cssi/SciSciGPT-SciSciNet huggingface dataset:
Rapidly responsive adaptations in malignant astrocytomas under hypoxic conditions, as targets for novel brain tumor treatments, includes the PI3K/Akt/GSK-3 pathway

Proc Amer Assoc Cancer Res, Volume 45, 2004 3002 Objective: Malignant astrocytomas are deadly, treatment-resistant brain tumors. Our goal is to identify new treatment targets in malignant astrocytomas. Previous therapies, developed using normoxic conditions, have not worked well. Astrocytic potential for gluconeogenic removal of lactate may help to counteract metabolic stress during treatment. We propose that astrocytic metabolism requires brain tumor therapy to target cellular adaptations to hypoxia, as well as normoxic functions. Phosphorylations and dephosphorylations of key proteins, including phosphatidylinositol-3-kinase (PI3K)/Akt/glycogen synthase kinase-3 (GSK-3) pathway components, are proposed to trigger rapid, critical responses to hypoxia. Mutated phosphatase and tensin homolog, PTEN , commonly seen in malignant astrocytomas, allows anomalous activation of the PI3K/Akt/GSK-3 pathway, leading to activated glycogen synthase, thus providing additional removal of lactate as glycogen in poorly-perfused, invading tumor cells. Methods: Quantifying cellular adjustments to hypoxia, within 5 hrs of exposure, provided detection of the rapid adaptations that bypass the need for transcription factor-mediated alterations of protein levels. Quantifying 5 hr migration assays of U87 astrocytoma cells (mutated PTEN ) under hypoxic conditions, following restoration of PTEN- wild type (WT) with transient adenoviral transfections, revealed PTEN’s contribution to control of hypoxic cell migration via its negative regulation of the pathway. Peptide competition studies of GSK-3alpha’s phosphorylation by Akt indicated whether inhibitory drugs can be developed to shut down downstream signaling leading to glycogen synthesis in PTEN -mutated astrocytomas. Results: Previously, wortmannin (3.0 –30.0 nM), a specific PI3K inhibitor, suppressed hypoxic U87 migration with a dose response. Restoration of PTEN -WT in U87 cells, followed by functional assays showed significantly decreased, 50.4% (95% CI = 35.0 to 65.8%), migration in hypoxia compared to normoxia, when control vector hypoxic migration was maintained at levels comparable to normoxic migration (p=0.3, two-tailed, paired samples, 4 assays). Previously, whole cell and pseudopodal lysates showed that GSK-3alpha was phosphorylated at peak levels in the pseudopodal leading edge. Preliminary competition studies showed that a peptide containing an 11 residue sequence of the GSK-3alpha phosphorylation site inhibited phosphorylation by cell derived Akt with a dose response at 250 to 1000-fold greater amounts than substrate. Conclusion: Anomalous PI3K/Akt/GSK-3alpha pathway activity in PTEN -mutated astrocytoma cells offers novel targets for future drug therapies to suppress hypoxic migration required for invasion. We thank The Nick Eric Wichman Foundation for encouragement and financial support.
An allometry-based model of the survival strategies of hydraulic failure and carbon starvation

A simplified soil–plant–atmosphere–continuum model of carbon starvation and hydraulic failure is developed and tested against observations from a drought-manipulation experiment in a woodland dominated by pinon pine (Pinus edulis) and juniper (Juniperus monosperma) in New Mexico. The number of model parameters is reduced using allometric relationships. The model can represent more isohydric (pinon) and more anisohydric (juniper) responses. Analysis of the parameter space suggests four main controls on hydraulic failure and carbon starvation: xylem vulnerability curve, root:shoot area ratio, rooting depth and water use efficiency. For pinon, an intermediate optimal (1.5–2 m2 m−2) tree leaf area index reduces the risk of hydraulic failure. For both pinons and junipers, hydraulic failure was relatively insensitive to root:shoot ratio across a range of tree LAI. Higher root:shoot ratios however strongly decreased the time to carbon starvation. The hydraulic safety margin of pinons is strongly diminished by large diurnal variations in xylem/leaf water potential. Diurnal drops of water potential are mitigated by high maximum hydraulic conductivity, high root:shoot ratio and stomatal regulation (more isohydric). The safety margin of junipers is not very sensitive to diurnal drops in water potential so that there is little benefit in stomatal regulation (more anisohydric). Narrower tracheid diameter and a narrower distribution of tracheid diameters reduce the risk of hydraulic failure and carbon starvation by reducing diurnal xylem water potential drop. Simulated tree diameter-dependent mortality varies between these two species, with pinon mortality decreasing with increasing tree size, whereas juniper mortality increases with tree size. Juvenile pinons might thus be overimpacted by water stress. Copyright © 2015 John Wiley & Sons, Ltd.
Membrane‐initiated estradiol signaling increases tyrosine hydroxylase promoter activity with ERα in PC12 cells

Tyrosine hydroxylase (TH) promoter activity is induced by 17beta-estradiol (E(2)) in PC12 cells expressing estradiol receptor-alpha (ERalpha) requiring a cAMP/calcium response element (CRE/CaRE) at -45. To examine whether membrane-initiated estradiol signaling is underlying this induction, cells co-transfected with TH reporter construct and ERalpha expression vector were exposed to membrane-impermeant estradiol conjugate (beta-estradiol-6-(O-carboxy-methyl) oxime-bovine serum albumin, E(2)BSA). TH promoter activity was elevated by E(2)BSA in dose- and time-dependent manner. E(2)BSA also elicited rapid phosphorylation of CRE binding protein (CREB) and increased CRE-driven promoter activity. Over-expression of dominant negative forms of CREB, with mutations in DNA binding or phosphorylation site, prevented TH promoter response to E(2)BSA. Pre-treatment with protein kinase A (PKA) and MEK inhibitors reduced E(2) dependent phosphorylation of CREB and ERK, and also decreased induction of TH promoter activity by E(2) or E(2)BSA. Blocking S-palmitoylation of ERalpha with C451A mutation and/or pre-treatment with 2-Bromopalmitate did not prevent but instead enhanced E(2) or E(2)BSA-elicited induction of TH promoter activity. These findings reveal, for the first time, that estradiol induction of TH gene transcription with ERalpha in PC12 cells involves membrane-initiated estradiol signaling, rapid activation of dual PKA/MEK signaling pathways, leading to CREB phosphorylation, acting at CRE/CaRE. The data demonstrate possible mechanism whereby estradiol affects catecholaminergic systems in vivo.
Committed subcutaneous preadipocytes are reduced in human obesity.

Aims/hypothesis The aim of this study was to test whether the availability of committed preadipocytes in abdominal and femoral subcutaneous adipose tissue varies with obesity and body fat distribution. Methods Body composition, fat cell size, committed preadipocytes and macrophages were measured in subcutaneous abdominal and femoral adipose depots of 17 lean, 16 upper-body-obese (UBO) and 13 lower-body-obese (LBO) women. Preadipocytes and macrophages were identified by simultaneous staining with the respective markers aP2 and CD68. In a subset of samples we measured preadipocyte proliferation, differentiation and susceptibility to apoptosis. Results Abdominal adipocytes were smaller in lean than in obese women. Committed preadipocytes represented a greater fraction of stromovascular cells in lean than in obese women but were similar between UBO and LBO women (abdomen: ∼30±3 vs ∼17±2%; thigh: ∼30±3 vs ∼17±2%). Preliminary data suggested that preadipocyte kinetics were similar in LBO and lean women, whereas preadipocytes of UBO women differentiated less and were more susceptible to apoptotic stimuli. The fraction of stromovascular cells that were macrophages was greater in both depots in obese women (UBO and LBO) than in normal-weight women, but the difference was not statistically significant. Conclusions/interpretation The proportion of subcutaneous adipose tissue stromovascular cells that are committed preadipocytes is reduced with obesity. This could be due to greater recruitment of preadipocytes to adipogenesis or greater preadipocyte apoptosis, depending upon the obesity phenotype. These data are consistent with the concept that body fat distribution may be regulated partly through differences in adipogenesis.
Catalysis of hydrogen transfer in a tetralin-coal system

Hydrogen transfer from donor solvents to coal has been studied since the development of the Pott-Broche process [ 1--5]. Such hydrogen transfer occurs in the absence of external (added) catalysts. Possible catalysis of the hydrogen transfer by external catalysts has apparently received little attention. This communicat ion is concerned with hydrogen donation from tetralin to coal in the presence of either "cobalt-molybdate"-alumina (Co/Mo/AI203) or stannous chloride (SnC12" 2H20). The former is known to be outstanding for hydrodesulfurization, the latter for hydroliquefaction of coal. Procedures and calculational methods differed in detail from those described by Neavel [5], but definitions of hydrogen transfer and coal conversion are the same as his.
Combined effects of best management practices on water quality in oxbow lakes from agricultural watersheds

Abstract Water quality conditions in three oxbow lakes were examined before and after best management practices (BMPs) implementation within the Mississippi Delta. Experimental design called for the development of structural and cultural treatments to reduce sediment and associated pollutants entering watershed oxbow lakes. Three watersheds were selected and developed with different levels of BMPs. Changes in lake water quality were used as measures of management success. Analyses of water quality data prior to the implementation of BMPs suggested the lakes were stressed and ecologically damaged due to excessive sediment inflow. Significant improvements in water quality were observed with the use of cultural and structural BMPs. Sediments decreased 34–59%, while Secchi visibility and chlorophyll generally increased. The most dramatic improvements in water quality occurred in the two watersheds that featured cultural practices and combinations of cultural and structural practices. Reducing suspended sediment concentrations in these oxbow lakes favored phytoplankton production resulting in increased chlorophyll concentrations and higher concentrations of dissolved oxygen. Cultural BMPs, more so than structural BMPs, play a vital role in improving lake water quality, and are needed in addition to structural measures to ensure improved water quality in oxbow lakes receiving agricultural runoff.
Comparison of different methods of evaluation of weight functions for 2-D mixed-mode fracture analyses

Abstract In this paper, two different techniques for mixed-mode type engineering fracture analysis, by using the weight-function method, are presented. These two methods are (a) the virtual crack extension technique (VCE), and (b) the equivalent domain integral method (EDI). For mixed-mode weight-function evaluation, a technique of using two reference load states, both of which cannot be either pure mode I or pure mode II, is combined with the above mentioned numerical schemes. The numerical results show that the weight functions calculated by these two methods coincide with each other well. With the proposed techniques, it is very straightforward to perform fracture analysis of isotropic, orthotropic and composite materials.
Feasibility study of an air-coupled acoustic sensor for measuring ground vibrations

Representative data pertaining to various critical aspects of air-coupled ultrasonic Doppler sensing of ground vibrations are presented. The behavior of an ultrasonic sensor is systematically compared with that of commercial laser vibrometers. The inherent drawbacks and advantages of both techniques are discussed and evaluated in systematic experiments. The experiments are designed so as to synthesize various scenarios that may be encountered in practice. Thus the vibration sensing capability of ultrasonic vibrometers is investigated in cases including flat and grass-covered surfaces, granular media, with and without ambient air motion. The work is supported by the Office of Naval Research.
Food Safety, Labor Costs, and the Effects on Quick Service Restaurant Revenues

With the increasing need to maintain safe food practices in restaurants, this article explores the relationships between unit food safety performance, labor costs, and revenues in quick service restaurants. Namely, the goals of this study were to explore associations between food safety performance and restaurant revenues, labor costs and restaurant revenues as well as the relationship between labor costs and food safety performance. Using a theoretical foundation of organizational learning as support for lowering labor costs, research questions were answered using ANCOVAs, independent t-tests and Pearson correlations. Incorporating data from 1,190 quick service restaurant units, the study found relationships among the variables in that lower labor costs typically result in greater financial and food safety performance. Moreover, greater food safety performance also tended to result in greater financial performance. Theoretical and practical implications for the restaurant industry are discussed.
NUMERICAL SOLUTIONS TO ONE-DIMENSIONAL PROBLEMS OF THERMOELASTIC CONTACT

Abstract A numerical method, based on the Crank-Nicolson discretisation, is applied to one-dimensional thermoelastic contact problems. Such problems can be reduced, using an appropriate transformation, to the heat equation with a nonlinear and nonlocal source term. It is proved that the method converges. A number of numerical experiments are presented to illustrate the method and the behavior of the solutions to the problem.
Multiwavelength three-dimensional near-infrared tomography of the breast: initial simulation, phantom, and clinical results

Three-dimensional (3D), multiwavelength near-infrared tomography has the potential to provide new physiological information about biological tissue function and pathological transformation. Fast and reliable measurements of multiwavelength data from multiple planes over a region of interest, together with adequate model-based nonlinear image reconstruction, form the major components of successful estimation of internal optical properties of the region. These images can then be used to examine the concentration of chromophores such as hemoglobin, deoxyhemoglobin, water, and lipids that in turn can serve to identify and characterize abnormalities located deep within the domain. We introduce and discuss a 3D modeling method and image reconstruction algorithm that is currently in place. Reconstructed images of optical properties are presented from simulated data, measured phantoms, and clinical data acquired from a breast cancer patient. It is shown that, with a relatively fast 3D inversion algorithm, useful images of optical absorption and scatter can be calculated with good separation and localization in all cases. It is also shown that, by use of the calculated optical absorption over a range of wavelengths, the oxygen saturation distribution of a tissue under investigation can be deduced from oxygenated and deoxygenated hemoglobin maps. With this method the reconstructed tumor from the breast cancer patient was found to have a higher oxy-deoxy hemoglobin concentration and also a higher oxygen saturation level than the background, indicating a ductal carcinoma that corresponds well to histology findings.
ELECTRONIC PRESCRIBING: FRIEND OR FOE? AN AUDIT OF PRESCRIBING ERRORS AFTER THE INTRODUCTION OF AN ELECTRONIC PRESCRIBING SYSTEM IN NEONATES AND CHILDREN

Objective To compare the rate, nature and clinical significance of prescribing errors, before and after the introduction of electronic prescribing, in neonates and children. Methods The study was conducted at a large teaching hospital comprising, national tertiary and local paediatric services. Prescribing errors were prospectively identified over a two week period (excluding weekends) on six paediatric and one neonatal ward. The errors were then recorded and classified1 on ward visits and consultant led ward rounds. The clinical significance was measured using a validated, reliable method.2 Four health professionals, experienced in paediatrics scored each error on a scale of 1–10. A mean was then taken of the score and the value was used as an indication of the severity. Data were collated and analysed using Microsoft Excel. Data were collected in this way both during the pre-electronic (paper-based) prescribing period (January 2012) and the post-electronic prescribing period (March 2013). The results from each audit were then compared to ascertain the impact of the electronic prescribing system. Results A total of 2,264 medication orders were written during the study period (4 weeks total, 2 weeks before and 2 weeks after). Prescribing errors were identified in 275 prescriptions. Before the implementation of the electronic prescribing system there were 1117 medication orders of which 95 contained prescribing errors (8.5%). 18.6% of the errors were considered to be of minor clinical significance, 80.4% had a moderate outcome and 1% had a potentially severe outcome. After the introduction of the electronic prescribing system, there were 1147 medication orders of which 180 contained prescribing errors (15.7%). 26.6% of the errors were considered to have minor outcome and 73.4% were considered to have a moderate outcome. None of the prescribing errors intercepted during the post-EP period were considered to have a severe outcome. The ward area with the highest error rate was paediatric critical care (40%). Morphine was the drug associated with the highest number of errors. The most common type of error was continuation of a prescription for longer than necessary. A number of errors were eliminated completely by the introduction of electronic prescribing. Conclusions There was an increase in the prescribing error rate after the introduction of an electronic prescribing system however the nature of the errors had changed. The clinical significance of the errors remained approximately the same. A large multi-centre study is required to confidently assess the impact of electronic prescribing on the rate, nature and clinical significance of prescribing errors in neonates and children.
TELEVISION AND ITS AUDIENCES AS DIMENSIONS OF BEING: CRITICAL THEORY AND PHENOMENOLOGY *

John Fiske and John Hartley, in their Reading Television (1978), argue that the audience function of the television medium is formulated according to a "bardic" notion. The term "bardic" stresses the idea that television, as a primary mediator of Western culture, functions as social ritual, articulating and celebrating the central concerns of the society (culture) for whom its messages are intended. This perspective suggests that television can be understood best from a Communication Theory standpoint, that is, by concentrating equally on messages and their codes, communicators' intentions, and audiences' responses (Fiske and Hartley, 1978, p. 85). The purpose of my essay is three-fold. First, I briefly outline the position articulated by Fiske and Hartley (elaborating and clarifying their position in subsequent sections). Second, I examine it according to the critical theory paradigm of the Frankfurt School in order to determine whether and to what degree it "fits" within such a paradigm. Third, I explore how existential phenomenology might approach Fiske and Hartley's problematic, using as my criterion for analysis the phi? losophic position announced by Maurice Merleau-Ponty. Fiske and Hartley belong to the tradition of British "cultural studies," which defines culture as the whole complex process by which meanings and definitions are socially constructed and historically transformed. As "second force" critical theorists (Lanigan, 1981, p. 142), their theoretical aim is to understand how culture should be specified in itself and in relation to production and social relations (O'Sullivan et al. 1983, p. 61). At an empirical level, they engage textual analyses of those cultural practices and forms in order to illustrate how people can
The loomingness of danger: Does it discriminate focal phobia and general anxiety from depression?

In three studies, we examine the apparent loomingness, or rapid forward motion, that anxious individuals may perceive in danger. Results of the current studies show that individuals who are phobic of specific focal stimuli—spiders—may perceive loomingness in the dangers they typically fear but not in other dangers. Conversely, individuals who are generally anxious in mood perceive loomingness in dangers which are related to general anxiety but not in those related to spiders. Although the apparent loomingness of dangers is positively related to anxiety and specific phobic fears, it appears to be unrelated or negatively related to depression. Results of path analyses (Studies 1 and 2) and a study with an experimental methodology (Study 3) appear to be consistent with a proposed mediated sequence in which the perception of loomingness in danger helps to activate threat cognitions that lead to anxiety and fear.
(-) Arctigenin and (+) pinoresinol are antagonists of the human thyroid hormone receptor β.

Lignans are important biologically active dietary polyphenolic compounds. Consumption of foods that are rich in lignans is associated with positive health effects. Using modeling tools to probe the ligand-binding pockets of molecular receptors, we found that lignans have high docking affinity for the human thyroid hormone receptor β. Follow-up experimental results show that lignans (−) arctigenin and (+) pinoresinol are antagonists of the human thyroid hormone receptor β. The modeled complexes show key plausible interactions between the two ligands and important amino acid residues of the receptor.
Tracking ecology over geological time: evolution within guilds of vertebrates

Community structure, stability and change can be observed in the fossil record over timescales that far exceed what is possible in the present. Recent quantitative studies on ecological structure withion ancient guilds of various vertebrate predators, inlcuding birds, mammals and reptiles, have revealed a common pattern of iterative replacement of feeding ecomorphs over time, despite large differences in phylogenetic composition. As a result, patterns of resource division among sympatric carnivores remain stable over many millions of years and probably reflect interspecific competition and aspects of the food resource.
Old yellow enzyme at 2 A resolution: overall structure, ligand binding, and comparison with related flavoproteins.

Abstract Background: Old yellow enzyme (OYE) was the first flavoenzyme purified, but its function is still unknown. Nevertheless, the NADPH oxidase activity, the flavin mononucleotide environment and the ligand–binding properties of OYE have been extensively studied by biochemical and spectroscopic approaches. Full interpretation of these data requires structural information. Results The crystal structures of oxidized and reduced OYE at 2 A resolution reveal an α / β –barrel topology clearly related to trimethylamine dehydrogenase. Complexes of OYE with p –hydroxybenzaldehyde, β –estradiol, and an NADPH analog show all three binding at a common site, stacked on the flavin. The putative NADPH binding mode is novel as it involves primary recognition of the nicotinamide mononucleotide portion. Conclusion This work shows that the striking spectral changes seen upon phenol binding are due to close physical association of the flavin and phenolate. It also identifies the structural class of OYE and suggests that if NADPH is its true substrate, then OYE has adopted NADPH dependence during evolution.
Teaching visual aspects in an introductory computer graphics course

Abstract Computer science students contemplating a career in graphics need to develop a visual sense, but traditional course topics do not meet this need. Visual analysis is a teaching technique developed for computer science instructors that helps impart this ability. Requiring a minimal amount of classroom time, visual analysis imparts a broad knowledge of visual effects not covered in a traditional introductory course. Through the use of a few visual cues, students learn to visually identify surface algorithms, shaders and lighting techniques. An interactive software package called TERA (Tool for Exploring Rendering Algorithms) provides nearly a million image combinations that students can use to practice their visual identification skills. As a result, students gain a broader knowledge of graphics and become better program developers.
A comparison of the locomotor effects of 5-hydroxytryptamine and 5-hydroxytryptophan administered via two systemic routes

Abstract This study compared the effects of systemically administered 5-hydroxytryptamine (5-HT) and 5-hydroxytryptamine (5-HT) and 5-hydroxytryptophan (5-HTP) on tilt cage locomotor activity in rats. 5-HT was a more potent inhibitor of activity than 5-HTP via both the s.c. and i.p. routes. The effect of 5-HT itself was greater when administered i.p., whereas the effects of 5-HTP were independent of the route of administration. These results indicate that behavioral changesfollowing 5-HTP injection may be attributable to the peripheral effects of 5-HT.
Thermal modulation of cutaneous mucus discharge as a determinant of evaporative water loss in the frog, Rana catesbeiana

1. Cutaneous mucus glands of Rana catesbeiana discharge lumenal fluid onto the surface of the integument synchronously and periodically. Each discharge of fluid is a rapid and discrete event and can be viewed with magnification in the living animal. Discharge occurs in response to sympathetic nervous stimulation. 2. The frequency of mucus discharge depends upon central nervous impulses and increases over the approximate range of body temperature 20–28° C. Discharge frequencies during heating exceed steady state values at identical temperatures, and may be as high as 17/minute. Local heating of the thigh does not elicit changes in discharge frequency in that region, whereas local heating of the head does. Transections and lesions of the brain suggest that the anterior hypothalamus is involved in controlling mucus gland activity. Peripheral afferents appear to modify central impulses determining the frequency of mucus discharge. 3. Direct measurements of cutaneous evaporative water loss were made by recording humidity changes of air as it passed over an area of skin beneath a ventilated capsule. Frogs which frequently discharged mucus maintained steady states of evaporative water loss comparable to that of a free water surface. Frogs in which mucus gland activity was inhibited by sympathetic blockade demonstrated drying of the integument and declining rates of evaporative water loss. 4. It is suggested that thermal modulation of mucus discharge possibly functions to maintain a moist and viable integument during terrestrial basking.
Divided Saphenectomy for Varicose Vein in Ambulatory Surgery

We performed divided saphenectomy (DS) for varicose vein in ambulatory surgery with minimal incisions. Under tumescent local anesthesia, this procedure ligates all perforators in the thigh, preserving a route of venous drainage, and reduces bruising by ligating all tributaries. Also, DS does not need any special surgical instrument. Subcutaneous inguinal hemorrhage was observed in 4.9% (3/61), mild bruises were observed in 19.7% (12/61), and saphenous nerve neuralgia was 1.6% (1/61). Wound infection, deep venous thrombosis, and edema were not observed. DS is a minimally invasive, simple, and cost-effective procedure.
Effect of Temperature, Photoperiod and Pretreatment Growing Condition on Floral Induction in Springbearing Strawberry

Abstract ‘Chandler’ strawberry plants (Fragaria X ananassa Duch.) were greenhouse grown under natural lighting and then placed into growth chambers at two constant temperatures of 16 °C and 26 °C and two day lengths of 9 h (SD) and 9 h photoperiod (NI) which was night interrupted with 3 h of incandescent radiation at 30-45 μmol s ∼ 1m ∼ 2 PAR. Plants were given different numbers of inductive cycles in growth chambers and then moved to the greenhouse where flowering and growth were monitored. Flowering was completely inhibited at 26 °C, regardless of pretreatment growing conditions such as pot sizes and plant ages, photoperiod and inductive cycles. At 16 °C, SD promoted floral induction compared to NI under all inductive cycles except a 7-day induction. The minimum number of inductive cycles required at 16 °C for floral induction was dependent on photoperiod and prior greenhouse treatment. Flowering rate was also affected by greenhouse treatment, photoperiod and inductive cycles. Runner production was affe...
Adsorption of Ethylmethylamine Vapor by Activated Carbon Filters

The adsorption of high concentrations of ethylmethylamine (EMA) vapor from a humid air stream by an activated carbon bed has been studied. The adsorption behavior is quite different from the adsorption of trace quantities from an aqueous solution. The introduction of surface groups has no apparent direct effect on EMA adsorption. However, because these surface groups enhance water adsorption from the air stream and because adsorbed water hinders organic vapor adsorption, the modified carbons exhibit a lower apparent capacity and slower adsorption kinetics for EMA than the untreated ones. EMA is adsorbed from the vapor phase by a different mechanism than it is adsorbed from the liquid phase. The effect of humidity was evaluated and shown to influence the breakthrough time.
Responses of hepatic phosphoenolpyruvate carboxykinase activities from normal and diabetic rats to quinolinate inhibition and ferrous ion activation

Abstract 1. 1. Phosphoenolpyruvate carboxykinase (GTP:oxaloacetate carboxy-lyase (transphosphorylating), EC 4.1.1.32) from tryptophan-treated normal rats, when assayed immediately after preparation is not activated by Fe2+ but is inhibited 65% by 2.0 mM quinolinate whether or not Fe2+ is present. As time of storage increases, the enzyme's sensitivity to Fe2+ activation returns as does the ability of quinolinate to more effectively inhibit the Fe2+-activated enzyme. 2. 2. Phosphoenolpyruvate carboxykinase from NaCl- and tryptophan-treated diabetic rats is activated about 2-fold by 20 μM Fe2+. Quinolinate (2.0 mM) inhibits the Fe2+-activated enzyme 65% compared to 20% inhibition of the non-Fe2+-activated enzyme. In these respects, the enzyme from NaCl- and tryptophan-treated diabetic rats acts in vitro just like the enzyme from NaCl-treated normal rats and unlike the enzyme from tryptophan-treated normal rats. Thus, the inability of tryptophan and quinolinate to inhibit gluconeogenesis and to alter the assayable activity of Phosphoenolpyruvate carboxykinase from diabetic rats in vivo is inconsistent with quinolinate's ability to inhibit the enzyme in vitro. 3. 3. Quinolinate's inhibition of Phosphoenolpyruvate carboxykinase from NaCl, tryptopha-treated normal and diabetic rats is of a ‘mixed’ nature. 4. 4. Hepatic cytosolic phosphoenolpyruvate carboxykinases from fasted normal guinea pigs, pigeons, and rabbits are activated 2–3-fold by Fe2+ and inhibition by quinolinate in the presence of Fe2+ ranges from 65–75% compared to no inhibition without Fe2+. Mitochondrial carboxykinases from these three species are only activated 20–30% by Fe2+, although quinolinate, which is ineffective as an inhibitor in the absence of Fe2+, inhibits the enzymes 40–50% in the presence of Fe2+.
A new droplet collision algorithm

Abstract The droplet collision algorithm of O'Rourke is currently the standard approach to calculating collisions in Lagrangian spray simulations. This algorithm has a cost proportional to the square of the number of computational particles, or “parcels”. To more efficiently calculate droplet collisions, a technique applied to gas dynamics simulations is extended for use in sprays. For this technique to work efficiently, it must be able to handle the general case where the number of droplets in each parcel varies. The present work shows how the no-time-counter (NTC) method can be extended for the general case of varying numbers of droplets per parcel. The basis of this improvement is analytically derived. The new algorithm is compared to closed-form solutions and to the algorithm of O'Rourke. The NTC method is several orders of magnitude faster and slightly more accurate than O'Rourke's method for several test cases. The second part of the paper concerns implementation of the collision algorithm into a multidimensional code that also models the gas phase behavior and spray breakup. The collision computations are performed on a special collision mesh that is optimized for both sample size and spatial resolution. The mesh is different every time step to further suppress the artifacts that are common in the method of O'Rourke. The parcels are then sorted into cells, so that a list of all the parcels in a given cell are readily available. Next, each cell is individually checked to see if it is so dense that a direct collision calculation is cheaper than the NTC method. The cheaper method is applied to that cell. The final result is a method of calculating spray droplet collisions that is both faster and more accurate than the current standard method of O'Rourke.
pH oscillations in transport processt

Abstract Oscillations in pH have been observed when a substrate passes through a synthetic membrane containing enzymes which possess the autocatalytic character in pH. In this paper, we present a mathematical model and computations to show the role of buffer on the oscillation. The theory shows that the oscillation strongly depends on the buffer concentration, in agreement with the experimental observation. In addition, we have found that depending on the nature of a buffer, a buffer can either enhance or suppress the oscillation. We have also shown that in the absence of buffer, oscillations in the papain-BAEE system which corresponds to those observed by Naparstek et al. arise only if the diffusion constant of OH − is at least 25 times larger than that measured by the experiment. An explanation for this discrepancy is given in this paper.
Food for Thought: Nourishing the Publication of Qualitative Research

In recent years, journal editors have issued loud and earnest calls for high-quality manuscripts based on qualitative methods. Yet, in reviewing the past several years of gerontological journals, including the Journal of Applied Gerontology (JAG), the authors noticed that the rate at which qualitative papers are published has held steady at modest percentages of the total number of published works. This essay explores this seemingly contradictory situation by providing insights into several key questions: Why are not more research articles published that use qualitative methods? Why is it important that qualitative researchers publish their works in applied venues like the JAG? What should authors of qualitative pieces keep in mind when developing their manuscripts?
Multiple levels of magma storage during the 1980 summer eruptions of Mount St. Helens, WA

Transitions in eruptive style—explosive to effusive, sustained to pulsatory—are a common aspect of volcanic activity and present a major challenge to volcano monitoring efforts. A classic example of such transitions is provided by the activity of Mount St. Helens, WA, during 1980, where a climactic Plinian event on May 18 was followed by subplinian and vulcanian eruptions that became increasing pulsatory with time throughout the summer, finally progressing to episodic growth of a lava dome. Here we use variations in the textures, glass compositions and volatile contents of melt inclusions preserved in pyroclasts produced by the summer 1980 eruptions to determine conditions of magma ascent and storage that may have led to observed changes in eruptive activity. Five different pyroclast types identified in pyroclastic flow and fall deposits produced by eruptions in June 12, July 22 and August 7, 1980, provide evidence for multiple levels of magma storage prior to each event. Highly vesicular clasts have H2O-rich (4.5–5.5 wt%) melt inclusions and lack groundmass microlites or hornblende reaction rims, characteristics that require magma storage at P≥160 MPa until shortly prior to eruption. All other clast types have groundmass microlites; PH20 estimated from both H2O-bearing melt inclusions and textural constraints provided by decompression experiments suggest pre-eruptive storage pressures of ∼75, 40, and 10 MPa. The distribution of pyroclast types within and between eruptive deposits can be used to place important constraints on eruption mechanisms. Fall and flow deposits from June 12, 1980, lack highly vesicular, microlite-free pyroclasts. This eruption was also preceded by a shallow intrusion on June 3, as evidenced by a seismic crisis and enhanced SO2 emissions. Our constraints suggest that magma intruded to a depth of ≤4 km beneath the crater floor fed the June eruption. In contrast, eruptions of July and August, although shorter in duration and smaller in volume, erupted deep volatile-rich magma. If modeled as a simple cylinder, these data require a step-wise decrease in effective conduit diameter from 40–50 m in May and June to 8–12 m in July and August. The abundance of vesicular (intermediate to deep) clast types in July and August further suggests that this change was effected by narrowing the shallower part of the conduit, perhaps in response to solidification of intruded magma remaining in the shallow system after the June eruption. Eruptions from July to October were distinctly pulsatory, transitioning between subplinian and vulcanian in character. As originally suggested by Scandone and Malone (1985), a growing mismatch between the rate of magma ascent and magma disruption explains the increasingly pulsatory nature of the eruptions through time. Recent fragmentation experiments Spieler et al. (2004) suggest this mismatch may have been aided by the multiple levels at which magma was stored (and degassed) prior to these events.
Thermally Responsive Swelling Properties of Polyacrylamide/Poly(acrylic acid) Interpenetrating Polymer Network Nanoparticles

Interpenetrating polymer network (IPN), random copolymer, and homopolymer nanoparticles of acrylamide and acrylic acid were prepared using an inverse emulsion polymerization technique. Differential scanning calorimetry and Fourier-transform infrared spectroscopy were used to examine the molecular structure of the prepared polymeric nanoparticles. The spherical morphology and size (∼250 nm diameter) of the nanoparticles was confirmed using scanning electron microscopy. Dynamic light scattering was used to determine the monodispersity of the particle size distribution and examine the thermally responsive swelling properties of the polymeric nanoparticle structures. Of the particle systems studied, only the IPN nanoparticles exhibited a unique, rapid sigmoidal swelling transition with temperature. These systems also achieved a much larger relative swelling volume compared to random copolymer and homopolymer particles comprised of acrylamide and acrylic acid. Increased cross-linker density resulted in an over...
Semilocal approach to nonlocal equations

Abstract One can classify nonlocal equations according to the value of a parameter, defined as the ratio between the range of nonlocality and the characteristic length of the diagonal part of the integral kernel. When this ratio is small, one can derive a local (differential) equation, which approximately reproduces the solutions of the nonlocal equation. Then using the methods already existing for the analysis of differential equations one can, with a relatively small effort, describe the properties of the solutions of nonlocal equations. It is not possible to attach to every nonlocal Schrodinger equation an equivalent local one (i.e. a differential equation of second order). The reason is that the spectrum of nonlocal equations is much richer and cannot be reproduced with a second order differential equation. When this is the case, the behaviour of the solutions of nonlocal equations is similar to that corresponding to nonlinear equations. The method presented here provides one not only with a quite simple approach for studying the properties of nonlocal equations, but also with a fairly accurate method of approximate solution, when the above-mentioned parameter is reasonably small.
Monitoring of diffusion processes with PDE models in wireless sensor networks

The monitoring of a diffuse process, such as the propagation of a toxic gas in an area, using the partial differential equation (PED) model via autonomous wireless sensor networks is studied in this research. Sensor nodes update the base station with their estimates of PDE model parameters rather than raw sensor measurements. Then, the base station can reconstruct the phenomenon through model parameters and initial and boundary conditions. In-network processing techniques to estimate the PDE coefficients are presented. A scheme is presented to provide a hybrid combination of decision and data fusion to find a proper tradeoff between estimate accuracy and energy efficiency. Besides, several open issues in this research context, such as identifiability of parameters, monitoring of time varying boundary conditions and unknown sources, are discussed.
Termination of Pacemaker-Mediated Tachycardia by Adenosine

A 30-year-old woman was referred for follow-up right- and left-heart catheterization 4 years after cardiac transplantation. She had an implanted epicardial pacemaker for bradycardia; this was programmed to the DDD mode. At the time of her catheterization, as a pigtail catheter was pulled back across the aortic valve, runs of premature ventricular complexes occurred and tachycardia with ventricular pacing spikes and ventricular capture was initiated at a rate of 126 beats/min. Adenosine 6 mg was given intravenously through a femoral venous sheath and within 20 s the tachycardia broke. The tachycardia was consistent with pacemaker-mediated tachycardia (PMT), a circus movement tachycardia occurring when ventricular pacing causes retrograde atrial depolarization followed by triggering of ventricular pacing. With reprogramming of the pacemaker to an AV delay of 160 ms and a postventricular atrial refractory period of 300 ms, no further episodes of PMT have occurred. This case illustrates that intravenous adenosine can effectively terminate PMT by causing ventriculoatrial block, thus interrupting the reentrant circuit by eliminating retrograde atrial activation.
Infectious Ethics: How Upright Employees Can Ease Concerns of Tacit Collusion

The recent spate of corporate scandals in the United States has led to a newfound emphasis on developing a culture of ethics within organizations. Many hope the leadership of a few can help persuade ethical behavior by others. This article suggests that direct interpersonal influences need not necessarily be present for individuals to spur such a culture. In this article, incentive contracts make use of relative performance evaluation, which gives rise to concerns of tacit collusion among employees. Ethical employees stand to alter the behavior of others, since their mere presence limits the number and size of potential collusive coalitions. As a result, the firm finds it much easier to motivate not only those who themselves are ethical but also those who act entirely in self-interest. (JEL J33, M14, M52)
Concomitant elective resection of pheochromocytoma and repair of aortic abdominal aneurysm

Perioperative management of a patient with ischemic heart disease with coexisting abdominal aortic aneurysm and pheochromocytoma creates a difficult management dilemma, and surgical intervention in these patients carries a significant risk. The state of catecholamine excess and various other coexisting factors can lead to simultaneous occurrence of abdominal aortic aneurysm and pheocromocytoma. The purpose of this report is to present an integrated approach to the management of concomitant abdominal aortic aneurysm and pheochromocytoma, where a combined surgical approach in addressing these two lesions was preferable due to patient comorbidities and surgical implications without significant complication.
Bombardment-produced disorder and SiH bonds in crystalline and amorphous silicon

Hydrogenation of silicon has been investigated under conditions in which lattice disorder and hydrogen concentration are independently controlled. Control of hydrogen concentration and disorder to produce a crystalline-to-amorphous transition was achieved by hydrogen ion implantation and self-ion bombardment, respectively. Hydrogen concentrations and depth distributions were determined by ion-beam-analysis techniques, and infrared absorption was used to measure the SiH stretch modes for chemically bound hydrogen. Hydrogen implanted into crystalline silicon is chemically trapped at the end of its range and introduces numerous Si---H stretch frequencies associated with crystalline defects. Subsequent amorphization by self-ion bombardment causes a coalescence of the SiH stretch modes to a 1985 ${\mathrm{cm}}^{\ensuremath{-}1}$ band which is characteristic of monohydride centers in amorphous silicon. We also find that the presence of hydrogen in silicon stabilizes disorder and reduces the silicon-ion fluence necessary to produce amorphization. Monohydride centers dominate in hydrogenated bombardment-amorphized silicon, but there is evidence for saturation of the monohydride center for concentrations greater than a few percent. Ion bombardment of sputter-deposited amorphous silicon with 3 at.% hydrogen causes a thermally stable transfer of hydrogen from dihydride to monohydride centers. The predominance of monohydride centers and saturation of such centers in silicon amorphized by ion bombardment is consistent with predictions of Phillips's model.