cssi/SciSciGPT-SciSciNet huggingface dataset:
Metformin-Induced Killing of Triple Negative Breast Cancer Cells is Mediated by Reduction in Fatty Acid Synthase via miRNA-193b

The anti-diabetic drug metformin (1,1-dimethylbiguanide hydrochloride) reduces both the incidence and mortality of several types of cancer. Metformin has been shown to selectively kill cancer stem cells, and triple-negative breast cancer (TNBC) cell lines are more sensitive to the effects of metformin as compared to luminal breast cancer. However, the mechanism underlying the enhanced susceptibility of TNBC to metformin has not been elucidated. Expression profiling of metformin-treated TNBC lines revealed fatty acid synthase (FASN) as one of the genes most significantly downregulated following 24 h of treatment, and a decrease in FASN protein was also observed. Since FASN is critical for de novo fatty acid synthesis and is important for the survival of TNBC, we hypothesized that FASN downregulation facilitates metformin-induced apoptosis. Profiling studies also exposed a rapid metformin-induced increase in miR-193 family members, and miR-193b directly targets the FASN 3'UTR. Addition of exogenous miR-193b mimic to untreated TNBC cells decreased FASN protein expression and increased apoptosis of TNBC cells, while spontaneously immortalized, non-transformed breast epithelial cells remained unaffected. Conversely, antagonizing miR-193 activity impaired the ability of metformin to decrease FASN and cause cell death. Further, the metformin-stimulated increase in miR-193 resulted in reduced mammosphere formation by TNBC lines. These studies provide mechanistic insight into metformin-induced killing of TNBC.
A contrast‐detail analysis of diagnostic ultrasound imaging

For diagnosticultrasound imaging, as in computed tomography, a feature of prime importance is the detection of focal lesions of varying size and contrast (echo amplitude) from surrounding tissue. This study describes a new tissue‐simulating phantom which has been used to measure the threshold detection of varying contrast, simulated lesions. The phantom consists of a block of tissue‐mimicking gelatin which contains a row of conical targets at a depth of 7 cm. Each cone contains a different tissue‐mimicking material so that the echo amplitude of the cones relative to the background material covers a dynamic range of 20 dB. Cross‐sectional B‐scans, perpendicular to the lengths of the cones, result in images of disks of constant diameter but varying contrast. Parallel cross‐sectional scans yield ‘‘lesions’’ varying in diameter from 20 to 1 mm. Relative contrast of the cones vs background tissue is obtained by varying scattering particle sizes from 90 to 300 μm. UltrasoundB‐scans of the phantom were examined by medical physicist observers to determine threshold detection of lesions as a function of size and contrast. The results indicate that detection of high contrast targets is limited by the imaging system’s spatial resolution. Detection of low contrast targets is limited by the image speckle, i.e., coherent noise.
Polymer coatings as separator layers for microbial fuel cell cathodes

Abstract Membrane separators reduce oxygen flux from the cathode into the anolyte in microbial fuel cells (MFCs), but water accumulation and pH gradients between the separator and cathode reduces performance. Air cathodes were spray-coated (water-facing side) with anion exchange, cation exchange, and neutral polymer coatings of different thicknesses to incorporate the separator into the cathode. The anion exchange polymer coating resulted in greater power density (1167 ± 135 mW m−2) than a cation exchange coating (439 ± 2 mW m−2). This power output was similar to that produced by a Nafion-coated cathode (1114 ± 174 mW m−2), and slightly lower than the uncoated cathode (1384 ± 82 mW m−2). Thicker coatings reduced oxygen diffusion into the electrolyte and increased coulombic efficiency (CE = 56–64%) relative to an uncoated cathode (29 ± 8%), but decreased power production (255–574 mW m−2). Electrochemical characterization of the cathodes ex situ to the MFC showed that the cathodes with the lowest charge transfer resistance and the highest oxygen reduction activity produced the most power in MFC tests. The results on hydrophilic cathode separator layers revealed a trade off between power and CE. Cathodes coated with a thin coating of anion exchange polymer show promise for controlling oxygen transfer while minimally affecting power production.
The Integral Form of the Equation of Radiative Transfer for an Inhomogeneous, Anisotropically Scattering, Solid Sphere

Etablissement de la forme integrale de l'equation du transfert radiatif de chaleur dans une sphere solide constituee d'un milieu heterogene a diffusion anisotrope avec des sources de tenues de chaleur soumise a un rayonnement externe et presentant une surface a reflexion speculaire ou diffuse
Responses of native and migrant desert residents to arid heat

Four groups of Sonoran Desert residents were compared in three studies of heat tolerance. In the first two studies the task involved walking in arid heat at a moderate rate (5 km/hour) for two hours per day over a period of seven consecutive days. The first study compared seven Yaqui Indians with ten Mestizos, all lifelong residents of the same neighborhood in Hermosillo, Sonora. The groups showed no significant differences in physiological responses. The second study compared five Papago Indian students with five White students from Tucson, Arizona. The Papago showed significantly lower sweat rates and significantly lower rectal temperatures. None of the groups showed sequential changes which could be called acclimatization. The lower sweat rate of the Papago is partially the result of their smaller size, but their lower rectal temperatures may represent a more effective heat dissipating mechanism. The third study compared naturally acclimatized Yaquis and Mestizos in hot, humid conditions established by other investigators. These well acclimatized subjects responded in a manner intermediate between the unacclimatized and artificially acclimatized Caucasians reported in the literature. Thus desert acclimatization does not confer maximal acclimatization to humid heat.
Practical synthetic approaches to intermediates for the preparation of the novel O-sulfonated-N-hydroxy-2-azetidinone antibiotics

Abstract A practical synthesis of intermediates useful for the preparation of a variety of monocyclic β-lactam antibiotics is described. Hydroxaminolysis of N-protected serine esters provided the hydroxamic acids 10 . Acylation followed by cyclization yielded the β-lactams 12 . Solvolytic deacylation gave the parent N-hydroxy-2-azetidinones 7 which can be converted to the N- unsubstituted 2-azetidinones 8 or the novel O-sulfonated antibiotics 3 . The N-unsubstituted-2-azetidinones 8 are also useful for the preparation of the nocardicins and the monobactams.
Ohio Hopewell Archaeoastronomy: A Meeting of Earth, Mind, and Sky

AbstractWithin archaeoastronomy, phenomenological approaches including landscape archaeology, actualization studies, use of geographic information systems (GIS), and operational sequence analysis inform our understanding of prehistoric practices. Monumental earthworks in Ohio (USA) dating to 2000 BP—the Hopewell geometric enclosures—are examined by these means. The matrix of landscape viewshed and celestial dome shape human production of local cosmogonies, becoming encoded across the terrain by indexical sightlines and functional and ritual architectures. The resultant array of calendrical alignments defines a suite of horizon foresights on the surrounding skyline, whose premised archaeological presence/absence provides a hypothetico-deductive test in a field of study where such evidence is often lacking. While accurate calendrical sightlines were likely used for subsistence and other scheduling, a spectrum of sensory stimuli would accompany observations and associated ritual performances. Light, color, a...
Self-efficacy in the context of online learning environments: A review of the literature and directions for research

The purpose of this paper is to examine the construct of self-efficacy in the context of online learning environments. Self-efficacy is defined as “beliefs in one's capabilities to organize and execute the courses of action required to produce given attainments” (Bandura, 1997, p. 3). Traditionally, the four main sources of self-efficacy development are enactive master experiences, vicarious experiences, verbal persuasion, and physiological and affective state (Bandura, 1997). In this paper, self-efficacy is introduced in general. Research related to academic self-efficacy and self-efficacy in online learning environments is reviewed. The study of self-efficacy in online learning environments is new relative to the construct of self-efficacy. Research on self-efficacy and the use of computers in instructional situations has been included to broaden the literature base. The development of self-efficacy beliefs in online environments is highlighted as well as self-efficacy assessment issues. Possible areas of self-efficacy research in online environments are suggested, including pedagogical agents, persuasive feedback, and self-efficacy assessment.
The Olduvai giant hominid tooth.

THE giant molar tooth found by Dr. L. S. B. Leakey1 in Bed II at Olduvai Gorge in Tanganyika was reported by him1,2 to be a lower deciduous second molar of a hominid, possibly related to Sinanthropus and Homo heidelbergensis. This interpretation has been questioned by a number of workers including G. H. R. von Koenigswald3 of Utrecht and John T. Robinson4 of Pretoria, who conclude that the tooth is rather a permanent upper molar, probably Australopithecine.
Sensitivity of L-(-)2,3-dideoxythiacytidine resistant hepatitis B virus to other antiviral nucleoside analogues.

Abstract l -(-)2′,3′-Dideoxythiacytidine ( l (-)SddC, Lamivudine) resistant hepatitis B virus (HBV) develops in patients after prolonged treatment. Point mutations detected in the viral genome from these patients have been shown to be responsible for l (-)SddC resistance. Therefore, new drugs active against l (-)SddC resistant HBV are needed. Using a transient transfection system, we studied the sensitivity of l (-)SddC resistant HBV to other anti-HBV nucleoside analogues. It was found that the L526M mutation alone caused greater resistance to penciclovir (PCV) than did the V553I mutation alone. Both mutations also caused the virus to be less sensitive to l (-)SddC and 2′-fluoro-5-methyl-β- l -arabinofuranosyluracil ( l -FMAU), although the degree of resistance was much less than that to PCV. The A546V mutation had no impact on the sensitivity to l (-)SddC, l -FMAU, and PCV. When these single mutations were coupled with the M550V/I mutation, all the double mutants were resistant to those drugs. Although 2′,3′-dideoxy-2′,3′-didehydro-β- l (-)-5-fluorocytidine ( l (-)Fd4C) was also less active, the ic 50 of l (-)Fd4C against the l (-)SddC resistant mutant was at least fifty times lower than that against cell growth in culture. DNA polymerase associated with l (-)SddC resistant virions was also found to be less sensitive than that with wild-type HBV to those l- nucleoside triphosphates. All the l (-)SddC resistant mutants were still sensitive to 9-(2-phosphonylmethoxyethyl)-adenine (PMEA). These results suggest that different mutations in the HBV genome have a different impact on its sensitivity to those compounds, and l (-)SddC resistant HBV may also be resistant to PCV, l -FMAU, and l (-)Fd4C. A nucleoside analogue less toxic than PMEA could be developed against l (-)SddC resistant HBV.
Atherosclerosis of the ascending aorta is an independent predictor of long-term neurologic events and mortality.

Abstract OBJECTIVES This study was undertaken to determine whether atherosclerosis of the ascending aorta is a predictor of long-term neurologic events and mortality. BACKGROUND Atherosclerosis of the thoracic aorta has been recently considered a significant predictor of neurologic events and peripheral embolism, but not of long-term mortality. METHODS Long-term follow-up (a total of 5,859 person-years) was conducted of 1,957 consecutive patients ≥50 years old who underwent cardiac surgery. Atherosclerosis of the ascending aorta was assessed intraoperatively (epiaortic ultrasound) and patients were divided into four groups according to severity (normal, mild, moderate or severe). Carotid artery disease was evaluated (carotid ultrasound) in 1,467 (75%) patients. Cox proportional-hazards regression analysis was performed to assess the independent effect of predictors on neurologic events and mortality. RESULTS A total of 491 events occurred in 472 patients (neurologic events 92, all-cause mortality 399). Independent predictors of long-term neurologic events were: hypertension (p = 0.009), ascending aorta atherosclerosis (p = 0.011) and diabetes mellitus (p = 0.015). The independent predictors of mortality were advanced age (p 1.5-fold increase in the incidence of both neurologic events and mortality as the severity of atherosclerosis increased from normal-mild to moderate, and a greater than threefold increase in the incidence of both as the severity of atherosclerosis increased from normal-mild to severe. CONCLUSIONS Atherosclerosis of the ascending aorta is an independent predictor of long-term neurologic events and mortality. These results provide additional evidence that in addition to being a direct cause of cerebral atheroembolism, an atherosclerotic ascending aorta may be a marker of generalized atherosclerosis and thus of increased morbidity and mortality.
A dynamic data/currency protocol for mobile database design and reconfiguration

This paper presents flexible protocols for dynamic database design and reconfiguration, enabling mobile database to be designed in such a way that data location, replication and even use semantics can be changed dynamically. In particular, a dual data/currency hoarding and synchronization protocol, a metadata protocol and currency redistribution protocol are proposed. Metadata records the changing characteristics of replicas and currencies are dynamically redistributed to fit the target. Primaries may be diluted, concentrated and transferred in the system. Traditional distributed database is included as home of data. An ad-hoc database may check out its desired data/currency and check them back in when they are no longer accessed by the mobile users. We demonstrate that the flexibility of this approach can significantly improve commit performance under dynamic access and mobility behavior.
Double pulsed particle image velocimeter with directional resolution for complex flows

An automated particle image velocimeter has been constructed to determine fluid velocity fields by directly measuring particle image separations. A new image shifting technique eliminates directional ambiguity from velocity measurements. Theoretical and practical considerations in implementing the PIV system are presented. Using a simple, known flow field to investigate system performance, RMS errors of less than 0.7% of full scale are achieved, and at low seeding density fewer than 10% of velocity measurements produce bad data. Applications of system measurements to the instantaneous velocity field of an axisymmetric jet are presented.
Defending (a modified version of) the Zygote Argument

Think of the last thing someone did to you to seriously harm or offend you. And now imagine, so far as you can, becoming fully aware of the fact that his or her action was the causally inevitable result of a plan set into motion before he or she was ever even born, a plan that had no chance of failing. Should you continue to regard him or her as being morally responsible—blameworthy, in this case—for what he or she did? Many have thought that, intuitively, you should not. Recently, Alfred Mele has employed this line of thought to mount what many have taken to be a powerful argument for incompatibilism: the “Zygote Argument”. However, in interesting new papers, John Martin Fischer and Stephen Kearns have each independently argued that the Zygote Argument fails. As I see it, the criticisms of Fischer and Kearns reveal some important questions about how the argument is meant to be—or how it would best be—understood. Once we make a slight (but important) modification to the argument, however, I think we will be able to see that the criticisms of Fischer and Kearns do not detract from its substantial force.
Optimal reconfiguration sequence management

In this paper, we present an efficient optimal algorithm for minimizing runtime reconfiguration (context switching) delay of executing an application on a reconfigurable system. We assume that the basic operations of the application are already scheduled and each of them has to be realized on the reconfigurable fabric in order to be executed. The modeling and algorithm are both applicable to partially reconfigurable platforms as well as Multi-FPGA systems. The algorithm can be directly applied to minimize the application runtime for many typical classes of applications, where the actual execution delay of basic operations is negligible compared to reconfiguration delay. We prove the optimality and efficiency of our algorithm and report experimental results, which demonstrate 40% to 2.5% improvement in total runtime reconfiguration delay.
The Crutch and the Scepter: Mephibosheth and David

This sermon was preached at the conclusion of a 2-day conference on making a place in faith communities for people with disabilities. The first part is an exposition of the story of Mephibosheth, an Israelite prince whose legs were injured in a childhood mishap, rendering him lame for life. Three applications of this story for contemporary faith communities are then made: 1) Faithful and effective ministry to and with persons with disabilities recognizes that them as full members of the faith community, not as charity projects. Persons with disabilities should be treated like other church members—with dignity, respect, easy naturalness, and a minimum of fuss. 2) Faithful and effective ministry to persons with disabilities includes ministry to their caregivers, both family members and professions. 3). Faithful and effective ministry to persons with disabilities avoids the temptation of speaking for or about them, and helps them speak for themselves.
Graphene and boron nitride lateral heterostructures for atomically thin circuitry

Precise spatial control over the electrical properties of thin films is the key capability enabling the production of modern integrated circuitry. Although recent advances in chemical vapour deposition methods have enabled the large-scale production of both intrinsic and doped graphene, as well as hexagonal boron nitride (h-BN), controlled fabrication of lateral heterostructures in these truly atomically thin systems has not been achieved. Graphene/h-BN interfaces are of particular interest, because it is known that areas of different atomic compositions may coexist within continuous atomically thin films and that, with proper control, the bandgap and magnetic properties can be precisely engineered. However, previously reported approaches for controlling these interfaces have fundamental limitations and cannot be easily integrated with conventional lithography. Here we report a versatile and scalable process, which we call 'patterned regrowth', that allows for the spatially controlled synthesis of lateral junctions between electrically conductive graphene and insulating h-BN, as well as between intrinsic and substitutionally doped graphene. We demonstrate that the resulting films form mechanically continuous sheets across these heterojunctions. Conductance measurements confirm laterally insulating behaviour for h-BN regions, while the electrical behaviour of both doped and undoped graphene sheets maintain excellent properties, with low sheet resistances and high carrier mobilities. Our results represent an important step towards developing atomically thin integrated circuitry and enable the fabrication of electrically isolated active and passive elements embedded in continuous, one-atom-thick sheets, which could be manipulated and stacked to form complex devices at the ultimate thickness limit.
Charge-induced asymmetrical displacement of an aligned carbon nanotube buckypaper actuator

Abstract Randomly dispersed carbon nanotube buckypaper (BP) actuation in open air, ambient conditions was shown to correlates well with the carbon–carbon bond length changes due to charge and discharge. The displacement of magnetically aligned BP actuators applied with a positive voltage was 450% higher than that for an applied negative voltage, which verifies the asymmetrical deformation characteristics of nanotube actuation. Charge-injected actuation of aligned BP can produce a 0.22% strain by applying a high voltage (1100 V). The aligned BP actuators exhibited a higher strain than did randomly dispersed BP actuators. The aligned BP actuators showed stable and fast responses under ambient, open air conditions without electrolytes, which offers direct experimental verification that BP actuation comes directly from carbon–carbon bond deformation due to charge and discharge processes. The nanotube BP actuators demonstrated a much faster response compared to other polymer-based actuators.
Identification and characterization of a unique adenosine kinase from Mycobacterium tuberculosis.

Adenosine kinase (AK) is a purine salvage enzyme that catalyzes the phosphorylation of adenosine to AMP. In Mycobacterium tuberculosis, AK can also catalyze the phosphorylation of the adenosine analog 2-methyladenosine (methyl-Ado), the first step in the metabolism of this compound to an active form. Purification of AK from M. tuberculosis yielded a 35-kDa protein that existed as a dimer in its native form. Adenosine (Ado) was preferred as a substrate at least 30-fold (Km = 0.8 ± 0.08 μM) over other natural nucleosides, and substrate inhibition was observed when Ado concentrations exceeded 5 μM. M. tuberculosis and human AKs exhibited different affinities for methyl-Ado, with Km values of 79 and 960 μM, respectively, indicating that differences exist between the substrate binding sites of these enzymes. ATP was a good phosphate donor (Km = 1100 ± 140 μM); however, the activity levels observed with dGTP and GTP were 4.7 and 2.5 times the levels observed with ATP, respectively. M. tuberculosis AK activity was dependent on Mg2+, and activity was stimulated by potassium, as reflected by a decrease in the Km and an increase in Vmax for both Ado and methyl-Ado. The N-terminal amino acid sequence of the purified enzyme revealed complete identity with Rv2202c, a protein currently classified as a hypothetical sugar kinase. When an AK-deficient strain of M. tuberculosis (SRICK1) was transformed with this gene, it exhibited a 5,000-fold increase in AK activity compared to extracts from the original mutants. These results verified that the protein that we identified as AK was coded for by Rv2202c. AK is not commonly found in bacteria, and to the best of our knowledge, M. tuberculosis AK is the first bacterial AK to be characterized. The enzyme shows greater sequence homology with ribokinase and fructokinase than it does with other AKs. The multiple differences that exist between M. tuberculosis and human AKs may provide the molecular basis for the development of nucleoside analog compounds with selective activity against M. tuberculosis.
Effect of amino acid imbalances on the stimulatory effect of L-tryptophan on hepatic protein synthesis

Earlier it was reported that mice or rats tube-fed a single feeding of L-tryptophan (TRP) demonstrated a stimulation of hepatic protein syn thesis. The present study was concerned with whether dietary imbalances induced by tube-feeding different ratios of L-alanine (ALA) or L-leucine (LEU) in relation to TRP would affect TRP's stimulatory effect on hepatic protein synthesis. Male Swiss mice, food-deprived overnight, were tube-fed one feeding of solution keeping TRP constant and varing ratios of ALA/TRP of 0.4, 2.1, or 4 or ratios of LEU/TRP of 4.8, 7.2, or 9.6. After 1 h, mice were killed and protein synthesis (14C-leucine incorporation into proteins in vitro using microsomes of livers) was measured. TRP alone stimulated hepatic protein synthesis by 83 % while ALA/TRP ratios of 2.1 or 4 but not of 0.4 and LEU/TRP ratios of 9.6 but not of 4.8 or 7.2 caused significant decreases in the stimulation of hepatic protein synthesis. Measurements of serum and hepatic free TRP concentrations in the experimental groups were similar in all groups tube-fed TRP alone or in combinations.
Association of QRS duration with left ventricular structure and function and risk of heart failure in middle‐aged and older adults: the Multi‐Ethnic Study of Atherosclerosis (MESA)

Aims Prolonged QRS duration (QRSd) on the electrocardiogram (ECG) has been associated with cardiac structural and functional abnormalities by echocardiography and an increased risk of heart failure (HF). Data are sparse on these relationships in middle-aged and elderly individuals free of baseline cardiovascular disease with respect to cardiac magnetic resonance imaging (MRI). We sought to determine whether QRSd is associated with incident HF and measures of cardiac structure and function by cardiac MRI. Methods and results We analysed baseline ECGs in the Multi-Ethnic Study of Atherosclerosis (MESA) to determine whether QRSd >100 ms was associated with incident HF. We adjusted for demographic and clinical risk factors, as well as MRI measures of left ventricular (LV) structure and function. Among 4591 eligible participants (51% women; 39% white; mean age 61 years), 75 developed incident HF over a mean follow-up of 7.1 years. QRSd >100 ms was significantly associated with MRI measures of cardiac structure and function, as well as incident HF, even after adjustment for demographic covariates [hazard ratio (HR) 2.10, 95% confidence interval (CI) 1.29–3.42; P = 0.003] and clinical risk factors (HR 1.86, 95% CI 1.14–3.03; P = 0.01). With further adjustment for individual LV structural measures, findings were attenuated to non-significance. Separate adjustment for LV functional measures yielded only mild attenuation. Conclusion In middle-aged and older adults without cardiovascular disease, a QRSd >100 ms was significantly associated with incident HF. After adjustment for LV structural measures, the association was attenuated to non-significance, suggesting that prolonged QRSd is potentially a useful marker of LV structure that may predispose to HF risk.
The Effect on Vision of Light Scatter From HMD Visors and Aircraft Windscreens

The amount of scattered light, or haze, typically increases as transparent materials age, wear, become dirty, or become scratched from cleaning. Light scattered from scratched aircraft transparencies, such as windscreen, head-up-display combiners, and helmet visors, can potentially reduce pilot visual performance and reduce target detection range. Presented in this paper are the results of an investigation of light scattered from transparencies exhibiting different levels of wear and surface damage. Two methods of measuring scattered light are compared. Visual performance under conditions of white light scatter relevant to the use of helmet-mounted displays in the cockpit is also examined.
Functional Regulation of γ-Aminobutyric Acid Transporters by Direct Tyrosine Phosphorylation

Tyrosine phosphorylation regulates multiple cell signaling pathways and functionally modulates a number of ion channels and receptors. Neurotransmitter transporters, which act to clear transmitter from the synaptic cleft, are regulated by multiple second messenger pathways that exert their effects, at least in part, by causing a redistribution of the transporter protein to or from the cell surface. To test the hypothesis that tyrosine phosphorylation affects transporter function and to determine its mechanism of action, we examined the regulation of the rat brain γ-aminobutyric acid (GABA) transporter GAT1 expressed endogenously in hippocampal neurons and expressed heterologously in Chinese hamster ovary cells. Inhibitors of tyrosine kinases decreased GABA uptake; inhibitors of tyrosine phosphatases increased GABA uptake. The decrease in uptake seen with tyrosine kinase inhibitors was correlated with a decrease in tyrosine phosphorylation of GAT1 and resulted in a redistribution of the transporter from the cell surface to intracellular locations. A mutant GAT1 construct that was refractory to tyrosine phosphorylation could not be regulated by tyrosine kinase inhibitors. Activators of protein kinase C, which are known to cause a redistribution of GAT1 from the cell surface, were additive to the effects of tyrosine kinase inhibitors suggesting that multiple signaling pathways control transporter redistribution. Application of brain-derived neurotrophic factor, which activates receptor tyrosine kinases, up-regulated GAT1 function suggesting one potential trigger for the cellular regulation of GAT1 signaling by tyrosine phosphorylation. These data support the hypothesis that transporter expression and function is controlled by the interplay of multiple cell signaling cascades.
Vibrational spectroscopy of interstellar molecules

In this paper we describe how infrared vibrational spectroscopy has been applied in our laboratory to three areas of interest to interstellar chemistry: the origin of the unidentified interstellar infrared emission bands, the depletion of the iron in the interstellar medium, and the fractionation of isotope-bearing molecules in space. In the first area, infrared absorption spectra of polycyclic aromatic hydrocarbons and their ions trapped in cryogenic rare gas matrices have been analyzed and shown to coincide well with the frequencies and relative intensities of the unidentified infrared emission bands. These bands have been observed from many sources in interstellar space, including reflection and planetary nebulae and H II regions, in parts of the Milky Way, as well as other galaxies. In the second area, a free electron laser, with tunable output in the infrared, has been utilized to record resonant multiphoton photodissociation vibrational spectra of various polycyclic aromatic hydrocarbons complexed with Fe+ in a Fourier transform ion cyclotron resonance mass spectrometer. Stable complexes found for Fe+ and a number of PAHs suggest that iron could be sequestered in such species and that they could function as carriers of the unidentified infrared emission bands. In the third area, the photo-induced 13C-isotopic scrambling in the C3 carbon cluster has been investigated by matrix isolation infrared spectroscopy. Fractionation is shown to arise from small zero-point energy differences in the C3 isotopomers. A proposed mechanism of isotopic scrambling involving the formation of cyclic C3 intermediates may be applicable to other species for which isotopic fractionation has also been observed in the ISM.
Effects of ciclesonide and fluticasone propionate on allergen-induced airway inflammation and remodeling features

Background Several topical corticosteroids are available as anti-inflammatory treatment for asthma. Their comparative effects on allergic inflammation and airway remodeling are unclear. Objective We compared the effects of ciclesonide with those of fluticasone propionate in a Brown Norway rat model of chronic allergic asthma. Methods Rats sensitized and exposed to ovalbumin (OVA) were treated with dry powder vehicle, ciclesonide, or fluticasone (0.01, 0.03, and 0.1 mg/kg administered intratracheally) 24 hours and 1 hour before each of 6 OVA exposures. In a second protocol we administered 0.1 mg/kg ciclesonide or fluticasone only after the third OVA exposure. Results Ciclesonide at all doses inhibited the allergen-induced increase in airway eosinophils and T cells, reduced goblet cell hyperplasia, and decreased 5-bromo-2′-deoxyuridine–immunoreactive airway smooth muscle (ASM) and epithelial cells. At 0.03 and 0.1 mg/kg ciclesonide, bronchial hyperresponsiveness (BHR) was also inhibited. Fluticasone did not attenuate allergen-induced BHR, despite inhibiting airway eosinophils and T cells, goblet cell hyperplasia, and 5-bromo-2′-deoxyuridine–immunoreactive ASM and epithelial cells. Fluticasone (0.1 mg/kg) caused a significant reduction in body weight (9%) compared with ciclesonide (0.1 mg/kg). Ciclesonide did not change plasma corticosterone levels, whereas fluticasone (0.1 mg/kg) reduced them. In the second protocol both fluticasone and ciclesonide inhibited BHR, bronchial inflammation, goblet cell hyperplasia, and ASM proliferation. Conclusion Ciclesonide potently inhibited chronic allergic inflammation, remodeling, and BHR without having an effect on body weight and the hypothalamic-pituitary-adrenal axis. Fluticasone prevented airway inflammation but not BHR, but both fluticasone and ciclesonide are effective at reversal of BHR, inflammation, and remodeling features.
Collaboration and cogenerativity: on bridging the gaps separating theory-practice and cognition-emotion

In this rejoinder, I comment on how going through the activity of participating in this forum and of engaging in dialogue with my commentators makes sense at several levels—most importantly, at the personal and the conceptual—and how these two levels are intricately connected. The link between the personal and conceptual (cognition and emotion)—their de facto unity—is highlighted through a discussion of a theoretical stance that has to do with ineluctable dialogicality of any and all aspects, incarnations, and expressions of human development, being, and learning. The dialogicality of knowing comes to the fore if knowledge is understood as being part and parcel of ongoing real life activities out in the world imbued with ideology, values, and commitments. In this stance, knowing and acting, words and deeds, theory and practice cannot be ever thought of as separate realms; instead they inevitably and necessarily appear as belonging together and as forming inherent aspects (or dimensions) of one and the same process of people collaboratively engaging with and transforming the world.
Other Infrared (IR) Transform Spectroscopies

Profiting from the example of Fourier transform spectroscopy, a number of possible other transform spectroscopies, such as Hadamard, Walsh, and Laplace transforms, have been investigated. A number of other transforms show spectroscopic promise in the IR. (1) CHIRP. Here a tunable laser is coupled via a beamsplitter to a spatially extended sample and a heterodyne detector. The audio frequency output of the latter after chirp transformation yields a range resolved signal useful for remote measurements or nonuniform sample measurements. (2) KRAMERS-KRONIG. This transform, for which a simplified fast calculating procedure has evolved in the Fourier domain, interconverts refraction and absorption spectra. Refractive index spectra offer advantages for tunable laser work, can be used for absorption spectrum correction, and can be conveniently obtained by asymmetric FT-IR. (3) ABSORBANCE NONLINEARITY. Particle size or shape, thickness, or concentration distributions within an inhomogeneous sample can be calculated from line shape distortions produced by the energy nonlinearity of the absorption process. Other transforms of potential ability, such as the Hankel, the equiabsorbance, and two dimensional Fourier transforms, will be briefly mentioned.© (1981) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
AGING 2000: CONSUMER EMPOWERMENT THROUGH EDUCATION

Aging 2000 is a statewide, private, non-profit, grassroots organization of community-based networks of providers and consumers working to improve geriatric health care delivery through consumer empowerment. Among its programs are educational workshops led by trained volunteers on how to better one's health behaviors and navigate the current health care system. The theoretical underpinnings , range of topics covered, the utilization of older adult volunteers as educators , and evaluation outcomes of these workshops are discussed.
Parameters of activity behavior for use in travel analysis

Abstract Increasingly in the last decade, transportation researchers have begun examining travel in the context of activities which are demanded at the end of trips. Before the results of this research can be used in planning, the boundaries of activity-related behavior need to be made explicit. The research reported here helps to delineate these boundaries by developing a theoretical model of activity-related choices and exploring it using data from a conventional home interview survey. A number of the variables are used for the first time and in ways which could be incorporated into most existing transportation models. Both general data analysis and estimation of coefficients in multivariate equations are carried out. In general, the findings support the judgement made about the causal factors operating to influence the behaviors of interest: whether someone participates in an activity and if so, for how long. Further, the empirical results tend to support the division of the causal factors into the three categories of activity program/needs, temporal constraints and spatial constraints. One of the unique features of the empirical analysis is the division of the day into five time periods, each with its own associated equations to be estimated. As a result of developing this feature, the interrelatedness of a person's decisions made in the different time periods is captured. The mixed results for the variables used to proxy the effect of interdependence within a household and within a daily activity schedule show both the complex nature of the behaviors in question and the need for further research in this field.
Effects of amphetamine on reactivity to emotional stimuli

Rationale Most studies of the reinforcing effects of stimulants have focused on the drugs’ capacity to induce positive mood (i.e., euphoria). However, recent findings suggest drugs may also alter emotional reactivity to external stimuli, and that this may occur independently of direct effects on mood.
Understanding High-Temperature Superconductors with Quantum Cluster Theories

Quantum cluster theories are a set of approaches for the theory of correlated and disordered lattice systems, which treat correlations within the cluster explicitly, and correlations at longer length scales either perturbatively or within a mean-field approximation. These methods become exact when the cluster size diverges, and most recover the corresponding (dynamical) mean-field approximation when the cluster size becomes one. Here we will review systematic dynamical cluster simulations of the two-dimensional Hubbard model, that display phenomena remarkably similar to those found in the cuprates, including antiferromagnetism, superconductivity and pseudogap behavior. We will then discuss results for the structure of the pairing mechanism in this model, obtained from a combination of dynamical cluster results and diagrammatic techniques.
Parallel nonlinear dynamic finite element analysis of three-dimensional shell structures

Abstract A parallel nonlinear dynamic finite element analysis code (PANDA) which can predict the response of three-dimensional shell structures has been developed for execution on a hypercube computer. This code is implemented in conjunction with a previously developed mesh decomposition algorithm. The performance of the parallel code has been tested on a 32-processor Intel iPSC/d5 hypercube. Performance results have been obtained for a range of problems which exhibit large deformation, elastic-plastic dynamic response, including an idealized automotive lower side-rail subject to impact loading. Speedup factors of greater than 31 have been achieved when executing on 32 processors. Efficiencies of 99% have been obtained by assigning as few as eight shell elements to each processor. It is demonstrated that these high efficiencies decrease very slowly as the number of processors is increased, provided the size of the problem is appropriately scaled. Since complex finite element models may contain 10,000 or more elements, this demonstrates that massively parallel hypercube machines have enormous potential for solving these types of structural analysis problems.
Are bid preferences benign? The effect of small business subsidies in highway procurement auctions

Abstract Bid preferences in procurement auctions allow firms from an identifiable group an advantage in bidding against unfavored firms. While economic efficiency is expected to fall as a result of bid preferences, government procurement costs may either increase or decrease depending on the competitive response of favored and unfavored firms. This paper uses data from California auctions for road construction contracts, where small businesses receive a 5-percent bid preference in auctions for projects using only state funds and no preferential treatment on projects using federal aid. I show that while firms' bidding behavior matches theoretical predictions, procurement costs are 3.8 percent higher on auctions using preferences. The higher procurement cost in preference auctions is attributed to reduced participation by lower cost large firms. Structural estimates of latent firm costs are then used to evaluate how efficiency and the division of surplus between firms and the government are impacted by bid preferences. Firm profits are 3.1 percent lower under bid preferences, however this is overwhelmed by the efficiency loss due to reduced large firm participation. The efficiency loss conditional on firm participation is estimated to represent around 0.1 percent of overall procurement costs. Including the adverse effect of preferences on the participation of large firms increases the estimated efficiency loss to 3.6 percent, which represents 27 cents for each additional dollar awarded to small businesses through the program. Counterfactual simulations indicate that if participation were instead inelastic to bid preferences, the 5-percent bid preference would be close to the optimal level.
Estimation of SCRAM Rate Trends in Nuclear Power Plants Using Hierarchical Bayes Models

Nuclear reactors are equipped with reactor scram systems to ensure rapid shutdown of the system in the event of leaks, failure of power conversion systems, or other operational abnormalities. The U.S. Nuclear Regulatory Commission (NRC) collects data on scram rates from various nuclear power plants over time to estimate the trend of proper functioning of the plants which in turn is used to regulate them. The annual scram data obtained from 66 commercial nuclear power plants indicate an increase in the number of plants having no scrams from 1.5% in 1986 to 33% in 1993. To analyze correlated count data with excess zeros (e.g., no scrams), a zero-inflated model that accounts for both temporal and plant-to-plant variation is being developed in this article. A wide class of possibly non-nested models was fitted using Markov Chain Monte Carlo (MCMC) methods and compared using a predictive criterion. Out-of-sample tests were also performed to study the performance of the models in predicting the scram rates of t...
Contemporary Use of and Future Roles for Heparin in Antithrombotic Therapy

Although heparin therapy is an established component of the prevention and treatment of thromboembolic disease, recent advances have resulted in improvements in the clinical use of this agent. Studies have shown that weight-based dosing influences significantly both the time to reach a therapeutic intensity of anticoagulation and the incidence of thromboembolic recurrence. It is now considered the standard of care. A growing understanding of the variability among activated partial thromboplastin time (aPTT) reagents and the influence of these differences on aPTT outcomes has led to the use of reagent-specific therapeutic ranges for heparin monitoring. Many practitioners now choose to adjust the therapeutic range to correspond to heparin serum concentrations of 0.2-0.4 U/mL rather than the more common practice of prolonging aPTT to 1.5-2.5 times the mean normal aPTT. Pharmaceutical companies have developed low molecular weight heparins to minimize adverse effects associated with unfractionated heparin. More specific thrombin inhibitors are also under investigation with the aim of improving clinical outcomes in coronary syndromes now treated with heparin. Low molecular weight heparins or specific thrombin inhibitors are unlikely to replace unfractionated heparin in the near future. Therefore, optimum dosing and appropriate monitoring of heparin are critically important in the management of thromboembolic disease.
Frequency response of gas mixing in a fluidized-bed reactor

Frequency response methods were used to compare dynamic models for gas mixing and first-order reaction in a fluidized-bed reactor and for the experimental determination of interphase transfer characteristics. Theoretical predictions of frequency response characteristics were derived for two models based on the two-phase theory of fluidization. Experimental frequency response for a 1-ft. high bed were correlated better by a model based on perfect mixing in the dense phase than by a model based on plug flow in the dense phase. Excellent correlation was also obtained by a simple empirical model.
Kepler, elliptical orbits, and celestial circularity: A study in the persistece of metaphysical commitment: Part II

Summary The metaphysical commitment to the circle as the essential element in the analysis of celestial motion has long been recognized as the hallmark of classical astronomy. What has not always been clear, however, is that the circle continued to serve Kepler as a central element in his astronomy after the discovery of the elliptical orbit of Mars. Moreover, the circle also functioned for Kepler in geometry to select the basic polygons, in music to select the basic harmonies, and in astrology to select the basic aspects. His basic set of polygons consisted of those figures that could be constructed using only a compass and a rule; the set of fundamental harmonies consisted of the consonances of the just intonation; and the traditional set of astrological aspects were enlarged by Kepler to include three new aspects in order to make the astrological set consistent with geometry and music. And as the circle served to unify these three areas, so also did it serve to supply the fundamental answers to astrono...
Activation of rat hepatic stellate cells leads to loss of glutathione S-transferases and their enzymatic activity against products of oxidative stress.

Oxidative stress, mediated partly by lipid peroxidation products, may lead to increased collagen synthesis by hepatic stellate cells (HSC). Stellate cells are protected from oxidative stress by enzymes of detoxication such as the glutathioneS-transferases (GSTs), which form glutathione conjugates with lipid peroxidation products (e.g., 4-hydroxy-2-nonenal [HNE]). To better understand the role of GSTs in stellate cell biology, we examined the expression and enzymatic activity of GSTs in normal and activated (both culture- and in vivo–activated) stellate cells. Normal stellate cells contained numerous isoforms of GST including those that detoxify HNE. High levels of enzymatic activity toward 1-chloro-2,4-dinitrobenzene (CDNB) and HNE were present in normal stellate cells and were similar to levels present in whole liver. Following activation by growth in culture, the expression of several GSTs (rGSTA1/A2, A3, and M1) was lost. Also, enzymatic activities toward CDNB and HNE fell ∼90%. However, expression of rGSTP1 was maintained. A similar loss of rGSTA1/A2, A3, and M1 with persistent expression of rGSTP1 was present after activation in vivo. Furthermore, we identified 2 subpopulations of activated stellate cells with different GST phenotypes from injured livers. In summary, activated stellate cells lose most forms of GST and associated enzymatic activities that are present in normal stellate cells. The findings raise the possibility that activated stellate cells have less ability to detoxify lipid peroxidation products and may be susceptible to oxidative stress. Additionally, we propose that the phenotypic change in GSTs is a sensitive marker of stellate cell activation.