cssi/SciSciGPT-SciSciNet huggingface dataset:
Selective Uptake of Radiolabeled Annexin V on Acute Porcine Left Atrial Thrombi

Background Annexin V is a human phospholipid binding protein that binds to activated platelets in vitro. We sought to determine the potential of this agent for imaging intracardiac thrombi in swine. Methods and Results Left atrial thrombi were formed by crush injury. In initial nonimaging experiments using intravenous 125 I-labeled human annexin V, the mean thrombus/whole blood ratio was 13.4±4.8 for the entire thrombus using well counting of resected specimens (n=8). Using intravenously injected 99m Tc-labeled human annexin V, the left atrial thrombus/blood ratio by well counting was similar (14.2±10.6 for the entire thrombus and 26.2±14.9 for the peak section) (n=12). The ratio for a control protein, 125 I-ovalbumin, was only 1.0±0.2. 99m Tc tomographic imaging was positive (n=10) or equivocal (n=2) in all experiments with but negative in 10 controls without left atrial thrombi. By region-of-interest analysis of the tomographic images, the mean left atrial appendage/blood ratio at 2 hours in animals with a thrombus was 3.90±1.12 compared with 0.84±0.10 in closed chest controls and 1.01±0.23 in open chest controls ( P Conclusions We conclude that 99m Tc-labeled human annexin V detects acute left atrial thrombi in vivo in swine. The combination of a new thrombus detection agent, annexin V, with a 99m Tc label may allow in vivo imaging of thrombi in humans.
A broad specificity nucleoside kinase from Thermoplasma acidophilum

The crystal structure of Ta0880, determined at 1.91 A resolution, from Thermoplasma acidophilum revealed a dimer with each monomer composed of an α/β/α sandwich domain and a smaller lid domain. The overall fold belongs to the PfkB family of carbohydrate kinases (a family member of the Ribokinase clan) which include ribokinases, 1-phosphofructokinases, 6-phosphofructo-2-kinase, inosine/guanosine kinases, fructokinases, adenosine kinases, and many more. Based on its general fold, Ta0880 had been annotated as a ribokinase-like protein. Using a coupled pyruvate kinase/lactate dehydrogenase assay, the activity of Ta0880 was assessed against a variety of ribokinase/pfkB-like family substrates; activity was not observed for ribose, fructose-1-phosphate, or fructose-6-phosphate. Based on structural similarity with nucleoside kinases (NK) from Methanocaldococcus jannaschii (MjNK, PDB 2C49, and 2C4E) and Burkholderia thailandensis (BtNK, PDB 3B1O), nucleoside kinase activity was investigated. Ta0880 (TaNK) was confirmed to have nucleoside kinase activity with an apparent KM for guanosine of 0.21 μM and catalytic efficiency of 345,000 M(-1) s(-1) . These three NKs have significantly different substrate, phosphate donor, and cation specificities and comparisons of specificity and structure identified residues likely responsible for the nucleoside substrate selectivity. Phylogenetic analysis identified three clusters within the PfkB family and indicates that TaNK is a member of a new sub-family with broad nucleoside specificities. Proteins 2013. © 2012 Wiley Periodicals, Inc.
Definition of the boundaries of the origin of DNA replication in simian virus 40

Abstract We have determined by use of DNA sequencing techniques the exact location of the deletion in d1 892, a viable deletion mutant of Simian virus 40 (SV40) reported to map very near the unique replication origin or SV40. With the help of this localization we have narrowed down the boundaries of the replication origin to 85 nucleotides within the sequence of SV40.
Cable dynamics—a finite segment approach

Abstract The paper presents and discusses a nonlinear, three-dimensional, finite-segment, dynamic model of a cable or chain. The model consists of a series of links connected to each other by ball-and-socket joints. The size, shape, and mass of the links is arbitrary. Furthermore, these parameters may be distinct for each link. Also, the number of links is arbitrary. The model allows an arbitrary force system to be applied to each link. The model is used to develop a computer code which consists primarily of subroutines containing algorithms to develop the kinematics, force systems, and governing dynamical equations. Although the integration of the equations is performed with a Runge-Kutta algorithm, the code is developed so that any other suitable integration technique or algorithm may be substituted. The input for the code requires the following: the number of links; the mass, centroidal inertia matrix, mass-center position, connection point, and external forces on each link; and the time history of the specified variables. The output consists of the time history of each variable, the position, velocity, and the acceleration of the mass-center of each link, and the unknown forces and moments. An example problem is presented which describes the motion of a sphere drug through water by a partially submerged cable suspended from a rotating surface crane. Viscous forces of the water are included. Although the example simulates a typical nautical rig. its inclusion in the paper is introduced primarily to illustrate the capability of the model.
On the stability of solitary waves for the ostrovsky equation

Considered herein is the stability of solitary-wave solutions of the Ostrovsky equation which is an adaptation of the Korteweg-de Vries equation widely used to describe the effect of rotation on the surface and internal solitary waves or the capillary waves. It is shown that the ground state solitary waves are global minimizers of energy functionals with the constrained variational problem and are deduced to be nonlinearly stable for the small effect of rotation. The analysis makes frequent use of the variational properties of the ground states.
Describing Teacher–Student Interactions: A Qualitative Assessment of Teacher Implementation of the 7th Grade keepin’ it REAL Substance Use Intervention

Variations in the delivery of school-based substance use prevention curricula affect students’ acquisition of the lesson content and program outcomes. Although adaptation is sometimes viewed as a lack of fidelity, it is unclear what types of variations actually occur in the classroom. This observational study investigated teacher and student behaviors during implementation of a middle school-based drug prevention curriculum in 25 schools across two Midwestern states. Trained observers coded videos of 276 lessons, reflecting a total of 31 predominantly Caucasian teachers (10 males and 21 females) in 73 different classes. Employing qualitative coding procedures, the study provides a working typology of implementation patterns based on varying levels of teacher control and student participation. These patterns are fairly consistent across lessons and across classes of students, suggesting a teacher-driven delivery model where teachers create a set of constraints within which students vary their engagement. Findings provide a descriptive basis grounded in observation of classroom implementation that can be used to test models of implementation fidelity and quality as well as impact training and other dissemination research.
Algebraic Geometric Codes over Rings

Abstract The techniques of algebraic geometry have been widely and successfully applied to the study of linear codes over finite fields since the early 1980s. Recently, there has been an increased interest in the study of linear codes over finite rings. In this paper, we combine these two approaches to coding theory by introducing the study of algebraic geometric codes over rings. In addition to defining these new codes, we prove several results about their properties.
Mechanisms for naphthalene removal during electrolytic aeration.

Abstract Batch tests were performed to investigate chemical and physical processes that may result during electrolytic aeration of a contaminated aquifer using naphthalene as a model contaminant. Naphthalene degradation of 58–66% took place electrolytically and occurred at the same rates at a pH of 4 and 7. 1,4-naphthoquinone was identified as a product of the electrolysis. Stripping due to gases produced at the electrodes did not result in any naphthalene loss. Hydrogen peroxide (which may be produced at the cathode) did not have any effect on naphthalene, but the addition of ferrous iron (which may be present in aquifers) resulted in 67–99% disappearance of naphthalene. Chlorine (which may be produced from the anodic oxidation of chloride) can effectively degrade naphthalene at pH of 4, but not at a pH of 7. Mono-, di- and poly chloronaphthalenes were identified as oxidation products. Ferric iron coagulation (due to the oxidation of ferrous iron) did not significantly contribute to naphthalene loss. Overall, electrolytic oxidation and chemical oxidation due to the electrolytic by-products formed are significant abiotic processes that could occur and should be accounted for if bioremediation of PAH-contaminated sites via electrolytic aeration is considered. Possible undesirable products such as chlorinated compounds may be formed when significant amounts of chlorides are present.
27.8 A static contention-free single-phase-clocked 24T flip-flop in 45nm for low-power applications

Near-threshold computing (NTC) is an attractive solution to stagnating energy efficiencies in digital integrated circuits, arising from slowed voltage scaling in nanometer CMOS [1-2]. The design of sequential elements for NTC, as well as in voltage-scaled systems operating at both near-threshold and super-threshold, has not been extensively studied. However, it is well known that sequential elements have a strong sensitivity to process variations in NTC [2], which can have a significant impact on system yield and power consumption. In order to achieve reliable energy-efficient operation across a wide operating voltage range, a flip-flop should have the following attributes: 1) static operation, since dynamic nodes are highly susceptible to PVT variations at low voltage; 2) contention-free transitions, since ratioed logic has poor robustness across the wide range of device ION/IOFF ratios incurred with voltage scaling; 3) single-phase clocking, which avoids toggling of internal clock inverters and the corresponding power penalty; 4) minimum or no area penalty compared to conventional flip-flops.
Paramagnetic resonance study of radiation damage in lithium fluoride

Abstract The low temperature annealing processes in LiF crystals X-rayed at 77°K have been studied by means of paramagnetic resonance. Four types of hole centers ( V -type centers), the structures of which are known from previous work, play an important part; namely, the self-trapped holes, the H -centers, the V F -centers and the V t -centers. The relative concentrations of these defects have been measured after X-irradiation at 77°K and after subsequent pulse annealing at successively higher temperatures. Four temperature intervals were found in which the paramagnetic resonance spectra undergo significant changes in intensity. There seems to be a one-to-one correspondence between the annealing processes observed by means of paramagnetic resonance and those detected by other investigators by means of thermoluminescence, conductivity, changes of the optical absorption and of the crystal volume.
Fuzzy-Trace Theory and False Memory

A key problem confronting theories of false memory is that false-memory phenomena are so diverse: Some are characteristic of controlled laboratory tasks, others of everyday life; some occur for traumatic events with legal consequences, others for innocuous events; some are characteristic of one developmental level, others of another developmental level. Fuzzy-trace theory explains false memories via a small set of principles that implement a single representational distinction. Those principles generate new predictions, some of which are counterintuitive.
Experimental Transmission of Toxoplasma gondii by Cockroaches

The Madeira cockroach, Leucophaea maderae, and the American cockroach, Periplaneta americana, were evaluated as transport hosts of Toxoplasma gondii. After starved cockroaches were allowed access to feline feces containing infectious oocysts of Toxoplasma, their feces and digestive tracts were tested for infectivity in mice. Toxoplasma was isolated from the digestive tract of a cockroach as long as seven days after contact with feline feces and from cockroach feces as long as nine to 10 days after contact. Cockroach feces, stored at room temperature and humidity, remained infectious for mice for up to 17 days. The modes of transmission of Toxoplasma gondii, a protozoan parasite infecting man and a variety of warm-blooded animals, are not well understood. Toxoplasma can be transmitted from mother to fetus, and infection is known to occur after consumption of raw or rare meat containing the cyst stage. However, the modes of noncongenital infection in herbivorous animals and in humans who do not eat raw meat have yet to be elucidated. Recently, a highly resistant oocyst stage of the parasite was discovered in feces of experimentally and naturally infected cats [1-7]. This stage readily infects most mammals tested by the oral route ([2] and authors' unpublished observations), and it is presumed to be as infectious for man. Two questions remain: (1) Are the majority of human infections with Toxoplasma the result of exposure to the oocyst stage, as is now generally presumed? (2) If so, what is the usual method(s) of exposure? There is some epidemiologic evidence suggesting that under certain conditions man might acquire toxoplasma infection by ingesting food
Light-activated GTPase in vertebrate photoreceptors.

IN studies of the regulation of cyclic GMP levels by light we found that rod outer segment disk membranes contain a cyclic GMP phosphodiesterase (PDE) with a molecular weight of 240,000, whose activation depends on the photoisomerisation of rhodopsin the presence of a nucleoside triphosphate1–3. We report here an additional light-dependent enzyme activity, the hydrolysis of GTP to form GDP and inorganic phosphate, which functions as another enzymatic component in the regulation of photoreceptor guanosine nucleotide levels by light. This GTPase has the action spectrum of rhodopsin and is half-maximally activated by bleaching only one in 2,000 rhodopsins. The enzyme has an apparent Km for GTP of 0.5 µM. GTPase activity can be quantitatively removed from the disk membranes and the activity can be fully restored to the disk membranes by a partially purified heat labile protein with an apparent molecular weight of 32,000.
Pulsed laser deposition of YBCO thin films on IBAD–YSZ substrates

High-quality YBa2Cu3O7−x (YBCO) films were fabricated on yttria-stabilized zirconia (YSZ)-buffered Hastelloy C276 substrates by pulsed laser deposition. YSZ was grown by ion-beam-assisted deposition. A thin (≈10 nm) CeO2 layer was deposited before the deposition of YBCO. The crystalline structure and biaxial texture of the YBCO film and the buffer layer were examined by x-ray diffraction 2θ-scan, -scan and pole-figure analysis. Epitaxial growth of the YBCO film on the buffer layer was observed. Full width at half maximum (FWHM) value of 7.4° was measured from the -scan of YBCO(103). Raman spectroscopy showed compositional uniformity and phase integrity in the YBCO films. Surface morphologies of the YBCO films were examined by scanning electron microscopy. Comparative studies indicated that the CeO2 buffer layer significantly improves the structural alignment and superconducting properties of YBCO films. Tc = 90 K, with sharp transition, and transport Jc = 2.2 × 106 A cm−2 at 77 K in zero-external field were obtained on the 0.5 μm thick YBCO films. The dependence of Jc on the FWHM of the YBCO(103) -scan indicated that high Jc is associated with low FWHM.
Identifying housing and meteorological conditions influencing residential air exchange rates in the DEARS and RIOPA studies: development of distributions for human exposure modeling

Appropriate prediction of residential air exchange rate (AER) is important for estimating human exposures in the residential microenvironment, as AER drives the infiltration of outdoor-generated air pollutants indoors. AER differences among homes may result from a number of factors, including housing characteristics and meteorological conditions. Residential AER data collected in the Detroit Exposure and Aerosol Research Study (DEARS) and the Relationships of Indoor, Outdoor and Personal Air (RIOPA) study were analyzed to determine whether the influence of a number of housing and meteorological conditions on AER were consistent across four cities in different regions of the United States (Detroit MI, Elizabeth NJ, Houston TX, Los Angeles, CA). Influential factors were identified and used as binning variables for deriving final AER distributions for the use in exposure modeling. In addition, both between-home and within-home variance in AER in DEARS were quantified with the goal of identifying reasonable AER resampling frequencies for use in longitudinal exposure modeling efforts. The results of this analysis indicate that residential AER is depended on ambient temperature, the presence (or not) of central air conditioning, and the age of the home. Furthermore, between-home variability in AER accounted for the majority (67%) of the total variance in AER for Detroit homes, indicating lower within-home variability. These findings are compared with other previously published AER distributions, and the implications for exposure modeling are discussed.
FROM THE BLAZAR SEQUENCE TO THE BLAZAR ENVELOPE: REVISITING THE RELATIVISTIC JET DICHOTOMY IN RADIO-LOUD ACTIVE GALACTIC NUCLEI

We revisit the concept of a blazar sequence that relates the synchrotron peak frequency (Vpeak) in blazars with synchrotron peak luminosity (Lpeak, in vLv) using a large sample of radio-loud AGN. We present observational evidence that the blazar sequence is formed from two populations in the synchrotron Vpeak - Lpeak plane, each forming an upper edge to an envelope of progressively misaligned blazars, and connecting to an adjacent group of radio galaxies having jets viewed at much larger angles to the line of sight. When binned by jet kinetic power (Lkin; as measured through a scaling relationship with extended radio power), we find that radio core dominance decreases with decreasing synchrotron Lpeak, revealing that sources in the envelope are generally more misaligned. We find population-based evidence of velocity gradients in jets at low kinetic powers (approximately 10(exp 42) - 10(exp 44.5) erg s(exp -1)), corresponding to FR I radio galaxies and most BL Lacs. These low jet power 'weak jet' sources, thought to exhibit radiatively inefficient accretion, are distinguished from the population of non-decelerating, low synchrotron-peaking (LSP) blazars and FR II radio galaxies ('strong' jets) which are thought to exhibit radiatively efficient accretion. The two-population interpretation explains the apparent contradiction of the existence of highly core-dominated, low-power blazars at both low and high synchrotron peak frequencies, and further implies that most intermediate synchrotron peak (ISP) sources are not intermediate in intrinsic jet power between LSP and high synchrotron-peaking (HSP) sources, but are more misaligned versions of HSP sources with similar jet powers.
Rapid neutralization and charge equilibration of highly charged ions at grazing incidence on a surface

We have measured the experimental final average charge states for ${\mathrm{C}}^{q+}$ $(q=2,4,6+),$ ${\mathrm{Ar}}^{q+}$ $(q=8,16,17+),$ and ${\mathrm{Fe}}^{q+}$ $(q=5,10,15,22+)$ ions grazingly reflected from a smooth graphite surface as a function of the initial charge state, impact angle, and impact velocity $(vl1\mathrm{a}.\mathrm{u}.).$ The final charge state is almost independent of the initial charge state of the ion and of the impact angle for all investigated ions and impact velocities, which indicates that the projectile experiences a charge-state equilibration during the grazing-angle collision. The velocity dependences of the average charge state after a grazing-angle collision and after foil penetration were found to be similar. However, the grazing-angle collision yields the lower average charge state. The three kinds of projectiles used in this work show similar properties during the scattering, despite their different electronic structures or masses, which suggests that our results can be generalized for any kind of highly charged ion.
On dynamics of certain Cantor sets

Abstract We answer the following question: If p and q are positive integers greater than 1 and C p is the set of all numbers in [0, 1] which can be expressed in base p without using a nonempty finite collection of finite length patterns in Z p , under what conditions does C p contain a number whose base q expansion contains all patterns of finite length?
Helminth Parasites of Unisexual and Bisexual Whiptail Lizards (Teiidae) in North America. I. The Colorado Checkered Whiptail (Cnemidophorus tesselatus)

Eleven of 27 (41%) parthenogenetic Colorado checkered whiptails (Cnemidophorus tesselatus) from four counties of western and southwestern Texas were infected with one or more helminths. These included a linstowiid cestode (Oochoristica sp.), a larval spi-rurid nematode (Physaloptera sp.) and two species of oxyurid nematodes (Parathelandros texanus and Pharyngodon warneri). This note, the first in a series of reports on helminths of Cnemidophorus spp., represents the first record of parasites from C. tesselatus.
Abstract P1-09-03: The use of MRI in the evaluation of breast cancer

Background: The availability of Magnet Resonance Imaging (MRI) has increased in the United States over the last decade. Its use for the diagnosis and staging of breast cancer remains undetermined. We examined the trends and frequency of MRI use in women with newly diagnosed breast cancer in Texas and evaluated the factors associated with a receipt of an MRI. Methods: The Texas Cancer Registry (TCR) Medicare linked data were used to identify incident breast cancer cases between 1/1/2003-12/30/2007. We included female patients, 65 and older enrolled in both Medicare Parts A and B for 3 months prior to diagnosis and 12 months after diagnosis, and not enrolled in an HMO plan during the same period. Patients diagnosed at autopsy were excluded. Bivariate and multivariate logistic regression analysis was performed to determine the factors associated with receipt of MRI. A Cochran-Armitage trend test was performed to examine the trends in use of MRI over study period. A p-value <0.05 was considered statistically significant. Results: Of the 292,297 patients diagnosed with breast cancer between 2003 and 2007, 18, 856 patients met the inclusion criteria. Of these, 1268 (6.72%) received an MRI. The overall use of breast MRI has increased significantly in Texas from 2.25% of women diagnosed in 2003 to 13.9% of women diagnosed in 2007 (p<0.001). In the bivariate analysis we found that age, race, number of comorbidities, poverty level, education level, and region were associated with the receipt of MRI at the time of breast cancer diagnosis. In the multivariate analysis after adjusting for those covariates, we found that women of advancing age, black race (34%) and presence of any comorbidity (29%) to be significantly less likely to get an MRI, while those with regional disease and higher level of education were more likely to receive MRI (table 1). Conclusion: Breast MRI in newly diagnosed breast cancer in the state of Texas increased six fold during the study period. While use has increased in Texas, receipt of MRI does not appear to be uniform. To identify the group of women who would benefit most from MRI, more in depth analyses of the role of socio-economic components on receipt of MRI and patient outcomes is needed. View this table: Multivariate analysis: Odds of receiving an MRI at the time of breast cancer diagnosis Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-09-03.
Discriminations among perceptual and symbolic stimuli

This research compares the time required for perceptual discriminations among pairs of physically present objects (circles) with the time required to discriminate pairs of symbols Inonsense syllables) that subjects learned to associate uniquely with each of the circles. Four experiments show very large differences between symbolic and perceptual discriminations. Discrimination times for the perceptual stimuli declined systematically as their size ratio increased, but discriminations among the associated nonsense syllables showed only a strictly ordinal effect of position in the series. Discriminations among the symbolic stimuli showed a large semantic congruity effect, but the perceptual stimuli showed none. The research does not replicate previous results showing similarities between perceptual and symbolic processing suggestive of image processing. We conclude that in the symbolic task subjects use only ordinal information rather than images or analog representations of the associated circles. We propose that perceptual discriminations show a semantic congruity effect only when they are processed as if the perceptual stimuli were symbolic.
Diagram for a small planet: The production and Ecosystem possibilities curve

Abstract With the development of the GPI there is now an ecological alternative to GDP for measuring a country's economic performance, but we still lack an ecological alternative to the PPC for illustrating a country's economic problem. The diagram suggested here illustrates a country's production and ecosystem possibilities — including climate stability, flood control, carbon sequestration, aquifer recharge, scenery, recreation, biological diversity, and so on. Burning a rainforest to clear the land shifts a country's PPC outward, giving the visual impression of an unmitigated improvement; but such development causes a movement along the country's PEPC, as ecosystem services are transformed into GDP. The slope of the PEPC is the marginal rate of transformation, which equals the ratio of the land's marginal marketable product to its marginal ecosystem product. Changes in technology create substitution and income effects that help explain the enclosure movement and the environmental Kuznets curve. Much as employment of the human resource can be restrained to allow more leisure, development of the natural resource can be restrained to preserve more ecosystem services. Commercial lobbying interests and rivalries for positional goods create distortions that move a country along its PEPC to a materialistic misallocation, with too little conservation. An idealistic misallocation is also possible, with too much preservation of the natural environment. Small is beautiful, up to a point, and that is evident in this diagram. Jacob Viner's [Viner, J., 1937. Studies in the Theory of International Trade. Harper and Brothers, New York] analytical objections to the PPC are revived.
MRI characteristics and classification of peripheral vascular malformations and tumors

Vascular malformations and tumors comprise a broad spectrum of lesions that can cause significant morbidity and even mortality in children and adults. Classification of vascular malformations into high flow and low flow has significant impact on management since the main treatment of the former is transarterial embolization and the later percutaneous sclerotherapy. Magnetic resonance imaging (MRI) is a noninvasive effective tool for imaging and classification of vascular malformations based on the presence of lobulated masses, signal voids, and hemodynamic flow characteristics. MRI also provides details about anatomic extent of the lesion, proximity to vital structures, and involvement of multiple tissue planes. The prototype of vascular tumors is infantile hemangioma with its typical involution after a proliferative phase during infancy. Hemangioma appears as a distinct intensely enhancing soft tissue mass with enlarged feeding arteries and draining veins. Less common vascular tumors include congenital hemangioma, kaposiform hemangioendothilioma, angiolipoma, angiosarcoma, and hemangiopericytoma.
Renormalization-group calculation of the critical-point exponent η for a critical point of arbitrary order

The critical-point exponent $\ensuremath{\eta}$ for a critical point of order $\mathcal{O}$ in dimensions less than ${d}_{\mathcal{O}}\ensuremath{\equiv}\frac{2\mathcal{O}}{(\mathcal{O}\ensuremath{-}1)}$, is calculated to leading nonvanishing order in the parameter ${\ensuremath{\epsilon}}_{\mathcal{O}}\ensuremath{\equiv}{d}_{\mathcal{O}}\ensuremath{-}d$. The result is given for $n$-component isotropically interacting magnetic systems. For Ising systems, $n=1$, the result is ${\ensuremath{\eta}}_{\mathcal{O}}=\frac{{\ensuremath{\epsilon}}_{\mathcal{O}}^{2}4{(\mathcal{O}\ensuremath{-}1)}^{2}}{{({2\mathcal{O}}{\mathcal{O}})}^{3}}$. As $\mathcal{O}$ increases, the coefficient of ${\ensuremath{\epsilon}}_{\mathcal{O}}^{2}$ rapidly becomes very small, varying as ${2}^{\ensuremath{-}6\mathcal{O}}$ for $\mathcal{O}$ large. In the limit of large $n$, ${\ensuremath{\eta}}_{\mathcal{O}}$ for odd order points approaches a constant and, for even order points, is proportional to $\frac{1}{n}$.
Sexuality-Related Outcomes of Adolescent Children of Teen Mothers

ABSTRACT The relationship between being an adolescent child of a teen mother and sexuality-related outcomes was investigated using data from the National Longitudinal Survey of Youth. Adolescents whose mothers were teenagers at first birth were more likely to have had sex by age 16 than other adolescents. Gender moderated this effect, as this relationship was stronger for sons than for daughters. In addition, children of mothers with a lower level of education, adolescents who lived in poverty, and adolescents who resided with less than two biological parents at the start of the study were more likely to have had sex.
Control System Design for the Digitized Grumman F - 14 Benchmark Control Problem

A particular H? design approach is coupled with multicriterion optimization to design a pitch axis controller for the F - 14, one of the CSS benchmark control problems. In this two-degree-of-freedom structure, the controller is designed via an H? method based on minimizing a weighted quadratic combination of the sensitivity and complementary sensitivity functions of the system. The pre-compensator is used to shape the output responses so as to cause the entire system to achieve the desired performance. The angle-of-attack ?(t) model following error, constraints on the normalized pitch rate |q(jw)| nom , and the effects of the wind gust and sensor noise on ? and q are examined. The robustness of ?(t) under the aircraft large parameter variations is also studied.
Full-Length Synaptonemal Complex Grows Continuously during Meiotic Prophase in Budding Yeast

The synaptonemal complex (SC) links two meiotic prophase chromosomal events: homolog pairing and crossover recombination. SC formation involves the multimeric assembly of coiled-coil proteins (Zip1 in budding yeast) at the interface of aligned homologous chromosomes. However, SC assembly is indifferent to homology and thus is normally regulated such that it occurs only subsequent to homology recognition. Assembled SC structurally interfaces with and influences the level and distribution of interhomolog crossover recombination events. Despite its involvement in dynamic chromosome behaviors such as homolog pairing and recombination, the extent to which SC, once installed, acts as an irreversible tether or maintains the capacity to remodel is not clear. Experiments presented here reveal insight into the dynamics of the full-length SC in budding yeast meiotic cells. We demonstrate that Zip1 continually incorporates into previously assembled synaptonemal complex during meiotic prophase. Moreover, post-synapsis Zip1 incorporation is sufficient to rescue the sporulation defect triggered by SCs built with a mutant version of Zip1, Zip1-4LA. Post-synapsis Zip1 incorporation occurs initially with a non-uniform spatial distribution, predominantly associated with Zip3, a component of the synapsis initiation complex that is presumed to mark a subset of crossover sites. A non-uniform dynamic architecture of the SC is observed independently of (i) synapsis initiation components, (ii) the Pch2 and Pph3 proteins that have been linked to Zip1 regulation, and (iii) the presence of a homolog. Finally, the rate of SC assembly and SC central region size increase in proportion to Zip1 copy number; this and other observations suggest that Zip1 does not exit the SC structure to the same extent that it enters. Our observations suggest that, after full-length assembly, SC central region exhibits little global turnover but maintains differential assembly dynamics at sites whose distribution is patterned by a recombination landscape.
Modeling of the vertebrate visual system. II. Application to the turtle cone retina.

Abstract The model of the vertebrate cone retina was adapted to the turtle retina with its red cone- and L-channel-dominances. The model consists of an ordering of four spatial organizations of unit hexagons, weighted inputs for all cones in the receptive fields, and linear polarization factors based on data from literature on turtle retina. Data generated by the model for spatial and chromatic patterns of receptive fields, intensity-response curves, dynamic ranges for cones, horizontal and bipolar cells proved remarkably consistent with literature. The model also generates observed phenomena such as near-field enhancement of cones due to stray light effects and electrical coupling of like-cones and far-field decrease in responses due to negative feedback from L-type horizontal cells to cones. Annular stimuli were shown to be more effective than spot stimuli for horizontal cells. The formal approach of the model demonstrates factors which play roles in various observed phenomena and all aspects of model can be displayed and tested both qualitatively and quantitatively.
Minimum-Weight Analysis of Anisotropic Plane-Fin Heat-Pipe Space Radiators

Equations are formulated for the two-dimensional, anisotropic conduction of heat in space radiator fins. The transverse temperature field is obtained by the integral method, and the axial field by numerical integration. A shape factor, defined for the heat-pipe interface boundary condition, simplifies the analysis and renders the results applicable to general heat-pipe/conduction-fin designs. The thermal results are summarized in terms of the fin efficiency, a fin length parameter, and a radiation/axial-conductance number. These relations, together with those for mass distribution between fins, heat pipes, and headers are used in formulating a radiator mass/heat-rate criterion function. Minimization of the criterion function results in asymptotic solutions for the optimum radiator geometry and conditions. The effect of physical properties on the optimum design is determined; in particular, performance is found to vary with fin conductivity to the 1/3 power for large conductivity values.
Laser thermal spectroscopy of highly granular NbN

The temperature dependence of far-infrared transmission gives $2\ensuremath{\Delta}(0)$, ${T}_{c}$, and evidence of fluctuations in NbN films. Homogeneous and highly granular (${R}_{\ensuremath{\square}}=21000 \ensuremath{\Omega}$) NbN are found to be equally strong coupled. BCS theory predicts a peak in transmission-versus-temperature curves which is observed at a reduced level in a homogeneous sample and vanishes completely in the granular material. The extinction of the peak is ascribed to zero-dimensional fluctuations near ${T}_{c}$.
Where did you put it? Issues in the design and use of a group memory

Collaborating teams of knowledge workers need a common repository in which to share information gathered by individuals or developed by the team. This is difficult to achieve in practice, because individual information access strategies break down with group information—people can generally find things that are on their own messy desks and file systems, but not on other people's. The design challenge in a group memory is thus to enable low-effort information sharing without reducing individuals' finding effectiveness. This paper presents the lessons from our design and initial use of a hypertext-based group memory, TeamInfo. We expose the serious cognitive obstacles to a shared information structure, discuss the uses and benefits we have experienced, address the effects of technology limitations and highlight some unexpected social work impacts of our group memory.
Phylogenetic analysis, genome evolution and the rate of gene gain in the Herpesviridae.

Abstract We used complete sequence data from 30 complete Herpesviridae genomes to investigate phylogenetic relationships and patterns of genome evolution. The approach was to identify orthologous gene clusters among taxa and to generate a genomic matrix of gene content. We identified 17 genes with homologs in all 30 taxa and concatenated a subset of 10 of these genes for phylogenetic inference. We also constructed phylogenetic trees on the basis of gene content data. The amino acid and gene content phylogenies were largely concordant, but the amino acid data had much higher internal support. We mapped gene gain events onto the phylogenetic tree by assuming that genes were gained only once during the evolution of herpesviruses. Thirty genes were inferred to be present in the ancestor of all herpesvirus, a number smaller than previously hypothesized. Few genes of recent origin within herpesviruses could be identified as originating from transfer between virus and vertebrate hosts. Inferred rates of gene gain were heterogeneous, with both taxonomic and temporal biases. Nonetheless, the average rate of gene gain was ∼3.5 × 10 −7 genes gained per year, which is an order of magnitude higher than the nucleotide mutation rate for these large DNA viruses.
Alcoholic liver disease may be prevented with adequate nutrients

Alcoholic liver disease is the result of a synergism between ethanol and nutritional factors. Therefore, it follows that the pathogenesis of alcoholic liver disease may be affected by the regulation of the intake of nutrients as well as by the regulation of the intake of ethanol.
Canine Hip Dysplasia: Pathogenesis, Diagnosis, and Genetic Control

(1998). Canine Hip Dysplasia: Pathogenesis, Diagnosis, and Genetic Control. Veterinary Quarterly: Vol. 20, Voorjaarsdagen Congress 1998, pp. S22-S24.
Nested data-parallelism on the gpu

Graphics processing units (GPUs) provide both memory bandwidth and arithmetic performance far greater than that available on CPUs but, because of their Single-Instruction-Multiple-Data (SIMD) architecture, they are hard to program. Most of the programs ported to GPUs thus far use traditional data-level parallelism, performing only operations that operate uniformly over vectors.NESL is a first-order functional language that was designed to allow programmers to write irregular-parallel programs - such as parallel divide-and-conquer algorithms - for wide-vector parallel computers. This paper presents our port of the NESL implementation to work on GPUs and provides empirical evidence that nested data-parallelism (NDP) on GPUs significantly outperforms CPU-based implementations and matches or beats newer GPU languages that support only flat parallelism. While our performance does not match that of hand-tuned CUDA programs, we argue that the notational conciseness of NESL is worth the loss in performance. This work provides the first language implementation that directly supports NDP on a GPU.
Evaluation of thin oxides grown by the atomic oxygen afterglow method

This paper discusses the basic electrical properties of thin, less than 200 A, films of silicon dioxide grown on silicon by a microwave plasma atomic oxygen afterglow method. This method of remote plasma oxidation of silicon allows gate oxides to be grown at temperatures as low as 400° C, and hence, is possibly attractive in VLSI/ULSI applications. Electrical properties of studied oxides depend strongly upon the composition of the discharge gas. The use of nitrogen as an oxygen diluent has an adverse impact on the fixed oxide charge density and dielectric strength. Superior oxide characteristics were obtained by adding hydrogen to the discharge gas particularly in the area of oxide breakdown statistics. Values of the intrinsic breakdown field in the range from 8 MV/ cm to 14 MV/cm were recorded in this case.
To generalize or not to generalize: spatial categories are influenced by physical attributes and language

The current work explored the conditions under which infants generalize spatial relationships from one event to another. English-learning 5-month-olds habituated to a tight- or loose-fit covering event dishabituated to a change in fit during a containment test event, but infants habituated to a visually similar occlusion event did not. Thus, infants’ responses appeared to be driven by the physical nature of the fit rather than visual similarity. This response pattern was replicated with Korean-speaking adults, but English-speaking adults showed no sensitivity to change in fit for either event. These findings suggest that language development links linguistic forms to universal, pre-existing representations of meaning, and that linguistic experience can shape sensitivity to distinctions that are marked in one’s native language.
Rotational Dynamics of Coumarin 153: Time-Dependent Friction, Dielectric Friction, and Other Nonhydrodynamic Effects

Subpicosecond fluorescence anisotropy measurements are used to characterize the rotational dynamics of coumarin 153 (C153) in 35 common solvents and eight solvent mixtures at room temperature. The rotational anisotropy decays of C153 are generally nonexponential as a result of the non-Markovian nature of the friction on its rotational motion. Rotational correlation times are observed to be larger in polar solvents than in nonpolar solvents of the same viscosity. This difference is examined in the context of theories of dielectric friction, which relate the extra friction in polar solute/solvent systems to long-range dipole -dipole interactions. Since the latter interactions have been thoroughly characterized via dynamic Stokes shift measurements for the same solute/solvent combinations studied here, the present data provide a unique opportunity to test general concepts of dielectric friction. Contrary to expectations, the departures from simple hydrodynamic behavior cannot be modeled using only theories of rotational dielectric friction. More important than dielectric friction is the role that the relative solute/solvent size plays in determining the extent of solute -solvent coupling. Once this size dependence is approximately accounted for, the remaining departures from simple hydrodynamic behavior are relatively small in all solvents. In polar aprotic solvents, solvation data indicate that dielectric friction effects should be rather modest (10-20% of the total friction). In these solvents no clear correlation is found between dielectric friction predictions and the observed solute -solvent coupling. However, in normal alcohol solvents the effects of dielectric friction are predicted to be large and well beyond the scatter in the experimental data. No evidence for such an important dielectric friction contribution is observed in these solvents, in spite of the fact that long-time components of the solvation dynamics do appear to be present in the rotational friction.
Localization and function of the electrical oscillation in electroreceptive ampullary epithelium from skates

A steady, spontaneous current oscillation (1 nA p-p) occurs in voltage-clamped, isolated ampullary organs (canal, ampulla, and nerve) from skates (Raja). Spectral analysis showed that energy in the oscillation was confined to a narrow band of frequencies (3 Hz) about a fundamental frequency (32 Hz at 20 degrees C) and in harmonics. The frequency of the oscillation was temperature dependent (increasing from 21 to 33 Hz for increases in temperature from 13 degrees C to 21 degrees C). The addition of 0.5 microM tetrodotoxin to the basal side of the ampullary epithelium eliminated afferent nerve activity but had no effect on the epithelial oscillation, indicating that the oscillation is not generated or induced by afferent nerve activity. Nitrendipine (2 microM) added to the solution bathing the basal side of the ampullary epithelium abolished the oscillation rapidly (within minutes), but a steady-state negative conductance (i.e., real part of the complex admittance
Predicting the Spinel–Nepheline Liquidus for Application to Nuclear Waste Glass Processing. Part II: Quasicrystalline Freezing Point Depression Model

The crystal-melt equilibria in complex 15-component-simulated high-level waste (HLW) glass melts are modeled based on quasicrystalline concepts that are discussed in Part I. A pseudobinary phase diagram between a transition metal ferrite spinel (an incongruent melt product of a transition metal iron-rich acmite) and nepheline is defined based on calculation of the quasicrystalline melt precursors calculated by a freezing point depression approach. The pseudobinary lies within the Al2O3–Fe2O3–Na2O–SiO2 quaternary system that defines the crystallization of basalt glass melts. The modeling provides the partitioning of species between the melt and the primary liquidus phases. The medium-range order of the melt and the melt-crystal exchange equilibria are defined based on a constrained mathematical treatment that considers the crystallochemical coordination of the elemental species in acmite and nepheline. The liquidus phases that form are shown to be governed by the melt polymerization (Part II) and the thermodynamic octahedral site preference energies (Part I). The liquidus model developed based on these concepts has been used to prevent unwanted crystallization in the world's largest HLW melter for the past 4 years while allowing >10 wt% higher waste loadings to be processed.
Tetracycline fluorescence as calcium-probe for nerve membrane with some model studies using erythrocyte ghosts

The tetracycline dyes, particularly chlorotetracycline, have been employed as probes of membrane-associated calcium during the excitation process of nerve. Both squid giant axons, stained internally, and lobster nerves, stained externally, show a small increase in fluorescent light during the action potential. Increasing the calcium concentration bathing a lobster nerve leads to a larger optical signal. Adding fluoride ion to the inside of a squid axon, which might be expected to influence the internal calcium-ion concentration, also leads to a larger optical signal. Squid axons have been studied under conditions of voltage clamp and the hyperpolarizing response. Model studies were done with erythrocyte ghosts to clarify the influence of membranes and calcium on the fluores-cence of the tetracyclines. Chlorotetracycline may be monitoring calcium concentration associated with the inner surface of the nerve membrane.
Determination of sub-surface distributions of residual stresses by a holographic-hole drilling technique

A method is described for combining incremental hole drilling with holographic interferometry to determine the distribution of in-plane residual stresses as a function of depth below the surface. The computational foundation of the method is summarized. Results of experiments to check the ability of the method to determine two different sub-surface stress distributions are given. Utilizing the same hologram, the feasibility of obtaining results at greater depths by drilling a large hole directly over a preceding smaller one is demonstrated.