cssi/SciSciGPT-SciSciNet huggingface dataset:
On an unusual means by which the sessile marine ciliate folliculina simplex maintains its widespread geographical distribution

The sessile protozoan Folliculina simplex Dons is found attached to the shells of large teleplanic gastropod veliger larvae exceeding 4 mm in length. Planktonic prosobranch veligers found bearing folliculinids include Tonna galea (Linne), Charonia variegata (Lamarck), Cymatium parthenopeum (von Salis), Cymatium nicobaricum (Roding), and Bursa thomae (Orbigny). From a total of 934 plankton samples taken in the north and tropical Atlantic Ocean and adjacent seas, 12.1 percent contained gastropod veligers which bore Folliculina simplex on their shells. Dispersal on the shells of pelagic gastropod larvae presents one singular means by which Folliculina simplex maintains its wide geographic range.
Understanding cellular leiomyomas: a case-control study.

Objective Reports exist in which cellular leiomyomas (CLs) appear to have clinical characteristics or genetic profiles similar to leiomyosarcomas. This study aimed to determine whether most CLs differ clinically from typical uterine leiomyomas (ULs). Study Design A case-control study was conducted with women who underwent surgical procedures between January 1989 and December 2008 and who were diagnosed with a CL (n = 99). Control subjects, who were matched in a 2:1 ratio, were women with a diagnosis of UL (n = 198). Hospital and ambulatory records were reviewed. Results In multivariable logistic regression analyses, women with CLs were more likely to have surgery for the indication of enlarging leiomyoma and less likely to have concomitant endometriosis or adenomyosis. Uteri that contained CLs were also more likely to have larger and fewer leiomyomas when compared with control subjects. Conclusion CLs have a distinct clinical phenotype compared with ULs and have some characteristics in common with leiomyosarcomas.
Development of a Boundary Layer Property Interpolation Tool in Support of Orbiter Return To Flight

A new tool was developed to predict the boundary layer quantities required by several physics-based predictive/analytic methods that assess damaged Orbiter tile. This new tool, the Boundary Layer Property Prediction (BLPROP) tool, supplies boundary layer values used in correlations that determine boundary layer transition onset and surface heating-rate augmentation/attenuation factors inside tile gouges (i.e. cavities). BLPROP interpolates through a database of computed solutions and provides boundary layer and wall data (delta, theta, Re(sub theta)/M(sub e), Re(sub theta)/M(sub e), Re(sub theta), P(sub w), and q(sub w)) based on user input surface location and free stream conditions. Surface locations are limited to the Orbiter s windward surface. Constructed using predictions from an inviscid w/boundary-layer method and benchmark viscous CFD, the computed database covers the hypersonic continuum flight regime based on two reference flight trajectories. First-order one-dimensional Lagrange interpolation accounts for Mach number and angle-of-attack variations, whereas non-dimensional normalization accounts for differences between the reference and input Reynolds number. Employing the same computational methods used to construct the database, solutions at other trajectory points taken from previous STS flights were computed: these results validate the BLPROP algorithm. Percentage differences between interpolated and computed values are presented and are used to establish the level of uncertainty of the new tool.
Resonant two-photon absorption and emission in single-crystal thin films of CuCl

Abstract A comparative study of the luminescence and absorption spectra of excitonic molecules in thin films of cuprous chloride grown on sodium chloride and fused quartz is reported. Thin films of CuCl on NaCl are in single-crystalline form while CuCl on quartz are polycrystalline as evidenced by X-ray diffraction analysis. Under resonant excitation at 7 K, the two-photon absorption spectra for CuCl grown on NaCl exhibit a reduction in linewidth and an increase in the peak absorption as compared with those for CuCl grown on fused silica quartz. Also, the emission lines arising from the decay of excitonic molecules to exciton states are sharper in the single-crystal thin film. These results suggest that the recently grown CuCl single-crystal thin films are substantially superior to polycrystalline thin films for studies of picosecond biexcitonic optical bistability and Bose-condensation of excitonic molecules.
Microhardness, Structure, and Composition Study of Amorphous Hydrogenated Boron Carbide

We have grown amorphous hydrogenated boron carbide thin films by rf plasma decomposition of diborane and methane. The chemical composition, infrared absorption, optical absorption, and microhardness of these thin films were measured. As a function of increasing diborane concentration in the feedstock, we observe increasing boron and hydrogen concentrations, increasing infrared absorption at 1330 cm−1 due to boron icosahedra, increasing optical bandgaps, and an unchanging microhardness in the grown films. The microhardness should have decreased due to the increasing hydrogen concentration; this expected decrease may have been balanced by an increased microhardness due to the boron icosahedra.
Detonation and critical diameter of heterogeneous explosives

Abstract A kinetic lattice model of heterogeneous detonation reaction is developed which treats localized ignition and grain burning as an integral part of the detonation reaction, and which allows the reaction time to be defined in terms of a large set of competing reaction rates, defined for all the components of an explosive mixture. Coupling the lattice reaction rate equations to hydrothermodynamic equations for non-ideal detonation defines an initial value problem which describes the region of stable detonation. Numerical solution of the problem in velocity-density space leads to a determination of the critical diameter of the explosive as well as to a determination of physical and/or chemical parameters (e.g. loading density and particle size) that can yield nonstable detonations. Examples are shown that predict the explosive group behavior described by Price and the critical diameters for several types of explosive materials.
Research on propagation regularity of voltage sags in power system

Voltage sag is a major power quality problem, which could disrupt the operation of voltage sensitive equipment. The fault in transmission and distribution lines of the power system creates voltage sags. It's important to analyze the voltage sags caused by faults in high voltage systems to solve the voltage sag problems of customers. A fully digital power system simulation tool, EMTDC/PSCAD, was applied to build a system model of a large power customer, a large quantity of simulating calculation about voltage sags was carried out. It demonstrates the possible application of the platform and affordable means to study different cases of these problems.
Pioneer Factors in Embryonic Stem Cells and Differentiation

Most studies of tissue-specific and developmental stage-specific transcription have focused on the DNA motifs, transcription factors, or chromatin events required for the active transcription of a gene in cells in which the gene is expressed, or for its active or heritable silencing in nonexpressing cells. However, accumulating evidence suggests that, in multicellular eukaryotes, enhancers or promoters for tissue-specific genes interact with pioneer transcription factors in embryonic stem cells and at other early stages of development, long before the genes are transcribed. These early interactions, which can lead to the presence of unmethylated CpG dinucleotides, histone modification signatures, and/or chromatin remodeling, may carry out different functions at different classes of genes.
Confidence intervals for Assessing Heterogeneity in Generalized Linear Mixed Models

Generalized linear mixed models are frequently applied to data with clustered categorical outcomes. The effect of clustering on the response is often difficult to practically assess partly because ...
Reconstructing geographical-spectral pattern in cognitive radio networks

The geographical-spectral pattern of interruptions from primary users within an area is important for upper layer issues like routing and congestion control in cognitive radio networks. The pattern can be considered as an image and can be recovered from reports of secondary users, like random samples for reconstructing an image. Gibbs random fields are used to model the image by employing an energy function to incorporate correlations between neighboring pixels and a priori hyperparameters. Bayesian compressed sensing is then used to reconstruct the image based on the assumption that the image is sparse in a certain transform domain. The performance of the image reconstruction is demonstrated by numerical simulations.
Three Heads are Better than One

Machine translation (MT) systems do not currently achieve optimal quality translation on free text, whatever translation method they employ. Our hypothesis is that the quality of MT will improve if an MT environment uses output from a variety of MT systems working on the same text. In the latest version of the Pangloss MT project, we collect the results of three translation engines---typically, subsentential chunks---in a chart data structure. Since the individual MT systems operate completely independently, their results may be incomplete, conflicting, or redundant. We use simple scoring heuristics to estimate the quality of each chunk, and find the highest-score sequence of chunks (the "best cover"). This paper describes in detail the combining method, presenting the algorithm and illustrations of its progress on one of many actual translations it has produced. It uses dynamic programming to efficiently compare weighted averages of sets of adjacent scored component translations. The current system operates primarily in a human-aided MT mode. The translation delivery system and its associated post-editing aide are briefly described, as is an initial evaluation of the usefulness of this method. Individual MT engines will be reported separately and are not, therefore, described in detail here.
Thermalization and Lyapunov exponents in Yang-Mills-Higgs theory

We investigate thermalization processes occurring at different time scales in the Yang-Mills-Higgs system at high temperatures. We determine the largest Lyapunov exponent associated with the gauge fields and verify its relation to the perturbatively calculated damping rate of a static gauge boson.
A Siting Policy for an Acceptable Nuclear Future

A nuclear siting policy leading to a few, large concentrated sites, it is argued, is preferable in the long run to the present policy which could lead to many dispersed sites. Such a policy could be implemented incrementally if requirements for new nuclear generating capacity were met by adding reactors to the existing 100-odd sites. Such a concentrated nuclear siting policy would, to some extent, isolate nuclear activities while augmenting the strengths of the institutions responsible for managing them. Additionally, it would confer an element of permanence on the sites and thereby open new options fer managing low level wastes and reactor decommissioning. These actions may improve the public acceptability of nuclear energy in the United States as well as lead to a more rational contained nuclear system in the long run.
Uptake of Fe(II) and Mn(II) on chitin as a model organic phase

The sorption of Fe(II) and Mn(II) onto chitin has been measured in seawater as a function of pH (3–9), temperature (5–45°C), and salinity (0–35). The two metals showed markedly different pH effects. Uptake of Fe(II) was greatest at high pH, whereas Mn(II) showed negligible uptake above pH 6.3–7.3 and precipitated at high pH. The decrease in Mn(II) uptake above pH 6.3–7.3 could be related to the second acid dissociation site of chitin, which has p∗Ka2 = 6.4. Fe(II) follows a Langmuir isotherm at pH 8.2 at intermediate concentrations, as did Mn(II) below pH 6.3. Uptake of both metals increased with temperature from 5 to 45°C, yielding a calculated sorption enthalpy of 14.2 ± 0.6 kJ mol−1 g−1 chitin for Fe(II) and 11 ± 3 kJ mol−1 g−1 for Mn(II) at pH 4. Increasing salinity from zero to 35 increased the uptake of Fe(II) by 50%; at pH 4 the Mn(II) uptake also increased substantially. Calculations indicate that uptake onto chitin-like material cannot account for the partitioning between dissolved and particulate forms of either Mn(II) or Fe(II) in two typical anoxic systems (the Black Sea and Framvaren fjord).
Inhibition of the phospholipase A2 activity of peroxiredoxin 6 prevents lung damage with exposure to hyperoxia.

Lung injury associated with hyperoxia reflects in part the secondary effects of pulmonary inflammation and the associated production of reactive oxygen species due to activation of NADPH oxidase, type 2 (NOX2). Activation of NOX2 requires the phospholipase A2 (PLA2) activity of peroxiredoxin 6 (Prdx6). Therefore, we evaluated whether blocking Prdx6 PLA2 activity using the inhibitor MJ33 would be protective in a mouse model of acute lung injury resulting from hyperoxic exposure. Mice were treated with an intraperitoneal injection of MJ33 (2.5 nmol/g body weight) at the start of exposure (zero time) and at 48 h during continuous exposure to 100% O2 for 80 h. Treatment with MJ33 reduced the number of neutrophils and the protein content in the fluid obtained by bronchoalveolar lavage, inhibited the increase in lipid peroxidation products in lung tissue, decreased the number of apoptotic cells in the lung, and decreased the perivascular edema associated with the 80 h exposure to hyperoxia. Thus, blocking Prdx6 PLA2 activity by MJ33 significantly protected lungs against damage from hyperoxia, presumably by preventing the activation of NOX2 and the amplification of lung injury associated with inflammation. These findings demonstrate that MJ33, a potent inhibitor of Prdx6 PLA2 activity, can protect mouse lungs against the manifestations of acute lung injury due to oxidative stress.
Children with autism demonstrate circumscribed attention during passive viewing of complex social and nonsocial picture arrays

Although circumscribed interests are a hallmark characteristic of autism spectrum disorders, providing a means for quantifying their functional impairment has proven difficult. We developed a passive viewing task to measure aspects of visual attention in children with autism spectrum disorders and typically developing controls. Task stimuli included picture arrays that were matched for social and nonsocial content. Nonsocial content was balanced to include items related to circumscribed interests (e.g., trains) as well as more commonplace items (e.g., furniture). Discrete aspects of gaze behavior were quantified using eye-tracking technology. Results indicate that visual attention in the autism group was more circumscribed (as indicated by the exploration of fewer images), more perseverative (as indicated by longer fixation times per image explored), and more detail oriented (as indicated by a greater number of discrete fixations on explored images). This pattern of results was similar for both social and object arrays. Within the autism group, overall severity of repetitive behavior symptoms correlated positively with exploration of object pictures and negatively with perseveration on social pictures. Results suggest that children with autism have a domain-general pattern of atypical visual attention that may represent an exaggeration of a typical attentional process and is related to a tendency to perseverate on images of interest and explore them in a more detail-oriented manner. Discrete measures of visual attention may therefore provide a reasonable means of quantifying aspects of the repetitive behavior phenotype in autism.
Phylogeny of immune recognition: fine specificity of fish immune repertoires to cytochrome C.

Abstract Using the structurally defined protein antigen cytochrome C, studies were conducted in an attempt to delineate the fine specificities of channel catfish immune repertoires. We have previously reported that species variants of cytochrome C were cross-stimulatory to peripheral blood leukocytes (PBL) from catfish immunized with the pigeon variant. Molecular database analyses revealed the existence of overlapping epitopes that appear to define the specificity of the immune response to a “family” of closely related antigens. To further explore these observations, studies were conducted to determine the contribution of peptide 81–104 to the immunogenicity of cytochrome C. Current data showed that peptide 81–104 and intact cytochrome C were stimulatory to PBL from fish previously immunized with the native molecule. In contrast, PBL from fish previously primed with the peptide 81–104 responded only to the immunizing peptide as well as to some, but not all, variants of the peptide 81–104. The differences in the stimulatory capacities of the peptide variants appeared to correlate with amino acid substitutions at various positions of the peptide and changes in their predicted secondary structures.
Stable arrangements of mobile sensors for sampling physical fields

Today's wireless sensor nodes can be easily attached to mobile platforms such as robots, cars and cell phones enabling pervasive sensing of physical fields (say of temperature, vibrations, air quality and chemicals). We address the sensor arrangement problem, i.e. when and where sensors should take samples to obtain a good estimate of a field using mobile sensors. In particular, we focus on incidentally mobile sensors that move passively under the influence of the environment (e.g. sensors attached to floating buoys, cars and smartphones carried by humans). We model the field as a linear combination of known basis functions. Given the samples, we use a linear estimator to find unknown coefficients of the basis functions. We formulate the sensor arrangement problem as one of finding suitably characterized classes of sensor arrangements that lead to a stable reconstruction of the field. We consider a family of multidimensional δ-dense sensor arrangements, where any square disc of size δ contains at least one sample, and derive sufficiency conditions for the arrangement to be stable. δ-dense sensor arrangements are geometrically intuitive and are easily compatible with the incidental mobility of sensors in many situations. We present simulation results on the stability of such arrangements for two-dimensional basis functions. We also present an example for constructing basis functions through proper orthogonal decompositions for a one-dimensional chemical diffusion field in a heterogeneous medium, which are later used for field estimation through δ-dense sampling.
Ultrastructural study of mouse olfactory epithelium following destruction by ZnSO4 and its subsequent regeneration

Regeneration of olfactory epithelium was studied at the ultrastructural level in two different strains of mice (C57B1/6J and SWR/J) following destructive changes induced by nasal irrigation with 1% aqueous solution of zinc sulfate (ZnSO4). Three epithelial conditions were seen during the first four to 14 days following treatment: a "surface alteration" state characterized by changes at the apical ends of olfactory and columnar supporting cells, a "squamous-metaplastic" state, and a simple-squamous" state. In the latter two conditions, thought to represent regenerative states, cells contained inclusions similar to secretion granules in Bowman's glands. This observation supports earlier suggestions that new epithelial cells originate from these glands. Later regenerative changes consist of differentiation of new sensory cells and columnar supporting cells in an initially disorganized epithelium. This epithelium then changes to a normal, pseudostratified organization. Regeneration of the epithelium begins earlier and proceeds more rapidly in the SWR/J strain than C57B1/6J mice. Possibly, a genetic difference exists between strains. After 72 days the epithelium in both strains had regenerated.
Approximations and Bounds for the Distribution of the Scan Statistic

Abstract The scan statistic is used in many areas of science to test the null hypothesis of uniformity against a clustering alternative. This article derives approximations and bounds for the distribution of scan statistics. An extensive simulation study is carried out to compare the approximations and the bounds derived in this article with other known approximations and bounds. The new lower and upper bounds that have been derived are very useful in evaluating the approximations and the simulation. A quantity of average number of points in the scanning interval of length d, μd , is introduced to study the approximations for the distribution of the scan statistic. For low values of μd the approximation derived in this article is the most accurate one. The importance of the scan statistics arises from their applications in many areas, including nuclear physics, geology, radio-optics, photography, and epidemiology.
O-methylation of estrogens by thermal degradation of their tetramethylammonium salts.

Abstract The thermal elimination of trimethylamine from the monotetramethylammonium salt of estradiol, estriol, or estrone produces the 3-monomethyl ether in essentially quantitative yield. When a large excess of tetramethylammonium hydroxide is employed, the dimethyl ether of estradiol is obtained from estradiol and the trimethyl ether of estriol is obtained from estriol, both in excellent yield. The methylated products are easily recovered in a high degree of purity as crystalline sublimates when the thermal elimination reaction is carried out in a vacuum sublimation reactor. The procedure is a simple one, consisting of one step, and requiring less than two hours.
Mathematical Modeling of a Molten-Carbonate Fuel Cell Using MathCAD

The topic of fuel cells remains novel in most of the engineering programs. While a good selection of textbooks has been introduced, the need for enlightening and achievable projects and homework problems remains strong. The application of MathCAD to a molten-carbonate fuel cell course project is presented. This work effectively brings together the authors’ efforts to offer students the cutting edge experiences in thermal sciences and fuel cell theory. It has been shown that the topic of fuel cells can naturally be introduced from the coverage of reacting systems and combustion in particular. Likewise, there has been a significant development of a uniform mathematical model of a variety of thermodynamic phenomena employing MathCAD, with a considerable increase in the difficulty level of problems that can be completed by the student. MathCAD functionality has been applied to problems in Thermodynamics, Energy Systems, Internal Combustion Engines, and now Fuel Cells. The principles of modeling the carbon-hydrogen-oxygen-nitrogen (CHON) systems have been extended to reflect the thermo- and electro-chemical processes in fuel cells, which includes the dynamically shifting Nernst potential as reactants flow through the fuel cells. Operational parameters, like fuel and oxidizer utilization, can also be evaluated. The intent of this paper is to demonstrate how MathCAD can be used to perform very powerful calculations for fuel cell applications while the intuitive solving structures and mathematical report-like worksheets created in MathCAD promote learning of fuel cell topics. The presented project model can be broken into progressive assignments or just individual homework problems in an undergraduate applied thermodynamics or fuel cell applications course.Copyright © 2008 by ASME
Clinical and electrophysiologic effects of chronic lorcainide therapy in refractory ventricular tachycardia.

The clinical, electrophysiologic and pharmacologic effects of chronic lorcainide therapy in patients with refractory ventricular tachycardia were evaluated using programmed electrical stimulation. Twelve patients with recurrent refractory ventricular tachycardia and organic heart disease, 10 men and 2 women aged 41 to 76 years, with no evidence of prior high degree atrioventricular or bifascicular block were studied. Programmed electrical stimulation was performed in the control, drug-free state and after chronic administration of lorcainide (dose range 200 to 600 mg/day, duration 48 to 240 hours, mean 106 hours) in 11 patients. One patient developed intolerable drug side effects and treatment was discontinued after 36 hours. In the 11 other patients, there was a significant increase in PR interval (187 ± 55 to 219 ± 56 ms; p 0.2). The ventricular effective refractory period increased from 234 ± 21 to 266 ± 15 ms (p Long-term lorcainide therapy was continued in the four responders. During a 2 to 12 month follow-up period, two patients have remained arrhythmia-free, one patient developed intolerable side effects requiring discontinuation of the drug and one patient with advanced renal failure died. It is concluded that chronic lorcainide therapy has significant electrocardiographic and electrophysiologic effects, but has a limited role in the long-term treatment of patients with refractory sustained ventricular tachycardia.
Dextranase Activity in Coleoptiles of Avena

Ani enzyme activity similar to that of dextranase is associated with coleoptiles of Avena sativa. When subjected to purified dextranase, both the pure natural dextran and the cell walls of the Avena coleoptiles yield isomaltose and isomaltotriose. Thus, the cell walls contain dextrans or dextran-like compounds. Coleoptiles with low auxin content have a lower dextranase activity than coleoptiles with high auxin content. The enzyme activity is therefore in some way sensitive to thle hormone.
Effect of seminal plasma on the cryopreservation of equine spermatozoa

Seminal plasma is generally removed from equine spermatozoa prior to cryopreservation. Two experiments were designed to determine if adding seminal plasma back to spermatozoa, prior to cryopreservation, would benefit the spermatozoa. Experiment 1 determined if different concentrations of seminal plasma affected post-thaw sperm motility, viability and acrosomal integrity of frozen/thawed stallion spermatozoa. Semen was washed through 15% Percoll to remove seminal plasma and spermatozoa resuspended to 350 x 10(6)sperm/mL in a clear Hepes buffered diluent containing either 0, 5, 10, 20, 40 or 80% seminal plasma for 15 min, prior to being diluted to a final concentration of 50 x 10(6)sperm/mL in a Lactose-EDTA freezing diluent and cryopreserved. Sperm motility was analyzed at 10 and 90 min after thawing, while sperm viability and acrosomal integrity were analyzed 20 min after thawing. Seminal plasma did not affect sperm motility, viability or acrosomal integrity (P>0.05). Experiment 2 tested the main affects of seminal plasma level (5 or 20%), incubation temperature (5 or 20 degrees C) and incubation time (2, 4 or 6 h) prior to cryopreservation. In this experiment, spermatozoa were incubated with 5 or 20% seminal plasma for up to 6h at either 5 or 20 degrees C prior to cryopreservation in a skim milk, egg yolk freezing extender. Samples cooled immediately to 5 degrees C, prior to freezing had higher percentages of progressively motile spermatozoa than treatments incubated at 20 degrees C (31 versus 25%, respectively; P<0.05), when analyzed 10 min after thawing. At 90 min post-thaw, total motility was higher for samples incubated at 5 degrees C (42%) compared to 20 degrees C (35%; P<0.05). In addition, samples containing 5% seminal plasma had higher percentages of total and progressively motile spermatozoa (45 and 15%) than samples exposed to 20% seminal plasma (33 and 9%; P<0.05). In conclusion, although the short-term exposure of sperm to seminal plasma had no significant effect on the motility of cryopreserved equine spermatozoa, prolonged exposure to seminal plasma, prior to cryopreservation, was deleterious.
Studies of space and time resolved emission measurements of an ArF excimer laser ablated plasma

Abstract A laser ablated plasma created by an ArF excimer laser of wavelength of 193 nm, laser power of 150-200 mJ, repetition rate of 1 Hz, and zinc, copper, iron and nickel targets was studied. Quantitative emission studies are reported that are both space and time resolved. The space results of the laser ablated plasma suggest a confined plasma with a gaussian type distribution of atoms and ions. The time resolved studies show a maximum emission signal occurring at approximately 20 μs with a lifetime of less than 100 μs.
Preeclampsia: an imbalance in placental prostacyclin and thromboxane production.

Preeclampsia is characterized by increased vasoconstriction frequently associated with increased platelet aggregation, reduced uteroplacental blood flow, and premature delivery. Because prostacyclin antagonizes the vasoconstrictor, platelet-aggregating, and uterine-activating actions of thromboxane, we considered the hypothesis that placental production of thromboxane was increased coincident with decreased production of prostacyclin in preeclampsia. Fresh human term placentas were obtained immediately after delivery from 11 normal and 10 preeclamptic pregnancies (blood pressure 140190 mm Hg, urinary protein >0.3 gm/24 hr). Tissues (350 mg) were incubated sterilely in 6 ml of Dulbecco's Modified Eagle's Medium for 48 hours at 37° C with 95% oxygen and 5% carbon dioxide in a metabolic shaker. Samples were collected at 8, 20, 32, and 48 hours and analyzed for thromboxane by radiommunoassay of its stable metabolite, thromboxane B2, and for prostacyclin by radioimmunoassay of its stable metabolite, 6-keto prostaglandin F 1α . The production of thromboxane was significantly increased in preeclamptic versus normal placental tissue (22.9 ± 4.7 versus 6.3 ± 1.5 pglmglhr, mean ± SE, p 0.50) by arachidonic acid (100 µmol/L). Therefore, during normal pregnancy, the placenta produces equivalent amounts of thromboxane and prostacyclin, so that their biologic actions on vascular tone, platelet aggregation, and uterine activity will be balanced. In preeclamptic pregnancy, however, the placenta produces seven times more thromboxane than prostacyclin.
Renewable Energy Systems Instability Involving Grid-Parallel Inverters

This paper presents a study of renewable energy system stability based on impedance models of the sources and the grid. The focus is grid-parallel inverters controlled in the current injection mode. System stability analysis based on source output impedance and load input impedance is generalized to current-source systems. Output impedance modeling of current-controlled PWM inverters for grid interface of renewable sources is presented to provide the necessary impedance models for system stability analysis. The effects of current control loop design and output filter configurations on the inverter output impedance are considered. A practical method to measure grid impedance using a frequency analyzer is presented, and the associated difficulties due to the presence of harmonics in the grid voltage are discussed. An example system involving a single-phase grid-connected inverter is presented to demonstrate the application of the proposed system analysis method.
Cutaneous photobiology: past, present and future.

The history and origin of the science of photobiology are reviewed. Interest in the biologic effects of light gradually increased, beginning with the discovery of ultraviolet and infrared radiation early in the 19th century. The basis of experimental photobiology was laid by the studies of Raab and Tappeiner on photodynamic action and the early uses of phototherapy by Finsen and Dorno. The discovery of the association of porphyrins with some light-related skin diseases and of the capability of chemical agents such as coal tar and bergamot to induce phototoxic contact dermatitis resulted in a flurry of clinical investigations leading to better understanding of the processes of phototoxicity and photoallergy. The early epidemiologic studies of Unna and Dubreuilh relating solar radiation exposure to the formation of actinic keratoses and non-melanoma skin cancer were experimentally confirmed in animals by Findlay, Roffo, and Blum. In the most recent quarter century (1950–1975), cellular and molecular photobiology has been refined. The studies on photochemistry of nucleic acid and of damage and repair mechanisms in DNA have set the stage for understanding the basic processes of biologic effects of light and promise the development of useful applications of specifically directed phototherapy and prevention of such light-induced diseases as skin cancer.
Genetic suppression analysis of σE interaction with three promoters in sporulating Bacillus subtilis

Genetic evidence suggests that the sigma (sigma) subunit of RNA polymerase determines the specificity of promoter utilization, by making sequence-specific contacts with DNA. We examined the effects of two single amino acid(aa) substitutions in sigma E on the utilization of mutated derivatives of three different promoters in sporulating Bacillus subtilis. We found allele-specific suppression of mutations in all three promoters by each aa substitution in sigma E. These results provide strong evidence that sigma E interacts with each of these promoters in vivo. Moreover, the specificity of suppression of the mutations by the aa substitutions in sigma E lead us to speculate that the Met124 of sigma E closely contacts two adjacent bp in the -10 region of the promoters.
Familial subvalvular aortic stenosis in golden retrievers: inheritance and echocardiographic findings.

Objectives: To describe the echocardiographic findings and pedigree analysis of golden retrievers with subvalvular aortic stenosis. Methods: Seventy-three golden retrievers were evaluated by auscultation and echocardiography. A subcostal continuous-wave Doppler aortic velocity e2·5 m/s and presence of a left basilar systolic ejection murmur were required for diagnosis of subvalvular aortic stenosis. Three echocardiographic characteristics were recorded: evidence of aortic insufficiency, subvalvular ridge or left ventricular hypertrophy. A disease status score was calculated by totalling the number of echocardiographic -characteristics per subject. Results: Thirty-two of 73 dogs were affected and their aortic velocities were as follows: range 2·5 to 6·8 m/s, median 3·4 m/s and standard deviation 1·2 m/s. Echocardiographic characteristics of 32 affected dogs were distributed as follows: left ventricular hypertrophy 12 of 32, aortic insufficiency 20 of 32 and subvalvular ridge 20 of 32. Disease status score ranged from 0 to 3 with a median of 2. There was a statistically significant correlation between aortic velocity and disease status score (r=0·644, P<0·0001). Subvalvular aortic stenosis was observed in multiple generations of several families and appears familial. Clinical Significance: Subvalvular aortic stenosis in the golden retriever is familial. Severity of stenosis correlates well with cumulative presence of echocardiographic characteristics (left ventricular hypertrophy, subvalvular ridge and aortic insufficiency).
COX-2 in cancer: Gordian knot or Achilles heel?

The networks of blood and lymphatic vessels and of the extracellular matrix and their cellular and structural components, that are collectively termed the tumor microenvironment, are frequently co-opted and shaped by cancer cells to survive, invade and form distant metastasis. With an enviable capacity to adapt to continually changing environments, cancer represents the epitome of functional chaos, a stark contrast to the hierarchical and organized differentiation processes that dictate the development and life of biological organisms. The consequences of changing landscapes such as hypoxia and acidic extracellular pH in and around tumors create a cascade of, or themselves are results of, changes in multiple pathways and networks that become apparent only several years later as recurrence and metastasis. These molecular and phenotypic changes approach the complexities of a ‘Gordian Knot’. We review evidence from our studies and from literature suggesting that COX-2 biology presents a nodal point in cancer biology and an ‘Achilles heel’ of COX-2-dependent tumors.
63Cu nuclear magnetic relaxation in Cu-Ni alloys near the critical concentration

Abstract The nuclear spin lattice relaxation time of 63 Cu in CuNi alloys is found to be independent of composition near the magnetic transition.
A NOTE ON COCCIDIA IN SPARROWS AND THEIR ASSUMED RELATION TO BLACKHEAD IN TURKEYS

Of 54 sparrows examined in or near Princeton, coccidia were found in 43, or 80 per cent. Most of the negative cases were encountered in November and December. In the summer and fall practically all were infected. These figures agree closely with Hadley's, who found 79 per cent infected from May to December. Cultures of feces on agar showed that, at least in this locality, the infecting species belongs to the genus Isospora or Diflospora and not to Eirneria. In a recent paper by Hadley, which came into our hands after the manuscript had gone to press, the author now refers blackhead to invasions of Trichomonas. It is not possible to consider here the evidence on which this conclusion is based.
Pigeon breeders' disease: Immunofluorescent localization of sensitizing antigens in pigeon

Abstract Sera from two pigeon breeders, one with active pigeon breeders' disease (PBD), reacted specifically in indirect immunofluorescence (IF) with cryostat sections of pigeon gastrointestinal tract and trachea mucosa and testis. The IF test appears to be highly sensitive and reliable for localizing and identifying the offending pigeon antigens and for detecting antibodies.
Impaired Hearing in Mice Lacking Aquaporin-4 Water Channels

A role for aquaporins (AQPs) in hearing has been suggested from the specific expression of aquaporins in inner ear and the need for precise volume regulation in epithelial cells involved in acoustic signal transduction. Using mice deficient in selected aquaporins as controls, we localized AQP1 in fibrocytes in the spiral ligament and AQP4 in supporting epithelial cells (Hensen's, Claudius, and inner sulcus cells) in the organ of Corti. To determine whether aquaporins play a role in hearing, auditory brain stem response (ABR) thresholds were compared in wild-type mice and transgenic null mice lacking (individually) AQP1, AQP3, AQP4, and AQP5. In 4–5-week-old mice in a CD1 genetic background, ABR thresholds in response to a click stimulus were remarkably increased by >12 db in AQP4 null mice compared with wild-type mice (p
Brainstem reticular formation mechanisms subserving generalized seizures: Effects of convulsants and anticonvulsants on sensory-evoked responses

Abstract 1. 1. Sensory-evoked potentials of the brain are enhanced in many models of generalized seizure including those produced by administration of a wide variety of convulsant agents. 2. 2. The amplitude of sensory-evoked potentials is reduced by administration of several anticonvulsant drugs. 3. 3. Sensory-evoked potentials from non-primary sensory brain sites are more greatly enhanced by convulsants than those in primary sensory sites. 4. 4. Enhancement of reticular formation sensory-evoked potentials occurs with smaller amounts of convulsant than those which enhance responses in other non-primary sites. 5. 5. The responses of reticular formation neurons to sensory stimuli are greatly enhanced by administration of several convulsant agents. 6. 6. The enhancement of neuronal responses to sensory stimuli appears to be one of the mechanisms subserving convulsant-induced enhancement of sensory-evoked potentials. 7. 7. Although many convulsants have been considered to act primarily by affecting specific neurotransmitters, recent evidence suggests that convulsants may possess a common neuronal effect. 8. 8. This common effect of convulsant agents may reveal a general pathophysiological brain mechanism subserving generalized seizure development. 9. 9. These seizure mechanisms may involve reversal of the synaptic events involved in habituation or intensification of the processes involved in the startle response.
Activity of Trypsin in Solution Through Membranes.

Summary and ConclusionsFormvar, parlodion and collodion membranes have been prepared by impregnating paper with solutions of these substances. A suitable cell of two compartments was constructed in which solutions of trypsin and hemoglobin could be separated by the membranes.Interaction between solutions of trypsin and hemoglobin separated by formvar, parlodion or collodion membranes has been demonstrated.Examination of a series of membranes impregnated with collodion of different concentrations showed that interaction decreased in a curvilinear fashion as the collodion concentration in the membranes was increased.
Abstract B194: Enhanced antitumor activity of the HIF‐1 inhibitor PX‐478 combined with radiation and chemotherapy in pancreatic cancer

Growing tumors respond to hypoxic stress through increased expression of the HIF‐1α transcription factor resulting in an adaptive switch to glycolytic metabolism, angiogenic signaling, survival, and metastasis. HIF‐1α expression is associated with tumor resistance to cytotoxic therapy and inferior clinical outcomes. Pancreatic cancer is frequently associated with extensive desmoplasia, hypovascularity, and hypoxia, and is resistant to chemotherapy and radiation treatment. We have observed that HIF‐1α is increased compared to normal pancreatic tissue in 24/32 (75%) of patent pancreatic ductal carcinoma samples, while 43% of the surrounding stromal tissue also showed elevated HIF‐1α. Distal stroma showed no increase in HIF‐1α. We have investigated the effects of the novel selective HIF‐1α inhibitor PX‐478 currently in Phase I clinical trial, on the in vitro and in vivo radiation response of human pancreatic cancer models. In pancreatic cancer cell lines, inhibition of HIF‐1α by PX‐478 was associated with increased cell killing by radiation with a radiation enhancement factor at 0.2 surviving fraction (SF2) in hypoxia (1% O 2 ) of between 1.3 and 1.4. In mice with Panc‐1 xenografts, 1 Gy QD alone × 5 yielded a tumor inhibition T/C at 70 days of 65% (with no regression), PX‐478 20mg/kg po QD × 5 yielded a T/C of 14% (with 41% tumor regression) and the combination of 20mg/kg po PX‐478 given daily 4 hr before 1 Gy × 5 provided a T/C of 8% (with 81% tumor regression). In CF‐PAC‐1, or SU.86.86 sc pancreatic xenografts, concurrent administration of 10 mg/kg PX‐478 potentiated the antitumor effects of fractionated radiation and 5FU 20 mg/kg iv QD × 5 with a T/C of up to 3%, and with 66% tumor regression. In Panc‐1 and SU.86.86 xenografts 20 mg/kg PX‐478 potentiated the antitumor effects of radiation in combination with gemcitabine 120 mg/kg ip Q3D given one week later with a T/C of up to 8%, and with 80% tumor regression. Early tumor responses to combined PX‐478/radiation treatment could be rapidly quantified by clinically relevant vascular imaging biomarkers. DCE‐MRI and ultrasound imaging reproducibly discriminated tumor responses to PX‐478 alone or combined with radiation as early as 10 days post‐treatment, before differences in anatomic tumor size could be detected. Therefore, PX‐478 is a mechanistically appealing and potentially clinically relevant enhancer of pancreatic cancer radiosensitivity, inhibiting tumor and stromal HIF‐1 pro‐angiogenic signaling and reducing the innate radiation resistance of hypoxic tumor cells. Supported by CA CA109552‐05. Citation Information: Mol Cancer Ther 2009;8(12 Suppl):B194.
A national study of HPV vaccination of adolescent girls: rates, predictors, and reasons for non-vaccination.

Despite recommendations in the U.S. for routine HPV vaccination of adolescent girls since 2006, rates of vaccination continue to be low. This study reports vaccination uptake, factors associated with vaccine uptake and reasons for non-vaccination within a national sample of adolescent females during 2010. Using a computer administered survey of a national sample of 501 mothers of daughters 14–17 years old we assessed maternal reports of HPV vaccination as well as socio-demographical factors, maternal HPV exposures and reasons chosen for non-vaccination. Reported HPV vaccination rates were slightly over 50 % (51.1 %), with 38.3 % reporting completion of all 3 doses. Socioeconomic and demographic factors were not associated with vaccination initiation; however, Blacks and Hispanics were less likely to complete vaccination. The most common reasons for non-vaccination were concerns about vaccine safety, danger to daughter, and provider non-recommendation. Relatively poor HPV vaccine initiation and only modest 3-dose completion continues to be a major public health concern that requires continued efforts to address identified predictors and reasons for non-vaccination.
Outcomes of morbidly obese patients requiring mechanical ventilation for acute respiratory failure.

Objective: To examine the outcomes of morbidly obese patients with acute respiratory failure treated with mechanical ventilation. Design: Retrospective study. Setting: A 14-bed medical intensive care unit in an 800-bed university-based hospital. Patients: A total of 50 morbidly obese subjects with acute respiratory failure requiring ventilatory assistance. Interventions: None. Measurements: Arterial blood gas measurements, intubation rate, days of mechanical ventilation, intensive care unit length of stay, hospital length of stay, and mortality. Results: From January 1997 to December 2004, 50 morbidly obese patients with acute respiratory failure were treated with mechanical ventilation. Invasive mechanical ventilation was implemented in 17 patients with a mean body mass index of 53.2 ± 12.2 kg/m 2 . A total of 33 patients were treated with noninvasive ventilation (NIV), of which 21 avoided intubation (NIV success) and 12 required intubation (NIV failure). Mean body mass index for the NIV success group was significantly less than for the NIV failure group (46.9 ± 8.9 and 62.5 ± 16.1 kg/m 2 , respectively, p = .001). Acute Physiology and Chronic Health Evaluation II scores were similar for patients treated with invasive and noninvasive ventilation. Significant improvements in pH and PaC0 2 were noted for the invasive mechanical ventilation and NIV success groups. No improvements in gas exchange were noted in the NIV failure group. Of patients treated with NIV, 36% required intubation. Hospital mortality for the invasive ventilation and NIV failure groups was increased. Conclusion: The type of ventilatory assistance may influence clinical outcomes in morbidly obese patients with acute respiratory failure.
Certain Multiplets in the Spectra of Cb III and Cb IV

Relative positions of certain multiplets in two and three electron systems of the second long period with wave-lengths for Zr III, Cb IV and Cb III.---Applying the irregular doublet law to the data already known for the triad of multiplets $^{3}DF$, $^{3}D{D}^{\ensuremath{'}}$, and $^{3}DP$, ($ds\ensuremath{-}dp$) in the two electron systems of Sr I and Yt II, the corresponding multiplets for Zr III and Cb IV have been identified. Similarly the triad of multiplets $^{4}F^{\ensuremath{'}}{D}^{\ensuremath{'}}$, $^{4}F^{\ensuremath{'}}F$, and $^{4}F^{\ensuremath{'}}{G}^{\ensuremath{'}}({d}^{2}s\ensuremath{-}{d}^{2}p)$ in the three electron systems of Yt I and Zr II has been extended to Cb III and the stronger lines of the $^{4}F^{\ensuremath{'}}{G}^{\ensuremath{'}}$ multiplet of Mo IV. In passing successively from element to element in both of these isoelectronic systems the shift in the frequency of the radiated lines for each of these multiplets is approximately constant.
Union views of managerial prerogatives revisited: The prospects for labor-management cooperation

Using data from a survey of AFL-CIO affiliated unions, I compare union views of managerial prerogatives in 1997 with those reported in a 1968 study. Unions today desire more input into the firm's decision-making process than in 1968, particularly with regard to issues traditionally reserved to management. Given management's traditional resistance to “outside” interference, more cooperative relationships between unions and managment may be problematic.