cssi/SciSciGPT-SciSciNet huggingface dataset:
PHYSICAL AND METABOLIC FACTORS IN GALLSTONE PATHOGENESIS

Gallstones form as the culmination of a complex series of events that results in precipitation of insoluble substances in the gallbladder. Bile contains bile salts, physiologic detergents that can solubilize lipids. Bile salts allow the liver to excrete relatively insoluble molecules in bile and aid in the absorption of dietary lipids in the intestine. Gallstones occur when insoluble lipids and inorganic salts secreted by the liver cannot be solubilized as they normally are in bile by the detergent properties of bile salts. For this to occur, metabolic events must take place to produce bile that contains excess amounts of either cholesterol or bilirubin, both of which are relatively insoluble in aqueous solution. Additionally, physical factors must allow rapid nucleation within the residence time of bile in the biliary tree. Gallstones are divided into three major types: (1) cholesterol, (2) black pigment, and (3) brown pigment, depending on their composition and hence on their pathogenesis. Cholesterol gallstones, which constitute greater than 80% of stones in the Western world, are composed predominantly of crystals of the sterol cholesterol. 122 Stones can be almost pure cholesterol and contain cholesterol monohydrate crystals agglomerated by a mucin glycoprotein matrix. Minor components of cholesterol stones include unconjugated bilirubin and small amounts of calcium phosphate. Black pigment gallstones contain calcium salts of unconjugated bilirubin, in a polymerized matrix. 85 The additional presence of calcium phosphate in the mucin matrix results in opacity of black pigment stones on plain radiographs. The hallmark of brown pigment gallstones is the presence of bacterial degradation products of biliary lipids, calcium salts of fatty acids and unconjugated bilirubin, 30 in addition to precipitated cholesterol. Cholesterol and black pigment stone formation is characterized by abnormalities in cholesterol and bilirubin metabolism. In contrast, brown pigment stone formation occurs only as a result of bacterial infection of the biliary tree, typically in the presence of bile stasis. This article discusses metabolic factors that underlie secretion of supersaturated bile and physical factors that allow solubilization and precipitation of the biliary lipids and calcium salts that constitute gallstones.
Effect of angiotensin II on microvascular permeability.

Abstract Background. Angiotensin II (Ang II) is a potent vasoconstrictor that is released during shock and sepsis. It is known to have activity on vascular endothelial cells. We hypothesized that Ang II plays a role in the modulation of fluid flux across the microvascular endothelium. Materials and methods. Hydraulic permeability ( L p ) is a measure of water flow across the endothelial barrier. L p was measured in rat mesenteric venules using the modified Landis micro-occlusion technique. To determine the effect of Ang II in basal states, venules were perfused with control Ringer's and measures of L p obtained before and after a subsequent perfusion with 20 ng/ml Ang II ( n = 5). In additional studies 10 μM ATP was used to activate the endothelium, thereby increasing the L p approximately 3-fold. Measures of L p were then obtained before and after a subsequent perfusion with 20 ng/ml Ang II ( n = 6). Results. In the basal state, Ang II significantly increased L p from 1.45 ± 0.29 to 3.45 ± 0.28 ( P = 0.013). Following activation by ATP, Ang II decreased L p from 4.51 ± 0.45 to 3.05 ± 0.28 ( P = 0.02). Units for L p are ×10 −7 cm s −1 · cm H 2 O −1 . Conclusions. Ang II increased microvascular permeability under basal conditions while in the activated state it decreased microvascular permeability. In addition to its vasopressor function this differential action of Ang II in modulating fluid flux across the fsendothelium in basal versus activated states may be of benefit under pathophysiological conditions and may be amenable to pharmacologic manipulation.
Ambivalence: The Tension Between “Yes” and “No”

Ambivalence is the painful experience of feeling stuck between polarized feelings about an idea, a thing, or a person. The root of resistance, client ambivalence, is the bane of beginning counselors. To enhance personalized understanding of intrapsychic and interpersonal ambivalence, master's degree students in counseling wrote poems describing their experience of the tension between “yes” and “no.” Examples of their poetry are used to illustrate the many manifestations of ambivalence in human lives.
Cognitive development and adolescent disabilities

In this presentation I will try to bring together the cognitive development and dynamic orientations as they apply to the exacerbation of chronic disabilities and the etiology of new disabilities in adolescents. I am afraid that I will have to use clinical observation and consensual validation as my primary data base as much of what I have to say has yet to be systematically investigated. I hope, therefore, that the presentation may stimulate research as well as discussion. From ancient times, it has been recognized that when children reach the age of six or seven years, they also attain the "age of reason," i.e., the syllogistic reasoning elaborated by Aristotle. It was not until Piaget's groundbreaking work on adolescent thinking (1) that a new higher order of reasoning was given a developmental time tag. Piaget made clear that the propositional logic made prominent by Boole (2) and others was not attained until adolescence. Propositional logic is as different from syllogistic logic as algebra is from arithmetic. Algebra raises arithmetic to a higher power that is at once broader and more abstract. The equation (proposition) (a + b) 2 = a 2 + 2ab + b 2 holds true for whatever numbers are substituted for the letters. Propositional logic thus enables young people to consider possibilities as well as the here-and-now realities. Propositional logic underlies the understanding of historical time and celestial space. It permits young people to understand metaphor and simile (second-order symbols) as well as puns, political cartoons, satire, and allegory. In a very real sense, propositional logic permits teenagers to think in a "new key."
Effects of reduced-rate methyl bromide applications under conventional and virtually impermeable plastic film in perennial crop field nurseries.

BACKGROUND: Producers of perennial crop nursery stock in California use preplant soil fumigation to meet state phytosanitary requirements. Although methyl bromide (MB) has been phased out in many agricultural industries, it is still the preferred treatment in the perennial nursery industry and is used under Critical Use Exemptions and Quarantine/Preshipment provisions of the Montreal Protocol. The present research was conducted to evaluate reduced-rate MB applications sealed with conventional and low-permeability plastic films compared with the primary alternative material. RESULTS: Reduced rates (100–260 kg ha−1) of MB applied in combination with chloropicrin (Pic) and sealed with a low-permeability plastic film provided weed and nematode control similar to the industry standard rate of 392 kg ha−1 MB:Pic (98:2) sealed with high-density polyethylene (HDPE) film. However, the primary alternative chemical, 1,3-dichloropropene (1,3-D), tended to provide slightly lower pest control even on sites with relatively low plant parasitic nematode, soil-borne pathogen and weed pest pressure. CONCLUSION: If California regulations change to allow the use of low-permeability films in broadcast fumigant applications, the results of this research suggest that reduced rates of MB in perennial crop nurseries could serve as a bridge strategy until more technically, economically and environmentally acceptable alternatives are developed. Published 2010 by John Wiley & Sons, Ltd.
Host selection, location, and association behaviors of anemonefishes in field settlement experiments

Nine anemonefish species were reared in the laboratory, and individuals were released in the field (Lizard Island, Australia and Madang, Papua New Guinea) at different distances and orientations away from natural (anemone species the fishes are found with in nature) and unnatural species of host anemones. Experiments were conducted to examine factors that could affect the settlement behaviors of the fishes: current velocity, distance and orientation of the fishes to the anemones, chemical vs visual cues, and presence of conspecific or heterospecific fishes. The fishes were usually attracted toward natural host species of anemones but not towards unnatural host anemone species nor to pieces of dead coral. Host selection during settlement provided the best explanation for the host specificity patterns displayed by anemonefishes in nature. The fishes used chemical cues released from the anemones to identify and locate the appropriate host species and could effectively locate the anemones from a maximum distance of 8 m downstream. Fishes released upstream or to the side of anemones (where anemone chemicals were assumed to be reduced or absent) were much less successful in locating anemones. The ability of the fishes to locate natural host anemones was strongly reduced when there was no water current. The presence of resident anemonefishes on host species of anemones did not influence the attraction behavior of anemonefishes released downstream from the anemones. Once the released fishes got close to or entered the anemones, the resident fishes would generally bite and chase them until the recruits left the anemones. Most fishes were not stung upon initial contact with the anemones.
Bridging Past and Future Climate across Paleoclimatic Reconstructions, Observations, and Models: A Hydroclimate Case Study*

AbstractPotential biases in tree-ring reconstructed Palmer drought severity index (PDSI) are evaluated using Thornthwaite (TH), Penman–Monteith (PM), and self-calibrating Penman–Monteith (SC) PDSI in three diverse regions of the United States and tree-ring chronologies from the North American drought atlas (NADA). Minimal differences are found between the three PDSI reconstructions and all compare favorably to independently reconstructed Thornthwaite-based PDSI from the NADA. Reconstructions are bridged with model-derived PDSI_TH and PDSI_PM, which both closely track modeled soil moisture (near surface and full column) during the twentieth century. Differences between modeled moisture-balance metrics only emerge in twenty-first-century projections. These differences confirm the tendency of PDSI_TH to overestimate drying when temperatures exceed the range of the normalization interval; the more physical accounting of PDSI_PM compares well with modeled soil moisture in the projection interval. Remaining reg...
RELATIONSHIPS BETWEEN GEOPOTENTIAL HEIGHTS AND TEMPERATURE IN THE SOUTH‐EASTERN US DURING WINTERTIME WARMING AND COOLING PERIODS

This paper discusses the relationship between geopotential heights and mean winter surface temperature and the characteristics of interannual variability in the south-eastem USA during cooling and warming periods from 1946 to 1992. Data from 83 Historical Climatology Network stations in 12 south-eastem states were examined. Factor analysis was used to separate the southeast into three climatic regions. These regions were then matched with both 500 hPa and 700 hPa pressure heights during two periods: the 1946-1976 cooling period and the 1976-1992 warming period. The degree of association between geopotential heights and surface temperature was greater during the cooling period than during the warming period. Possible influences may lie with differential temperature modification effects of the Gulf of Mexico and Atlantic Ocean, as well as soil moisture variability. The amount of geopotential height variability, as measured by standard deviations, was also compared between the cooling and warming periods, and was significantly greater during the cooling period. This explains a similar pattern in the surface temperature variability. A possible cause is the susceptibility of troughs to prolongation and amplification during cold winters. Both results suggest that not only is it difficult to determine the forcing mechanisms that cause short-term variability, but that the influence of the forcing mechanisms may not be consistent between cooling and warming periods as well.
Heuristic dynamic programming for neural network vector control of a grid-connected converter

This paper analyzes optimal control of a grid-connected converter (GCC) based on the adaptive critic designs (ACDs), especially on heuristic dynamic programming (HDP). Instead of using a trained model neural network to identify the dynamics of the plant, the paper uses exact GCC plant mathematical model to reflect the system dynamics accurately. Thus, the HDP for GCC only contains a critic neural network and an action neural network, which simplifies the control design. The training cycles of the critic and action networks in our HDP design are combined into one training cycle, which reduces the calculation time and makes it more suitable to online training. Results show that the RNN controller based on the designed HDP exhibits good tracking ability. The weights of the critic and action networks are adjusted online to adapt the changing GCC system automatically.
Electron scattering coincidence studies of nuclear structure

Abstract The high duty cycle beams available from the latest generation of electron accelerators permit the application of electron scattering coincidence techniques to a broad variety of problems in nuclear structure. Potential advantages for studies involving bound states and the giant multipole resonances are discussed.
The PASS theory of intelligence and the acquisition of a complex skill: a criterion-related validation study of Cognitive Assessment System scores

This study extends the empirical research on the planning, attention, simultaneous, and successive (PASS) theory of intelligence and its assessment via the Cognitive Assessment System (CAS) by examining the criterion-related validity of CAS scores with respect to the acquisition of a complex skill. Accordingly, 92 young adult males completed 7 h of training on a computer-based task that simulated the demands of a dynamic aviation environment. Cognitive and skill-based learning were assessed. Although the CAS Full score was correlated with learning, there were differences in the predictive value of the CAS scales. Successive processing was the only CAS scale to explain a unique proportion of variance in all the learning measures. Scores on simultaneous processing made important contributions to cognitive learning, and attention scores were an important contributor to skill-based learning. Planning scores were not significantly related to any of the learning criteria.
Prospects for genomewide selection for quantitative traits in maize

The availability of cheap and abundant molecular markers in maize (Zea mays L.) has allowed breeders to ask how molecular markers may best be used to achieve breeding progress, without conditioning the question on how breeding has traditionally been done. Genomewide selection refers to marker-based selection without fi rst identifying a subset of markers with signifi - cant effects. Our objectives were to assess the response due to genomewide selection compared with marker-assisted recurrent selection (MARS) and to determine the extent to which phenotyping can be minimized and genotyping maximized in genomewide selection. We simulated genomewide selection by evaluating doubled haploids for testcross performance in Cycle 0, followed by two cycles of selection based on markers. Individuals were genotyped for NM markers, and breeding values associated with each of the NM markers were predicted and were all used in genomewide selection. We found that across different numbers of quantitative trait loci (20, 40, and 100) and levels of heritability, the response to genomewide selection was 18 to 43% larger than the response to MARS. Responses to selection were maintained when the number of doubled haploids phenotyped and genotyped in Cycle 0 was reduced and the number of plants genotyped in Cycles 1 and 2 was increased. Such schemes that minimize phenotyping and maximize genotyping would be feasible only if the cost per marker data point is reduced to about 2 cents. The convenient but incorrect assumption of equal marker variances led to only a minimal loss in the response to genomewide selection. We conclude that genomewide selection, as a brute-force and black-box procedure that exploits cheap and abundant molecular markers, is superior to MARS in maize.
Cell Proliferation in Normal Epidermis

A detailed examination of cell proliferation kinetics in normal human epidermis is presented. Using tritiated thymidine with autoradiographic techniques, proliferative and differentiated cell kinetics are defined and interrelated. The proliferative compartment of normal epidermis has a cell cycle duration (Tc) of 311 h derived from 3 components: the germinative labeling index (LI), the duration of DNA synthesis (ts), and the growth fraction (GF). The germinative LI is 2.7% +/- 1.2 and ts is 14 h, the latter obtained from a composite fraction of labeled mitoses curve obtained from 11 normal subjects. The GF obtained from the literature and from human skin xenografts to nude mice is estimated to be 60%. Normal-appearing epidermis from patients with psoriasis appears to have a higher proliferation rate. The mean LI is 4.2% +/- 0.9, approximately 50% greater than in normal epidermis. Absolute cell kinetic values for this tissue, however, cannot yet be calculated for lack of other information on ts and GF. A kinetic model for epidermal cell renewal in normal epidermis is described that interrelates the rate of birth/entry, transit, and/or loss of keratinocytes in the 3 epidermal compartments: proliferative, viable differentiated (stratum malpighii ), and stratum corneum. Expected kinetic homeostasis in the epidermis is confirmed by the very similar "turnover" rates in each of the compartments that are, respectively, 1246, 1417, and 1490 cells/day/mm2 surface area. The mean epidermal turnover time of the entire tissue is 39 days. The Tc of 311 h in normal cells in 8-fold longer than the psoriatic Tc of 36 h and is necessary for understanding the hyperproliferative pathophysiologic process in psoriasis.
Modeling the Sun-to-Earth propagation of a very fast CME

Abstract We present a three-dimensional (3-D) numerical ideal magnetohydrodynamics (MHD) model describing the time-dependent propagation of a CME from the solar corona to Earth in just 18 h. The simulations are performed using the BATS-R-US (Block Adaptive Tree Solarwind Roe Upwind Scheme) code. We begin by developing a global steady-state model of the corona that possesses high-latitude coronal holes and a helmet streamer structure with a current sheet at the equator. The Archimedian spiral topology of the interplanetary magnetic field is reproduced along with fast and slow speed solar wind. Within this model system, we drive a CME to erupt by the introduction of a Gibson–Low magnetic flux rope that is embedded in the helmet streamer in an initial state of force imbalance. The flux rope rapidly expands, driving a very fast CME with an initial speed of in excess of 4000 km/s and slowing to a speed of nearly 2000 km/s at Earth. We find our model predicts a thin sheath around the flux rope, passing the earth in only 2 h. Shocked solar wind temperatures at 1 astronomical unit (AU) are in excess of 10 million degrees. Physics based AMR allows us to capture the structure of the CME focused on a particular Sun–Earth line with high spatial resolution given to the bow shock ahead of the flux rope.
A model study of intramolecular energy transfer in polyatomic molecular reactions

This paper reports a model study of intramolecular energy transfer in unimolecular isomerization reaction of cyclobutanone. The calculations of intramolecular energy flow were carried out using the theory of Gray and Rice as extended by Zhao and Rice. The results of the calculations are compared to those of local Lyapunov function analysis, and the agreement is found to be uniformly good.
Role of granulocyte macrophage colony-stimulating factor in host defense against pulmonary Cryptococcus neoformans infection during murine allergic bronchopulmonary mycosis.

We investigated the role of granulocyte macrophage colony-stimulating factor (GM-CSF) in host defense in a murine model of pulmonary cryptococcosis induced by intratracheal inoculation of Cryptococcus neoformans. Pulmonary C. neoformans infection of C57BL/6 mice is an established model of an allergic bronchopulmonary mycosis. Our objective was to determine whether GM-CSF regulates the pulmonary Th2 immune response in C. neoformans-infected C57BL/6 mice. Long-term pulmonary fungistasis was lost in GM-CSF knockout (GM−/−) mice, resulting in increased pulmonary burden of fungi between weeks 3 and 5. GM-CSF was required for the early influx of macrophages and CD4 and CD8 T cells into the lungs but was not required later in the infection. Lack of GM-CSF also resulted in reduced eosinophil recruitment and delayed recruitment of mononuclear cells into the airspace. Macrophages from GM+/+ mice showed numerous hallmarks of alternatively activated macrophages: higher numbers of intracellular cryptococci, YM1 crystals, and induction of CCL17. These hallmarks are absent in macrophages from GM−/− mice. Mucus-producing goblet cells were abundantly present within the bronchial epithelial layer in GM+/+ mice but not in GM−/− mice at week 5 after infection. Production of both Th1 and Th2 cytokines was impaired in the absence of GM-CSF, consistent with both reduced C. neoformans clearance and absence of allergic lung pathology.
The association of hormone replacement therapy with experimental pain responses in postmenopausal women

Considerable experimental research suggests that ovarian hormones can influence pain perception, and recent epidemiologic and clinical research suggests that exogenous hormone use may influence the prevalence and severity of clinical pain among women. However, to date no studies have examined the influence of hormone replacement therapy (HRT) on experimental pain responses and recent pain complaints among postmenopausal women. In this study, self-reported recent pain and general health were obtained, and thermal pain responses were assessed in three groups of healthy older adults: (1) women on HRT, (2) women not on HRT (No-HRT), and (3) men. Results indicated no group differences in recent pain complaints or self-reported health, but differences emerged for measures of thermal pain perception. Specifically, HRT women showed lower pain thresholds and tolerances than No-HRT women and men, and the latter two groups did not differ from each other. The potential explanations and limitations of the observed findings are discussed.
Personal narrative, performance, performativity: Two or three things I know for sure

The proliferation of personal narrative in contemporary culture and performance studies sparks both celebration and suspicion. This essay accesses and assesses current knowledge and issues about personal narrative by weaving three discourses: Dorothy Allison's performance piece Two or Three Things I Know for Sure, academic discourse, and personal narrative. From the conjoined perspectives of performance and performativity, personal narrative embodies cultural conflict about experience and identity. Performativity realizes the contextual and critical potential of the performance paradigm.
Prevalence of comorbid psychiatric illness and its impact on symptom perception, quality of life, and functional status in women with urinary incontinence.

Abstract Objective: The purpose of this study was to determine the prevalence and impact of major depression and panic disorder in women with urinary incontinence. Study Design: Participants were 218 consecutive women with urinary incontinence over a 14-month period. Major depression and panic disorder diagnoses, symptom perception, incontinence-specific quality of life, functional status, and urinary incontinence type were assessed. Results: The overall prevalence of major depression and panic disorder was 16% and 7%, respectively. In a comparison to patients with stress urinary incontinence, the odds of having major depression were 9.2 for patients with urge and 13.5 for patients with mixed urinary incontinence. Although clinically similar to patients who did not have depression, patients with depression rated their urinary incontinence as significantly more severe and had greater quality of life and functional status impairment. Conclusion: Current major depression and panic disorder are highly prevalent in women with urinary incontinence. Patients with urge and mixed urinary incontinence are significantly more likely to have coexistent psychiatric illness. Comorbid major depression significantly impacts a patient's urinary incontinence symptom reporting, incontinence-specific quality of life, and functional status. (Am J Obstet Gynecol 2002;187:80-7.)
Eosinophil granule proteins and bronchial asthma

For over 100 years, the association of eosinophils with bronchial asthma has been known. Over the past 20 years, the proteins comprising the eosinophil granule have been isolated and characterized. Four proteins are recognized and termed the major basic protein (MBP), the eosinophil peroxidase (EPO), the eosinophil-derived neurotoxin (EDN), and the eosinophil cationic protein (ECP). The activities of these proteins are reviewed with emphasis on their abilities to interact with structures in the bronchus and to reproduce features of the pathology of bronchial asthma. In addition, the relationship of these proteins to bronchial hyperreactivity, a major stigma of bronchial asthma, is discussed, and information highlighting the role of MBP is reviewed. Evidence also exists that eosinophil granule proteins may interact with the nervous system, and results showing increased vagal reactivity in an experimental animal model and the role of MBP as an allosteric muscarinic M2 receptor are presented. Finally, the effects of eosinophil granule proteins as cytostimulants on other cells including basophils, mast cells, neutrophils, platelets and alveolar macrophages are reviewed. Overall, these results indicate that eosinophil granule proteins have many abilities to alter lung function in asthma and to reproduce many of the cardinal manifestations of this disease.
The Reliability and Stability of Puff Topography Variables in Non-Daily Smokers Assessed in the Laboratory

INTRODUCTION Puff topography variables, often measured using the Clinical Research Support System device, have traditionally been studied in regular, daily smokers and have been shown to be highly stable. However, more recent research has focused on non-daily smokers as a population of interest. As such, the aim of this article was to examine puff topography stability (cross-cigarette agreement over time) and reliability (within-cigarette consistency) in non-daily smokers across six laboratory sessions. METHODS One hundred seven non-daily smokers attended six laboratory sessions over the course of 3 months. At each session, they smoked one cigarette through the Clinical Research Support System pocket, in addition to completing questionnaires about their smoking history and dependence. RESULTS Puff topography measurements were highly reliable (α values ranged from 0.87-0.95) and puff behavior was highly stable across sessions (r values ranged from 0.38-0.84). Adding sessions substantially improved reliability estimates. Aspects of puffing behavior observed in session, including puff volume, puff duration, time of puff peak, and total cigarette volume were related to level of smoke exposure, measured by expired carbon monoxide. Instability in puffing behavior was not predicted by recent or long-term smoking patterns. CONCLUSIONS Puff topography appears to be a stable and routinized aspect of smoking in non-daily smokers. The feasibility of assessing puff topography in this population is supported by the high reliabilities observed, though it should be noted that reliability greatly improved by having more than one session.
Absence of delayed lethality in mice treated with aclacinomycin A.

Two compounds that bind to or intercalate with DNA (DNA binders), e.g., adriamycin and 'dihydroxyanthracenedione', 9,10-anthracenedione, 1,4-dihydroxy-5,8-bis[[2-[(2-hydroxyethyl)-amino]ethyl]amino]-, dihydrochloride salt, consistently caused delayed lethality (20-200 days after treatment) if administered intraperitoneally (IP). Both of these agents contain para-hydroxyl groups in the ring adjacent to the quinone ring. Certain analogs of these compounds (aclacinomycin A and 'anthracenedione acetate', 9,10-anthracenedione, 1,4-bis[[2-[(2-hydroxyethyl)amino]ethyl]amino]-, diacetate (salt), which do not contain para-hydroxyl groups, did not cause delayed deaths when injected IP. The only difference in the molecular structure (other than the nature of their amine salts) between dihydroxyanthracenedione and anthracenedione acetate lies in the para-hydroxyl groups in the ring adjacent to the quinone ring. Another compound that binds to DNA, m-AMSA, which has neither the quinone function nor the para-hydroxyl groups, did not cause delayed deaths after IP administration.
Molecular cloning of telomere-binding protein gens from Stylonchia mytilis

A telomere-binding protein heterodimer of 56 kDa (alpha) and 41 kDa (beta) subunits binds specifically to Oxytricha nova telomeres. Genes encoding both subunits have been cloned previously. Here we report molecular cloning and sequence analysis of the homologous genes in Stylonychia mytilis. The derived amino acid sequences were 79% identical for the alpha subunits and 77% identical for the beta subunits. Three repeats of a Leu/Ile heptad were found in each subunit, which might be involved in heterodimer formation. A 360 amino acid region of the Stylonychia mytilis alpha subunit was found to share weak sequence similarity with human vimentin, suggesting the possibility of a relationship between telomeres and intermediate filaments.
Fistulous communications between a solitary coronary artery and the pulmonary arteries as the primary source of pulmonary blood supply in tetralogy of Fallot with pulmonary valve atresia.

Abstract A communication between the coronary and pulmonary arteries, described previously only in isolated cases1–3 and a series of 5 patients in which the communication was called an “aortopulmonary tunnel,”4 is a rare source of pulmonary arterial supply in tetralogy of Fallot with pulmonary atresia. Between 1954 and 1987, we encountered 4 patients with tetralogy of Fallot and pulmonary atresia in whom the pulmonary flow to one or both lungs was via a fistulous communication between a coronary artery and the intrapericardial pulmonary arteries. They form the basis of this report.
Spectral properties of plagioclase and pyroxene mixtures and the interpretation of lunar soil spectra

Pyroxene and plagioclase mixtures' spectral characteristics are investigated with a view to particle size and mineral proportion effects in the cases of variously proportioned labradorite/enstatite compositional mixtures. The amount of plagioclase that will allow its band to be observed in discrete absorption is particle size-dependent; plagioclase is detectable in the flattening of the pyroxene reflectance peak that lies between the 0.9 and 1.9 micron absorption bands, if sufficient plagioclase is present. Attention is given to the combined effects of mineral proportions and particle size for plagioclase/pyroxene mixtures in the case of analogs of mature and immature lunar highland soils.
SAM-modified microdisc electrode arrays (MDEAs) with functionalized carbon nanotubes

Abstract The construction of a novel voltammetric transducer employing mixed acid-chopped, oxidatively modified, single-walled carbon nanotubes (HOOC–SWNT–COOH) covalently coupled to alkane thiol self-assembled monolayers (SAMs) that were deposited onto gold microdisc electrode arrays (MDEA-Au) (1296 microdiscs, 100 μm diameter each) has been demonstrated. The chemisorption of cysteamine (CA) and 11-amino-1-undecanethiol (11-AUT) SAMs onto the MDEAs resulted in MDEA-Au|CA and MDEA-Au|11-AUT, which when conjugated with the HOOC–SWNT–COOH produced MDEA-Au|CA|SWNT and MDEA-Au|11-AUT|SWNT electrodes. Electrodes were characterized by multiple scan rate cyclic voltammetry in the presence of ferrocene monocarboxylic acid and by AFM and compared. As expected, CA modification of MDEA-Au produced a disordered film that did not alter the effective surface area of the MDEA while 11-AUT modification resulted in passivation and a 50% reduction in effective surface area. The conjugation of the SWNT to the CA-modified and the 11-AUT-modified MDEA-Au surface returned well-resolved voltammograms with highest peak currents ( I pa = 5.54 × 10 −4 A, I pc = 2.34 × 10 −4 A at 100 mV/s). The effective area of MDEA-Au|CA|SWNT was increased by 200% while that of MDEA-Au|11-AUT|SWNT was increased by 100%. AFM showed SWNTs to be vertically oriented on the CA-modified surface but to be horizontally arranged and bundled on the 11-AUT surface.
The incompressible limit in nonlinear elasticity

The incompressible limit in nonlinear elasticity is shown to fall under the theory of singular limits of quasilinear symmetric hyperbolic systems developed by Klainerman and Majda. Specifically, initial-value problems for a family of hyperelastic materials with stored energy functions $$W\left( {\frac{{\partial x}}{{\partial X}}} \right) = W_\infty \left( {\frac{{\partial x}}{{\partial X}}} \right) + \lambda ^2 w\left( {\det \frac{{\partial x}}{{\partial X}}} \right)$$ are considered, whereX andx are reference and deformed coordinates respectively. Under the assumption that the elasticity tensor $$A_{kl}^{ij} \equiv \frac{{\partial ^2 W_\infty }}{{\partial \left( {\frac{{\partial x^i }}{{\partial X^k }}} \right)\partial \left( {\frac{{\partial x^j }}{{\partial X^l }}} \right)}}$$ is positive definite near the identity matrix and thatw″(1)>0, the following results are proven for appropriate initial data:
Mesoscopic charge quantization

We study the Coulomb blockade in a chaotic quantum dot connected to a lead by a single channel at nearly perfect transmission. We take into account quantum fluctuations of the dot charge and a finite level spacing for electron states within the dot. Mesoscopic fluctuations of thermodynamic and transport properties in the Coulomb blockade regime exist at any transmission coefficient. In contrast to the previous theories, we show that by virtue of these mesoscopic fluctuations, the Coulomb blockade is not destroyed completely even at perfect transmission. The oscillatory dependence of all the observable characteristics on the gate voltage is preserved, its period is still defined by the charge of a single electron. However, phases of those oscillations at perfect transmission are random; because of the randomness, the Coulomb blockade shows up not in the averages but in the correlation functions of the fluctuating observables (e.g., capacitance or tunneling conductance). This phenomenon may be called ``mesoscopic charge quantization.''
The use of friction-stir technology to modify the surfaces of AM60B magnesium die castings

These experiments were done to evaluate the feasibility of locally modifying the surface properties of magnesium alloys with friction-stir processing. The magnesium alloy used for the study was high-pressure die-cast AM60B, nominally Mg−6Al−0.13 Mn (wt.%). Friction-stir passes were made with a translation speed of 1.7 mm/s using tool-rotation speeds of 1,250 rpm or 2,500 rpm. Stir passes with good appearance were obtained under both conditions. In some cases up to five passes were overlapped on a single bar to produce stir zones with cross-sectional dimensions of about 1.5 mm×10 mm. Metallographic examinations indicated that the stir zones were largely comprised of a magnesium solid solution with equiaxed grains on the order of 5–10 μm in size. Hardness mapping showed that the stir zones experienced increases of 16–25% compared to the as-cast metal. Room-temperature testing showed that, compared to the cast metal, the stir zones had flow stresses nearly 20% higher with about twice the tensile elongation.
Uncertain outcomes: Adjusting for misclassification in antimalarial efficacy studies

Evaluation of antimalarial efficacy is difficult because recurrent parasitaemia can be due to recrudescence or re-infection. PCR is used to differentiate between recrudescences and re-infections by comparing parasite allelic variants before and after treatment. However, PCR-corrected results are susceptible to misclassification: false positives, due to re-infection by the same variant present in the patient before treatment; and false negatives, due to variants that are present but too infrequent to be detected in the pre-treatment PCR, but are then detectable post-treatment. This paper aimed to explore factors affecting the probability of false positives and proposes a Monte Carlo uncertainty analysis to account for both types of misclassification. Higher levels of transmission intensity, increased multiplicity of infection, and limited allelic variation resulted in more false recrudescences. The uncertainty analysis exploits characteristics of study data to minimize bias in the estimate of efficacy and can be applied to areas of different transmission intensity.
Cobalamin-dependent methionine synthase: the structure of a methylcobalamin-binding fragment and implications for other B12-dependent enzymes

Cobalamin-dependent methionine synthase is a large enzyme composed of structurally and functionally distinct regions. Recent studies have begun to define the roles of several regions of the protein. In particular, the structure of a 27 kDa cobalamin-binding fragment of the enzyme from Escherichia coli has been determined by X-ray crystallography, and has revealed the motifs and interactions responsible for recognition of the cofactor. The amino acid sequences of several adenosylcobalamin-dependent enzymes, the methylmalonyl coenzyme A mutases and glutamate mutases, show homology with the cobalamin-binding region of methionine synthase and retain conserved residues that are determinants for the binding of the prosthetic group, suggesting that these mutases and methionine synthase share common three-dimensional structures.
Sanders’ Energy-Release Rate Integral for Arbitrarily Loaded Shallow Shells and Its Asymptotic Evaluation for a Cracked Cylinder

Sanders’ path-independent, energy-release rate integral I is specialized to an arbitrarily loaded shallow shell containing a stress-free void, assuming linear theory. Two forms of I are given. When the void is a crack, one form reduces to integrals over circles of vanishing radius centered at the tips and is expressible in terms of bending and stretching stressintensity factors. The other form reduces to an integral along the crack. For an elastically isotropic cylindrical shell containing a longitudinal crack and subject to a uniform bending stress at large distances from the crack, the dimensionless form of I depends on Poisson’s ratio v and a dimensionless crack length λ. When λ is small the shell is nearly flat; when λ is large the shell is very thin. An asymptotic formula is obtained for I as λ → ∞. This is done by reducing the boundary-value problem to a coupled set of singular integral equations, scaling, taking the limit as λ → ∞ to obtain inner and outer integral equations, solving the outer equations analytically, and, finally, evaluating I along the crack where the outer solutions dominate. As the evaluation of I does not require an explicit solution of the inner integral equations, an apparently intractible coupled Wiener-Hopf problem is evaded.
Synaptic vesicle diameters and synaptic cleft widths at the mouse diaphragm in Neonates and Adults

Miniature endplate potential (MEPP) amplitude distributions from adult mouse diaphragm junctions show two classes of MEPPs. The larger MEPPs form a bell-shaped distribution (bell-MEPPs) with a variance of 20-30%. The smaller MEPPs form a right-hand skew-distribution composing 1-10% of the MEPPs with a mode 1/10th (s-MEPP class) that of the bell-MEPPs. Junctions of 1-day-old neonates generate mainly s-MEPPs. The MEPP distribution gradually changes to mainly bell-MEPPs during the first 3 weeks of postnatal junctions to those of adults and reinnervated adults. We found no differences between neonates and adults in either synaptic vesicle diameter (56 nm o.d.) or in synaptic cleft widths. Synaptic vesicle diameters were the same for 'touching vesicles'. Junctions of 1-day-old neonates showed no or shallow postsynaptic folds. Postsynaptic folds were essentially developed by the third day although one-quarter of the MEPPs were of the skew-class. Assuming that vesicles are simple containers, we would expect a class of 30-nm o.d. vesicles which would generate the s-MEPP class. Since we found a smooth distribution of synaptic vesicles and no vesicles of 30 nm diameter we conclude that within the constraints of the vesicle hypothesis of transmitter release that s- and bell-MEPPs are from vesicles sized the same and that vesicle volume does not determine the amount of acetylcholine released.
Residual life predictions of corroded fuselage lap joints

Abstract This paper presents the results from a study that was carried out to determine the capability of the Equivalent Initial Flaw Size approach, referred to as Equivalent Corrosion Damage (ECD), to predict the effect that corrosion has on the residual life of fuselage lap joints. Coupons fabricated from pristine and naturally and artificially corroded lap joints were tested to failure to determine the ECD value. The stress distribution at the critical rivet hole was determined by carrying out a finite element analysis. The resulting stress correction curves were used in the afgrow crack growth rate program along with the equivalent ECD radius to predict the residual life of multi-site damage (MSD) specimens that were tested in a previous study. The analytical results were close to the experimental ones, which was not surprising given the assumption behind the ECD concept that corrosion and fatigue act sequentially. The shortcomings of the ECD approach to corrosion fatigue damage assessment and prediction are discussed along with the relationship between ECD and a new holistic approach known as the Discontinuity State Evolution Process.
Hyaluronan-CD44 Interaction Promotes c-Src-mediated Twist Signaling, MicroRNA-10b Expression, and RhoA/RhoC Up-regulation, Leading to Rho-kinase-associated Cytoskeleton Activation and Breast Tumor Cell Invasion

Dysregulation of microRNAs is observed in many cancers, including breast cancer. In particular, miR-10b appears to play an important role in tumor cell invasion and breast cancer progression. In this study, we investigated hyaluronan (HA)-induced CD44 (a primary HA receptor) interaction with c-Src kinase and the transcriptional factor, Twist, in breast tumor cells (MDA-MB-231 cells). Our results indicate that HA binding to CD44 promotes c-Src kinase activation, which, in turn, increases Twist phosphorylation, leading to the nuclear translocation of Twist and transcriptional activation. Further analyses reveal that miR-10b is controlled by an upstream promoter containing the Twist binding site(s), whereas ChIP assays demonstrate that stimulation of miR-10b expression by HA/CD44-activated c-Src is Twist-dependent in breast tumor cells. This process results in the reduction of a tumor suppressor protein (HOXD10), RhoA/RhoC up-regulation, Rho-kinase (ROK) activation, and breast tumor cell invasion. Treatment of MDA-MB-231 cells with PP2 (a c-Src inhibitor) or Twist-specific siRNAs effectively blocks HA-mediated Twist signaling events, abrogates miR-10b production, and increases HOXD10 expression. Subsequently, this c-Src/Twist signaling inhibition causes down-regulation of RhoA/RhoC expression and impairment of ROK-regulated cytoskeleton function (e.g. tumor cell invasion). To further evaluate the role of miR-10b in RhoGTPase signaling, MDA-MB-231 cells were also transfected with a specific anti-miR-10b inhibitor in order to silence miR-10b expression and block its target functions. Our results demonstrate that anti-miR-10b inhibitor not only enhances HOXD10 expression but also abrogates HA/CD44-mediated tumor cell behaviors in breast tumor cells. Taken together, these findings indicate that the HA-induced CD44 interaction with c-Src-activated Twist plays a pivotal role in miR-10b production, leading to the down-regulation of tumor suppressor protein (HOXD10), RhoGTPase-ROK activation, and tumor cell invasion. All of these events are critical prerequisite steps for the acquisition of metastatic properties by human breast cancer cells.
Plasma and red blood cell zinc in cystic fibrosis.

The objectives of this study were to measure plasma and red blood cell (RBC) zinc concentrations in patients with cystic fibrosis (CF), and examine their relationship to nutritional status and pulmonary function. Plasma and RBC zinc levels were compared in 53 CF patients ranging in age from 0.5-46 years. Their relationships to weight (% ideal weight) and forced expired volume in 1 sec (FEV(1)) (% predicted value) were examined. After excluding improperly handled specimens, RBC zinc levels in 51 patients and plasma zinc concentrations in 40 patients were included for analysis. Sixteen of 51 (31%) patients had low RBC zinc levels compared to 4 of 40 (10%) with low plasma zinc concentrations (P < 0.01). Thirteen of 38 patients (34%) in whom both values were obtained had low RBC zinc concentrations compared to 4 of 38 (11%) with low plasma zinc levels (P < 0.022). Neither low RBC nor plasma zinc levels correlated with nutritional status or lung function. In conclusion, about one third of patients with CF had low RBC zinc levels. Plasma zinc concentrations may not adequately reflect overall zinc status. This deficiency did not appear to be related to either nutritional status or lung function. The significance of low RBC zinc in CF is unknown.
Optimizing the synthesis and properties of Al-modified anatase catalyst supports by statistical experimental design

The important variables in the synthesis of stable, high surface area, aluminum-modified anatase TiO2 catalyst supports were identified and optimized using statistically designed experiments (DOEs). The first DOE examined ten variables at two levels and a second DOE studied eight variables at three levels. Equations were developed to predict the conditions to obtain the highest surface area and pore volume at the desired pore diameter and predict the pore diameter range that may be obtained. Confirmation trials closely matched predicted surface areas, pore volumes, and pore diameters in all but one trial. Rinsing order (before or after calcination) was the most significant factor. Other important factors were calcination temperature, mol% aluminum, and water addition speed. The results of this study demonstrate (a) the power of DOEs in identifying and controlling synthesis variables in relatively few experiments and (b) how analysis of factor effects can provide insight into the formation mechanism.
Antibody testing and counseling of dental patients at risk for human immunodeficiency virus (HIV) infection and associated clinical findings

Two hundred six dental patients were tested between 1985 and 1987 for antibodies to human immunodeficiency virus (HIV) when a review of their medical histories revealed a high risk for infection. Serologic results are correlated with soft tissue and osseous findings recorded during routine head and neck and radiographic examination. Counseling recommendations for use in association with testing are outlined. A more active role for the dentist as a preventive agent is advocated to combat the spread of acquired immunodeficiency syndrome (AIDS).