cssi/SciSciGPT-SciSciNet huggingface dataset:
α-Synuclein overexpression enhances manganese-induced neurotoxicity through the NF-κB-mediated pathway

Exposure to manganese (Mn) occurs in both civilian and military operations. Mn exposure results in a movement disorder termed manganism, which resembles Parkinson's disease (PD). However, the pathogenic mechanisms underlying this disorder are not fully understood. α-Synuclein, a presynaptic protein is implicated in some neurodegenerative disorders, including PD and Mn-induced apoptosis, and its overexpression contributes to the loss of dopaminergic neurons. Although the role of α-synuclein in this process is widely documented, its exact function is not clear. The objective of this study was to evaluate the mechanism(s) of dopaminergic degeneration associated with α-synuclein expression in response to Mn exposure and to assess the role of nuclear factor-κB (NF-κB) activation as an intermediary of Mn-induced neurotoxicity. Rat mesencephalic cells (MES 23.5) overexpressing human α-synuclein show enhanced susceptibility to Mn exposure as evidenced by increased apoptosis and NF-κB nuclear translocation. Pretreatment with antioxidants and the p38 mitogen-activated protein kinase (MAPK) inhibitor SB239063 significantly diminished NF-κB activation, supporting a role for oxidative stress and p38 MAPK in Mn-induced NF-κB activation. In addition, increased nitric oxide generation was evident during NF-κB activation, which was blocked by NF-κB (SN50) and MAPK inhibitors. Mn-induced cell death was attenuated by SN-50 and specific nitric oxide synthase (NOS) inhibitor (1400W); corroborating NOS activation is mediated through NF-κB in the mechanism of cell death. These data indicate that the transcription factor NF-κB, p38 MAPK, and apoptotic signaling cascades are activated by Mn in human α-synuclein-overexpressing cells. Thus, α-synuclein may facilitate Mn-induced neurotoxicity, and along with NF-κB, it may play a role in dopaminergic cell death.
Acceptor pincer Ru(II) chemistry.

A series of new acceptor pincer Ru(II) complexes are reported. The carbonyl complex (CF3PCP)Ru(CO)Cl2−Et3NH+ is obtained from the reaction of CF3PCPH with [(cod)Ru(μ-Cl)2]n. Chloride displacement with CF3PCPH, CO, PPh3, or C2H4 gave complexes of the type (CF3PCP)Ru(CO)(L)Cl, or in the case of CF3PCPH, the bridged dimeric complex [(CF3PCP)Ru(CO)Cl]2(μ-CF3PCPH). Chloride abstraction from (CF3PCP)Ru(CO)(L)Cl, L = CO or PPh3 by (Et3Si)2(μ-H)+B(C6F5)4− followed by Et3N addition produced (CF3PCP)Ru(CO)(L)(H) products. Reaction of cis-(CF3PCP)Ru(CO)2Cl with (Et3Si)2(μ-H)+B(C6F5)4− in the presence of excess CO afforded (CF3PCP)Ru(CO)3+. The reaction of CF3PCPH with (PPh3)3Ru(H)(O2CR) (R = Me or Ph) produced the corresponding carboxylate complexes (CF3PCP)Ru(PPh3)(O2CR).
Using an architectural knowledge base to generate code for parallel computers

Code generation for existing parallel computers involves partitioning the work into schedulable units, assigning the resulting computational units to specific processors, and generating the code for interprocessor communication and synchronization. The options for partitioning and mapping depend in detail on the problem being solved and the algorithm and architecture being used. For each new combination of problem, algorithm, and architecture, a new partitioning and mapping must be created and evaluated based on the actual communication costs incurred. If a particular choice of partition and map is found to be too inefficient when the communication cost is analyzed, it is usually necessary to repeat the code generation process from the beginning.Given the complexity of this problem, it is not practical to develop a general algorithmic approach. A more promising approach is to develop restricted code generation strategies which are suitable for a class of problems and architectures, and compilers which use heuristic advice to guide code generation.In this paper we present a compiler for distributed memory parallel computers which perform automatic program partitioning, mapping and communication code generation under the guidance of a strategy rule-base. All partitioning and mapping is performed automatically, and communication primitives are generated. We describe the compiler system and present an example code generation strategy for iterative elliptic partial differential equation solvers.
AMOUNT OF DREAMING: EFFECT OF INCENTIVE, ADAPTATION TO LABORATORY, AND INDIVIDUAL DIFFERENCES.

The relationships between several variables and amount of dreaming, defined as time spent in the rapid eye movement stage of sleep, were investigated. Twenty Ss slept in the laboratory for four nights each in accord with a counterbalanced design. Monetary incentive to control amount of dreaming had a small but significant effect on amount of dreaming. On the first experimental night, Ss dreamed less than on succeeding nights; this decrease in dreaming was associated with more spontaneous awakenings on the first night than on succeeding nights. There were stable individual differences in amount of dreaming. The longer the sleep period prior to the first dream of the night, the longer was the first dream.
Mechanisms of Myocardial Capture and Temporal Excitable Gap During Spiral Wave Reentry in a Bidomain Model

Background— Recent studies have demonstrated that regional capture during cardiac fibrillation is associated with an elevated capture threshold. It is typically assumed that the temporal excitable gap (capture window) during fibrillation reflects the size of the spatial excitable gap (excitable tissue between fibrillation waves). Because capture threshold is high, virtual electrode polarization is expected to be involved in the process. However, little is known about the underlying mechanisms of myocardial capture during fibrillation. Methods and Results— To clarify these issues, we conducted altogether 3168 simulations of single spiral wave capture in a bidomain sheet. Unipolar stimuli of strengths 4, 8, 16, and 24 mA and 2-ms duration were delivered at 99 locations in the sheet. We found that cathode-break rather than cathode-make excitation was the dominant mechanism of myocardial capture. When the stimulation site was located diagonally with respect to the core (upper left or lower right if the spiral...
The NAEP Geography Report 2010: What Will We Do Next?

The National Assessment of Educational Progress (NAEP) rightly calls itself the Nation's Report Card. As the gold standard of educational assessment, it offers a picture of what U.S. students know ...
Survival and reproduction of the cat flea (Siphonaptera: Pulicidae) fed human blood on an artificial membrane system.

Adult cat fleas, Ctenocephalides felis (Bouche), survive and reproduce when fed human blood through an artificial membrane system. When a dog hair substrate was included in cages with the fleas, mean adult mortality was 2.4 after 12 d of bloodfeeding. Egg production began after 3 d and was continuous for 12 d, ranging from 3 to 4 eggs per female per day. In cages without hair, mean adult mortality was 61.2% after 12 d of bloodfeeding. Egg production began after 2 d, reached a maximum of two eggs per female per day after 7 d, and decreased thereafter. No significant differences in egg hatch were seen in treatment groups sampled from 5 to 7 d after the onset of bloodfeeding. After 7 d, however, egg hatch for fleas maintained in cages without hair was significantly lower than in cages where fleas were maintained on dog hair. Adult emergence from these larvae did not differ significantly between the two groups. Egg hatch and adult emergence in both groups of fleas fed on human blood did not differ significantly from egg hatch and adult emergence in fleas fed on colony cats.
Effects of Oil Spills on Terrestrial Arthropods in Coastal Wetlands

Coastal wetlands are important to human well-being and vulnerable to oil spills. Research on biotic effects of oil has been focused on microbes, plants, and benthic invertebrates, neglecting terrestrial arthropods. We review how oil affects terrestrial arthropods in coastal marshes and suggest future research topics. Terrestrial arthropods play important ecological roles in coastal marshes, affecting primary production and decomposition and providing food to terrestrial and marine vertebrates. Some species are pests and disease vectors for humans and livestock. Terrestrial arthropods are sensitive to oil exposure and are suppressed even in lightly oiled sites where plants are not affected. Some arthropods later reinhabit oiled marshes, which demonstrates that portions of the arthropod community may be resilient to oil exposure. However, oil that remains in sediments may affect terrestrial populations for years after the spill. The sensitivity of arthropods to oil exposure makes them useful indicators of marsh health following environmental impacts.
LinkedVis: exploring social and semantic career recommendations

This paper presents LinkedVis, an interactive visual recommender system that combines social and semantic knowledge to produce career recommendations based on the LinkedIn API. A collaborative (social) approach is employed to identify professionals with similar career paths and produce personalized recommendations of both companies and roles. To unify semantically identical but lexically distinct entities and arrive at better user models, we employ lightweight natural language processing and entity resolution using semantic information from a variety of end-points on the web. Elements from the underlying recommendation algorithm are exposed through an interactive interface that allows users to manipulate different aspects of the algorithm and the data it operates on, allowing users to explore a variety of "what-if" scenarios around their current profile. We evaluate LinkedVis through leave-one-out accuracy and diversity experiments on a data corpus collected from 47 users and their LinkedIn connections, as well as through a supervised study of 27 users exploring their own profile and recommendations interactively. Results show that our approach outperforms a benchmark recommendation algorithm without semantic resolution in terms of accuracy and diversity, and that the ability to tweak recommendations interactively by adjusting profile item and social connection weights further improves predictive accuracy. Questionnaires on the user experience with the explanatory and interactive aspects of the application reveal very high user acceptance and satisfaction.
The Effect of Information on Consensus and Accuracy in Personality Judgment

Abstract An experimental study examined the effect of the amount of available information on interjudge consensus and self–other agreement (accuracy) in personality judgment. Three hundred sixty perceiver-subjects (180 F and 180 M) each watched one of 6 targets (3 F and 3 M) on videotape for 5–10, 15–20, or 25–30 min. Accuracy was significantly greater in the longest than in the shortest observation condition. Within this overall difference, the linear effect of information on accuracy was strong (and significant) only for the most visible of the traits that were judged, including those relevant to extraversion. A fairly high level of consensus was achieved after the shortest period of observation and did not increase with longer observation for any kind of trait. Among a separate group of acquaintances who had known the targets for an average of 14 months, both accuracy and consensus was much higher than our perceiver-subjects achieved after 30 min. Further analyses showed that, with more information, consensus was more highly associated with accuracy, even though the level of consensus did not change.
Biosensing platform on a flexible substrate

Abstract The work presents implementing a low cost pH sensing system for biological applications in a flexible electronics process. As a part of the system the work describes an ion sensitive field effect transistor, using indium tin oxide (ITO) as a sensing layer and gold as a reference electrode, on a flexible substrate. The devices presented here are designed and fabricated using the thin film transistor (TFT) display technology at the Arizona State University Flexible Electronics and Display Center. It was observed that ITO has a sensitivity of 50 mV/pH. The work also discusses the variability in these devices and signal processing that could be used to calibrate them. Toward this end, a readout circuit designed in a 0.5 μm CMOS process is presented to interface with the sensors.
420 ENHANCED JEJUNAL MACROMOLECULAR ABSORPTION INDUCED BY SECONDARY BILE SALTS

This study concerns the deleterious effects of secondary bile salts, tauro-deoxycholate (TDCh)and deoxycholate (DCh), particularly on small intestinal macromolecular absorption. Rat jejunal segments (30-40 cm)were perfused in vivo with an isotonic NaCl-glucose solution (pH6.9)containing 0.5 g% of horseradish peroxidase (HRP)a macromolecular tracer,with 5mM TDCh or DCh or without bile salts (C). After 30 and 60 min serum HRP levels and cytochemical HRP localization were determined. Both TDCh and DCh induced a greater absorption of HRP than C: at 30 min TDCh .157± .005, DCh .439 ±.080 vs C .082 ± .010, and at 60 min TDCh .381 ± .061, DCh 1.001 ± .138 vs C .114 ± .011 (data=u/ml means ± SEM, p<.001). The most striking absorption of HRP was with DCh. Under light and electron microscopy HRP was demonstrable in the intercellular spaces between enterocytes, in the basement membranes, and capillaries of the lamina propria of the jejunum. In contrast, in C, HRP was confined to the microvillar brush border and endocytotic structures of enterocytes. DCh also produced ultrastructural damage including swollen mitochondria and vacuolization of membrane systems whereas TDCh did not alter the intestinal epithelium. These results indicate that high concentrations of secondary bile salts enhance macromolecular absorption and induce functional damage to the jejunal epithelium. Deconjugated bile salts are the most injurious.
Fluorescence excitation spectra and light utilization in two red tide dinoflagellates

We compared the impact of structural changes in the light-harvesting machinery of two bloom-forming dinoflagellates (Prorocentrum minimum and Heterocapsa pygmaea) by quantifying photophysiological changes in order to define the alternative mechanisms of photoacclimation. There are species-specific and photoacclimative differences in the abundance and composition of functional light-harvesting complexes (including photosystem 1- and 2-enriched bands) which are reflected in spectral changes in absorption, and photosystem 2 (PS2) fluorescence excitation spectra of whole cells, thylakoid micelles, and discrete photosynthetic pigment-protein complexes. DCMU-induced variations in fluorescence excitation spectra are evident in whole cells but not in isolated thylakoid micelles or functional chromoproteins; such variations indicate that intracellular self-shading which causes variable fluorescence is eliminated in subcellular preparations. We developed a scaling procedure of PS2-related in vivo fluorescence excitation spectra relative to Chl a-specific absorption coefficients and used the chromoprotein differences to illustrate how the chromoprotein composition alters cellular fluorescence properties. We also examined the energy transfer efficiency of photosynthetic pigments and the photoprotective role and location of diadinoxanthin.
Pythia 8: Simulating Tau-Lepton Decays

Abstract As of version 8.150 of Pythia , the isotropic decays of τ-leptons have been replaced with a decay machinery that incorporates full spin correlations and more sophisticated decay models. Developments of the Pythia τ-lepton decay machinery from version 8.150 up to version 8.201 are summarized. The τ-lepton decay machinery in Pythia 8 is described, including the spin correlation algorithm, the available τ-lepton decay models, and the user interface.
Improvement in Patient Performance of Skin Self-examinations After Intervention With Interactive Education and Telecommunication Reminders: A Randomized Controlled Study.

OBJECTIVE To determine if interactive computerized patient education, skin self-examination (SSE) tutorials, and telecommunication reminders could be combined to increase patient performance of SSEs, increase confidence in ability to identify melanoma, and influence individual melanoma risk perception. DESIGN A total of 132 adult participants from our dermatology clinics were enrolled in an interventional study and randomized to a control group or an intervention group. Survey data were collected from all participants on the day of enrollment and 3 months after enrollment. SETTING University Hospitals Case Medical Center outpatient dermatology clinics. PARTICIPANTS English speakers older than 18 years. INTERVENTIONS The intervention group (1) participated in a computer-assisted learning tutorial, (2) took part in a hands-on SSE tutorial, (3) received monthly telecommunication reminders to perform SSEs for 12 weeks, and (4) received a brochure on melanoma detection. The control group received only the brochure on melanoma detection. MAIN OUTCOME MEASURES Self-report of performance of SSEs. Melanoma risk perception and confidence in ability to identify melanoma were secondary considerations. Logistic regressions, controlling for race, age, sex, education, and family history of melanoma, were used to assess the effectiveness of the intervention. RESULTS At the 3-month follow-up, those in the intervention group were more likely to perform SSEs (odds ratio [OR], 2.36; P ≤ .05). In addition, those who participated in the intervention were more likely to report being confident in their ability to identify melanoma during an SSE (OR, 2.72; P ≤ .05). CONCLUSION Computer-assisted patient education used in conjunction with a hands-on SSE tutorial and telecommunication reminders can increase patient performance of SSEs and confidence in the ability to identify melanoma.
Use of dynamic influence coefficients in forced vibration problems with the aid of fast fourier transform

Abstract The use and importance of dynamic stiffness influence coefficients in flexural forced vibrations of structures composed of beams are described. The dynamic forces can be either harmonic or general transient forces. The dynamic influence coefficients are defined in the Fourier transform plane, are computed there and are given in Table form for a uniform free-free beam. The dynamic problem formulated in terms of these coefficients is reduced to a static form. The dynamic response is obtained, in general, by a matrix inversion in the Fourier transform plane and a numerical inversion, based on the Cooley-Tukey algorithm, of the transformed solution. Structural examples of forced vibrations of a simple beam and a rigid frame illustrate the use of dynamic coefficients and demonstrate their advantages over other known methods in accuracy, simplicity of formulation and speed of computation.
EFFECTS OF VENOM FROM THE SCORPION, CENTRUROIDES SCULPTURATUS ON THE RAT.

Abstract Anesthetized rats treated with intravenous injections of Centruroides sculpturatus venom developed hypotension, bradycardia and respiratory irregularities. These responses contrast with those reported elsewhere for dogs and cats. The anesthetic used, sodium pentobarbital, had no effect on the LD 50 of this venom. Also, this venom proved to be active at lower concentrations in rats than in cats.
Porous ion emitters—A new type of thermal ion emitter

Abstract A new type of porous refractory material has been developed as a thermal ionization emitter that is an improvement over both direct filament and resin bead loading. The porous ion emitter is sintered onto the center of a conventional thermal ionization filament and an aqueous solution containing the sample wicked into this emitter. Application of the porous ion emitter to uranium is demonstrated to provide a utilization efficiency ranging between 1% and 2% across a sample size range of 0.2–10 pg, better than that achieved from resin beads and much better than that achieved with direct loading onto a filament. The technique improves sensitivity and reduces the chance of losing a high value sample when manipulating a single resin bead containing an entire sample.
How Is Meaning Grounded in the Organism

In this paper we address the interrelated questions of why and how certain features of an organism’s environment become meaningful to it. We make the case that knowing the biology is essential to understanding the foundation of meaning-making in organisms. We employ Miguel Nicolelis et al’s seminal research on the mammalian somatosensory system to enrich our own concept of brain-objects as the neurobiological intermediary between the environment and the consequent organismic behavior. In the final section, we explain how brain-objects advance the ongoing discussion of what constitutes a biosemiotic system. In general, this paper acknowledges Marcello Barbieri’s call for biology to make room for meaning, and makes a contribution to that end.
Size effects in shape memory alloy microwires

Abstract In shape memory alloys, the reversible phase transformations between austenite and martensite give rise to superelasticity and shape memory properties. Here we systematically study the sample size dependence of these properties and the associated transformations in polycrystalline shape memory alloy microwires with a bamboo grain structure, i.e. where the wire diameter is completely spanned by individual grains. Cu–Al–Ni wires with diameters ranging from ∼500 down to ∼20 μm are fabricated by the Taylor liquid processing technique, and are characterized by both isothermal uniaxial tensile testing and mechanically constrained thermal cycling. We observe size effects in both the transformation stresses and temperatures. What is more, we find that the stress hysteresis in a mechanical cycle and the temperature hysteresis in a thermal cycle both increase with decreasing wire diameter, particularly for wires smaller than 100 μm. A direct consequence of the increased hysteresis is enhanced energy dissipation (i.e. damping capacity) in smaller wires. We also discuss possible physical origins of the observed size effects, including interface and surface energies, stored elastic energy, heat transfer and internal friction.
The Aesthetics of the Invisible: Sacred Music in Secular (French) Places

Is listening a performance? How do “invisible” practices like Sufi Muslim sama', or sacred listening, impact the public and secular spaces of contemporary France? What do listening acts reveal about the political viability and performativity of sacred listening in a secular nation?
TOXICITY OF DISPERSED AND UNDISPERSED PRUDHOE BAY CRUDE OIL FRACTIONS TO SHRIMP AND FISH

ABSTRACT Many previous studies of oil toxicity used high oil concentrations and water soluble fractions (WSF). The aim of this study was to approximate field conditions, in which weathering and chemical dispersions reduce the volatile fractions of spilled crude oil. The objective was to determine the extent of toxicity reduction produced by decreased concentrations of monoaromatics and diaromatics. The study measured the relative toxicity of fresh Prudhoe Bay crude (PBC) oil and two distillation fractions (Stage I and Stage II) and their chemical dispersions to the shrimp Pandalus danae and the fish Ammodytes hexapterus (sand lance). The hydrocarbon composition of the three oils, the WSF of the oils, and the chemical dispersions were measured. Distillation of fresh PBC oil produced a Stage I oil containing very low amounts of monoaromatics (benzene and alkylbenzenes) but with the diaromatics relatively unchanged. Further distillation produced a Stage II oil which contained only higher molecular weight aro...
N-RAS oncogene mutations in patients with agnogenic myeloid metaplasia in leukemic transformation

Abstract From 5% to 20% of patients with agnogenic myeloid metaplasia (AMM) will evolve into a terminal leukemic phase; N-RAS gene mutations are the most common gene abnormalities detected in patients with leukemia. The present study was designed to see if N-RAS gene mutations are associated with the leukemic transformation in AMM. Over a 9 year period, in a single institution, 43 patients with AMM were studied. Of these, ten patients were found to be in leukemic phase. The results showed that none of the patients in chronic phase (40 patients) had N-RAS gene mutations, while two patients in leukemic phase showed this gene mutation. One patient was found to have a codon 12 mutation with arginine substituting for glycine (GGT→CGT); the other was a codon 12 mutation with glutamine substituting for glycine (GGT→GAT). The present study suggests that N-RAS mutations are rare events in the chronic phase of AMM, and are only occasionally found when patients have evolved into leukemic transformation. Further studies to search for other gene abnormalities in AMM may be warranted.
Near-real-time modal reconstruction using frequency-domain C 2 imaging

We demonstrate frequency-domain cross-correlated (C2) imaging to reconstruct fiber modes and measure relative weights. Measurements take only 1.5 s, yield sub-ps group delay resolution and 25 dB modal discrimination, facilitating near-real-time monitoring of modal purity.
The interaction of atrazine with wetland sorbents

Abstract Atrazine equilibrium sorption data for sediments, litter, peat, root mat, and soil from three Midwestern USA wetlands fit the Freundlich isotherm model, Cs = K Cwn. Water atrazine concentrations were in the μg/dm3 range. Sorbent analyses recovered most of the atrazine not found in the water. Data errors in sorbent atrazine concentrations were much larger than those in water concentrations. Maximum likelihood and logarithmic regression methods gave similar parameter estimates. Organic carbon (OC) based sorbent concentrations allowed combination of the data into one isotherm. Estimates for KOC and n were 760 (μg/kg OC)(μg/dm3)−n and 0.90. A linear isotherm null hypothesis was rejected. Fresh sorbents containing identifiable plant fragments had significantly lower KOC values than aged ones that did not. Atrazine reaction affected KOC estimation for fresh sorbents, but not for aged ones. Litter had an unexpectedly high weight based K value. KOC estimates were higher than comparable literature values, mainly for soils at mg/dm3 concentrations. Drying materials before equilibration may lead to underestimation of sorption capacity of active, wet organic matter. Wetlands have capacity to sorb significant amounts of atrazine onto sediments, litter, and root mats. However, short detention times may prevent full realization of this potential.
Role of the Recombinant Protein of the Platelet Receptor for Type I Collagen in the Release of Nitric Oxide During Platelet Aggregation

Nitric oxide plays an important role in platelet function and platelets possess the endothelial isoform of nitric oxide synthase. Several reports have indicated that nitric oxide is released upon exposure of platelets to collagen. We have reported that a non-integrin platelet protein of 65 kDa is a receptor for type I collagen. By direct measurement of NO release from washed human platelets suspended in Tyrode buffer with a ISO-NO Mark II, World Precision Instruments, Sarasota, FL, USA, p30 sensor, type I collagen, but not ADP and epinephrine, induces the release of NO in a time-dependent manner. The production of NO is inhibited either by preincubation of type I collagen with the platelet type I collagen receptor recombinant protein or by preincubation of platelets with the antibody to the receptor protein, the anti-65 antibody. However, preincubation of platelets with anti-P-selectin and anti-glycoprotein IIb/IIIa did not affect the release of NO by platelets. These results suggest that the 65 kDa platelet receptor for type I collagen is specifically linked to the generation of NO, and that the 65 kDa platelet receptor for type I collagen plays an important new role in platelet function.
Adding more observations to saturated D-optimal resolution III two-level factorial designs

We consider the class of saturated main effect plans for the 2k factorial. With these saturated designs, the overall mean and all main effects can be unbiasedly estimated provided that there are no interactions. However, there is no way to estimate the error variance with such designs. Because of this and other reasons, we like to add some additional runs to the set of (k+1) runs in the D-optimal design in this class. Our goals here are: (1) to search for s additional runs so that the resulting design based on (k+s+1) runs yields a D-optimal design in the class of augmented designs; (2) to classify all the runs into equivalent classes so that the runs in the same equivalent class give us the same value of the determinant of the information matrix. This allows us to trade runs for runs if this becomes necessary; (3) to obtain upper bounds for determinant of the information matrices of augmented designs. In this article we shall address these approaches and present some new results. © 2002 Wiley Periodicals, Inc. J Combin Designs 11: 51–77, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jcd.10026
Mechanism of HTO formation in gaseous tritium mixtures

The mechanisms for the conversion of molecular tritium gas to tritiated water are examined for tritium mixtures with (1) oxygen and nitrogen, (2) oxygen and argon, and (3) water and helium, for which previous experimental data exist. By analyzing results of these experiments in light of the radiation chemistry involved in a mixture of tritium and other gases, an understanding of the conversion mechanisms is reached. The formation of H and/or OH free radicals as intermediate species is of particular significance in the formation of HTO in that these radicals initiate a number of reactions which lead to the formation of water. These reactions are analyzed in terms of steady-state kinetics to obtain predictive models which can be judged against the experimental observations. For the three experimentally observed mixtures, model agreement is found to be within a factor of 2–3.
Activated expression of cardiac adenylyl cyclase 6 reduces dilation and dysfunction of the pressure-overloaded heart

Abstract Background and objective Cardiac-directed adenylyl cyclase 6 (AC6) expression attenuates left ventricular (LV) hypertrophy and dysfunction in cardiomyopathy, but its effects in the pressure-overloaded heart are unknown. Methods Mice with cardiac-directed and regulated expression of AC6 underwent transaortic constriction (TAC) to induce LV pressure overload. Ten days prior to TAC, and for the duration of the 4 week study, cardiac myocyte AC6 expression was activated in one group (AC-On) but not the other (AC-Off). Multiple measures of LV systolic and diastolic function were obtained 4 week after TAC, and LV samples assessed for alterations in Ca2+ signaling. Results LV contractility, as reflected in the end-systolic pressure–volume relationship (Emax), was increased (p = 0.01) by activation of AC6 expression. In addition, diastolic function was improved (p Conclusions Activation of cardiac AC6 expression improves function of the pressure-overloaded and failing heart. The predominant mechanism for this favorable adaptation is improved Ca2+ handling, a consequence of increased PLN phosphorylation, reduced NCX1, reduced PP1 expression, and increased SR Ca2+ content.
Oxidative Stress and Vascular Disease: 2005 Duff Lecture

There is compelling evidence that oxidative stress plays a key role in the pathophysiology of several major cardiovascular diseases. In atherosclerosis, hypertension, stroke, diabetes, and heart failure, expression of superoxide is increased in blood vessels, and endothelial vasomotor function is impaired, presumably caused in large part by inactivation of nitric oxide by superoxide. Endothelial dysfunction is predictive of cardiovascular risk, and probably plays a key role in the pathophysiology of atherosclerosis and its complications. In preliminary studies in hypercholesterolemic mice and in older humans, we have found high levels of superoxide in the aortic valve, as well as aorta. We speculate that superoxide, in addition to playing a key role in atherogenesis, may play a key role in signaling that leads to calcific aortic valvular stenosis. Antioxidant enzymes, especially the three isoforms of superoxide dismutase (SOD), modulate basal levels of superoxide and protect against vasomotor dysfunction. A common gene variant of extracellular SOD (ecSOD) is associated with increased risk of ischemic heart disease. We have made recombinant adenoviruses to examine cardiovascular effects of ecSOD and its heparin-binding domain. This approach might be used to study the almost 500 other proteins with a heparin-binding domain. Finally, several key unanswered questions in relation to oxidative stress and atherosclerosis are raised, and proposed as fruitful areas of research.
Drinking adolescents on the roads.

A social-learning model [R. C. Akers, M. D. Krohn, L. Lanza-Koduce, and M. Radosevich (1979), “Social Learning and Deviant Behavior: A Specific Test of a General Theory,”American Sociology Review, 44: 636–655] was tested for its ability to explain why adolescents drive under the influence of alcohol and ride with drinking drivers. Data were gathered from a survey of 1,082 high school students. Findings indicate that all five subsets of the model are significant determinants of adolescent driving under the influence and riding with drinking drivers. The study demonstrates that if adolescent drinking and driving is to be prevented, careful attention must be paid to ways that it is learned and maintained.
Correlation of DNA sequence specificity of anthramycin and tomaymycin with reaction kinetics and bending of DNA

Anthramycin and tomaymycin are potent antitumor antibiotics belonging to the pyrrolo[1,4]-benzodiazepine [P[1,4]B] group. Their potent biological effects are thought to be due to their ability to react with DNA within the minor groove, forming covalent adducts through the N2 of guanine with the drug molecules overlapping with a 3-4 bp region. In spite of their small molecular weights, the P[1,4]B's show a surprising degree of sequence selectivity, with 5'-PuGPu sequences being the most reactive and 5'-PyGPy sequences being the least reactive [Hertzberg, R. P., Hecht, S. M., Reynolds, V. L., Molineux, I. J., & Hurley, L. H. (1986) Biochemistry 25, 1249-1258]. It has been proposed that inherent DNA flexibility may be one important component of the sequence recognition process for P[1,4]B bonding to DNA, and in this regard, molecular modeling studies are reflective of the experimentally determined hierarchy of bonding sequences [Zakrzewska, K., & Pullman, B. (1986) Biomol. Struct. Dyn. 4, 127-136]. In this study, we have used chemical and enzymatic probes (hydroxyl radical, DNase I) to evaluate drug- and sequence-dependent changes in DNA-adduct conformation, gel electrophoresis to measure drug-induced bending in DNA, and HPLC to measure the reaction kinetics of anthramycin bonding to different sequences. The results show that tomaymycin bonding to DNA induces greater conformational changes in the DNA (i.e., bending and associated narrowing of the minor groove) than anthramycin. In addition, we find that within each drug species (i.e., tomaymycin or anthramycin), sequence specificity correlates with the degree of bending and reaction kinetics such that those sequences with the highest sequence selectivity produce more bending of DNA and react faster with DNA and vice versa. On the basis of these results, we propose that sequence-dependent conformational flexibility may be an important factor in determining the hierarchy of bonding sequences for the P[1,4]B's.
SU-E-J-62: Comparison of Brainlab ExacTrac, AlignRT, and CBCT Positional Accuracy for SRS Set-Up on a TrueBeam STx.

Purpose: To compare the ability of Brainlab ExacTrac (Brainlab AG, Feldkirchen, Germany) x‐ray (XRAY), Brainlab infrared array (IR), cone beam CT(CBCT), and AlignRT (VisionRT Ltd., London, UK) to accurately measure patient displacement during stereotactic radiosurgery(SRS) on a Varian TrueBeam STx (Varian Inc, Palo Alto, CA). Methods and Materials: A CT scan was obtained for a custom skull phantom placed in a Brainlab frameless SRS immobilization system with the Brainlab CT localizer box attached. A generic plan was created in Brainlab iPlan and sent to Brainlab ExacTrac, to AlignRT, and to the TrueBeam. The skull phantom was set‐up on the TrueBeam and positioned to isocenter using XRAY. Next, CBCT and IR were acquired and evaluated to determine baseline positions for these methods. A new AlignRT reference surface was acquired as baseline. The phantom was then displaced 2 mm in the vertical, lateral, and longitudinal dimensions using the TrueBeam couch (the couch tolerance is 0.1 mm in each dimension). New XRAY, IR, CBCT, and AlignRT data was acquired in this position. Results: Initially, all methods found that the phantom was positioned with < 0.3 mm accuracy. After the shiftes, XRAY suggested shifts were 2.0, 2,1, 1.8 mm in the vertical, longitudinal, and lateral dimensions, respectively. The IR shifts were 1.7, 2.6, 2.1 mm. The CBCT shifts were 1.8, 1.8, 2.1 mm. The AlignRT shifts were 2.2, 1.6, 1.4 mm. Conclusion: The internal XRAY and CBCT methods produced slightly better agreement with the table shifts. The external IR and AlignRT methods were less accurate, but still gave agreement of <= 0.6 mm. Note, the AlignRT cameras did not produce a clean surface off of the phantom. Improved accuracy is expected from a skin surface. This is preliminary work, more extensive study is needed to evaluate these methods.
Accepting research as social intervention: Implications of a systemic epistemology

This essay is an attempt to illustrate an alternative conceptualization of what is considered “science.” The systemic epistemology introduced by Bateson and others is described as an equally viable complement to traditional epistemological orientations. The distinction between the two orientations is the recognition, within the systemic epistemology, of the interventive role of the observer. A specific model is introduced as providing a working method for conducting research within the systemic epistemology. This model is borrowed from the field of systemic family therapy where intervention in social systems is celebrated and accepted. This model, although clinical in orientation, offers useful guidelines for developing research programs which acknowledge social intervention.
Is Screening for Chronic Obstructive Pulmonary Disease Justified

Abstract Background. Many experts recommend spirometry to screen for chronic obstructive pulmonary disease (COPD) in asymptomatic patients; however, evidence for this recommendation has not been systematically reviewed. Methods. We examined whether screening spirometry meets standard criteria for effective screening. We performed structured searches of MEDLINE, followed by a selective search of the CITATION index, to locate randomized trials of interventions for asymptomatic patients with COPD. In regard to smoking cessation, we included all controlled trials of smoking cessation programs that used spirometry. We also included all studies that assessed the ability of spirometry to predict successful smoking cessation by comparing baseline lung function in smokers who subsequently quit versus those who did not. Results. With the exception of smoking cessation, all interventions for COPD have only been proven effective in symptomatic patients. Two studies found that multifaceted smoking cessation programs that included spirometry were efficacious. There was no effect in a third study that isolated the role of spirometry. Smokers with abnormal spirometric results are less likely than other smokers to quit over the ensuing year. Conclusions. There is no evidence that spirometry, as an isolated intervention, aids smoking cessation.
Decreased Dendritic Branching in Frontal, Motor and Limbic Cortex in Rett Syndrome Compared with Trisomy 21

The branching of dendrites of pyramidal neurons in premotor frontal, motor and limbic cortex have been identified by us using Golgi technique to be less in Rett Syndrome (RS) brains than in non-Rett control brains. Decreased dendritic branching per se is not pathognomonic of a particular condition and has been reported in numerous disorders associated with mental retardation. This study was designed to test whether the dendritic alterations in Rett Syndrome are the same or different from the alterations present in Down Syndrome (DS), 1 specific form of mental retardation. Sections from Brodmann's areas 6, 4, 20, 43, 28, and 17 of premotor frontal, motor cortex, inferior temporal gyrus, hippocampal formation and the striate cortex from 16 Rett brains, 9 non-Rett brains and 9 Down's brains were prepared for dendrite analysis using the rapid Golgi technique. Drawings of apical and basilar dendrites of pyramidal neurons from 2 cortical layers and Cal were submitted to Sholl analysis. The analyses of Rett brains were compared with the analyses of the Trisomy 21 brains using the repeated measures analysis of covariance, with age as a covariate. The studies demonstrate in our sample that basal dendrites of layer III and V of frontal, layer IV of subiculum, and layer V of motor cortex and apical dendrites of layer III of frontal cortex have a significantly reduced dendritic arborization in RS compared with Trisomy 21. This study suggests that the cortical distribution of the dendritic alterations is specific for Rett Syndrome, and that the premotor frontal, motor and subicular cortex are preferentially involved in the, as yet, undefined process which affects brain growth and function in RS.
Adsorption and reaction of nitric oxide and oxygen on Rh(111)

Adsorption of NO and O2 on Rh(111) has been studied by TPD and XPS. Both gases adsorb molecularly at 120 K. At low coverages (θNO < 0.3) NO dissociates completely upon heating to form N2 and O2 which have peak desorption temperatures at 710 and 1310 K., respectively. At higher NO coverages NO desorbs at 455 K and a new N2 state obeying first order kinetics appears at 470 K. At saturation, 55% of the adsorbed NO decomposes. Preadsorbed oxygen inhibits NO decomposition and produces new N2 and NO desorption states, both at 400 K. The saturation coverage of NO on Rh(111) is approximately 0.67 of the surface atom density. Oxygen on Rh(111) has two strongly bound states with peak temperatures of 840 and 1125 K with a saturation coverage ratio of 1:2. Desorption parameters for the 1125 peak vary strongly with coverage and, assuming second-order kinetics, yield an activation energy of 85 ± 5 kcalmol and a pre-exponential factor of 2.0 cm2 s−1 in the limit of zero coverage. A molecular state desorbing at 150 K and the 840 K state fill concurrently. The saturation coverage of atomic oxygen on Rh(111) is approximately 0.83 times the surface atom density. The behavior of NO on Rh and Pt low index planes is compared.
DSP controlled low-voltage high-current fast-transient Voltage Regulator Module

Future generation of microprocessors will require high performance Voltage Regulator Modules (VRMs) that produce tightly regulated low supply voltage with very small deviation window and able to respond very quickly to a large and continuous load transients at high output current while maintaining a high power density. On one hand, the current drawn from the VRM by the microprocessor is continuously changing since it depends at the current use of the microprocessor. On the other hand, High Frequency VRMs as any Power Electronics System is a complex combination of linear, nonlinear, and switching elements that is required to have fast dynamics. Moreover, this complex combination is also real-time system that needs to continuously and instantly monitor and respond to the load changes (the microprocessor). A high performance basic control loop is essential to follow up with such transients. Such controller design is usually complicated especially since it requires high knowledge of the converter and its behavior and accurate converter model that includes nonlinearities and parameters and components variations. DSP has many advantages over the analog circuits when it comes to applying high performance sophisticated control techniques such the simplicity in applying sophisticated control algorithms and modifying them via software revision, lower environmental and noise sensitivity, and less components count. In this paper, a DSP setup to be
Predictability of the glycerin test in the diagnosis of Ménière's disease.

The response of patients with suspected Meniere's disease to the glycerin test was reviewed in a prospective evaluation covering a 10 year period. Three hundred and eightly three patients with 495 suspect ears were tested and were classified as to hearing improvement 3 h post-orally administered glycerin. Two hundred twenty-five patients (265 ears) were diagnosed as Meniere's disease. Sixty-six percent of these ears showed significant hearing improvement by pure tone threshold and/or speech discrimination measurements with the glycerin test. The test protocol developed and revised at the University of Washington provides a differential diagnostic means of identifying endolymphatic hydrops which is a specific and practical test. It is easily available as a routine office procedure.
Electric field-induced transient birefringence and light scattering of synthetic liposomes.

The dynamics of electric field-induced transient birefringence Deltan(t) and light scattering (detected as turbidity) of 190 nm diameter unilamellar vesicles of dioleoylphosphatidylcholine are investigated as a function of applied field strength E, length of the square pulse Deltat, lipid concentration, mean hydrodynamic diameter , ionic strength, and temperature. Generally, induced birefringence exclusively is observed at low lipid concentration and below certain threshold values of E and Deltat, whereas concomitant induced turbidity appears at high lipid concentration and above thresholds values of E and Deltat. Turbidity is monitored through the change in transmitted intensity DeltaS parallel(t) and DeltaS perpendicular(t) of light polarized parallel and perpendicular to the applied field E. The field-induced structural changes are reflected in double-exponential forward relaxation and triple-exponential reverse relaxation of the positive birefringence, and in non-exponential relaxations of DeltaS parallel (t) and DeltaS perpendicular(t). Under the field, the associated physical events are interpreted as elongation of the spherical bilayer shells in the direction of E, linear chain formation (pearling) of the induced dipolar liposomes parallel to E, and partial fusion of adjoining vesicles within the chains. Under conditions where electroporation can be detected, pore opening succeeds the elongation of the vesicles. After termination of the field, the vesicles return to their original time average spherical shape, the oriented chains randomize and disintegrate, and the fused structures are converted either to unilamellar or multilamellar vesicles.
Prompt-gamma neutron activation analysis system design: Effects of D-T versus D-D neutron generator source selection

Prompt-gamma neutron activation (PGNA) analysis is used for the non-invasive measurement of human body composition. Advancements in portable, compact neutron generator design have made those devices attractive as neutron sources. Two distinct generators are available: D-D with 2.5 MeV and D-T with 14.2 MeV neutrons. To compare the performance of these two units in our present PGNA system, we performed Monte Carlo simulations (MCNP-5; Los Alamos National Laboratory) evaluating the nitrogen reactions produced in tissue-equivalent phantoms and the effects of background interference on the gamma-detectors. Monte Carlo response curves showed increased gamma production per unit dose when using the D-D generator, suggesting that it is the more suitable choice for smaller sized subjects. The increased penetration by higher energy neutrons produced by the D-T generator supports its utility when examining larger, especially obese, subjects. A clinical PGNA analysis design incorporating both neutron generator options may be the best choice for a system required to measure a wide range of subject phenotypes.