cssi/SciSciGPT-SciSciNet huggingface dataset:
Two Erdős problems on lacunary sequences: Chromatic number and Diophantine approximation

Let {n k } be an increasing lacunary sequence, that is, n k + 1 /n k > 1 + ϵ for some ϵ > 0. In 1987, P. Erdős asked for the chromatic number χ(G) of a graph G with vertex set ℤ, where two integers x, y ∈ ℤ are connected by an edge if and only if their difference |x − y| is in the sequence {n k }. Y. Katznelson found a connection to a Diophantine approximation problem (also due to Erdős): the existence of θ ∈ (0, 1) such that all the multiples n j θ are at a least distance δ(θ) > 0 from ℤ. Katznelson showed that χ(G) ≤ Cϵ −2 |log ϵ|. We apply the Lovasz local lemma to establish that δ(θ) > cϵ |log ϵ| −1 for some θ, which implies that χ(G) < Cϵ −1 |log ϵ|. This is sharp up to the logarithmic factor.
Laser propagation in a subcritical foam: Subgrid model

We present a subgrid model for laser propagation in a subcritical foam. Our model describes the expansion of laser-irradiated foam elements that are below the resolution of the simulation grid and predicts the plasma conditions that result from burning down the foam. Our model can be included as a module within a larger multiphysics code, and we have implemented it within the code pF3D, which is used for simulating a laser-plasma interaction. The model predicts a reduced propagation velocity for a laser through a subcritical foam compared to simulating that foam as a homogeneous gas. This is attributed to the laser energy that goes into burning down the foam microstructure. We compare our model against experimental data by simulating a 2 mg/cc SiO2 foam shot performed at the Janus laser facility at the Lawrence Livermore National Laboratory. pF3D simulations with the foam model predict hot ion temperatures. This leads to a reduction in the level of stimulated Brillouin scattering (SBS), bringing the simulated level of SBS into agreement with the data. Intensity fluctuations at the foam front due to laser speckles and refraction result in ion temperature fluctuations when the foam burns down. These drive long-lived electron density fluctuations on scales that are large compared to the pore size.
Shape reconstruction of planar flexible spacecraft structures using distributed sun sensors

Abstract Flexible planar spacecraft, such as solar sails, phased antenna arrays and space solar power satellites vary their shape in flight and also may not have a known shape after deployment. To allow applications where spacecraft shapes are measured to allow the closed-loop correction of flight or payload parameters, this paper presents a method for measuring shapes with miniature sun sensors embedded within the structure. Two algorithms to reconstruct the shape of the structure from the two local angles to the sun are presented; the first one is geometry-based, whereas the second one uses a finite element model of the structure. Both algorithms are validated on a 1.3 m × 0.25 m structure with 14 novel miniature sun sensors with an accuracy of 0 . 5 ∘ , developed for the present research. The structure was reconstructed to an accuracy better than one millimeter by both algorithms, after undergoing bending and torsional deformations. While the geometrically based algorithm is fast and accurate for small deformations, the finite element based algorithm performs better overall, especially for larger deformations.
Taking a Stand?: An Initial Assessment of the Social and Racial Effects of Recent Innovations in Self-Defense Laws

In 2004, borrowing from characteristics of its defense of home (“Castle Doctrine”) statute, the state of Florida substantially revamped its self-defense statute to remove the Common Law duty to retreat and effectively sanction the use of force, including deadly force, “anywhere [one] ha[s] a lawful right to be.” This first modern version of a so-called ”Stand Your Ground” (SYG) law resulted in significant changes to the charging and prosecution of those alleged to have committed violence against others. Since 2004, over two dozen U.S. states have revamped their self-defense statutes to incorporate some portion of Florida’s substantive and procedural SYG reforms. Adopting states, however, have enacted these law changes without significantly studying the real world impact of such reforms, especially in terms of their potentially racialized effects. In the wake of Florida’s very public trial of George Zimmerman for killing unarmed teen, Trayvon Martin, empirical studies seeking to explicate the workings of these statutes have begun to emerge. My project seeks to cull the available data and recent research to provide a quantitative and qualitative feedback loop to policy makers regarding the operation of these laws. In particular, my work seeks to explore whether SYG laws actually deter violent crime. Additionally, I interrogate the under-examined racialized consequences of laws authorizing increased uses of violence in a society where individual decisions and judicial determinations about the appropriate uses of force are often affected by negative identity stereotypes and unconscious bias.
'The White Establishment Is Now the Minority': White Identity, Discrimination, and Linked Fate in the United States

Current media narratives proclaim that the status of whites atop the political and social hierarchy in the United States is in flux. Experimental research has shown that exposing people to such messages affects their racial identification and makes them more conservative. The goals of this study are to (1) examine the prevalence of white racial identification, the perception that whites are discriminated against, and the sense that one’s own fate is tied to the fate of whites as a whole, (2) examine the social and demographic antecedents of these sentiments, and (3) assess their impact on political engagement and patriotism. I find that conservatism and neuroticism are the strongest and most consistent predictors of white identity, discrimination perceptions, and linked fate. Linked fate promotes political engagement, particularly with regard to discussing politics, whereas identifying as white diminishes engagement. Identifying as white, however, has the strongest impact on patriotism. Perceiving discrimination against whites is not as influential as the other sentiments under investigation. The implications of these findings given ongoing social and political trends are discussed.
Isolation of Typical Marine Bacteria by Dilution Culture: Growth, Maintenance, and Characteristics of Isolates under Laboratory Conditions

Marine bacteria in Resurrection Bay near Seward, Alaska, and in the central North Sea off the Dutch coast were cultured in filtered autoclaved seawater following dilution to extinction. The populations present before dilution varied from 0.11 × 109 to 1.07 × 109 cells per liter. The mean cell volume varied between 0.042 and 0.074 μm3, and the mean apparent DNA content of the cells ranged from 2.5 to 4.7 fg of DNA per cell. All three parameters were determined by high-resolution flow cytometry. All 37 strains that were obtained from very high dilutions of Resurrection Bay and North Sea samples represented facultatively oligotrophic bacteria. However, 15 of these isolates were eventually obtained from dilution cultures that could initially be cultured only on very low-nutrient media and that could initially not form visible colonies on any of the agar media tested, indicating that these cultures contained obligately oligotrophic bacteria. It was concluded that the cells in these 15 dilution cultures had adapted to growth under laboratory conditions after several months of nutrient deprivation prior to isolation. From the North Sea experiment, it was concluded that the contribution of facultative oligotrophs and eutrophs to the total population was less than 1% and that while more than half of the population behaved as obligately oligotrophic bacteria upon first cultivation in the dilution culture media, around 50% could not be cultured at all. During one of the Resurrection Bay experiments, 53% of the dilution cultures obtained from samples diluted more than 2.5 × 105 times consisted of such obligate oligotrophs. These cultures invariably harbored a small rod-shaped bacterium with a mean cell volume of 0.05 to 0.06 μm3 and an apparent DNA content of 1 to 1.5 fg per cell. This cell type had the dimensions of ultramicrobacteria. Isolates of these ultramicrobacterial cultures that were eventually obtained on relatively high-nutrient agar plates were, with respect to cell volume and apparent DNA content, identical to the cells in the initially obligately oligotrophic bacterial dilution culture. Determination of kinetic parameters from one of these small rod-shaped strains revealed a high specific affinity for the uptake of mixed amino acids (a°A, 1,860 liters/g of cells per h), but not for glucose or alanine as the sole source of carbon and energy (a°A, ± 200 liters/g of cells per h). The ultramicrobial strains obtained are potentially a very important part of picoplankton biomass in the areas investigated.
The Theory of Group Extensions

The object of extension theory is to show how a group can be constructed from a normal subgroup and its quotient group. In this subject concepts from homological algebra arise naturally and contribute greatly to our understanding of it. The necessary homological machinery, including the definitions of the (co)homology groups, is presented in 11.2.
Adoption Capacity and the Spread of Suicide Bombing

In “The Spread of Military Innovations,” Andrea Gilli and Mauro Gilli question the importance of organizational factors in explaining whether violent non-state actors decide to use suicide bombing. Instead, they argue that the strategic environment faced by groups generates tactical incentives that better explain who adopts suicide bombing. While they are right to point out that tactical incentives shape the choices made by groups (a perspective shared by adoption capacity theory, the argument they criticize), their argument is based on a misunderstanding of the way that adoption capacity theory functions in the case of suicide bombing. Reassessing their evidence shows that Gilli and Gilli’s results actually demonstrate the strong robustness of adoption capacity theory, showing how organizational factors significantly influenced whether violent non-state actors adopted suicide bombing between 1981-2007. It is only their alternative measure of organization size, one inappropriate for testing adoption capacity theory, that is not significant. This reassessment also reveals new insights about the overall relationship between organizational politics and military innovation for both state and non-state actors, including the conceptual risks involved when importing ideas from the business innovation literature, and the utility of accounting for both capacity and interests in future research.
Signalling by Steroid Receptors

First page of article Keywords: steroid receptor; oestrogen receptor α; oestrogen receptor β; αERKO mice; βERKO mice; ligand-dependent transcription factor; basal transcription machinery; coactivators; corepressor; phosphorylation; proteasome; breast cancer; oestrogen receptor variant; hormone resistance
Letter to the Editor: Response to Dr. Fomon's Letter to the Editor: Absorption of Iron Using a Nonisotopic Method to Estimate Body Storage Iron

Letter to the Editor: Response to Dr. Fomon's Letter to the Editor: Absorption of Iron Using a Nonisotopic Method to Estimate Body Storage Iron
The Role of Oxidative Stress in Parkinson’s Disease

Oxidative stress plays an important role in the degeneration of dopaminergic neurons in Parkinson's disease (PD). Disruptions in the physiologic maintenance of the redox potential in neurons interfere with several biological processes, ultimately leading to cell death. Evidence has been developed for oxidative and nitrative damage to key cellular components in the PD substantia nigra. A number of sources and mechanisms for the generation of reactive oxygen species (ROS) are recognized including the metabolism of dopamine itself, mitochondrial dysfunction, iron, neuroinflammatory cells, calcium, and aging. PD causing gene products including DJ-1, PINK1, parkin, alpha-synuclein and LRRK2 also impact in complex ways mitochondrial function leading to exacerbation of ROS generation and susceptibility to oxidative stress. Additionally, cellular homeostatic processes including the ubiquitin-proteasome system and mitophagy are impacted by oxidative stress. It is apparent that the interplay between these various mechanisms contributes to neurodegeneration in PD as a feed forward scenario where primary insults lead to oxidative stress, which damages key cellular pathogenetic proteins that in turn cause more ROS production. Animal models of PD have yielded some insights into the molecular pathways of neuronal degeneration and highlighted previously unknown mechanisms by which oxidative stress contributes to PD. However, therapeutic attempts to target the general state of oxidative stress in clinical trials have failed to demonstrate an impact on disease progression. Recent knowledge gained about the specific mechanisms related to PD gene products that modulate ROS production and the response of neurons to stress may provide targeted new approaches towards neuroprotection.
Amputation and ambulation in diabetic patients: Function is the goal

The role of amputation in limb salvage is often poorly defined because the surgeon and the patient often attempt to save all limbs at all costs. The difficulty lies in selecting limb salvage versus early amputation. For the sedentary patient, a poorly functional salvaged limb can provide him/her with a higher quality of life than he/she would have with an amputation. For the active patient, early major amputation may offer the best functional outcome. Our experience with diabetic limb salvage over the last 20 years was retrospectively reviewed and compared with the existing literature in an attempt to better understand the role of amputation versus limb salvage in patients with diabetes. In the process, surgical techniques that we believe optimize foot and leg amputations were reviewed. Utilizing a team approach, limb salvage can yield a 64% ambulation rate and an 80% 2-year survival rate. Below-knee amputation led to a similar ambulatory rate, but the 2-year survival in these patients was 52%. With more severe rear-foot ulcers and osteomyelitis, the ambulatory rate declined with each comorbidity. However, those whose foot was saved had a higher chance of walking than those who underwent amputation. Function and quality of life are the outcomes of interest and may be maximized through either limb salvage or amputation. Our job as physicians is to match the correct solution to the patients' lifestyle and their medical, physical and psychological conditions so they can achieve their desired level of activity as quickly as possible.
Multilayer Analysis of Spreading Resistance Measurements

Spreading resistance measurements provide a highly flexible technique for the determination of dopant profiles in semiconductors. However, because each measurement samples a greater depth into the sample than the depth difference between successive measurements, the direct conversion of resistivity readings to dopant concentration values will not yield a correct profile. The technique discussed in this report analyzes direct spreading resistance readings to deduce a "true" dopant profile. The model used is that of circular contacts to a laterally infinite medium which is partitioned vertically into layers of homogeneous resistivity, each layer corresponding to one spreading resistance measurement point. The analysis is performed by a computer program. Some detail in the development of the program is discussed. The results of this analysis technique compare favorably to profile results of other profiling techniques such as capacitance voltage and incremental sheet resistance on profile types to which they can be applied. The program execution time is usually fast enough that the computer charge is less than the direct charge billed for making the spreading resistance measurements.
Lichen-based indices to quantify responses to climate and air pollution across northeastern U.S.A

Lichens are known to be indicators for air quality; they also respond to climate. We developed indices for lichen response to climate and air quality in forests across the northeastern United States of America (U.S.A.), using 218–250 plot surveys with 145–161 macrolichen taxa from the Forest Inventory and Analysis (FIA) Program of the U.S. Department of Agriculture, Forest Service. Lichen indicator species for response to climate and air quality were selected using Indicator Species Analysis, correlations with environmental variables, and published literature. Ordinations were used to evaluate the strength and relationships of the final indices. The Pollution Index was calculated for a plot from abundances of 12 tolerant and 45 sensitive indicator species standardized by abundance of all lichen species. The Index was correlated with modeled deposition of acidifying sulfur and oxidized nitrogen and with lichen community ordination pollution axes. Analyses suggested separate response of lichens to fertilizing N (weak statistical support). The Climate Index, from abundances of 19 warmer and 47 cooler climate indicator species, was correlated with modeled minimum January and annual maximum temperatures, and with ordination climate axes. The two indices are statistically independent. Repeat sample variability for each index was 7–14.5% (lower with higher quality data), supporting detection of consistent trends of 16–20% change over time or variation across space. Variability of the Climate Index was more affected by data quality than that of the Pollution Index. The continuous gradient of Pollution Index values suggests the cleanest areas may have air pollution above a critical load to fully protect lichen communities. These Indices can be applied to track lichen responses using other data from our study regions; suitability should be tested before use outside of the study area.
Decontamination Methods for Wastewater and Stormwater Collection and Treatment Systems

Contamination of wastewater or stormwater systems may be one consequence of a terror attack involving chemical, biological, or radioactive agents.1 Such agents could enter the system through a contaminated water supply, runoff from a contaminated landscape, or effluent from decontamination operations. Once in a wastewater treatment plant, these agents may be removed or inactivated by conventional processes, but treatment residuals and collection system equipment, including piping, tanks, pumps, and related equipment, may themselves require decontamination or special treatment. This article discusses available information, technology, and methods for decontamination of wastewater and stormwater systems following a contaminating event. Keywords: decontamination; neutralization; cleanup; pipeline; residual contamination; radioactive agent; biological agent; chemical agent; treatment technology; terrorist event
Asymmetric Responses of Paspalum Species to a Soil Moisture Gradient

Anecdotal evidence suggests that dallisgrass (Paspalum dilatatum Poir.) and bahiagrass (Paspalum notatum Fluegge), two of the most troublesome weed species in managed turfgrass, are both drought and flood tolerant. Water table depth gradient tanks were employed to identify habitat specialization and competitive differences between dallisgrass and bahiagrass. Shoot and rhizome final biomass and survival were used as metrics for plants grown in monoculture or competition with hybrid bermudagrass (Cynodon transvaalensis Burtt Davy x C. dactylon (L.) Pers. 'Tifway 419') in sand or sandy loam soil. Shoot and rhizome growth of dallisgrass was greatest at the levels of highest soil moisture within each gradient tank regardless of soil type or competition. Percent survival of dallisgrass decreased to a low of 50% as depth to water table increased when grown as a monoculture and 12.5% when grown in competition with hybrid bermudagrass. Percent survival of bahiagrass was 100% regardless of water table depth, soil type, or competition. Shoot and rhizome growth of bahiagrass was greatest as depth to water table increased when grown in sandy loam soil. The opposite trend was observed when grown in sandy soil. Results suggest that dallisgrass may be more competitive with hybrid bermudagrass when volumetric soil moisture is high, while bahiagrass may be more competitive when volumetric soil moisture is low.
Radiation protection via the pinhole camera

Abstract A pinhole camera which simultaneously produces photographs and roentgenograms of any object which reflects light and emits secondary x-radiation has been described. Photographs and roentgenograms of a phantom's head, obtained with the pinhole camera and an x-ray machine, show the sources of secondary radiation which function when an examination of the patient's teeth is made by means of x-radiation. A method has been suggested for reducing the unnecessary exposure of both the patient and operator to scattered, secondary radiation.
Sub and near barrier fusion of neutron rich heavy nuclei – studies with radioactive ion beams

The availability of accelerated fission fragments at HRIBF allows us to study fusion reactions where one of the reactants is a short-lived exotic nucleus. Most interesting in this respect are entrance channels involving neutron-rich target and projectile – where enhanced survival probability of the compound system may allow the synthesis of heavier system. Much depends though on the dynamic evolution of the captured nuclei into a compound nucleus and the ensuing competition between fission and evaporation residue decay modes. Our studies of fusion between heavy neutron-rich nuclei are aimed at acquiring data that will lead to the understanding and eventually the ability to predict the probabilities for these different processes.
Studies of the Origin of Bacterial Viruses : VII. The effect of various mutagens (urethane, ethyl urethane, hydrogen peroxide, desoxycholate, maleic hydrazide, butadiene dioxide, triethylene melamine, versene, and acriflavine) on the proportion of virus-producing and streptomycin-resistant cells in cultures of B. megatherium 20delta.

The mutagens, urethane, ethyl urethane, hydrogen peroxide, desoxycholate, versene, maleic hydrazide, butadiene dioxide, and triethylene melamine, all increase the proportion of virus-producing cells and streptomycin-resistant cells in B. megatherium 20delta cultures to about the same extent. Acriflavine has no effect on the proportion of either type of cell. Triethylene melamine appears to cause mutations to occur without cell division.
Role modeling attitudes and physical activity and fitness promoting behaviors of HPERD professionals and preprofessionals.

(2001). Role Modeling Attitudes and Physical Activity and Fitness Promoting Behaviors of HPERD Professionals and Preprofessionals. Research Quarterly for Exercise and Sport: Vol. 72, No. 1, pp. 84-90.
Rat sexual behavior: Photographic analysis of the intromission response

High-speed photography of electrically monitored rat sexual behavior suggested that the intromission response may be analyzed into two components: a detection component, in which the male makes a variable number of very rapid shallow thrusts around and eventually into the vaginal opening, and a stimulation component, which consists of a single deep thrust into the vagina followed immediately by rapid and vigorous withdrawal and dismount. A suggestion is offered which relates the form of the behavior to the presumed method of penile receptor stimulation.
Non‐cross‐reactivity of antibodies to murine LDH‐C4 with LDH‐A4 and LDH‐B4

The induction of infertility by immunization with the sperm-specific lactate dehydrogenase, LDH-C4, suggests its use in a contraceptive vaccine. Development of an immunological contraceptive for human use, however, requires that there be no cross-reactions with somatic tissues. We have demonstrated, using enzyme-linked immunoabsorbence, solid-phase radioimmunoassay, and competitive inhibition radioimmunoassay, that antisera to LDH-C4 is specific and does not cross-react with the somatic isozymes, LDH-A4 and LDH-B4.
Kinase inhibition lengthens the period of the circadian pacemaker in the eye of Bulla gouldiana

Abstract The inhibition of protein kinase activity by the isoquinoline sulfonamide, H-8, lengthens the period of the Bulla ocular circadian rhythm in a dose-dependent manner. In addition, the phosphorylation of 5 proteins is markedly affected by H-8. The observed correlation between H-8's period lengthening effects, and its effects on the phosphorylation of specific proteins, suggests that: (1) these proteins are candidate components regulating the period of the circadian rhythm; and (2) the dailychanges in membrane potential underlying the circadian rhythm are mediated by similar mechanisms that serve to change neural function in other systems; modulation of protein kinases.
“They Read [the Truth] in Your Blood”: African American Women and Perceptions of HIV Health

In this article I examine variations in the ways in which low-income HIV-positive African American women in Midway, North Carolina engaged with and made meaningful laboratory-based knowledge of HIV disease. I highlight how women’s engagement with “blood-work,” as it was popularly called, reflected perceptions of survival with HIV disease and the material conditions and social relations in which these perceptions were embedded. Focusing less on the diagnostics themselves and more on the social contexts in which they became socially significant for study participants, I assert that “blood-work” provided a multiply constituted lens through which women expressed their subject positions and attendant material conditions within the context of a public health care program shaped by values associated with global neoliberalism.
Six signed Petersen graphs, and their automorphisms

Up to switching isomorphism, there are six ways to put signs on the edges of the Petersen graph. We prove this by computing switching invariants, especially frustration indices and frustration numbers, switching automorphism groups, chromatic numbers, and numbers of proper 1-colorations, thereby illustrating some of the ideas and methods of signed graph theory. We also calculate automorphism groups and clusterability indices, which are not invariant under switching. In the process, we develop new properties of signed graphs, especially of their switching automorphism groups.
Chronic restraint stress elicits a positive antidepressant response on the forced swim test

The present study investigated behavioral parallels between adaptation to stress and antidepressant treatment using the forced swim test. Restraint stress given repeatedly for 11 days significantly reduced immobility on this test. A single application of stress had no effect. The reduction in immobility produced by repeated restraint was quantitatively similar to that produced by repeated administration of desmethylimipramine. These results confirm previous findings of similarities in the behavioral and neurochemical response to chronic stress and chronic antidepressant treatment.
Nitric Oxide and Effects of Cationic Polypeptides in Canine Cerebral Arteries

Cationic polypeptides are released by activated leukocytes and may play an important role in the regulation of vascular tone. Effects of cationic polypeptides on cerebral vascular tone have not been studied. The present experiments were designed to determine if synthetic cationic polypeptides, poly-L-arginine and poly-L-lysine, affect the function of cerebral arteries. Rings of canine basilar arteries with and without endothelium were suspended for isometric force recording. Poly-L-arginine (10(-8)-10(-7) M) and poly-L-lysine (10(-8)-10(-7).M) caused endothelium-dependent relaxations. A nitric oxide synthase inhibitor, NG-nitro-L-arginine methyl ester (10(-4) M), and a nitric oxide scavenger, oxyhemoglobin (3 x 10(-6) M), inhibited relaxations in response to cationic polypeptides. Negatively charged molecules, heparin (1 U/ml) and dextran sulfate (10 mg/ml), also inhibited relaxations to poly-L-arginine or poly-L-lysine. Higher concentrations of poly-L-arginine (10(-6)-10(-5) M) and poly-L-lysine (10(-6)-10(-5) M) induced endothelium-independent contractions. A protein kinase C inhibitor, staurosporine (10(-8) M), abolished these contractions. Heparin (10 U/ml) and dextran sulfate (100 mg/ml) inhibited the contractile effect of cationic polypeptides but did not affect contractions to phorbol 12,13-dibutyrate. Poly-L-arginine (10(-6) M) and poly-L-lysine (10(-6) M) abolished endothelium-dependent relaxations in response to bradykinin (10(-10)-10(-6) M) or calcium ionophore A23187 (10(-9)-10(-6) M). Heparin (50 U/ml) and dextran sulfate (200 mg/ml) restored endothelium-dependent relaxations to bradykinin (10(-10)-10(-6) M) in arteries exposed to poly-L-arginine (10(-6) M) or poly-L-lysine (10(-6) M). These studies demonstrate that in the lower concentration range (10(-8)-10(-7) M), poly-L-arginine and poly-L-lysine induce endothelium-dependent relaxations by production of nitric oxide via charge-dependent activation of endothelial nitric oxide synthase. In the higher concentration range (10(-6)-10(-5) M), cationic polypeptides cause endothelium-independent contractions as well as impairment of endothelium-dependent relaxations in response to bradykinin and A23187. These contractions and inhibition of endothelium-dependent relaxations are also mediated by a charge-dependent mechanism and may involve activation of protein kinase C.
Search comparison in the infrared spectra for military operations in the urban terrain

This research compares target detection in the longwave and midwave spectral bands in urban environments. The Night Vision and Electronic Sensors Directorate (NVESD) imaged one hundred scenes at several Army Military Operations in the Urban Terrain (MOUT) sites during day and night. Images were resized to make the field-of-view (FOV) for each scene approximately the same. These images were then presented in a time-limited search perception experiment using military observers. Probabilities of detection were compared between the two spectral bands. Results from MOUT search were compared with previous modeling efforts.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Atomic structure at the (111) Si‐SiO2 interface

The structure and stoichiometry at the (111) Si‐SiO2 interface has been studied by ion backscattering channeling methods. In qualitative agreement with other oxide covered Si surfaces studied by this technique, we find the oxide to be stoichiometric to approximately one monolayer of the interface and a thin region (1–2 monolayers) of distorted Si crystal. Further measurements were carried out to evaluate the magnitude and direction of the Si atomic displacements at the interface.
Species diversity and the scale of the landscape mosaic : do scales of movement and patch size affect diversity

Abstract We use a combination of a model and empirical data to examine the relationship between the scale of the landscape mosaic and individual movement patterns on the measurement of local butterfly species diversity. In landscapes where patch sizes are smaller, the type of patch adjacent to the patch surveyed can influence both local species richness and incidence. In landscapes composed of larger patches, adjacency has no effect on species richness or incidence. We hypothesize that the mechanism for species enrichment is the potential for movement of individuals between habitats, resulting in either (a) spillover of species from the higher-diversity patches into other habitats, or (b) habitat sampling by species that benefit from the resources in adjacent patches. In order to determine whether landscape configuration alone can account for the observed patterns of diversity, we employ a simulation model. Simulation results suggest that both specialist and generalist butterflies can sample a much more diverse array of habitat types in a more fine-grained landscape.
p-Chloro-, p-bromo- and two polymorphs of p-iodo­aceto­phenone

The title p-haloaceto­phenones, C8H7XO (X = Cl, Br and I), have different packing modes. The chloro compound contains H⋯O and H⋯Cl contacts, but no Cl⋯O contacts. The bromo compound and one polymorph (A) of the iodo compound are isomorphous, with significant X⋯O contacts [Br⋯O = 3.320 (4) A and I⋯O = 3.374 (5) A]. In the other polymorph (B) of the iodo compound, the I⋯O distance is 3.082 (4) A. Both polymorphs contain C—H⋯π contacts; these contacts are shorter in A than in B.
Muc1 affects c-Src signaling in PyV MT-induced mammary tumorigenesis

MUC1 is an integral membrane mucin glycoprotein that is normally expressed on the apical surface of most simple, secretory epithelia and hematopoietic cells. Overexpression of aberrantly glycosylated MUC1 is a hallmark of many carcinomas including 90% of breast carcinomas. MUC1 has been shown to bind to c-Src tyrosine kinase in vitro, whereby c-Src phosphorylates the MUC1 cytoplasmic domain at a YEKV motif. c-Src is an extensively studied nonreceptor tyrosine kinase implicated in mammary tumorigenesis. Previously, mouse mammary tumor virus-driven polyoma middle T-antigen (MMTV-PyV MT) transgenic mice crossed onto a Muc1 null background exhibited a significant delay in tumor progression. c-Src has been shown to interact with PyV MT, and to play an integral and indispensable role in MMTV-PyV MT-induced mammary tumorigenesis. Here, we determine the effect of Muc1 expression on c-Src activation and signaling. Examination of MMTV-PyV MT glands on a wild-type or Muc1 null background demonstrates that Muc1 expression promotes c-Src signaling by influencing its association with known substrates such as the p85 subunit of phosphatidylinositol 3-kinase and β-catenin. These findings may provide a mechanism for the delay in tumor progression that is observed in the absence of Muc1.
Antibodies to native trna in nzb/nzw mice.

ANTIBODIES to native DNA, double-stranded RNA, and various synthetic polyribonucleotides occur with great frequency in patients with systemic lupus erythematosus (SLE)1. These antibodies are also present in the New Zealand mouse, particularly the NZB/NZW F1 hybrid, which is considered a good animal model for human SLE2. We report here the presence and characterisation of antibodies that bind tRNA, specifically in its native conformation, in sera from old NZB/NZW mice.
Early ultrasound for fetal anatomy in the obese pregnant woman

ALYSSA MILLS, BRITA BOYD, BARBARA HERTZBERG, HAYWOOD BROWN, GEETA K. SWAMY, Duke University, Obstetrics & Gynecology, Durham, North Carolina, Duke University, Radiology, Durham, North Carolina OBJECTIVE: To determine whether early transabdominal (TA) plus transvaginal (TV) ultrasound (US) can optimize standard fetal anatomic survey and can be performed in a shorter amount of time. STUDY DESIGN: In this prospective, observational pilot study, 20 obese (BMI R30 kg/m2) pregnant women underwent US for fetal anatomy at 14-16 wks (US1) and again at 18-20 wks (US2). TV & TA imaging were performed to complete US1. Images were independently reviewed by 3 physicians and individual structures were described as not visualized (0 points), suboptimally visualized (1 point), or optimally visualized (2 points). Points were added for a perfect score of 6/structure, 126/US overall. Kappa statistics were used to assess inter-reviewer agreement. Paired t-test was used to compare scores, p!.05 significant. RESULTS: Mean BMI at US1 was 40.5 kg/m2. Both US took similar time to complete (mean 35 minutes for US1, 37 for US2, p=0.6). Inter-reviewer agreement ranged .12-.78. Cardiac anatomy and kidneys were equally wellvisualized at both US; however other structures were more often optimally visualized at US2. Overall, US2 performed better than US1. CONCLUSION: Early US in obese women was useful for some structures, but should not replace US at 18-20 wks.
Production of dihydroisocoumarins in Fusarium verticillioides by swapping ketosynthase domain of the fungal iterative polyketide synthase Fum1p with that of lovastatin diketide synthase

Filamentous fungi are rich in polyketide synthase (PKS) genes. However, the polyketide products synthesized by the PKS remain largely unexplored. Even less is known about the mechanism by which the fungal PKS controls the structure of the products. Using a genetic system that allows specific and functional changes of the catalytic domains of FUM1, which is a PKS gene responsible for the biosynthesis of the highly reduced, linear 18-carbon polyketide chain of mycotoxin fumonisins in Fusarium verticillioides, we obtained fungal mutants containing a chimeric FUM1, in which the ketosynthase domain had been replaced by that of lovastatin diketide synthase gene. The mutants produced dihydroisocoumarins, which are known to have antimalarial, antifungal, and antituberculosis activities and had never been isolated from a Fusarium species. This work represents the first successful genetic manipulation of an iterative polyketide synthase gene to produce new, biologically active metabolites in a filamentous fungus. T...
Regulatory Reform and Bureaucratic Responsiveness to Firms: the Impact of User Fees in the FDA

This paper examines the impact of user fees on the speed of new-drug review and on the responsiveness of FDA reviewers to pharmaceutical firms. User fees are expected to alter FDA behavior and responsiveness to pharmaceutical firms because they give regulators a financial incentive to process more new-drug applications and because they convey information to regulators that may reduce type I error. The analysis examines the variation in FDA review times for new drugs approved between 1990 and 1995 as a function of differences that exist among firms and drugs. Specifically, it compares estimates of regulator responsiveness to several firm and drug characteristics before and after the introduction of user fees. The results show that user fees produced a significant change in FDA behavior. Regulators have become less responsive to the differences among firms since the introduction of user fees, which suggests that the reform has led to more equity in the new-drug review process. In addition, the FDA has expedited the review of new drugs, especially the most therapeutically novel drugs, which suggests that politicians have been fairly successful in designing a reform to realign regulatory incentives in the FDA.
“Charge-Transfer” Process at Graphite/Electrolyte Interface and the Solvation Sheath Structure of Li + in Nonaqueous Electrolytes

The temperature- and electrolyte-dependences of the so-called charge-transfer process at graphite/electrolyte interface were investigated with impedance analyses at lithiation potential (0.15 V vs Li), and characteristic correlations between the activation energies of the process and the electrolyte compositions (such as solvent ratio and salt concentration) were established. It was found that the solvation sheath structure of Li + is dependent on the ratios of cyclic (such as EC) to linear carbonates (such as DMC), which in turn results in different chemistries of graphite/electrolyte interfaces and dictates the Li + -transport across such interfaces. The interdependences thus revealed could serve as useful guidelines to tailoring electrolytes of Li-ion batteries for sub-zero temperature applications.
Defect formation in SiO2 glass during fracture

Abstract It was found that paramagnetic defects, including E′ centers and oxygen hole centers, were created in high-purity silica glass during mechanical crushing in all test environments except water. The number of E′ and oxygen hole centers was proportional to the surface area of the powdered sample, but it was considered that the defects exist in a sub-surface layer. The combined defect center signal intensity appears to correlate with the surface energy of the glass during fracture. From the temperature dependence of the signal decay in air, the activation energy of the process was found to be ∼ 62 ± 3 kJ/mol. This suggests that water diffusion into the glass is the rate controlling process. The absence of any combined defect center signal in SiO 2 glass crushed in water is attributed to the entry of water into the glass structure during fracture and the transformation of the E′ and oxygen hole defects to a non-paramagnetic state or form.
Application of ion exchangers to recovery of metals from semiconductor wastes

Abstract This paper describes the equilibrium behaviour of a wastewater resembling that produced during semiconductor and printed circuit board manufacture when contacted with a chelating ion exchange resin (Chelex-100; Bio-Rad Laboratories). Distribution coefficients (solid phase metal concentrations/soluble metal concentration) were calculated, and it was determined that the order of affinity was Cu>Pb>Ni>Cr(III). Comparison of the distribution coefficient values obtained in these multicomponent studies with those obtained in prior single component investigations revealed gross discrepancies. Correction of the current and single component data for soluble phase complexation using an equilibrium computer model reduced the deviations. Computed selectivity coefficients based on calculated free ionic metal concentrations showed substantial variation with solid phase composition, indicating that significant solid phase non-idealities existed in this system. Regeneration experiments on spent resin indicated that simple acid regeneration could recover more than 90 percent of the exchanged copper. Based on this study it would appear that treatment of mixed metal wastes generated in printed circuit board and electroplating operation by ion exchange is a technically feasible process for removal and recovery of metals, especially copper.
GENIE: A Generalized Array Optimizer for VLSI Synthesis

A new generalized array optimization scheme is presented which solves the problem of efficient automatic layout of multi-level CMOS and NMOS logic circuits. The new approach has been implemented in the program GENIE which can be used for the multiple folding of PLAs, as well as for compacting gate matrix layouts, SLAs, and Weinberger arrays. The cells in the array can be of non-uniform sizes and any form of constraint can be placed on the input and output terminals. The generalized array optimizer uses the combinatorial optimization technique called Simulated Annealing. Results obtained are uniformly better than existing specialized array optimizers and folding programs, particularly when the inputs locations are constrained. GENIE is the first program to produce high-quality, automated SLA implementations.
A Public Choice Perspective on the Subsidization of Private Industry: A Case Study of Three Cities and Three Stadiums

This article employs the public choice perspective to explain and evaluate the outcomes of publicly subsidized economic development projects. Despite the questionable impacts of economic developmen...
Nonparallel stability of three-dimensional flows

The linear stability of three-dimensional incompressible, isothermal, nonparallel boundary-layer flows has been investigated. The method of multiple scales is used to derive the partial-differential equations that describe the spatial modulations of the amplitude, phase and wavenumber of a disturbance. Group velocities are used to determine the disturbance growth direction. The envelope method is used to calculate the logarithmic amplitude growth rate N. The theory is applied to the flows over a swept-back tapered wing with boundary-layer suction. Results of such analysis for the X-21 wing are discussed. It is found that the nonparallel effects for this wing is substantial.
‘America Needs Farmers’: Communal Identity, the University of Iowa Football Team and the Farm Crisis of the 1980s

During the 1980s, Iowa farmers struggled through grave economic situations comparable to the Depression. Many farmers were forced to leave family farms, unable to pay their large debts. At the same time, the Hayden Fry-led University of Iowa football team achieved tremendous success, moving to the top of national polls in 1985. This paper examines how the success of the University of Iowa football team impacted on the farm community. Those in rural communities around the state, many struggling with their own achievement and identity, rallied around the success of the Hawkeyes. The topic helps delineate the relationship between intercollegiate athletic programmes and surrounding communities. ‘Iowa football reflects the mores of a greater community which is all of Iowa. There are striking similarities between the uphill fight of the Hawkeyes to win football recognition among the toughest foes, and the uphill fight of the university itself to win a higher place of honor, respect and proud support among its o...
Loss aversion, equity constraints and seller behavior in the real estate market☆

Abstract I develop an estimation strategy that can point identify the effects of loss aversion and equity constraints on selling prices using a long panel of data from the San Francisco Bay Area real estate market. I find strong evidence that owners facing nominal losses on their housing investments and owners with high LTV ratios sell for higher prices, on average, and the effects are larger than previously thought. I also present new empirical findings that support the theory that down-payment constraints or other institutional details of the mortgage market drive the relationship between LTV and prices. The results have implications for understanding how local housing market variables such as prices and volume are determined in slow markets.
Structures of a monomeric and a dimeric Ni(II) complex containing 2-acetylpyrrole

Abstract The structures of two derivatives of Ni(II) containing 2-acetylpyrrole are reported. The first compound is a dimer containing four 2-acetylpyrrole and two isopropylamine molecules, with the nickel centers bridged by carbonyl oxygen atoms from two of the four 2-acetylpyrrole groups. The second derivative is a monomer containing two n-butylamine and two 2-acetylpyrrole molecules, with the latter arranged in a planar fashion around the nickel center. Crystals of the dimer are triclinic with space group P 1 with a=8.281(2), b=9.694(2), c=11.495(2) A, α=110.08(3), β=105.57(3), γ=99.35(3)°, V=801.1(2) A3 and Z=1. Crystals of the monomer are triclinic with space group P 1 with a = 5.626(2), b = 9.803(2), c = 10.792(2) A, α = 74.96(2), β = 81.81(2), γ=83.34(2)°, V=566.9(2) A3 and Z=1.
Effect of Surface Energy on the Mechanical Strength of a High‐Silica Glass

The mechanical strength of high-silica glass was measured in various organic liquids and in water. The extent of the surface-energy reduction of glass was also estimated from the swelling or the expansion of porous glass, immersed in liquids, by measuring the stress in the core of a partially leached glass. The stress, normalized to the value in water, showed a good correlation with the heat of immersion, which is a measure of the surface-energy reduction. Mechanical strength and the stress due to swelling showed a reasonable correlation, suggesting that the strength variation in various liquids is due to the surface-energy variation and the accompanying force which caused the swelling.
Ageing and the epidemiology of multimorbidity

The world's population is ageing and an important part of this demographic shift is the development of chronic illness. In short, a person who does not die of acute illnesses, such as infections, and survives with chronic illnesses is more likely to develop additional chronic illnesses. Chronic respiratory diseases are an important component of these diseases associated with ageing. This article reviews the relationship between ageing and chronic respiratory disease, and also how certain chronic diseases cluster with others, either on the basis of underlying risk factors, complication of the primary disease or other factors, such as an increased state of inflammation. While death is inevitable, disabling chronic illnesses are not. Better understanding of how individuals can age healthily without the development of multiple chronic illnesses should lead to an improved global quality of life.