, glutathione peroxidase activity was increased in muscles with high number of SOD-positive myofibers and prominent apoptotic features. No signs of apoptosis were observed in patients with deficiencies of complexes I and II and without muscle weakness. These data suggest that apoptosis along with increased ROS production, revealed by anti-oxidant enzymes overexpression, may play an important role in the pathophysiology of mitochondrial diseases associated with COX deficiency.
Abstract NS15: Adult Daughters’ Problems in Caring for Parents

Background: Women provide most of the unpaid care to family members. Transitioning from the role of adult daughter to caregiver can be very stressful and unsettling. Purpose: Guided by Friedemann’s framework of systemic organization , the purpose of this descriptive secondary data analysis was to examine problems reported by adult daughters in the first year of caring for a parent with a stroke. Problems in caring can lead to poor health/ incongruence . Method: An IRB approved randomized controlled trial conducted with 73 adult caregivers in Ohio and Michigan examined the experience of caring for someone with stroke. Open-ended questions were included in bimonthly telephone interviews asking caregivers to recall their problems in caring over the past two weeks. For this secondary data analysis, problems reported by only the adult daughters (n=13) were analyzed during two time periods (0-6 and 7-12 months) using Colaizzi’s rigorous method of content analysis. Results: The first theme of witnessing a parent’s condition centered on the adult daughter recognizing changes in their parents’ health condition and behavior (Friedemann’s process dimension of system maintenance ). This theme was consistently apparent throughout 12-months of caring. The second theme, balancing the challenges of the caregiver role , dealt with the struggles and adaption necessary for her new lifestyle of a caregiver ( system maintenance and individuation ).This theme was noticeable throughout the entire year, but more evident in the second 6-months. The final theme, feeling physically, emotionally, and mentally drained, involved problems associated with the overall exhaustion experienced by adult daughters ( system maintenance ). This theme was seen throughout the 1-year period, but more visible in the first 6-months of caring. Conclusions: The findings provide specific, theory-based themes of the adult daughters’ problems during that year of caring that could lead to incongruence in their lives. The information gleaned may offer nurses and other healthcare providers a clearer picture of the problems these daughters experience, leading to more targeted interventions, increased support, and ultimately improved overall health/ congruence for daughters.
Molecular biology and chemistry of the alternative pathway of complement.

Publisher Summary This chapter presents the proteins of the alternative pathway and their special properties as enzymes, enzyme substrates, and regulators. The participation with the classical pathway components, C5–C9, in membrane attack is considered. The surprising discovery of the activation of the alternative pathway by many systems other than antibody is emphasized along with the key role played by C3 and its component parts. The alternative pathway of complement activation is closely linked to natural resistance to infections. The chapter discusses biological manifestations of alternative pathway activation. This area of research has been facilitated by isolated cytolytic alternative pathway that includes the five proteins of the membrane attack pathway. Thus, antibody-independent killing by the cytolytic pathway of bacterial and animal cells, including virus-infected human cells, is illuminated. The biomedical relevance of the alternative pathway as part of the complement system is unquestionable. Once activated, it can mark particles for phagocytosis, induce killing of nucleated cells or of bacteria, and cause lysis of enveloped viruses or virus-infected cells. It generates biologically active protein fragments, such as Bb, C3a, C3b, and C5a that influence function and behavior of inflammatory cells and cells of the immune system.
Exercise training, glucose transporters, and glucose transport in rat skeletal muscles

It was previously found that voluntary wheel running induces an increase in the insulin-sensitive glucose transporter, i.e., the GLUT4 isoform, in rat plantaris muscle (K. J. Rodnick, J. O. Holloszy, C. E. Mondon, and D. E. James. Diabetes 39: 1425-1429, 1990). The present study was undertaken to determine whether 1) the increase in muscle GLUT4 protein is associated with an increase in maximally stimulated glucose transport activity, 2) a conversion of type IIb to type IIa or type I muscle fibers plays a role in the increase in GLUT4 protein, and 3) an increase in the GLUT1 isoform is a component of the adaptation of muscle to endurance exercise. Five weeks of voluntary wheel running that resulted in a 33% increase in citrate synthase activity induced a 50% increase in GLUT4 protein in epitrochlearis muscles of female Sprague-Dawley rats. The rate of 2-deoxy-glucose transport maximally stimulated with insulin or insulin plus contractions was increased approximately 40% (P less than 0.05). There was no change in muscle fiber type composition, evaluated by myosin ATPase staining, in the epitrochlearis. There was also no change in GLUT1 protein concentration. We conclude that an increase in GLUT4, but not of GLUT1 protein, is a component of the adaptive response of muscle to endurance exercise and that the increase in GLUT4 protein is associated with an increased capacity for glucose transport.
Components of the ice age circulation

The effects of ice age boundary conditions on atmospheric dynamics and regional climate patterns are investigated using four GCM simulations. Particular consideration is given to sea surface temperature-sea ice distribution, the appearance of land ice, and the increased elevation of land ice. It is observed that the ice-age sea surface temperature stabilizes the atmosphere over the oceans, increases the frequency of storm tracking through central North America, and amplifies transient eddy energy without increasing baroclinic generation. It is detected that low-elevation ice generates low pressure over eastern North America and southern Europe in winter, while increasing cloud cover and cooling the land in summer. Elevation of the ice sheets cools the land in winter, further intensifies storms off northeastern North America, induces subsidence warming downstream of the European ice sheets in summer, and increases the transient and stationary eddy energy through increased baroclinicity.
Adhesion of Fusobacterium necrophorum to bovine endothelial cells is mediated by outer membrane proteins

Fusobacterium necrophorum, a Gram-negative anaerobe, is frequently associated with suppurative and necrotic infections of animals and humans. The organism is a major bovine pathogen, and in cattle, the common fusobacterial infections are hepatic abscesses, foot rot, and necrotic laryngitis. The species comprises two subspecies: F. necrophorum subsp. necrophorum and F. necrophorum subsp. funduliforme. Bacterial adhesion to the host cell surface is a critical initial step in the pathogenesis, and outer membrane proteins (OMP) play an important role in adhesion and establishment of certain Gram-negative bacterial infections. The means by which F. necrophorum attaches to epithelial or endothelial cells has not been determined. We evaluated whether OMP of F. necrophorum, isolated from a liver abscess, mediated adhesion to bovine endothelial cells (adrenal gland capillary endothelial cell line). The extent of binding of subsp. necrophorum to the endothelial cells was higher than that of F. necrophorum subsp. funduliforme. Trypsin treatment of bacterial cells decreased their binding to endothelial cells indicating the protein nature of adhesins. Preincubation of endothelial cells with OMP extracted from F. necrophorum decreased the binding of bacterial cells. In addition, binding of each subspecies to endothelial cells was inhibited by polyclonal antibodies raised against respective OMP and the antibody-mediated inhibition was subspecies specific. The western blot analysis of OMP bound to endothelial cells with anti-OMP antibodies showed four OMP of 17, 24, 40 and 74 kDa. We conclude that OMP of F. necrophorum play a role in adhesion of bacterial cells to the endothelial cells.
Local order effects on the dynamics of fluids near the liquid-gas critical point

Abstract Local order effects on the dynamical properties of critical fluids are taken into account by introducing a new slowly varying tensorial quantity which is related to the angular momentum of a group of correlated molecules. The theory is applied to an analysis of ultrasonic and light scattering measurements. The presence of two central Lorentzians is predicted and the properties of the broader Lorentzian are successfully described. A preliminary comparison of the theory with experiment is encouraging.
Neural correlates of memory for odor detection conditioning in adult rats

Abstract Adult male Wistar rats were trained in a simple odor detection task, with peppermint odor serving as either an S+, S− or as a randomly presented odor. Twenty-four hours after the last training session, rats were injected with [ 14 C]2-deoxyglucose and exposed to the odor. Mean relative 2-deoxyglucose uptake to the odor was enhanced in the pars dorsalis of the anterior olfactory nucleus of S+ and S− trained rats compared to controls. In contrast, no differences in uptake were detected in either odor-specific focal regions of the olfactory bulb glomerular layer, the pyriform cortex, or the hippocampus.
Identification and Reduction of Ellagic Acid in Muscadine Grape Juice

The precipitate which forms during storage of clarified and pasteurized Magnolia and Carlos muscadine juices was examined using paper chromatography, HPLC, and ultraviolet, infrared, and mass spectrometries. The methanol washed juice precipitate was identified as ellagic acid. The concentrations of ellagic acid in Magnolia juice treated with polyvinylpolypyrrolidone (PVPP) at 0.12, 0.36, 0.60, 0.84, and 1.08 g/L and gelatin at 0.06, 0.12 and 0.24 g/L were determined. The treatment using 1.08g PVPP/L was most effective in reducing ellagic acid, total phenolics, and juice browning.
Thinking About Things

Analysant les differentes tendances de la facon ordinaire de penser les choses, l'A. examine les presupposes metaphysiques de l'approche naturaliste des objets physiques. Du langage naturel aux proprietes platoniciennes, l'A. compare la these de l'essentialisme mereologique a la modalite de re, ainsi que la theorie des noms propres a celle de la designation rigide.
Centriole ultrastructure and its possible role in microtubule formation in an aquatic fungus.

Serial and individual micrographs of centrioles in developing sporangia of the aquatic phycomycete,Phlyctochytrium irregulare Koch, are presented. The A-C linker, the foot, and the hub of the cartwheel are composed of subunits morphologically similar to those of the triplet tubules. It is suggested that the A-C linker is a locus of microtubule nucleation, and as such, it forms the inner part of a microtubular profile located at the A-C linker. Similar profiles are seen on other parts of the triplet blades. Longitudinal sections of centrioles with spindle and astral microtubules emanating from their walls support the suggestion, and diagrammatic models for microtubule nucleation are presented. A stellate granule with ninefold rotational symmetry is present in the lumen of the cartwheel's hub. The hub shows thirteenfold rotational symmetry and is probably a microtubular structure. The possible role of these components in centriole replication is discussed.
Features of thermals in stable wake and neutral stratifications in the disturbed monsoon boundary layer

Thermals, defined as humidity excesses, seem to exhibit distinct features in the disturbed Indian Monsoon Boundary Layer (BL) depending on whether they occur in the stable wake regions, called S in this study, of tropical squalls, or in the neutral regions of the advancing squalls, called N. The stable S region developed weak but gradually increasing ascending motion in the BL while the N region showed strong upward motion at the top of the surface layer (85 m) decreasing steadily thereafter. Similar differences also appear in the other mean thermal fields such as temperature and humidity.
Safety of dermatologic drugs used in pregnant patients with psoriasis and other inflammatory skin diseases

In patients with psoriasis, there is an increased availability of drugs for treatment. However, there are important questions about drug safety for mothers with psoriasis and their fetuses. Currently, there are limited safety data for many of the medications used. In this article, we review current pregnancy risk information for medications commonly used in the treatment of psoriasis. In addition, a list of teratology information resources is included to help practicing clinicians find up-to-date information regarding the safety of the medications they prescribe.
Cotranslational Stabilization of Sec62/63 within the ER Sec61 Translocon Is Controlled by Distinct Substrate-Driven Translocation Events

The ER Sec61 translocon is a large macromolecular machine responsible for partitioning secretory and membrane polypeptides into the lumen, cytosol, and lipid bilayer. Because the Sec61 protein-conducting channel has been isolated in multiple membrane-derived complexes, we determined how the nascent polypeptide modulates translocon component associations during defined cotranslational translocation events. The model substrate preprolactin (pPL) was isolated principally with Sec61αβγ upon membrane targeting, whereas higher-order complexes containing OST, TRAP, and TRAM were stabilized following substrate translocation. Blocking pPL translocation by passenger domain folding favored stabilization of an alternate complex that contained Sec61, Sec62, and Sec63. Moreover, Sec62/63 stabilization within the translocon occurred for native endogenous substrates, such as the prion protein, and correlated with a delay in translocation initiation. These data show that cotranslational translocon contacts are ultimately controlled by the engaged nascent chain and the resultant substrate-driven translocation events.
L-Arginine restores the depressed cardiac output and regional perfusion after trauma-hemorrhage

Abstract Background: Previous studies indicate that vascular endothelial cell dysfunction occurs early after trauma-hemorrhage and may contribute to further alterations in tissue perfusion and cellular function. Because endothelial cell dysfunction is characterized by the reduced release of nitric oxide (NO) by endothelial constitutive NO synthase (cNOS), we tested the hypothesis that administration of L -arginine (ie, the substrate for cNOS) after trauma and hemorrhage should have beneficial effects on depressed cardiac output and organ blood flow under those conditions. Methods: Rats underwent a laparotomy (ie, trauma induced) and were bled to and maintained at a mean arterial pressure of 40 mm Hg until 40% of maximal shed blood volume was returned in the form of Ringer's lactate solution. The animals were then resuscitated with 4 times the volume of the shed blood in the form of Ringer's lactate solution over 1 hour. L -arginine (300 mg/kg body wt) or saline solution was infused intravenously during the first 15 minutes of resuscitation. Cardiac output and organ blood flow were determined by 85 Sr-microspheres at 1.5 and 4 hours after the completion of resuscitation. Plasma interleukin-6 (IL-6) was determined by bioassay at 4 hours after resuscitation. Results: Cardiac output and blood flow in the kidneys, small intestine, and lungs decreased significantly after hemorrhage and resuscitation. In addition, portal blood flow and total hepatic perfusion were also significantly reduced. Administration of L -arginine at the onset of fluid resuscitation, however, restored the depressed cardiac output and tissue perfusion. Moreover, the up-regulated plasma levels of IL-6 were also attenuated by L -arginine administration. Conclusions: Because the adjuvant use of L -arginine restored the depressed cardiac output and organ blood flow and decreased plasma levels of IL-6, administration of this essential amino acid should be considered as a useful adjunct to fluid resuscitation for improving cardiovascular function in trauma victims. (Surgery 1998;124:394-402.)
Nanodevices: Location of Biomarkers and Reagents within Agarose Beads of a Programmable Nano-bio-chip (Small 5/2011)

The slow development of cost-effective medical microdevices with strong analytical performance characteristics is due to a lack of selective and efficient analyte capture and signaling. The recently developed programmable nano-bio-chip (PNBC) is a flexible detection device with analytical behavior rivaling established macroscopic methods. The PNBC system employs ≈300 μm-diameter bead sensors composed of agarose “nanonets” that populate a microelectromechanical support structure with integrated microfluidic elements. The beads are an efficient and selective protein-capture medium suitable for the analysis of complex fluid samples. Microscopy and computational studies probe the 3D interior of the beads. The relative contributions that the capture and detection of moieties, analyte size, and bead porosity make to signal distribution and intensity are reported. Agarose pore sizes ranging from 45 to 620 nm are examined and those near 140 nm provide optimal transport characteristics for rapid (<15 min) tests. The system exhibits efficient (99.5%) detection of bead-bound analyte along with low (≈2%) nonspecific immobilization of the detection probe for carcinoembryonic antigen assay. Furthermore, the role analyte dimensions play in signal distribution is explored, and enhanced methods for assay building that consider the unique features of biomarker size are offered.
Hydraulically-induced convective solute transport across the rabbit peritoneum.

Hydraulically-induced convective solute transport across the rabbit peritoneum. Transport of solutes during osmotically-induced transperitoneal ultrafiltration is less than would be predicted based upon rates of transperitoneal solute diffusion. Previous workers have hypothesized that osmotically-induced convective solute transport occurs only in small pores at the arteriolar end of peritoneal capillaries, whereas solute diffusion occurs only through large venular pores. We tested this heteroporosity hypothesis in the eviscerated New Zealand White rabbit by determining sieving coefficients (S) for creatinine, p-aminohippurate (PAH) and neutral dextran during hydraulically-induced transperitoneal ultrafiltration (N = 13). A hydraulically-induced driving force directs convective solute transport through the same capillary pores employed for diffusion; therefore S for all solutes should approach unity if the heteroporosity hypothesis is valid. S for creatinine and PAH were respectively 0.72 ± 0.03 and 0.67 ± 0.05, values lower than unity and not different from those previously determined during osmotically induced ultrafiltration. Mean S for dextran were relatively independent of molecular size, ranging from 0.50 at 13 A to 0.40 at 50 A. Thus, dextran S were higher than those previously determined during osmotically induced ultrafiltration yet still less than unity. Control experiments (N = 6) suggested that only surface area and not transport characteristics were altered by evisceration. These observations demonstrate that the heteroporosity hypothesis fails to completely describe both diffusive and convective transport properties of the peritoneum. 1
A conformal mesh-generating technique for the conformal finite-difference time-domain (CFDTD) method

This article presents an efficient conformal-mesh generating technique suitable for the conformal finite-difference time-domain (CFDTD) technique. We describe the mesh generation for different types of objects, including planar structures (patch antennas and microwave circuits), as well as for arbitrary three-dimensional structures created by using AutoCAD, GID, or other commercial solid modelers. The versatility of the mesh-generation tool is illustrated through several examples.
Induction of Mutation in Micrococcus Pyogenes by Chemical Inactivation of Sulphhydryl Groups

Induction of Mutation in Micrococcus Pyogenes by Chemical Inactivation of Sulphhydryl Groups
Responding to AIDS: are there any appropriate development and health policies?

The plausibility of several options is considered in this authors exploration of whether there are any development and health policies appropriate to respond to HIV/AIDS. Biomedical options are inherently limited and it is unlikely that concern about AIDS will stimulate far-reaching changes in development policies. Examining the pluralist and relative natures of programming for health the author suggests that there can never be a common approach to health or any individual health problem such as AIDS. People should therefore face the reality in the context of current political conditions that a group of agencies will not be able to broadly control HIV in all settings. Individuals should instead adopt their own responses to cope with HIV/AIDS and only later coordinate their approaches with those of others. Indeed there may be no solution for HIV and AIDS among the most poor and marginalized. The author stresses that the enemy is not AIDS but the status quo which leads to inequalities in health. HIV is therefore not a cause in its own right but a strong marker for action and concern in development. Some of the responses made by organizations to AIDS are analyzed in relation to broader issues in social and economic development. Emphasis is given to the political nature of health.
Grain alignment in the galactic magnetic field

The linear polarization of light observed in many distant stars, presumably an effect of absorption of starlight by elongated interstellar dust grains, provides a means of mapping the magnetic field lines in our own Galaxy as well as probing the properties of the intervening dust. Processes for grain alignment in the galactic magnetic field are reviewed: evidence is examined for grains being spun up to extremely high (109 Hz) angular frequencies by the recoil of hydrogen recombination on grains, as an essential part of the alignment process. Grain alignment would then be inhibited in regions of grain growth and would be most effective where grain growth is inhibited or reaches saturation.
Potentiation of arachidonic acid release by phorbol myristate acetate in platelets is not due to inhibition of arachidonic acid uptake or incorporation into phospholipids.

Activators of protein kinase C, such as tumor-promoting phorbol esters (e.g., phorbol myristate acetate), mezerein, (-)-indolactam V and 1-oleoyl 2-acetoyl glycerol, potentiate arachidonic acid release caused by elevation of intracellular Ca2+ with ionophores. This action of protein kinase C-activators required protein phosphorylation, and was attributed to enhanced hydrolysis of phospholipids by phospholipase A2 (Halenda, et al. (1989) Biochemistry 28, 7356-7363). Recently Fuse et al. ((1989) J. Biol. Chem 264, 3890-3895) reported that the apparent enhanced release of arachidonate was actually due to inhibition of the processes of re-uptake and re-esterification of released arachidonic acid. They attributed this to loss of arachidonyl-CoA synthetase and arachidonyl-CoA lysophosphatide acyltransferase activities, which were measured in membranes obtained from phorbol myristate acetate-treated platelets. In this paper, we show that phorbol myristate acetate, at concentrations that strongly potentiate arachidonic acid release, does not inhibit either arachidonic acid uptake into platelets or its incorporation into specific phospholipids. Furthermore, the fatty acid 8,11,14-eicosatrienoic acid, a competitive substrate for arachidonyl-CoA synthetase, totally blocks arachidonic acid uptake into platelets, but, unlike phorbol myristate acetate, does not potentiate arachidonic acid release by Ca2+ ionophores. We conclude that the action of phorbol myristate acetate is to promote the process of arachidonic acid release by phospholipase A2.
The Treadmill Test—Where To Stop and What Does It Mean?

The prognostic utility of an exercise ECG test depends upon having an adequate workload to stress the cardiac system. A negative stress test, in which there are no adverse clinical or ECG findings, and in which an adequate workload is achieved, stratifies patients into a low-risk group. The 1997 American Heart Association guidelines imply that any index of workload—heart rate, rate-pressure product, or exercise duration in multiples of resting O 2 consumption (METS)—could be used to indicate that adequate stress was achieved. However, while there is considerable evidence supporting the use of METS as a strong independent prognostic variable, there is less support for the use of rate-pressure product or heart rate. Indeed, there is evidence that a high heart rate at a low workload carries an adverse prognosis. Further research is needed to identify the number of METS achieved that would define an adequate workload. In the meantime, a review of the literature suggests that 7 to 10 METS is a reasonable ballpark figure of the minimum workload in patients with a negative stress test that would imply a favorable outcome.
Probability-based Imputation Method for Fuzzy Cluster Analysis of Gene Expression Microarray Data

Fuzzy clustering has been widely used for analysis of gene expression micro array data. However, most fuzzy clustering algorithms require complete datasets and, because of technical limitations, most micro array datasets have missing values. To address this problem, we present a new algorithm where genes are clustered using the Fuzzy C-Means algorithm, followed by approximating the fuzzy partition by a probabilistic data distribution model which is then used to estimate the missing values in the dataset. Using distribution-based approach, our method is most appropriate for datasets where the data are nonuniform. We show that our method outperforms six popular imputation algorithms on uniform and nonuniform artificial datasets as well as real datasets with unknown data distribution model.
Nonlinearities and Nonstationarities in Stock Returns

This article addresses the question of whether recent findings of nonlinearities in high-frequency financial time series have been contaminated by possible shifts in the distribution of the data. It applies a recursive version of the Brock–Dechert–Scheinkman statistic to daily data on two stock-market indexes between January 1980 and December 1990. It is shown that October 1987 is highly influential in the characterization of the stock-market dynamics and appears to correspond to a shift in the distribution of stock returns. Sampling experiments show that simple linear processes with shifts in variance can replicate the behavior of the tests, but autoregressive conditional heteroscedastic filters are unable to do so.
Predictors and Outcomes of Frequent Emergency Department Users

Objective: To identify predictors and outcomes associated with frequent emergency department (ED) users. Methods: Cross-sectional intake surveys, medical chart reviews, and telephone follow-up interviews of patients presenting with selected chief complaints were performed at five urban EDs during a one-month study period in 1995. Frequent use was defined by four or more self-reported, prior ED visits. Multivariate logistic regression identified predictors of frequent ED visitors from five domains (demographics, health status, health access, health care preference, and severity of acute illness). Associations between high use and selected outcomes were assessed with logistic regression models. Results: All study components were completed by 2,333 of 3,455 eligible patients (67.5%). Demographics predicting frequent use included being a single parent, single or divorced marital status, high school education or less, and income of less than $10,000 (1995). Health status predictors included hospitalization in the preceding three months, high ratings of psychological distress, and asthma. Health access predictors included identifying an ED or a hospital clinic as the primary care site, having a primary care physician (PCP), and visiting a PCP in the past month. Choosing the ED for free care was the only health preference predictive of heavy use. Illness severity measures were higher in frequent visitors, although these were not independently predictive in the multivariate model. Outcomes correlated with heavy use include increased hospital admissions, higher rates of ED return visits, and lower patient satisfaction, but not willingness to return to the ED or follow-up with a doctor. Conclusions: Frequent ED visits are associated with socioeconomic distress, chronic illness, and high use of other health resources. Efforts to reduce ED visits require addressing the unique needs of these patients in the emergency and primary care settings.
Multiwavelength two-dimensional optically controlled phased-array antenna

Multiwavelength optically controlled phased array antenna (MWOCPAA) is demonstrated in both 1D and 2D array system. In 1D MWOCPAA, a programmable dispersion matrix (PDM) implemented using Bragg fiber grating is employed for beam angle control. For 2D MWOCPAA, switching optical delay lines are cascaded with the PDM to form an all-optical hardware compressive architecture. Relative time delays are experimentally measured using a prototype 4 X 2 MWOCPAA with 2-bit X 2-bit resolution. The results agree well with the theoretical prediction.
Impaired Functions of Peripheral Blood Monocyte Subpopulations in Aged Humans

Aging is associated with increased susceptibility to microbial infections, and monocytes play an important role in microbial defense. In this study, we have identified and compared four subpopulations of monocytes (CD14++(high)CD16−, CD14+(low)CD16−, CD14++(high)CD16+, and CD14+(low)CD16+) in the peripheral blood of young and aged subjects with regard to their numbers, cytokine production, TLR expression, and phosphorylation of ERK1/2 in response to pam3Cys a TLR-1/2 ligand. Proportions and numbers of CD14++(high)CD16+ and CD14+(low)CD16+ monocytes were significantly increased, whereas proportions of CD14+(low)CD16− monocytes were decreased in aged subjects as compared to young subjects. In aged subjects, IL-6 production by all four subsets of monocytes was significantly decreased, whereas TNF-α production was decreased in monocyte subsets, except the CD14+(low)CD16− subset. A significantly reduced expression of TLR1 was observed in CD14++(high)CD16+ and CD14+(low)CD16+ monocyte subsets in aged subjects. Furthermore, following pam3Cys stimulation, ERK1/2 phosphorylation was significantly lower in CD14+(low)CD16+, CD14++(high)CD16+, and CD14+(low)CD16− subsets of monocytes from aged subjects. This is the first study of four subpopulations of monocytes in aging, which demonstrates that their functions are differentially impaired with regard to the production of cytokines, expression of TLR, and signaling via the ERK–MAPK pathway. Finally, changes in the number of monocyte subsets, and impairment of TLR1 expression, TNF-α production, and EK1/2 phosphorylation was more consistent in CD16+ monocyte subsets regardless of expression of CD14high or CD14+low, therefore highlighting the significance of further subdivision of monocytes into four subpopulations.
Conspiracy beliefs about the origin of HIV/AIDS in four racial/ethnic groups

We examined beliefs about the origin of HIV as a genocidal conspiracy in men and women of four racial/ethnic groups in a street intercept sample in Houston, Texas. Groups sampled were African American, Latino, non-Hispanic white, and Asian. Highest levels of conspiracy theories were found in women, and in African American and Latino populations (over a quarter of African Americans and over a fifth of Latinos) with slightly lower rates in whites (a fifth) and Asians (less than one in ten). Reductions in condom use associated with such beliefs were however only apparent in African American men. Conspiracy beliefs were an independent predictor of reported condom use along with race/ethnicity, gender, education, and age group. Data suggest that genocidal conspiracy beliefs are relatively widespread in several racial/ethnic groups and that an understanding of the sources of these beliefs is important to determine their possible impact on HIV prevention and treatment behaviors.
Electronic structure of disordered conjugated polymers: polythiophenes.

Electronic structure of disordered semiconducting conjugated polymers was studied. Atomic structure was found from a classical molecular dynamics simulation, and the charge patching method was used to calculate the electronic structure with the accuracy similar to the one of density functional theory in local density approximation. The total density of states, the local density of states at different points in the system, and the wave functions of several states around the gap were calculated in the case of poly(3-hexylthiophene) (P3HT) and polythiophene (PT) systems to gain insight into the origin of disorder in the system, the degree of carrier localization, and the role of chain interactions. The results indicated that disorder in the electronic structure of alkyl-substituted polythiophenes comes from disorder in the conformation of individual chains, while in the case of polythiophene there is an additional contribution due to disorder in the electronic coupling between the chains. Each of the first s...
Investigation of an internal PET probe for prostate imaging

Abstract We present a Monte Carlo simulation study of an application-specific positron emission tomography (PET) imaging device for the prostate that is capable of higher spatial resolution and sensitivity than a conventional PET scanner. The internal detector consists of an array of 1 mm×1 mm×3 mm LSO crystals coupled with avalanche photodiodes. The internal detector works in coincidence with a conventional external PET scanner to record two sets of coincidences: those occurring between the internal detector and the external ring, and conventional PET coincidences occurring between detectors of the external ring. Because of its proximity to the prostate, information from the internal detector supports both high resolution (∼1 mm FWHM) and efficiency while coincidence events recorded solely by the external detector provide complete tomographic data for image reconstruction.
Stego Scrubbing A New Direction for Image Steganography

We propose a new method for dealing with steganography. Instead of simply attempting to find the steganography, we propose an architecture that will remove the steganography, we call this stego scrubbing. This paper describes our philosophy and lays the ground work for the actual development of a stego scrubber, which can be inserted in a manner similar to a guard or firewall.
DEVELOPING AREMA ROAD PROFILE MODELS WITH A STATIONARY RESIDUAL PROCESS

Abstract The principal excitation to a vehicle's chassis system is the road profile. Simulating a vehicle traversing long roads is impractical and a method to produce short roads with given characteristics must be developed. An autoregressive model of non-stationary road profile data has been developed previously. This work examines the residual process of such an ARIMA model. Statistical techniques are developed and used to examine the distribution of the residual process and the preliminary results are demonstrated. Implications of this work to characterizing road profiles and future studies are discussed.
We've been so long at the fair: Two decades of psychology on display

Since 1975, Nebraska Wesleyan University has conducted a biennial psychology fair. Undergraduate psychology students pre-sent a wide variety of laboratory exhibits and displays for the benefit of high-school psychology students and their teachers, and distinguished visiting psychologists due lectures and meet with high school teachers. More than 15,WO high-school visitors have participated in the fair, which aims to provide public education, career information, resources and networking for high-school psychology teachers, and educational opportunity for undergraduates.
Electrocatalytically Active Graphene-Platinum Nanocomposites. Role of 2-D Carbon Support in PEM Fuel Cells

The use of a 2-D carbon nanostructure, graphene, as a support material for the dispersion of Pt nanoparticles provides new ways to develop advanced electrocatalyst materials for fuel cells. Platinum nanoparticles are deposited onto graphene sheets by means of borohydride reduction of H2PtCl6 in a graphene oxide (GO) suspension. The partially reduced GO-Pt catalyst is deposited as films onto glassy carbon and carbon Toray paper by drop cast or electrophoretic deposition methods. Nearly 80% enhancement in the electrochemically active surface area (ECSA) can be achieved by exposing partially reduced GO-Pt films with hydrazine followed by heat treatment (300 °C, 8 h). The electrocatalyst performance as evaluated from the hydrogen fuel cell demonstrates the role of graphene as an effective support material in the development of an electrocatalyst.
Determinants of trimetrexate lethality in human colon cancer cells

We examined the cytotoxicity and biochemical effects of the lipophilic antifol trimetrexate (TMQ) in two human colon carcinoma cell lines, SNU-C4 and NCI-H630, with different inherent sensitivity to TMQ. While a 24 h exposure to 0.1 microM TMQ inhibited cell growth by 50-60% in both cell lines, it did not reduce clonogenic survival. A 24 h exposure to 1 and 10 microM TMQ produced 42% and 50% lethality in C4 cells, but did not affect H630 cells. Dihydrofolate reductase (DHFR) and thymidylate synthase were quantitatively and qualitatively similar in both lines. During drug exposure, DHFR catalytic activity was inhibited by > or = 85% in both cell lines; in addition, the reduction in apparent free DHFR binding capacity (< or = 20% of control), depletion of dTTP, ATP and GTP pools and inhibition of [6-3H]deoxyuridine incorporation into DNA were similar in C4 and H630 cells. TMQ produced a more striking alteration of the pH step alkaline elution profile of newly synthesised DNA in C4 cells compared with 630 cells, however, indicating greater interference with DNA chain elongation or more extensive DNA damage. When TMQ was removed after a 24 h exposure to 0.1 microM, recovery of DHFR catalytic activity and apparent free DHFR binding sites was evident over the next 24-48 h in both cell lines. With 1 and 10 microM, however, persistent inhibition of DHFR was evident in C4 cells, whereas DHFR recovered in H630 cells. These data suggest that, although DHFR inhibition during TMQ exposure produced growth inhibition, DHFR catalytic activity 48 h after drug removal was a more accurate predictor of lethality in these two cell lines. Several factors appeared to influence the duration of DHFR inhibition after drug removal, including initial TMQ concentration, declining cytosolic TMQ levels after drug removal, the ability to acutely increase total DHFR content and the extent of TMQ-mediated DNA damage. The greater sensitivity of C4 cells to TMQ-associated lethality may be attributed to the greater extent of TMQ-mediated DNA damage and more prolonged duration of DHFR inhibition after drug exposure.
The taxonomic and ecological status of the environmentally restricted spongillid species of North America. IV. Spongilla heterosclerifera Smith 1918

The taxonomic status, present distribution and specific threats to the existence of the environmentally restricted freshwater sponge, Spongilla heterosclerifera Smith 1918 were investigated. This species, collected only from Oneida Lake, New York, has not colonized other habitats and continues to exhibit typical diagnostic characteristics, thus qualifying as a valid environmentally restricted species. Although the sponge presently colonizes two sites in the lake, both near the northwestern shore, the total absence of sponge fauna from other lake regions near more heavily populated areas of this species. Physicochemical data from Oneida Lake greatly extend the known environmental parameters of Spongilla heterosclerifera.