cssi/SciSciGPT-SciSciNet huggingface dataset:
Modeling the performance of direct-detection Doppler lidar systems including cloud and solar background variability

Previous modeling of the performance of spaceborne direct-detection Doppler lidar systems assumed extremely idealized atmospheric models. Here we develop a technique for modeling the performance of these systems in a more realistic atmosphere, based on actual airborne lidar observations. The resulting atmospheric model contains cloud and aerosol variability that is absent in other simulations of spaceborne Doppler lidar instruments. To produce a realistic simulation of daytime performance, we include solar radiance values that are based on actual measurements and are allowed to vary as the viewing scene changes. Simulations are performed for two types of direct-detection Doppler lidar system: the double-edge and the multichannel techniques. Both systems were optimized to measure winds from Rayleigh backscatter at 355 nm. Simulations show that the measurement uncertainty during daytime is degraded by only approximately 10–20% compared with nighttime performance, provided that a proper solar filter is included in the instrument design.
Bereavement support groups for the elderly: Characteristics of potential participants

Abstract At the conclusion of a two-year longitudinal study of bereavement, 138 elderly persons were asked about their willingness to participate in support groups. Forty-four percent (N = 61) reported that they would have liked to participate. These persons were compared with those who did not want to participate with respect to sociodemographic, health, social support and psychosocial characteristics measured at six time periods. Nonstatistical patterns of the bereavement process indicate that those who are most likely to participate are more likely than the others to have a confidant but with less availability, have higher depression, and have lower perceived coping abilities and life satisfaction. Those wanting an intervention were also slightly more likely to be younger (ages 50–69), higher educated, and currently employed. Gender, perceived stress, health and self-esteem, and several social support variables did not differ substantially between the two groups. Implications for planning bereavement s...
The misapplication of graph theory to electric networks

Graph theory offers a false and misleading model for an electric network, a tearable orthogonal structure possessing branches only, and no nodes or planes. The unnecessary introduction of nodes and an avalanche of meaningless matrices is a smoke screen to hide the use of tensors, whose appearance is imperative and inescapable. During their analysis, graph theorists must always necessarily return by some legerdemain to the correct tensorial branch theory, which however is camouflaged with a misfit graph terminology.
Effects of Feedback Frequency and Timing on Acquisition, Retention, and Transfer of Speech Skills in Acquired Apraxia of Speech.

Purpose Two studies examined speech skill learning in persons with apraxia of speech (AOS). Motor-learning research shows that delaying or reducing the frequency of feedback promotes retention and ...
Number and gestational age of prior preterm births does not modify the predictive value of a short cervix.

Abstract Objective This study was undertaken to determine whether the number and gestational age of prior preterm deliveries modifies the significance of endovaginal sonographic cervical length less than 25 mm for the prediction of recurrent preterm birth less than 35 weeks' gestation. Study design Secondary analysis of a multicenter, blinded, observational study. Endovaginal ultrasonographic examinations were scheduled at 2-week intervals between 16 and 23 weeks' gestation in singleton pregnancies of 181 gravid women with at least 1 prior spontaneous preterm birth between 16 and 32 weeks' gestation. Results The earliest prior preterm birth occurred before 23 weeks in 61 women and at 23.0 to 31 weeks in 115; 5 had missing gestational age data. Cervical length was not different between these 2 groups both at the initial scan (median 38 vs 37 mm, P =.54) and considering the shortest ever observed cervical length over the entire study period (median 30 vs 30 mm, P =.97). Cervical length less than 25 mm was associated with spontaneous preterm birth less than 35 weeks for both groups (positive predictive value 80% vs 71%, P >.99). There were 134 women with 1 prior preterm delivery (74%) and 47 with 2 or more. Cervical lengths were not different between these 2 groups at the initial scan (median 36.5 vs 37 mm, P =.52) or over the entire study period (median 30 vs 32 mm, P =.31). The positive predictive value of cervical length less than 25 mm for subsequent spontaneous premature birth was not significantly higher in gravid women with multiple prior preterm births (100% vs 73%, P >.99). Conclusion Neither the number nor the gestational age of prior preterm births modify the predictive value of a cervical length less than 25 mm at 16 to 19 weeks for recurrent spontaneous preterm birth.
Rasagiline: A second-generation monoamine oxidase type-B inhibitor for the treatment of Parkinson’s disease

Purpose. The pharmacology, pharmacokinetics, clinical efficacy, and safety of rasagiline are reviewed. Summary. Rasagiline is a novel, investigational propargylamine that irreversibly and selectively inhibits monoamine oxidase type B (MAO-B). Rasagiline demonstrates complete and selective inhibition of MAO-B and is at least five times more potent than selegiline. Unlike selegiline, which is metabolized to amphetamine derivatives, rasagiline is biotransformed to the nonamphetamine compound aminoindan. Clinical studies have revealed that rasagiline is associated with improved outcomes in patients with early Parkinson’s disease (PD) and also reduces “off” time in patients with moderate to advanced PD with motor fluctuations. Rasagiline is rapidly absorbed by the gastrointestinal tract and readily crosses the blood–brain barrier. The optimal therapeutic dosage is 0.5–1 mg administered orally once daily. Rasagiline appears to be well tolerated, although elderly patients may be more prone to treatment-emergent adverse cardiovascular and psychiatric effects. At the recommended therapeutic dosage of up to 1 mg once daily, tyramine restriction is unnecessary. In addition to MAO-B inhibition, rasagiline has demonstrated neuroprotective properties in experimental laboratory models. The mechanisms whereby rasagiline exerts neuroprotective effects are multifactorial and include upregulation of cellular antioxidant activity and antiapoptotic factors. Conclusion. Rasagiline is an investigational selective and irreversible inhibitor of MAO-B that has demonstrated efficacy and safety for the treatment of PD. Whether rasagiline is associated with clinically significant neuroprotection is the subject of ongoing clinical trials.
A skew /spl mu/ lower bound

Exploitation of the NP hard, mixed /spl mu/ problem structure provides a polynomial time algorithm that approximates /spl mu/ with usually reasonable answers. When the problem is extended to the skew /spl mu/ problem an extension of the existing method to the skew /spl mu/ formulation is required. The focus of this paper is to extend the /spl mu/ lower bound derivation to the skew /spl mu/ lower bound and show its direct computation by way of a power algorithm.
The Elimination of the Parallax in Satellite Theory

When the perturbation affecting a Keplerian motion is proportional tor−n (n≥3), a canonical transformation of Lie type will convert the system into one in which the perturbation is proportional tor−2. Because it removes parallactic factors, the transformation is called the elimination of the parallax.
Undergraduate research and complex problem solving: Understanding and translating such experiences to the classroom

There has been much criticism about undergraduate engineering education not focusing on authentic real-world contexts which are most often associated to ill-structured domains. Undergraduate research experience is one context which provides a strong basis for our students to learn essential problem solving skills. Yet, although such experiences enable engineering students to begin the practice of solving complex problems in authentic contexts, there is a lack of understanding of the nature of these research projects. To fill this gap, we conducted in-depth interviews with students and utilized qualitative data analytic methods in tandem with the Problem-based Learning theory to classify research projects. Initial findings indicate that the research projects tend to be highly complex, moderately structured, and very different from the course-based projects. These findings are important for educators looking to incorporate research-based PBL projects into the classroom.
High performance high-purity sol-gel derived carbon supercapacitors from renewable sources

Abstract In this study highly pure carbons synthesized using resorcinol furaldehyde catalyzed with hexamethylenetetramine (an amine base) are tested for supercapacitor electrodes. This synthesis is not only from all-organic renewable sources, but can also significantly increase the performance of the device by promoting adequate electric double layer formation. The electrochemical characterization shows an increase in the specific capacitance per unit of surface area that is 18% higher than that of commercial biomass carbons and their synthetic counterparts. The life of the capacitor is also extended to twice that of the commercial brand tested here and has increased power after cycling. The supercapacitors made from this synthesis have electric double layer characteristics as desired in some applications. The samples have been tested for composition using XPS, and their electrochemical performance was analyzed using galvanostatic measurements and complex capacitance and power derived from impedance spectroscopy.
Laparoscopy in infants and children

Laparoscopy has been performed in 60 infants and children over a 32-mo period. Indications included: the problem of possible appendicitis, chronic abdominal pain, possible regional enteritis, possible biliary atresia, and liver biopsy. Fifty-two per cent of patients were spared laparotomy, while in 32% the need for operation was established. There were 2 errors in diagnosis, 3 failures, and 1 complication. Laparoscopy is considered to be a safe, effective, and economical diagnostic procedure that deserves wider application in the pediatric patient.
Hippocrates: First-Do-No-Harm Detailed Placement

Physical synthesis optimizations and engineering change orders typically change the locations of cells, resize cells or add more cells to the design after global placement. Unfortunately, those changes usually lead to wirelength increases; thus another pass of optimizations to further improve wirelength, timing and routing congestion characteristics is required. Simple wirelength-driven detailed placement techniques could be useful in this scenario. While such techniques can help to reduce wirelength, ones without careful timing constraint considerations might degrade the timing characteristics (worst negative slack, total negative slack, etc) and/or introduce more electrical violations (exceeding maximum output load constraints and maximum input slew constraints). In this paper, we propose a new detailed placement paradigm, which use a set of pin-based timing and electrical constraints in detailed placement to prevent it from degrading timing or violating electrical constraints while reducing wire-length, thus dubbed as Hippocrates: FIRST-DO-NO-HARM optimizations. Our experimental results show great promises. By honoring these constraints, our detailed placement technique not only reduces total wirelength (TWL), but also significantly improves timing, achieving 37% better total negative slack (TNS).
Lineage-specific functions of Bcl-6 in immunity and inflammation are mediated by distinct biochemical mechanisms

The transcription factor Bcl-6 orchestrates germinal center (GC) reactions through its actions in B cells and T cells and regulates inflammatory signaling in macrophages. Here we found that genetic replacement with mutated Bcl6 encoding Bcl-6 that cannot bind corepressors to its BTB domain resulted in disruption of the formation of GCs and affinity maturation of immunoglobulins due to a defect in the proliferation and survival of B cells. In contrast, loss of function of the BTB domain had no effect on the differentiation and function of follicular helper T cells or that of other helper T cell subsets. Bcl6-null mice had a lethal inflammatory phenotype, whereas mice with a mutant BTB domain had normal healthy lives with no inflammation. The repression of inflammatory responses by Bcl-6 in macrophages was accordingly independent of the repressor function of the BTB domain. Bcl-6 thus mediates its actions through lineage-specific biochemical functions.
Histologic changes in the guinea pig gastrointestinal tract following 1 weeks' administration of chlorpromazine, haloperidol or atropine

A comparison was made between the toxic effects of chronic chlorpromazine, haloperidol or atropine on the guinea pig intestinal tract. Chlorpromazine, administered at a dose of 30 mg/kg/day, IP for 7 days, produced marked pathologic changes in the guinea pig cecum, consisting of inflammation, edema and hemorrhage. None of these effects were noted when haloperidol, 2 or 10 mg/kg/day or atropine 30 mg/kg/day were similarly administered. Similar toxic effects may occur in humans on long-term chlorpromazine or other phenothiazine therapy, thereby accounting for the paralytic ileus observed with these drugs.
Does Tree Hardness Influence Nest-Tree Selection by Primary Cavity Nesters?

Cavity-nesting birds that excavate nest holes may be limited by the availability of suitable substrates for excavation. Suitability of trees for excavation may be influenced by substrate hardness and excavation strength of the bird. Excavation strength, in turn, may vary among bird species, causing nest-tree selection to vary among excavator species. We examined use of quaking aspens (Populus tremuloides) for nest trees as a function of tree hardness in four species of woodpeckers: Williamson's Sapsucker (Sphyrapicus thyroideus), Red-naped Sapsucker (S. nuchalis), Downy Woodpecker (Picoides pubescens), and Hairy Woodpecker (P. villosus). Hardness of trees was measured at 95 nest trees, 94 neighboring trees, and 150 random trees using a new technique described here. Other investigators have speculated that the gross external appearance of trees/snags can be used to estimate hardness. Hardness decreased from live trees to partly dead trees to dead trees and with increasing height in trees, but hardness was not related to other external features such as numbers of conks or percentage of the tree covered with bark. All four bird species chose nest trees that were softer than neighboring or random trees, and nest trees were softer at nests than at other heights measured. The four species selected trees of different hardness for nesting; Red-naped Sapsucker and Hairy Woodpecker chose harder trees than Williamson's Sapsucker and Downy Woodpecker. These results suggest that primary cavity nesters are sensitive to subtle characteristics of trees that reflect hardness, some of which may not be apparent in the external appearance of the trees.
The visual field representation in striate cortex of the macaque monkey: Asymmetries, anisotropies, and individual variability

The topographic organization of striate cortex in the macaque was studied using physiological recording techniques. Results were displayed on two-dimensional maps of the cortex, which facilitated the quantitative analysis of various features of the visual representation. The representation was found to be asymmetric, with more cortex devoted to lower than to upper fields. Over much of striate cortex the representation is anisotropic. in that the magnification factor depends upon the direction along which it is measured. There is considerable individual variability in these features as well as in the overall size of striate cortex. Outside the fovea, the cortical representation shows only modest deviations from a logarithmic conformal mapping, in which the magnification factor is proportional to the inverse of eccentricity in the visual field. Comparison of receptive field size with cortical magnification was used to estimate the "point image size" in the cortex (i.e. the extent of cortex concerned with processing inputs from any given point in the visual field). Our evidence supports a previous report that point-image size varies significantly with eccentricity. This is of interest in relation to anatomical evidence that the dimensions of columnar systems in striate cortex are largely independent of eccentricity.
Will the Dollar be Dethroned as the Main Reserve Currency

The U.S. dollar was in the line of fire as leaders from the largest developed and developing countries participated in the G8 meeting in July, 2009. China and other emerging market heavyweights suc...
ULTRASTRUCTURE OF SELECTIVE CHLOROPLAST DESTRUCTION AFTER SOMATIC CELL FUSION IN GRIFFITHSIA PACIFICA KYLIN (RHODOPHYTA)

Fusion of somatic cells from different geographic isolates of Griffithsia pacifica is followed by a cytoplasmic incompatibility reaction (CIR)5 in the cytoplasm donated by only one of the isolates. This CIR is characterized by the aggregation, fusion, and lysis of chloroplasts of the sensitive strain; the cholorplasts of the other strain are unaffected. Within a given cell, chloroplast fusions result in a 50% decrease in chloroplast number in the first 8 h; over the next 3–5 weeks, chloroplast lysis leads to the complete loss of photosynthetic pigments (18). Results of this ultrastructural study indicated that the primary effect of the cytoplasmic incompatibility reaction was a directed destruction of the sensitive strain chloroplasts. No aggregation or abnormalities were seen in organelles other than the chloroplasts. Chloroplast destruction was accompanied by extensive vesiculation of the cytoplasm and a definit change in the physiological state of the cell; the dictyosomes became inactive and there was a reduction in the amount of endoplasmic reticulum, cytoplasmic ribosomes and starch grains. This selective destruction of one chloroplast population in the presence of a second population of unaffected chloroplasts suggests that the incompatibility reaction observed in G. pacifica results from competitive interactions between the two chloroplast types.
X-Ray Photoemission Valence-Band Spectra and Theoretical Valence-Band Densities of States for Ge, GaAs, and ZnSe

Author(s): Pollak, R.A.; Ley, L.; Kowalczyk, S.; Shirley, D.A.; Joannopoulos, J.D.; Ghadi, D.J.; Cohen, Marvin L.
In vivo stimulation of H-2Dd expression following RadLV infection of thymocytes: increased transcription and DNA-binding activity to sequences 5' of the Dd gene

Abstract Early studies showed that resistance to RadLV-induced leukaemia is mediated by gene(s) in the H -2 D region of the MHC. Furthermore, these experiments correlated disease resistance with changes in H-2 expression occurring very early after virus inoculation. In the present study, we have begun to study at the molecular level this stimulation of H-2D d class I expression in thymocytes of resistant mouse strains following infection by RadLV. The resistant strain of B10.T(6R) mice is used in these studies. When these infected thymocytes are assayed by fluorescence-activated cell sorting analysis, we can detect increased levels of H -2 D d expression on the surface of the thymocytes as early as 12 days following intrathymic injection of RadLV. RNA was prepared and examined by Northern blot analysis; H-2 mRNA levels are shown to be elevated on the order of four-fold. Nuclei were prepared from normal and infected thymocytes and the run-off transcripts were analysed by slot-blot hybridization. The rate of H-2 mRNA transcription is shown to be two- to three-fold higher in RadLV-infected thymocytes at 14 days post-infection when compared to that of normal thymocytes. These data demonstrate that elevation of H-2 surface expression following RadLV infection is the result of transcriptional activation. Extracts have been prepared from both normal and infected B10.T(6R) thymocytes and have been used in gel mobility assays in order to detect the interaction of potential trans -acting regulatory factors with sequences 5′ of the H -2 D d gene. Specific binding occurs in both extracts, but the assay shows that the extracts differ both quantitatively and qualitatively; the extracts from infected thymocytes bind to additional sequences and to a higher degree than that from normal thymocytes. DNase I protection analysis locates a number of protein-binding sites, some of which are protected by extracts of either origin and some of which are only protected by extracts from infected cells. Two of these sequences are similar to the previously recognized consensus recognition sequences for the binding of AP-1 and NF-χB. Oligonucleotides have been synthesis
Case Method for Teaching Water-Resources Management

The case-study method can enrich water-resources–management education. The status of graduate education in water-resources management is summarized, the use of case studies in business and public-administration education is described, and examples of case studies in water-resources management are given. Experience with using case studies at Colorado State University is described. The cases raise student interest levels, show how decision support systems influence decision processes, and give students a sense of participation in real-world political situations. Programs seeking to use case studies can increase experience-based problem-solving techniques and integrate material from relevant discipline areas. More and better case studies are needed. Experience in the case study method might be extended to infrastructure and environmental education.
Using the Professional Resources in Nutrition Sciences (PRINS) Web Site

Abstract The web site, Professional Resources in Nutrition Sciences (PRINS), was developed in the fall of 1998 to provide access to Internet/World Wide Web resources useful to dietetic and nutrition professionals and students. PRINS is a professional rather than consumer-oriented resource, with nearly 2,000 links to information pertaining to the profession. The nutrition-related web sites include: national and state credentialing agencies; job web sites and search engines; mailing list and bulletin board services; nutrition-related organizations on a global scale; professional associations; and professional preparation programs. Other resources include online publications, instructional materials, and software. Key features of PRINS will be showcased, with instructions on how to use the web site effectively for research, networking, career development, and job searching. Also, instructions on how to use PRINS in professional preparation programs to introduce students to the nutrition profession and upon graduation find dietetic internships and jobs. (http://academic.brooklyn.cuny.edu/hns/prins)
Accurate intensity measurements for proton beams with a 201 MHz structure

A counting system which measures the absolute beam intensity accurately (< 1%) at intermediate energies with a beam microstructure of 201.25 MHz or lower is described in this paper. The number of beam micropulses containing one or more beam particles are counted and time-sequenced coincidences between micropulses correct this number to obtain the actual number of beam particles using formulas based on Poisson statistics. The counting system, both the experimental setup and the correction method, was examined fully with two different beam microstructures. 10 MHz and 201.25 MHz, the two main beam microstructures at LAMPF. Maximum beam intensities, below which the system is accurate within a few tenths of a percent, were determined to be ∼ 0/4 pA and ∼ 0.1 pA average beam currents for the 5 ns and 100 ns beam microstructures, respectively.
BOUND WATER DETERMINATION USING VACUUM DIFFERENTIAL SCANNING CALORIMETRY

SUMMARY– Using a vacuum differential scanning calorimeter, it was possible to measure the relative bound water content of several food stuffs. Freeze-dried beef powder, freeze-dried whole egg powder, modified corn starch powder and non-fat dry milk were used. Results indicate that the relative bound water of food stuffs can be determined, but determination of total water from water binding energy will require further experimentation.
L1 Adaptive Control for a Class of Nonaffine-in-Control Nonlinear Systems

Abstract This paper presents an L 1 adaptive controller for a class of nonlinear systems, nonaffine in control. As compared to previous L 1 architectures for nonaffine-in-control systems, the solution discussed in this paper admits a broader class of nonlinear systems by relaxing some of the (restrictive) assumptions previously made. We also consider a more general filtering structure with which we are able to improve performance and robustness of the closed-loop system, compared to prior results of L 1 adaptive control for nonaffine-in-control systems.
Temporal processing in deaf signers

Abstract The auditory and visual modalities differ in their capacities for temporal analysis, and speech relies on more rapid temporal contrasts than does sign language. We examined whether congenitally deaf signers show enhanced or diminished capacities for processing rapidly varying visual signals in light of the differences in sensory and language experience of deaf and hearing individuals. Four experiments compared rapid temporal analysis in deaf signers and hearing subjects at three different levels: sensation, perception, and memory. Experiment 1 measured critical flicker frequency thresholds and Experiment 2, two-point thresholds to a flashing light. Experiments 3–4 investigated perception and memory for the temporal order of rapidly varying nonlinguistic visual forms. In contrast to certain previous studies, specifically those investigating the effects of short-term sensory deprivation, no significant differences between deaf and hearing subjects were found at any level. Deaf signers do not show diminished capacities for rapid temporal analysis, in comparison to hearing individuals. The data also suggest that the deficits in rapid temporal analysis reported previously for children with developmental language delay cannot be attributed to lack of experience with speech processing and production.
Requirement for GLY-60 of Escherichia coli adenylyl cyclase for ATP binding and catalytic activity.

Abstract The region of Escherichia coli adenylyl cyclase spanned by glycine-55 to threonine-65 was tested for its importance for enzyme activity. Site-directed mutagenesis was used to replace glycine-55 and glycine-60 as well as lysine-59, leucine-63 and threonine-65 with other amino acids. While substitution of glycine-55 with aspartic acid produced no significant change in kinetic parameters, the change of glycine-60 to aspartic acid or asparagine eliminated binding to 8-azido-ATP and decreased the Vmax (two orders of magnitude) and Km (factor of four-five). Smaller effects on kinetic parameters were observed with substitutions of lysine-59, leucine-63 or threonine-65.
Amyotrophic lateral sclerosis immunoglobulins increase Ca2+ currents in a motoneuron cell line

The sporadic form of amyotrophic lateral sclerosis (ALS) is an idiopathic and eventually lethal disorder causing progressive degeneration of cortical and spinal motoneurons. Recent studies have shown that the majority of patients with sporadic ALS have serum antibodies that bind to purified L-type voltage-gated calcium channels and that antibody titer correlates with the rate of disease progression. Furthermore, antibodies purified from ALS patient sera have been found to alter the physiologic function of voltage-gated calcium channels in nonmotoneuron cell types. Using whole-cell patch-clamp techniques, immunoglobulins purified from sera of 5 of 6 patients with sporadic ALS are now shown to increase calcium currents in a hybrid motoneuron cell line, VSC4.1. These calcium currents are blocked by the polyamine funnel-web spider toxin FTX, which has previously been shown to block Ca2+ currents and evoked transmitter release at mammalian motoneuron terminals. These data provide additional evidence linking ALS to an autoimmune process and suggest that antibody-induced increases in calcium entry through voltage-gated calcium channels may occur in motoneurons in this disease, with possible deleterious effects in susceptible neurons.
Clicking instead of walking: Consumers searching for information in the electronic marketplace

L'article compare le cout de la recherche d'information dans les environnements en ligne et physique. Il etudie egalement les effets des facteurs personnels et des variables du systeme sur le nombre de sites web visites et le temps passe sur chaque site. Le marche en ligne a transforme les consommateurs en utilisateurs d'ordinateur, remplacant l'effort physique par un effort cognitif qui peut empecher de rechercher davantage d'information.
Transposable elements and an epigenetic basis for punctuated equilibria

Evolution is frequently concentrated in bursts of rapid morphological change and speciation followed by long-term stasis. We propose that this pattern of punctuated equilibria results from an evolutionary tug-of-war between host genomes and transposable elements (TEs) mediated through the epigenome. According to this hypothesis, epigenetic regulatory mechanisms (RNA interference, DNA methylation and histone modifications) maintain stasis by suppressing TE mobilization. However, physiological stress, induced by climate change or invasion of new habitats, disrupts epigenetic regulation and unleashes TEs. With their capacity to drive non-adaptive host evolution, mobilized TEs can restructure the genome and displace populations from adaptive peaks, thus providing an escape from stasis and generating genetic innovations required for rapid diversification. This "epi-transposon hypothesis" can not only explain macroevolutionary tempo and mode, but may also resolve other long-standing controversies, such as Wright's shifting balance theory, Mayr's peripheral isolates model, and McClintock's view of genome restructuring as an adaptive response to challenge.
Predictive distributions in risk analysis and estimation for the triangular distribution

Many Monte Carlo simulation studies have been done in the field of risk analysis. This article demonstrates the importance of using predictive distributions (the estimated distributions of the explanatory variable accounting for uncertainty in point estimation of parameters) in the simulations. We explore different types of predictive distributions for the normal distribution, the lognormal distribution and the triangular distribution. The triangular distribution poses particular problems, and we found that estimation using quantile least squares was preferable to maximum likelihood. Copyright © 2001 John Wiley & Sons, Ltd.
Quantitative autoradiographic analysis of D1 and D2 dopamine receptors in rat brain in early and late pregnancy.

Abstract This study examined the levels of D 1 and D 2 dopamine receptors in the rat brain during pregnancy, a physiologically unique and important naturally occurring state. We are particularly interested in changes in the dopamine receptor complement of the brain during pregnancy because these receptors might support some components of the immediate postpartum onset of normal maternal behavior. Quantitative in vitro receptor autoradiography was applied particularly focusing on brain areas that control maternal behavior. The D 1 dopamine receptor selective antagonist [ 3 H]SCH23390 and the D 2 dopamine receptor selective antagonist [ 3 H]spiperone were used as the ligands. We examined the levels of binding to D 1 and D 2 dopamine receptors in brains in females on day 2 (early pregnancy) and day 21 (late, but prepartum pregnancy) of pregnancy. In addition, brains from females on diestrus-1 and from males provided reference points to the existing literature. Late in pregnancy females had significantly 18–27% lower levels of binding to D 1 dopamine receptors in the lateral striatum, the medial striatum, and the nucleus accumbens when compared to all other groups. Late in pregnancy, females had also significantly 11–25% lower levels of binding to D 2 dopamine receptors in the lateral striatum, the anterior striatum, the nucleus accumbens and the olfactory tubercle compared to all other experimental groups. We examined all of the brain regions already established to be important for maternal behavior, and found that dopamine receptor binding changed across pregnancy only in one such region, the nucleus accumbens. Thus pregnancy, perhaps the hormones of pregnancy, reduces the levels of D 1 and D 2 dopamine receptors in the striatum, and the nucleus accumbens, but not in other brain regions.
AGE-RELATED VASCULAR EFFECTS OF PROSTAGLANDIN D 2 (PGD 2 )

Top of pageAbstract PGD2 infusions decrease mean pulmonary arterial pressure (Ppa) and resistence (PVR) in both fetal and hypoxic, neonatal lambs, yet cause direct pulmonary constriction in hypoxic juveniles. We gave bolus PGD2 to 19 acutely-operated lambs, 4-24 days old(d). Normoxic lambs were given 1 and 10 μg/kg with recovery time between doses. The lambs were then ventilated with 13% O2 and given the same doses of PGD2. We compared % Δ of Ppa, mean systemic arterial pressure (Pas), and PVR in lambs <7d and ≥14d. In normoxic lambs, 1 μg/kg had no effect on Ppa and PVR at <7d but caused significant increases in ≥14d animals. Ten μg/kg raised Ppa and PVR in both younger and older normoxic lambs. In hypoxic animals, both doses lowered Ppa and PVR in the <7d group, while in the ≥14d lambs there was little or no pulmonary effect. Pas was significantly increased by PGD2 in all groups at both doses. We conclude that the pulmonary vasodilator effect of PGD2 in hypoxic neonatal lambs decreases with advancing postnatal age, and that by 14 days, PGD2 is no longer an effective pulmonary vasodilator.
Competing Risks and Burn Outcomes: More Questions Than Answers

Age, total body surface area of burn injury, and inhalation injury have long been documented as independent predictors of mortality in burn injury1; all these factors are identifiable on admission. In this issue, Taylor et al2 propose the use of competing risk analysis to examinedynamic factors that may affect lengthof stay andmortality in patientswith burns. Although thismethod isnew inpatientswithburns, itwas initially applied in a large cohort of patients with trauma more than adecade ago.3Modeling outcomes in patientswith complexconditions, suchasburnsandtrauma, is inherently fraught with challenges. The key assumptionunderlying theuse of competing risk analysis is that the causes of early and late mortality are different in patients with burns as they are in patients with trauma.4Theauthors includea singleparagraphwith a simple univariate description of patients who died within 1 day of admission. Does this description provide a complete picture of patients who have early deaths following burn injury, or is thepicturemore complicated than the total body surface area of larger burn injuries and greater incidence of inhalation injury? Could depth of burns also play a role? Presumably, the 24-hour cutoff is designed to capturepatientsplacedontopalliative care early; while National Burn Repository data do not include this information, do patients for whom the decision to start palliative care is later lookmore similar topatientswho die early, or more similar to patients who die later? A trend analysishighlightingpractice changes through theyears could be developedusing the included 9 years of data andwould allowus toanswer theexceptionally importantquestion—arewe getting better at the care of patients with burns? Theuseofcompeting riskanalysismarksan importantnew way for us to consider outcomes in patients with burns. Ultimately, however, this analysis results in as many—or more— questions than answers.
Calculations of Exchange Bias in Thin Films with Ferromagnetic/Antiferromagnetic Interfaces

A microscopic explanation of exchange bias in thin films with compensated ferro/antiferromagnetic interfaces is presented. Full micromagnetic calculations show the interfacial exchange coupling to be relatively strong with a perpendicular orientation between the ferro/antiferromagnetic axis directions, similar to the classic ``spin-flop'' state in bulk antiferromagnets. With reasonable parameters the calculations predict bias fields comparable to those observed and provide a possible explanation for both anomalous high field rotational hysteresis and recently discovered ``positive'' exchange bias.
The Atrioventricular Node, his Bundle and Bundle Branches-a New Histologic Technique

A technique for examination of the conducting system of the heart is described. A block of tissue embracing the ostium of the coronary sinus, the pars membranacea, the septal leaflet of the tricuspid valve, and appropriate amounts of interatrial and interventricular septum is flattened and fixed in a Kaiserling I solution. Blocks are subsequently cleared in methyl salicylate and trimmed. Sections are cut from the blocks after paraffin embedding beginning from the endocardial surfaces of the right heart chambers. The sections are mounted and stained on 35 mm unperforated leader film and covered with an acrylic preservative. For examination of the conducting system many fewer sections are required than with previous techniques.
The Action of DNA Ligase at Abasic Sites in DNA

Apurinic/apyrimidinic (AP) sites occur frequently in DNA as a result of spontaneous base loss or following removal of a damaged base by a DNA glycosylase. The action of many AP endonuclease enzymes at abasic sites in DNA leaves a 5′-deoxyribose phosphate (dRP) residue that must be removed during the base excision repair process. This 5′-dRP group may be removed by AP lyase enzymes that employ a β-elimination mechanism. This β-elimination reaction typically involves a transient Schiff base intermediate that can react with sodium borohydride to trap the DNA-enzyme complex. With the use of this assay as well as direct 5′-dRP group release assays, we show that T4 DNA ligase, a representative ATP-dependent DNA ligase, contains AP lyase activity. The AP lyase activity of T4 DNA ligase is inhibited in the presence of ATP, suggesting that the adenylated lysine residue is part of the active site for both the ligase and lyase activities. A model is proposed whereby the AP lyase activity of DNA ligase may contribute to the repair of abasic sites in DNA.
Abstract C194: In vivo characterization of AMG 900, an orally active small molecule inhibitor of aurora kinases in phase 1 clinical trials

Background: The aurora family of serine‐threonine kinases (Aurora‐A, ‐B, ‐C) regulate cell‐cycle progression in mammalian cells. Aurora kinases A and B are essential for proper chromosome congression, segregation, and cytokinesis during mitosis, whereas aurora kinase C function appears restricted to male meiosis. Aurora kinase B is responsible for the direct phosphorylation of histone H3 on serine‐10 (p‐histone H3). Aurora kinase A and B expression is elevated in a variety of human cancers and is associated with advanced clinical staging and poor prognosis. The emergence of aurora kinases as key mitotic regulators and their potential role in tumorigenesis has focused substantial interest in developing selective small molecule inhibitors for the treatment of human cancers. Objective: The aim of this study was to characterize the in vitro effects of AMG 900 in tumor cell lines, including cell lines resistant to paclitaxel and three well‐characterized aurora kinase inhibitors. Results: AMG 900 is a novel ATP competitive small molecule inhibitor that is highly potent and selective for aurora kinases A, B, and C. In cells, AMG 900 inhibits autophosphorylation of aurora kinases A and B as well as the phosphorylation of histone H3. The predominant cellular response of tumor cells to AMG 900 treatment is aborted cell division without a mitotic arrest, which leads to endoreduplication and cell death. The effect of AMG 900 was tested in a panel of 26 tumor cell lines to evaluate its potential to inhibit cell proliferation across multiple tumor types. AMG 900 inhibited the proliferation of tumor cell lines at low nanomolar concentrations (EC50 values 1–6 nM). Importantly, AMG 900 was equally potent against multidrugresistant (MDR) cell lines expressing ATP‐binding cassette transporters (P‐gp and BCRP1), whereas paclitaxel and three aurora kinase inhibitors (AZD1152, MK‐0457, and PHA‐739358) showed a loss of potency in these MDR‐positive cell lines compared with matched parental cell lines. To further investigate potential mechanisms of resistance, an HCT116 cell line was adapted to grow in the presence of AZD1152, a selective inhibitor of aurora kinase B. The resulting AZD1152‐resistant HCT116 subline harbors a mutation in one allele of the aurora kinase B gene (W221L substitution) and was negative for P‐gp and BCRP1 expression. AMG 900 induced an accumulation of cells with ≥4N DNA content (EC50 value 5 nM) and inhibited colony formation in this AZD1152‐resistant HCT116 subline. Conclusion: To our knowledge, AMG 900 is the first described inhibitor of aurora kinases A, B, and C that has uniform in vitro potency in MDR‐positive tumor cell lines. AMG 900 is currently undergoing phase 1 clinical evaluation in patients with advanced solid tumors. Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A261.
Velocity measurements in the free convection flow above a heated horizontal cylinder

Abstract The fluid dynamics of the free convection water flow above a heated horizontal cylinder were investigated using particle image velocimetry. Velocity measurements were obtained in three orthogonal planes, with each plane acquired independently in time. The experiment was performed for a Rayleigh number of 1.33 × 10 6 and for water heights above the cylinder surface of H / D = 1, 2, 4, 6, 8, and 12. The top water surface was open to room air, and the height of the free surface introduced different effects of vertical confinement. For all water heights studied, the plume above the cylinder and its interaction with the free surface were observed. For water heights of H / D = 4 and 6, the appearance of a swaying motion was captured in the plane perpendicular to the cylinder axis, and a meandering motion was detected in the other two orthogonal planes. A vortex was observed to form alongside of the plume and rise to the free surface, where it detached from the plume structure and moved along the free surface. Vortex dynamics and the physical characteristics of the swaying and meandering motions appeared to be interdependent, providing a possible relation between vortex formation, swaying, and meandering. Comparisons with previous analytical and experimental results highlight the complicated three-dimensional flow structure that governs heat transfer from the cylinder.
Photoelectric counting measurements as a test for the existence of photons

It is pointed out that it is impossible to distinguish between photons and classical wave packets by measurement of photoelectric counting statistics for any state of a light beam for which a classical description exists. Therefore, an experiment with a thermal light source recently proposed by Karp as a test for the existence of photons can yield no information on this question, even if it should be able to distinguish between two different statistical models of a light beam. The quantum nature of the optical field can, however, be inferred from other photoelectric measurements, some of which are briefly discussed.
The roles of companions in geriatric patient–interdisciplinary oncology team interactions

Abstract This study examined companions' roles in interactions between patients and interdisciplinary geriatric oncology team members. Companions' roles identified include memory aid, emotional support, transcriber, aid in decision making, companionship, elaboration, advocate for patient, and interpreter. Specific patterns of variability of roles across team member disciplines include relatively passive companions who performed more active roles with physician, relatively active companions who performed more passive roles with physician, and relatively passive companions who performed more active roles when particular topics were raised, regardless of team discipline. Two patterns of stability across interactions emerged: consistently active or passive.
The media and public opinion on genetics and biotechnology: mirrors, windows, or walls?

Arguments regarding the relationship between media discourse and public opinion have raged for decades, if not centuries. COmparing media coverage of biotechnology between 1992 and 2001 in two national newspapers with national survey data collected in early 2003, an argument is made that a general one-dimensional media effect is not occurring within the US public regarding media discourse. Given the multivalent characteristics of the media and the interpretive filters used by audiences - including ignoring information - even strong slants by the presumed opinion-leading press (the New York Times and the Washington Post) do not predict public opinion on a nascent issue such as biotechnology. While some observations show these mirrors to be ephemeral.
Effects of “hypophysectomy” by surgical decapitation on histochemically demonstrable peroxidase activity in the thyroid gland of the developing chick embryo

The effects of “hypophysectomy” by means of surgical decapitation upon histochemically demonstrable peroxidase activity in the thyroid glands of developing chick embryos has been studied from 5.5- to 18.5-days of incubation. “Hypophysectomy” results in subnormal levels of histochemically demonstrable peroxidase activity in the embryonic thyroid gland from day 10.5 to day 18.5 of incubation. Activity of this enzyme is not apparent prior to day 6.5 of incubation in the intact chick embryo. A single administration of TSH to the embryo at this time does not affect the initial appearance of peroxidase activity in the embryonic chick thyroid gland. Administration of TSH on days 11.5 through 13.5 to hypophyseoprivic embryos results in normal levels of peroxidase activity in the chick embryo thyroid gland. The data suggest that the pars distalis-thyroid axis is established on or about day 10.5 of incubation in the chick embryo. The data further suggest that the amounts of peroxidase activity present in embryonic chick thyroids are directly or indirectly dependent upon adenohypophysial activity starting at about this time.
Can traumatic stress alter the brain? Understanding the implications of early trauma on brain development and learning

Abstract Background Youth who experience traumatic stress and develop post-traumatic symptoms secrete higher levels of the glucocorticoid cortisol than youth with no trauma history. Animal research suggests that excess corticosterone secretion can lead to neurotoxicity in areas of the brain rich in glucocorticoid receptors such as the hippocampus and the prefrontal cortex (PFC). These two areas of the brain are involved in memory processing and executive function, both critical functions of learning. Methods In this article, we summarize findings presented at the National Summit for Stress and the Brain conducted at Johns Hopkins University's Department of Public Health in April 2011. The presentation highlighted structural and functional imaging findings in the hippocampus and PFC of youth with post-traumatic stress symptoms (PTSS). Results Youth with PTSS have higher levels of cortisol. Prebedtime cortisol levels predict decreases in hippocampal volume longitudinally. Cortisol levels are negatively correlated with volume in the PFC. Functional imaging studies demonstrate reduced hippocampal and PFC activities on tasks of memory and executive function in youth with PTSS when compared with control subjects. Conclusions Effective interventions for youth with PTSS should target improved function of frontolimbic networks. Treatment outcome research using these potential markers can help develop more focused interventions that target the impaired learning of vulnerable youth experiencing traumatic stress.