cssi/SciSciGPT-SciSciNet huggingface dataset:
Oncogenic and Wild-type Ras Play Divergent Roles in the Regulation of Mitogen-Activated Protein Kinase Signaling

H-Ras, K-Ras, and N-Ras regulate cellular growth and survival and are often activated by somatic mutation in human tumors. Although oncogenic lesions occur in a single Ras isoform within individual tumors, it is unclear whether the remaining wild-type isoforms play supporting roles in tumor growth. Here, we show that oncogenic and wild-type Ras isoforms play independent and nonredundant roles within the cell. Oncogenic Ras regulates basal effector pathway signaling, whereas wild-type Ras mediates signaling downstream of activated receptor tyrosine kinases (RTK). We show that both are necessary for exponential growth of Ras-mutant cell lines. Furthermore, we show that oncogenic Ras desensitizes signaling from EGF receptor (EGFR). Depletion of oncogenic Ras with siRNA oligonucleotides relieves this negative feedback, leading to the hyperactivation of EGFR and wild-type Ras signaling. Consistent with this model, combining oncogenic Ras depletion with EGFR inhibition potently increases cell death. Significance: The results of this study highlight a novel role for wild-type Ras signaling in cancer cells harboring oncogenic RAS mutations. Furthermore, these findings reveal that therapeutically targeting oncogenic Ras signaling alone may be ineffective owing to feedback activation of RTKs, and suggest that blocking upstream RTKs in combination with downstream effector pathways may be beneficial in the treatment of Ras-mutant tumors. Cancer Discov; 3(1); 112–23. ©2012 AACR . See related commentary by Hayes and Der, [p. 24][1] This article is highlighted in the In This Issue feature, [p. 1][2] [1]: /lookup/volpage/3/24?iss=1 [2]: /lookup/volpage/3/1?iss=1
New alleles of mgm1: a gene encoding a protein with a GTP-binding domain related to dynamin.

Three previously described genes that affect baker's yeast (Saccharomyces cerevisiae) mitochondrial DNA (mtDNA) or mitochondrial RNA, tpm2-1, mnal-1, and mgml-1, are shown to be alleles of the same gene. This report demonstrates that tpm2-1 does not affect recombination of mtDNA. Therefore, there is no evidence that this dynamin-like protein is involved in movement of mtDNA within a cell.
Modeling Conditional Yield Densities

Given the increasing interest in agricultural risk, many have sought improved methods to characterize conditional crop-yield densities. While most have postulated the Beta as a flexible alternative to the Normal, others have chosen nonparametric methods. Unfortunately, yield data tends not to be sufficiently abundant to invalidate many reasonable parametric models. This is problematic because conclusions from economic analyses, which require estimated conditional yield densities, tend not to be invariant to the modeling assumption. We propose a semiparametric estimator that, because of its theoretical properties and our simulation results, enables one to empirically proceed with a higher degree of confidence. Copyright 2003, Oxford University Press.
Infinite-randomness critical point in the two-dimensional disordered contact process.

We study the nonequilibrium phase transition in the two-dimensional contact process on a randomly diluted lattice by means of large-scale Monte Carlo simulations for times up to ${10}^{10}$ and system sizes up to $8000\ifmmode\times\else\texttimes\fi{}8000$ sites. Our data provide strong evidence for the transition being controlled by an exotic infinite-randomness critical point with activated (exponential) dynamical scaling. We calculate the critical exponents of the transition and find them to be universal, i.e., independent of disorder strength. The Griffiths region between the clean and the dirty critical points exhibits power-law dynamical scaling with continuously varying exponents. We discuss the generality of our findings and relate them to a broader theory of rare region effects at phase transitions with quenched disorder. Our results are of importance beyond absorbing state transitions because, according to a strong-disorder renormalization group analysis, our transition belongs to the universality class of the two-dimensional random transverse-field Ising model.
VISUAL EFFICIENCY — a microcomputer program for the analysis of action spectra

A microcomputer program for the analysis of complex action spectra is described. This program can take data gathered in a series of spectral ranges and fit them to a model consisting of multiple pigments, varying pigment concentrations, and absorption before the photosensitive pigment. Chi square and correlation analysis are performed on the final fit.
Cyanide-induced cytotoxicity to isolated hepatocytes.

Abstract The responses of various cell functional parameters to potassium cyanide (KCN) were investigated in isolated rat hepatocytes to examine their quantitative and temporal relationship to inhibition of mitochondrial respiration. Both cultures and suspensions of hepatocytes, maintained in hormone-supplemented culture medium at 37°C under an air: CO2 (95:5) atmosphere, were used in these studies. The earliest and most sensitive change detected was inhibition of O2 consumption ( EC 50 = 78 μ m ); other early changes included depression in ATP and ATP/ADP, inhibition of urea synthesis, and elevation in lactate/pyruvate. The effect on ATP depression at 10 min was reversed by replacement with fresh medium containing no cyanide ( t 1 2 =9 min ). Increased release of lactate dehydrogenase and acid phosphatase occurred much later during the incubation (120 or 240 min) and at much higher KCN concentrations (≥0.5 m m ) than the other changes. These observations are consistent with inhibition of mitochondrial respiration being the initiating or major contributing factor in cyanide-induced cytotoxicity in hepatocytes, but because of the difference in EC50 values for depression of O2 consumption and energy-dependent parameters and for intracellular enzyme release, other mechanisms may also contribute to cell death. Reduced glutathione content and lipid peroxidation in the cells, assessed by measuring thiobarbituric acid reactants, were not significantly changed, and the mechanism leading up to cell death remains uncharacterized. The cyanide concentrations in vitro that produced inhibition of O2 consumption were in the same range as those in blood and liver that inhibited cytochrome oxidase in vivo at lethality. The results in the hepatocyte model, therefore, can explain why the liver is not a target organ in massive, acute cyanide poisoning, in that overt signs develop at higher concentrations and after longer times than are applicable for the death of the animal.
Note on the Occurrence of Siphlonurus autumnalis (Ephemeroptera: Siphlonuridae) in a Montana Spring Brook

The little-known mayfly Siphlonurus autumnalis McDunnough (Ephemeroptera: Siphlonuridae) was col- lected from several locations in its floodplain habitats along the Middle Fork of the Flathead River in western Montana. To confirm identification, nymphs were reared along with an associated species, S. occidentalis Eaton (Ephemeroptera: Siphlonuridae). Adults emerged from 6 September until 16 October. Habitats are described and the first photos of the 2 sexes are provided.
Correlation functions and factorial correlator data.

The close connection between factorial moments and factorial correlators as integrals of the same underlying correlation function is explored, leading to extensions of sum rules previously suggested. Cumulants, which were previously found to be the fundamental building blocks for moments, have been analogously defined for the correlators also, revealing the true {ital n}-particle correlations. Decomposing the factorial correlators into cumulants, we find that the largest part of the correlators consists of two-particle correlations for NA22 data. The nonstationarity of the correlation function is found to affect the results to a surprisingly small degree. It is pointed out that all linking schemes for higher-order correlations must be tested not on the correlators but on the cumulants in order to claim success. Finally, applying our scheme to UA1 factorial moment data, we predict the size and shape of UA1 correlators.
Stability of Acid‐Resistant Red Porcelain Enamels

The comparative acid resistance of a series of enamels was determined by the loss-in-weight test and by the spot test. The stability of the red color oxide in these enamels was also studied by varying the alumina, fluoride, soda, and potassia contents in the frit. Improved acid resistance was obtained with no alumina and no fluoride in the frit. The stability of the red color was markedly influenced by the fluoride content; the absence of fluoride in the frit gave very poor stability.
Structural Modifications of Rigid-Rod Polymers

Research in our laboratory on lyotropic liquid crystalline polymers has provided a series of high modulus, high tenacity materials derived from benzobisazole rigid-rod polymers. A number of different structural modifications on these systems have been carried out in our laboratory. This paper will be focused on those structural variations made by maintaining the para-ordered geometry while modifying the structure with pendent groups.
Resident and "inflammatory" dendritic cells in human skin.

Dendritic cells (DCs) are a heterogeneous group of antigen-presenting leukocytes that are important in activation of both the innate and adaptive arms of the immune system. Although there are several different DC populations in the body, DCs are globally defined by their capacity for potent antigen presentation and naive T-cell activation. In noninflamed human skin during steady state, there are three main cutaneous DC populations: epidermal Langerhans cells, dermal myeloid DCs, and dermal plasmacytoid DCs. In psoriasis, a model for cutaneous inflammation, there is an additional population of myeloid dermal DCs—“inflammatory DCs”—which appears to be critical for disease pathogenesis.
Petrology and geochemistry of the Huerto Andesite, San Juan volcanic field, Colorado

The Huerto Andesite is the largest of several andesite sequences interlayered with the large-volume ash-flow tuffs of the San Juan volcanic field, Colorado. Stratigraphically this andesite is between the region's largest tuff (the 27.8 Ma, 3,000 km3 Fish Canyon Tuff) and the evolved product of the Fish Canyon Tuff (the 27.4 Ma, 1,000 km3 Carpenter Ridge Tuff), and eruption was from vents located approximately 20–30 km southwest and southeast of calderas associated with these ashflow tuffs. Olivine phenocrysts are present in the more mafic, SiO2-poor samples of andesite, hence the parent magma was most likely a mantle-derived basaltic magma. The bulk compositions of the olivine-bearing andesites compared to those containing orthopyroxene phenocrysts suggest the phenocryst assemblage equilibrated at 2–5 kbar. Two-pyroxene geothermometry yields equilibrium temperatures consistent with near-peritectic magmas at 2–5 kbar. Fractionation of phenocryst phases (olivine or orthopyroxene + clinopyroxene + plagioclase + Ti-magnetite + apatite) can explain most major and trace element variations of the andesites, although assimilation of some crustal material may explain abundances of some highly incompatible trace elements (Rb, Ba, Nb, Ta, Zr, Hf) in the most evolved lavas. Despite the great distance of the San Juan volcanic field from the inferred Oligocene destructive margin, the Huerto Andesite is similar to typical plate-margin andesites: both have relatively low abundances of Nb and Ta and similar values for trace-element ratios such as La/Yb and La/Nb.
The response of Galileo aft cover components to laser radiation

The aft region of the Galileo probe will be subjected to severe heat transfer rates dominated by the radiation contributions. To assess the response of several vehicle aft region components to thermal radiation, tests employing a 10 KW CO2 laser were conducted. The experiments evaluated the annulus/aft cover interface, the umbilical feedthrough assembly and the mortar cover seal assembly. Experimental evidence of the response of the phenolic nylon heatshield and quantitative measures of its effect on gap geometries of several vehicle components were acquired. In addition, qualitative measures of the survivability of the irradiated components were obtained.
Effect of ozone on gross photosynthesis of lichens

Abstract The lichens Pseudoparmelia caperata and Ramalina menziesii were subjected to short- and long-term fumigations. Pseudoparmelia caperata was fumigated with 200, 490, and 980 μg/m 3 of ozone for 12 hr. A significant decline in the rate of 14 CO 2 assimilation was seen at all concentrations. Ramalina menziesii was exposed to 200, 490, 980, and 1567 μg/m 3 of ozone for 12 hr, with no significant reduction in the rate of photosynthesis. Both species were also fumigated with 200 μg/m 3 of ozone for 6 hr on 5 consecutive days. Again, P. caperata results demonstrated a significant reduction of photosynthesis while R. menziesii did not. Field analyses indicated that P. caperata is undergoing stress in the Santa Monica Mountains of southern California, a region where ozone has been recorded at 200 μg/m 3 between 50 and 100 days per year. From results of these laboratory studies, it is inferred that ozone is contributing to the unusually low lichen cover observed in the field. However, the absence of R. menziesii from these mountains appears to be independent of ozone pollution.
Infant behaviors directed toward peers and adults in the presence and absence of mother

Social behaviors of 10- to 14-month-old infants were observed over the course of a semester while the infants played in a university parents' cooperative nursery. The group was comprised of 12 infants and their mothers. Proximal and distal, positive and negative social behaviors of these infants were recorded as they were directed toward their peers, their mothers, or other infants' mothers. Since the mothers were sometimes in and sometimes out of the room, comparisons could be made between social behaviors occurring in mother's absence and in her presence. The infants were more “social” and less “negative” toward their peers when mother was out of the room, and they exhibited more social behaviors toward their peers by the end of the semester. These results suggest that peer contacts may be facilitated by the absence of mothers and by continuing exposure to the same peers.
A cluster of cases of factitious Cushing's syndrome.

Objective: To review the patient profiles, laboratory data, and diagnostic approaches in factitious administration of glucocorticoids. Methods: Four cases of surreptitious use of glucocorticoids are presented. Clinical and laboratory data as well as imaging studies are summarized. Pertinent case reports in the literature are reviewed. Results: We report four cases of surreptitious use of glucocorticoids encountered within a 2-year period. All four patients were women without significant psychiatric histories. In three patients, the question of factitious Cushing's syndrome was suspected because of physical evidence or symptoms of Cushing's syndrome (or both) in the setting of suppressed cortisol levels. The fourth patient had undetectable cortisol levels in both serum and 24-hour urine samples but did not have signs or symptoms of adrenal insufficiency. In three cases, the diagnosis was confirmed by direct measurement of synthetic glucocorticoids in the patient's urine or serum. The fourth case was diagno...
Basicity of Some Phosphines in THF

[reaction: see text] The reaction of several phosphines with an acidic indicator gives both ion pairs and free ions. The value obtained for the pKa of tribenzylphosphine is shown to be reasonable by MO computations. An important limitation is demonstrated for the Fuoss equation of dissociation of ion pairs.
Community college transfer students’ probabilities of baccalaureate receipt as a function of their prevalence in four‐year colleges and departments

The present paper determines whether community college transfer students have higher baccalaureate rates when they enroll in four‐year colleges and departments that have larger shares of transfer students. Transfers attending non‐technical campuses with larger shares of transfers have higher eight‐year baccalaureate rates, but within‐campus increases in share transfers do not increase transfer graduation rates. Transfers in departments with large shares of transfer students have significantly lower graduation rates, but natives in such departments do not. Within‐department increases in transfer student presence are positively correlated with transfer eight‐year graduation rates and negatively correlated with native eight‐year graduation rates, indicating an opportunity for efficiency gains if influxes of transfers are separated from natives.
On weakly mixing homeomorphisms of the two-torus that are uniformly rigid

Abstract In this paper we explore some properties of weakly mixing homeomorphisms of the two-torus that are uniformly rigid. Specifically we will show that there is a large family of weakly mixing, uniformly rigid, strictly ergodic homeomorphisms of the two-torus. Also, we will show that if a sequence of natural numbers satisfies a certain growth rate, then we can construct a weakly mixing homeomorphism of the two-torus that is uniformly rigid with respect to that sequence.
Foam Mechanics at the Bubble Scale

By focusing on entire bubbles rather than films or vertices, a simple model is proposed for the deformation and flow of foam in which dimensionality, polydispersity, and liquid content can easily be varied. Simulation results are presented for the linear elastic properties as a function of bubble volume fraction, showing a melting transition where the static shear modulus vanishes and the relaxation time scale peaks. Results are also presented for shear stress versus strain rate, showing intermittent flow via avalanchelike topological rearrangements and Bingham-plastic behavior.
The Surgeon's Art

y subject is the art of surgery, its history and progression into the present hightech age. I have included artists' images from the collection of JAMA covers that I hope will combine with my words to bring some inspiration. A new century in American surgery is under way. It is fast moving, even frantic, with new science and technology appearing every day. In this stressful milieu, let us pause to view Michelangelo's Creation of Adam from the ceiling of the Sistine Chapel (Figure 1). I propose that we might also pause to reflect on the art of surgery. Practicing surgery in our current world-engaging in humane dialogue and making clinical judgments amid challenging medical, ethical, and economic forces at the interface of patient and surgeon-is a complex undertaking. It is a challenge that our forebears in surgery could not have foreseen. Furthermore, they could not have predicted the wave of disenchantment expressed by physicians and patients at the very time when the surgical armamentarium has become larger and finer and the achievements more spectacular than ever. In the literature of our field, the following question is posed: "Must there be an inverse relationship between technical outcome and service experience?" 1 No. However, Leon Eisenberg states, " [P] ublic dissatisfaction with care received has been increasing in recent years despite the greater and greater proficiency of medical and surgical specialists in reducing morbidity and mortality" .
Methylation of the glial fibrillary acidic protein gene shows novel biphasic changes during brain development

The gene for glial fibrillary acidic protein (GFAP) was analyzed in the rat for developmental changes in methylation of cytosine at CpG sequences as a correlate of the onset of GFAP mRNA expression and for the effect of methylation on GFAP promoter activity. The methylation of nine CpG sites in the GFAP promoter and ten sites in exon 1 was analyzed in F344 rats by a quantitative application of ligation-mediated polymerase chain reaction. Whole rat brain poly(A)+ RNA showed an exponential increase of GFAP mRNA after embryo day 14 that reached stable adult levels by postnatal day 10. During development, only the seven CpG sites in the far-upstream promoter showed large changes in methylation; these sites constitute the brain-specific domain of methylation described in adult rats (Teter et al: J Neurosci Res 39:680, 1994). These seven CpG sites showed a cycle of demethylation during the onset of GFAP transcription in the embryo (between embryonic day 14 and postnatal day 10) followed by remethylation at later postnatal ages when GFAP mRNA remains prevalent. The minimum levels of methylation across these CpG sites displayed a gradient with the lowest minima at the 3' sites. This demethylation/remethylation cycle is a novel phenomenon in DNA methylation during perinatal development. The demethylation/remethylation cycle during development was also shown by the opposite-strand cytosines. Two cytosines in this region that are conserved in rat and mouse also undergo the same demethylation/remethylation cycle in the mouse GFAP gene during development, implying evolutionary conservation and functional significance. As a further test of functional significance, a Luciferase reporter gene assay was evaluated in primary cultured astrocytes; the activity of the GFAP promoter was reduced when it was methylated at one or all CpG sites. Therefore, the GFAP promoter may be activated in rodent development by transient demethylation of a conserved brain-specific methylation domain.
Cyclic alternating pattern and positive airway pressure titration

Abstract Objective : To demonstrate that stability of the upper airway during continuous positive airway pressure (CPAP) titration is influenced by the microstructure of sleep as defined by the cyclic alternating pattern (CAP). Methods : Retrospective review of 12 CPAP titration records. The patterns of flow-limitation during CPAP at subtherapeutic pressures were characterized as ‘stable' (persistent and non-progressive inspiratory flow limitation) or ‘unstable' (progressive increase in inspiratory flow-limitation terminating in an arousal), and continuous periods of at least 10 min were identified. Sleep stage scoring by both conventional Rechtshaffen and Kales criteria and the CAP were done. The relationship between flow type and CAP was determined. Responses to an increase in applied pressure on flow-limitation were noted. Results : There were a total of 50 periods fulfilling the above criteria, totaling 1113 min of titration time. Thirty periods (757 min, 68% of total) showed a stable flow-limitation pattern. A total of 29/30 periods showing a stable flow pattern during sleep was scored as non-CAP, and only a single 18-min period of stable flow was scored as CAP. A total of 19/20 periods showing an unstable flow pattern was in sleep with CAP characteristics, the exception being a single 14-min period where unstable flow was noted in non-CAP. Flow-limitation was stable and non-progressive or absent during non-CAP, even at less than optimal pressures. This was noted irrespective of the presence or absence of delta sleep as scored by conventional criteria. Pressure increases during non-CAP, when the profile of the inspiratory flow was flattened, never resulted in a discernable change in the flow profile, while at least two-thirds of pressure increments during CAP periods improved flow. Conclusions : The microstructure of sleep as determined by CAP and non-CAP have practical implications for manual pressure titration algorithms and research on upper airway physiology during sleep. The appearance of a period of non-CAP, irrespective of conventionally scored delta sleep, may falsely suggest that the CPAP is optimal or close to it. Large increases in non-CAP that may be seen during a titration night can reduce the window of opportunity for titration. Increases in CPAP should be avoided in non-CAP.
Airway inflammation and central respiratory control: results from in vivo and in vitro neonatal rat.

Abstract In infants, respiratory infection elicits tachypnea. To begin to evaluate the role of brainstem cytokine expression in modulation of breathing pattern changes, we compared the pattern generated after endotracheal instillation of lipopolysaccharide (LPS) in in vivo rat pups to local pro-inflammatory cytokine injection in the nucleus tractus solitarius (nTS) in an in vitro en bloc brainstem spinal cord preparation. We hypothesized that both challenges would elicit similar changes in patterning of respiration. In anesthetized, spontaneously breathing rat pups, lipopolysaccharide (LPS) or saline was instilled in the airway of urethane-anesthetized rats (postnatal days 10–11). We recorded diaphragm EMG over the subsequent 2 h and saw a 20–30% decrease in interburst interval (Te) at 20–80 min post-injection in LPS-instilled animals with no significant change in Ti. In contrast, IL-1β injections into the nTS of en bloc in vitro brainstem–spinal cord preparations from 0 to 5 day-old pups maintained Ti and caused an increase in Te as early as 20 min later, decreasing frequency for 80–120 min after injection. Our results suggest that the neonatal respiratory response to the cytokine IL-1β mediated inflammatory response depends on the site of the inflammatory stimulus and that the direct effect of IL-1β in the nTS is to slow rather than increase rate.
Synthesis, lattice structure, and band gap of ZnSnN2

We report the synthesis of a direct gap semiconductor, ZnSnN2, by a plasma-assisted vapor–liquid–solid technique. Powder X-ray diffraction measurements of polycrystalline material yielded lattice parameters in good agreement with predicted values. Photoluminescence efficiency at room temperature was observed to be independent of excitation intensity between 103 and 108 W/cm2. The band gap was measured by photoluminescence excitation spectroscopy to be 1.7 ± 0.1 eV. The range of direct band gaps for the Zn(Si,Ge,Sn)N2 alloys is now predicted to extend from 4.5 to 1.7 eV, opening up this little-studied family of materials to a host of important applications.
Canopy Nitrogen Reserves: Impact on Soybean Yield and Seed Quality Traits in Northern Latitudes

Soybean [Glycine max (L.) Merr.] seed produced in the upper Midwest of the United States is lower in protein concentration than soybean produced throughout much of the Corn Belt, the southern United States, and Brazil. As protein comprises on average more than 400 g kg -1 of the soybean seed, yields in northern latitudes may be limited by seed protein accrual. Our objective was to examine the role of canopy N reserves at maximum vegetative growth (R5.5) on seed yield, and seed protein, oil, and sulfur concentrations in the upper Midwest. Six commercial cultivars with similar yield potentials and maturities were grown in 10 central Minnesota environments. Mean cultivar seed yields ranged from 3.1 to 3.2 Mg ha -1 , while mean environment yields ranged from 1.7 to 5.0 Mg ha -1 . High-yielding environments produced soybean plants with greater R5.5 canopy N reserves and total dry matter (DM) and seed with low protein and S concentration. Mean R5.5 canopy N quantities ranged from 117 to 309 kg ha -1 . These quantities were sufficient to satisfy seed N requirements which ranged from 43 to 91 kg ha -1 . While R5.5 canopy N and DM may have a positive influence on seed yields in these upper Midwestern environments, seed protein concentration effects appear to be mediated through effects on seed yield. A positive correlation between yield and seed N to S ratio noted here indicates that sulfur may be more limited than protein at high yield levels. Oil concentration was not affected by yield.
Nucleic acid-based methods for the detection of cancer

Continued elucidation of the genetic changes that drive cancer progression is yielding new and potentially powerful nucleic acid-based markers of neoplastic disease. Pilot studies indicate that these markers can be used to detect cancer cells in a variety of clinical settings with unprecedented precision. Nucleic acid-based markers may prove to be valuable tools for early detection of cancer in asymptomatic individuals, for confirmation or exclusion of a cancer diagnosis that is based on suspicious but nondiagnostic clinical material, for assessment of tumor burden in cancer patients, and for assessment of response to preventive approaches applied to healthy individuals who are at high risk of developing cancer. Examples of these markers, their potential applications, and the current practical limitations on their clinical use are reviewed here.
Does growth hormone influence the severity of phosphopenic rickets

The severity of bone disease in phosphopenic rickets is not correlated with serum phosphate levels. In order to determine whether growth hormone (GH) secretion may influence rachitic changes, we evaluated the 24 h integrated concentration of growth hormone (IC-GH) in five children with phosphopenic rickets. Two patients with marked clinical and roentgenographic rachitic abnormalities had normal IC-GH levels. In contrast, three patients with low IC-GH levels had mild rachitic changes. We suggest that the level of spontaneous GH secretion may be one factor which influences the severity of phosphopenic rickets.
The effect of hydrogen solubility on the internal friction of VTi alloys

The purpose of this note is to present results of low frequency internal friction measurements on three hydrogenated V-Ti alloys which illustrate how the internal friction spectrum changes from one dominated by hydride precipitation to one dominated by hydrogen in solution. Demonstrates how damping due to hydrogen changes in b.c.c. alloys as the hydrogen terminal solid solubility increases. Low solubility alloys exhibit a broad damping peak at temperatures that can be associated with hydride precipitation. As the hydrogen solubility increases, peaks due to hydride precipitation and hydrogen in solid solution can co-exist in the alloy, or as in the case for the V-10 at .% Ti alloy containing 2.3 at .% H, only the low temperature hydrogen damping will occur.
Ride and stability analysis of a sports car using multibody dynamic simulation

This paper summarizes the joint coordinate formulation for automatic generation of the equations of motion for dynamic analysis of multibody systems. A computer program based on this formulation is used to model a sports car and simulate its dynamic response in several driving scenarios. The model contains necessary elements of the suspension system such as the leafsprings, shock absorbers, bushings, tie rods, and roll stabilizer bars. An analytical model of the pneumatic tires is incorporated in the model to determine all of the necessary interacting forces and moments between a tire and the road. Results from some selected simulations are shown.
Making creative metaphors: The importance of fluid intelligence for creative thought

The relationship between intelligence and creativity remains controversial. The present research explored this issue by studying the role of fluid intelligence (Gf) in the generation of creative metaphors. Participants (n = 132 young adults) completed six nonverbal tests of Gf (primarily tests of inductive reasoning) and were then asked to create metaphors that described a past emotional experience. The metaphors were rated for creative quality. Latent variable models found that Gf explained approximately 24% of the variance in metaphor quality (standardized beta = .49), consistent with the view that creative ideation engages executive processes and abilities. The effect of Gf remained substantial after including personality (the Big Five factors) in the model. The discussion considers implications for the debate over intelligence and creativity as well as for the cognitive abilities involved in metaphor production.
Solid state extrusion of vinylidene fluoride (VF2)/vinylidene trifluoride (VF3) copolymers. II: Structure development

Copolymers of vinylidene fluoride (VF2) and vinyltrifluoride (VF3) exhibit Curie transition temperatures well below their melting points. Above these endothermic transitions, they soften and this behavior helps in their solid state extrudability. In this paper, the effects of extrusion speed, temperature, and draw ratio on structure development in 60/40 and 72/28 VF2/VF3 copolymer compositions are presented. With the increase of extrusion draw ratio the Curie transition temperature of the extrudates decreased and melting temperature increased. This behavior suggested that the chains in the crystalline regions contain higher levels of conformational defects while overall crystallinity is increased. Unoriented polymers were optically opaque and extrudates were found to be transparent as a result of breakdown on the superstructural level which decreases the scattering effects in the visible wavelength range. The micro beam WAXS studies on the samples taken from the entrance of the dies revealed that the unoriented core is surrounded by alternating unoriented and oriented layers close to the core. The remainder of the skin layers are found to be oriented with local symmetry axes and main chain orientation being parallel to the die wall surface. The regions that are found to be oriented were also found to be optically translucent and unoriented regions were optically opaque. This structure turns uniformly transparent–and thus oriented‒as the polymer enters the die. The existence of layered structure suggests that highly localized yielding occurs during early states of deformation at the converging entrance region of the die. Examination of the radial structural variation in extrudates with micro beam X-ray diffraction technique revealed that the local symmetry axes are tilted away from the extrusion direction and this tilt angle reduces at the sample macro-symmetry axis at the core of the samples. This indicated that the tilted structure developed at the converging entrance region is partially preserved through the die. While the orientation of local symmetry axes varies from skin to core in the extrudates, the orientation of chains with respect to these local symmetry axes remains relatively unaffected.
Information cartography: A proposed model for access to heterogeneous end-user databases.

Maps are among our best information systems. They require little documentation and are commonly used and understood. In contrast, many systems of classification seem to lack this acceptance and ease ofuse. Anecdotal evidence suggests that this is particularly true of the way collections of databases are classified for online browsing on library Web sites. This paper argues that some ofthe characteristics that make maps easily usable can be applied to collections of databases. Those characteristics include logical grouping of information, the ability to move smoothly between levels ofdata, and consistent amounts of data at different levels of representation.
The Facilitator Behavior Index.

-The purpose of this study was to develop an instnunent which might identify, in more than a global way, persons having attributes of a group facilitator judged effective by both his peers and superiors. A pilot instrument was developed, administered and tested against currently available global rating measures in two independent trials. The factor analysis indicated that three main attributes make independent contributions to the judged effectiveness of an encounter group facilitator: ( a ) generalized interpersonal sensitivity, (b) ability to express spontaneously a full range of emorions and feelings, (c) nondirective leadership style. The scale developed is seen as a useful feedback tool to aid in group-facilitator training, as well as a promising evaluation technique. A finding of this study would Lead one to wonder about the effect of group consensus as a method of rating the effectiveness of group facilitators.
Urogenital abnormalities produced in rat fetuses with chlorcyclizine.

Chlorcyclizine was given to pregnant rats in daily doses of 60 or 80 mg/kg on days 12-16 of gestation. The lower dose induced hydronephrosis and hydroureter in 37% of fetuses and undescended testes in 55% of the males whereas at the higher dose only 4% were hydronephrotic although 100% of the males were cryptorchid. Histological examination revealed the hydronephrosis and hydroureter to be secondary to either ureteral aplasia or persistence of the ureteropelvic membrane. The same membrane was observed in fetuses exposed to the higher dose although hydronephrosis was infrequent in these animals. Sections revealed dysplasia, tubular disorganization, and increased connective tissue in most kidneys from fetuses treated with the higher dose. A hypothesis to explain these findings is that the ureteropelvic membrane or atresia is present at both doses but urine production is reduced at the higher dose and thus no hydronephrosis results.
Exclusion of SP-C, but not SP-B, by gel phase palmitoyl lipids

The interactions of the hydrophobic pulmonary surfactant proteins, SP-C and SP-B, with lipid bilayers were assessed by fluorescence energy transfer. SP-C and SP-B were labeled with the fluorescent probe, succinimidyl nitrobenzoxadiazolyl amino hexanoate (NBD). Fluorescence energy transfer from NBD-SP-C and NBD-SP-B to four distinct indocarbocyanine probes (CnDiI) was utilized to determine the association of the surfactant proteins with various lipid acyl chains. In lipid mixtures including DPPC and DPPG, SP-C was associated with shorter chain and unsaturated lipids below the bulk lipid phase transition. Longer chain saturated CnDiI were excluded from SP-C aggregates. In contrast, SP-B demonstrated little acyl chain preference. The association of SP-C with shorter chain and unsaturated lipids below the bulk phase transition is interpreted to arise from a mismatch in the length of the hydrophobic region of the SP-C alpha-helix relative to the length of the hydrophobic region of dipalmitoyl lipids in the gel phase.
A numerical study of transient fatigue crack growth by use of an irreversible cohesive zone model

Abstract Transient fatigue crack growth is studied for a material system in which the crack tip is shielded due to crack bridging. The process of material separation during fatigue crack growth is described by the use of an irreversible cohesive zone model. In contrast to past developments of cohesive zone models, the traction–separation behavior does not follow a predefined path, but is dependent on the evolution of the damage dependent cohesive zone properties. The model definition is given and the basic uniaxial response of the model documented. The cohesive zone model is subsequently applied in a numerical study of transient fatigue crack growth. Single overload cases are computed to demonstrate the effects of variations in the cohesive zone properties. Block loading sequences with variations in the amplitude and the load ratio are computed. Model predictions qualitatively compare well to experimentally observed effects of fatigue crack growth transients in materials with crack bridging zones.
Self-monitoring as a moderator of the relationships between personality traits and performance.

This study examined the hypothesis that self-monitoring moderates the relationship between Big Five personality traits and interpersonal performance. The findings from a sample of 102 employed Executive MBA students reveal that when self-monitoring was high the relationships between 3 of the Big Five personality traits (Extraversion, Emotional Stability, and Openness to Experience) and supervisory ratings of interpersonal performance were attenuated. These effects were replicated using peer ratings of interpersonal performance for Extraversion and Emotional Stability but not for Openness to Experience. Further, as expected, self-monitoring did not moderate the relationships between personality traits and supervisory or peer ratings of task performance. Implications for future research in the area of personality and other motivational theories are discussed.
Deep Brain Stimulation: Description and Implications for Motor Speech

Abstract Purpose: Deep brain stimulation (DBS) is a surgical option which has been demonstrated to be effective for treatment of many symptoms in several movement disorders. The purpose of this paper is to describe this surgical option and to discuss its effects on motor speech. Method: The literature is reviewed to provide a summary of the information available to describe DBS surgery and its effects on motor speech in neurological disorders. Primary focus is placed on DBS as a treatment for Parkinson's disease (PD) and Essential Tremor (ET). Results and Conclusions: DBS surgery is a relatively low-risk, common, and reversible surgery used to treat the motor symptoms in many movement disorders, especially PD and ET. It is not currently used as a treatment for any motor speech disorder. Dysarthria is a commonly reported side-effect of bilateral more than unilateral DBS surgery. The reported frequency of motor speech difficulties varies, and few studies have specifically examined motor speech with reliable...
Properties of a Homologous Series of o-Hydroxy Substituted Anils and Some Binary Mixtures

Abstract In an earlier report,(1) an o-hydroxy substituted analog (OHMBBA) of the room temperature nematic N-(p-methoxybenzylidene)-p-n-butylaniline (MBBA) was prepared, and intramolecular hydrogen bonding was found to stabilize the compound against cleavage of the anil linkage. To examine the properties of this class of compounds, the synthesis of several such o-hydroxy substituted compounds was undertaken, and their liquid crystalline properties determined. Two broad temperature range binary systems were also examined consisting of OHMBBA mixed with N-(p-ethoxybenzylidene)-p-n-butylaniline (EBBA), and OHMBBA mixed with N-(p-methoxybenzylidene)-p-n-pentylaniline (MPBA) and their phase diagrams determined. The dynamic scattering behavior of one of these binaries—50-50 OHMBBA-EBBA—was examined.
Non-Inference: An Information Flow Control Model for Location-based Services

This paper presents a framework for preserving location privacy without affecting location accuracy. In this framework, services migrate a piece of code to a trusted server, which is assumed to have location information of all the interesting subjects. The code executes on the trusted server, reads location information and sends back results. We introduce Non-inference, a novel information-flow control model that guarantees that the code does not leak exact location information. We discuss the design, implementation and evaluation of a static program analysis technique that enforces non-inference for location based services.
FORGETTING AND CONDITIONED SUPPRESSION: ROLE OF A TEMPORAL DISCRIMINATION1

Several experiments have found complete retention of conditioned suppression when overall suppression to the signal for shock was measured. The present experiment examined retention of conditioned suppression but did so with a paradigm that produced temporal discrimination of shock occurrence. Nine rats were exposed to a flashing light signal of 5-min duration that always terminated with a shock. After several months, a temporal discrimination was well established, as shown by maximum suppression toward the end of the signal period. After remaining in the home cage for 25 days, the rats were again subjected to the conditioning procedure. The overall level of suppression remained the same but the temporal discrimination was not observed.
Effects of Talker Variability on Vowel Recognition in Cochlear Implants

Purpose To investigate the effects of talker variability on vowel recognition by cochlear implant (CI) users and by normal-hearing (NH) participants listening to 4-channel acoustic CI simulations. ...
Anesthetic management for the pediatric patient undergoing deep hypothermic circulatory arrest.

Early definitive repair of complex congenital heart defects is now advocated. For the completion of many of these repairs, the use of deep hypothermic circulatory arrest (DHCA) is an absolute neces...
Polynitrosylated proteins: characterization, bioactivity, and functional consequences

Abstract Chemical modification of proteins is a common theme in their regulation. Nitrosylation of protein sulfhydryl groups has been shown to confer nitric oxide (NO)-like biological activities and to regulate protein functions. Several other nucleophilic side chains -- including those with hydroxyls, amines, and aromatic carbons -- are also potentially susceptible to nitrosative attack. Therefore, we examined the reactivity and functional consequences of nitros(yl)ation at a variety of nucleophilic centers in biological molecules. Chemical analysis and spectroscopic studies show that nitrosation reactions are sustained at sulfur, oxygen, nitrogen, and aromatic carbon centers, with thiols being the most reactive functionality. The exemplary protein, BSA, in the presence of a 1-, 20-, 100-, or 200-fold excess of nitrosating equivalents removes 0.6 +/- 0.2, 3.2 +/- 0.4, 18 +/- 4, and 38 +/- 10, respectively, moles of NO equivalents per mole of BSA from the reaction medium; spectroscopic evidence shows the proportionate formation of a polynitrosylated protein. Analogous reaction of tissue-type plasminogen activator yields comparable NO protein stoichiometries. Disruption of protein tertiary structure by reduction results in the preferential nitrosylation of up to 20 thus-exposed thiol groups. The polynitrosylated proteins exhibit antiplatelet and vasodilator activity that increases with the degree of nitrosation, but S-nitroso derivatives show the greatest NO-related bioactivity. Studies on enzymatic activity of tissue-type plasminogen activator show that polynitrosylation may lead to attenuated function. Moreover, the reactivity of tyrosine residues in proteins raises the possibility that NO could disrupt processes regulated by phosphorylation. Polynitrosylated proteins were found in reaction mixtures containing interferon-gamma/lipopolysaccharide-stimulated macrophages and in tracheal secretions of subjects treated with NO gas, thus suggesting their physiological relevance. In conclusion, multiple sites on proteins are susceptible to attack by nitrogen oxides. Thiol groups are preferentially modified, supporting the notion that S-nitrosylation can serve to regulate protein function. Nitrosation reactions sustained at additional nucleophilic centers may have (patho)physiological significance and suggest a facile route by which abundant NO bioactivity can be delivered to a biological system, with specificity dictated by protein substrate.
Trips to Fantasy Island: Contexts of Risky Sex for San Francisco Gay Men:

The paper presents a qualitative analysis of sexual episodes reported in the context of in-depth interviews with gay men in San Francisco. The analysis is based not on comparisons between individuals or groups, but rather on comparisons between sexual episodes - protected and unprotected, risky and safe - within individuals' sexual lives. The analysis revealed a convergence of six important factors in risky sexual encounters, including negative emotional states prior to the encounters, sex under the influence of drugs and/or alcohol, and low perceptions of sexual control. The findings suggest that individuals come to sexual encounters in search of experiences other than simply sex, such as interpersonal connection, social acceptance or emotional release. In those cases where the need for connectedness, affirmation, or self-worth is so great and deeply felt, individuals' usual concern for sexual safety and health seems to be overpowered.