cssi/SciSciGPT-SciSciNet huggingface dataset:
Modeling Biofilm Processes Using the Immersed Boundary Method

Biofilm processes are of interest to researchers in a variety of fields including bioremediation, oil recovery, wastewater treatment, medicine, and dentistry. In this paper we describe how this complex, dynamic, fluid?structure interaction can be modeled successfully using theimmersed boundary method. The model presented here includes the coupling of hydrodynamics; substrate reaction, diffusion, and convection; as well as the chemotactic response of swimming microbes. Cell?cell aggregation and cell?substratum adhesion are modeled by generating appropriate binding forces between discrete representations of organisms that may hold them together, or if fluid stresses are large, may yield and release the organisms. In this paper, we show two-dimensional numerical simulations to demonstrate several different types of scenarios that may be modeled using immersed boundary methods. These simulations indicate the variety of different phenomena one might expect in biofilm processes.
Changes in salt intake after abdominal vagotomy: evidence for hepatic sodium receptors.

Abstract Several reports have suggested that the mammalian liver contains neural receptors, innervated by the vagus nerve, that monitor the sodium concentration and osmolarity of the portal circulation. These reports have been concerned primarily with either the neurophysiological identification of these receptors or their role in the short term control of urine output. Inasmuch as relatively little is known about the role of these receptors to consummatory behavior, we investigated the effects of hepatic vagotomy in rats on sodium intake as well as on sodium output. Hepatic vagotomized (HV) rats drank less NaCl solution (0.03, 0.1, 0.3M) in 24 hr during a two-bottle test with water than sham operated rats. Comparable differences in the intakes of either water, KCl or glucose solutions were not found. The two groups of rats did not differ in their intakes of water or 0.3M NaCl after an injection of either an osmotic load (IP, 2 M NaCl, 1% BW), deoxycorticosterone acetate (SC, 5 mg) along with furosemide (SC, 10 mg), or after 10 days of sodium deprivation. Urinary sodium output was reduced in HV rats during sodium deprivation but not when the rats had adequate levels of sodium in their diet. Because circadian patterns of water and food intake as well as body weight growth of hepatic vagotomized rats were similar to those of control rats, general malaise due to surgery and generalized deficits in motivation were ruled out as explanations for the depressed daily drinking of NaCl solutions. These findings support the existence of hepatic sodium receptors and their possible involvement to the control of sodium regulation.
Structural studies of vacuolar plasmepsins

Plasmepsins (PMs) are pepsin-like aspartic proteases present in different species of parasite Plasmodium. Four Plasmodium spp. (P. vivax, P. ovale, P. malariae, and the most lethal P. falciparum) are mainly responsible for causing human malaria that affects millions worldwide. Due to the complexity and rate of parasite mutation coupled with regional variations, and the emergence of P. falciparum strains which are resistant to antimalarial agents such as chloroquine and sulfadoxine/pyrimethamine, there is constant pressure to find new and lasting chemotherapeutic drug therapies. Since many proteases represent therapeutic targets and PMs have been shown to play an important role in the survival of parasite, these enzymes have recently been identified as promising targets for the development of novel antimalarial drugs. The genome of P. falciparum encodes 10 PMs (PMI, PMII, PMIV-X and histo-aspartic protease (HAP)), 4 of which (PMI, PMII, PMIV and HAP) reside within the food vacuole, are directly involved in degradation of human hemoglobin, and share 50-79% amino acid sequence identity. This review focuses on structural studies of only these four enzymes, including their orthologs in other Plasmodium spp.. Almost all original crystallographic studies were performed with PMII, but more recent work on PMIV, PMI, and HAP resulted in a more complete picture of the structure-function relationship of vacuolar PMs. Many structures of inhibitor complexes of vacuolar plasmepsins, as well as their zymogens, have been reported in the last 15 years. Information gained by such studies will be helpful for the development of better inhibitors that could become a new class of potent antimalarial drugs. This article is part of a Special Issue entitled: Proteolysis 50 years after the discovery of lysosome.
Development of the Drosophila retina, a neurocrystalline lattice

Pattern formation in the Drosophila retina proceeds by the recruitment of cells, along a morphogenetic front, into a lattice. At the advancing front, marked by a dorso-ventral furrow in the eye imaginal disc, cells are organized into ommatidial precursors, each containing cells destined to become photoreceptors 2, 3, 4, 5, and 8. Behind the front, a mitotic wave produces photoreceptors 1, 6, and 7, plus the remaining cells needed to complete the ommatidia. During the third larval instar, the front sweeps anteriorly across the eye disc, leaving a highly ordered pattern in its wake. Preceding the dorso-ventral furrow is a groove that bisects the eye disc into dorsal and ventral halves and presumably plays a role in establishing the equatorial symmetry line. Cell lineage plays little role in pattern formation in the eye. Genetic mosaics show that the cells of each ommatidium are not derived from a single mother cell; the cells appear to be recruited at random at the morphogenetic front. Similarly, the mirror symmetry above and below the equator is not established by a clonal mechanism; a single clone can contribute cells to ommatidia on both sides of the equator.
Correction of helical CT attenuation values with wide beam collimation: in vitro test with urinary calculi.

Abstract Rationale and Objectives Urinary calculi are now commonly detected with helical computed tomography (CT), and it has been proposed that stone composition can be determined from CT attenuation values. However, typical scans are made with a beam collimation of 5 mm or more, resulting in volume averaging and reduction in accuracy of attenuation measurement. The authors tested a model for correction of errors in attenuation values, even at section widths larger than the width of the object. Materials and Methods Human urinary stones were scanned with helical CT at different beam collimation widths. A computer model was used to predict the effect of beam width and stone size on accuracy of measured attenuation. Results At 3-mm collimation, the model corrected the attenuation readings with an underestimation of 12% ± 1 (compared with values at 1-mm collimation; 127 stones; diameters of 1.7–11.3 mm). With attenuation measured at 10-mm collimation, the model underestimated the true value by 34% ± 3 (103 stones), with a significant negative correlation with stone diameter on magnitude of error (diameters of 3.0–11.3 mm). Correlation of data from patient scans with subsequent in vitro scanning of the same stones confirmed the validity of the model, but corrected in vivo scans consistently yielded lower values for the stones than in vitro. Conclusion Volume averaging effects on attenuation in helical CT are predictable in vitro for urinary calculi—and presumably for other roughly spherical structures—as long as section width does not excessively exceed the diameter of the structure.
Relationships of occupational and non-occupational physical activity to abdominal obesity.

Physically active occupations may protect against the risk of abdominal obesity. This study assessed the interaction between non-occupational physical activity (NOA) (leisure-time, transport and domestic activity) and occupational activity (OA) in relation to abdominal obesity. A total of 3539 adults over the age of 20, with no work limitations, employed in one of the 17 occupations classified as low OA (LOA) or high OA (HOA) were identified in the 1999–2004 National Health and Nutrition Examination Survey. Waist circumference (WC) was used to categorize individuals into either non-obese or abdominally obese (WC>88 cm in women and >102 cm in men) categories. NOA was divided into three categories based upon physical activity guidelines: (1) no NOA; (2) insufficient NOA; and (3) sufficient NOA. Logistic regression was used to examine possible associations between NOA, OA and abdominal obesity. In those who are sedentary outside of work, a high-activity occupation reduces the odds risk ratio of being categorized with abdominal obesity to 0.37 in comparison with those who work in low-activity occupations. For people working in low-activity occupations, there was a clear association with activity outside of work and the odds risk ratio of being categorized with abdominal obesity. In these adults, a reduced odds ratio was found only among those who met the physical activity guidelines through NOA (odds ratio=0.55; 95% confidence interval (CI)=0.40–0.75). HOA is associated with a reduced risk of abdominal obesity. Thus, it is important to include OA in studies seeking to understand the association between physical activity and abdominal adiposity.
Specific binding of covalently cross-linked mouse nerve growth factor to responsive peripheral neurons.

Abstract The binding characteristics of [ 125 I]nerve growth factor, covalently cross-linked with dimethyl suberimidate, to chick embryonic dorsal root ganglia are indistinguishable from the iodinated native hormone. Both show non-saturability, non-linear Scatchard plots and acceleration of dissociation of hormone-receptor complexes by native hormone which is reflected in the binding constants calculated. These results demonstrate that dimerization of the native hormone at the receptor is not responsible for the negatively cooperative behavior observed for native nerve growth factor. Further, experiments with amino-silylated glass tubes also eliminate interaction between hormone and reaction vessel as an explanation of the non-saturable and multiple affinity properties of the observed binding.
Ligand-activated Pregnane X Receptor Interferes with HNF-4 Signaling by Targeting a Common Coactivator PGC-1α FUNCTIONAL IMPLICATIONS IN HEPATIC CHOLESTEROL AND GLUCOSE METABOLISM

Previous studies show that feedback inhibition of bile acid production by bile acids is mediated by multiple mechanisms, including activation of pregnane X receptor (PXR). Consistent with these studies, the antibiotic rifampicin, a ligand for human PXR, reduces hepatic bile acid levels in cholestasis patients. To delineate the mechanisms underlying PXR-mediated suppression of bile acid biosynthesis, we examined the functional cross-talk between human PXR and HNF-4, a key hepatic activator of genes involved in bile acid biosynthesis including the cholesterol 7-α hydroxylase (CYP7A1) and sterol 12-α hydroxylase (CYP8B1) genes. Treatment with rifampicin resulted in repression of endogenous human CYP7A1 expression in HepG2 cells that was reversed by PXR small interfering RNA. The coactivator PGC-1 enhanced transcriptional activity of HNF-4, and this enhancement was suppressed by rifampicin-activated PXR. Endogenous PGC-1 from mouse liver extracts bound to PXR, and recombinant PGC-1 directly interacted with both PXR and HNF-4 in vitro. Rifampicin-dependent interaction of PXR with PGC-1 was shown in cells by coimmunoprecipitation, and intranuclear localization studies using confocal microscopy provided further evidence for this interaction. In chromatin immunoprecipitation studies, rifampicin treatment did not inhibit HNF-4 binding to the native promoters of CYP7A1 and CYP8B1 but resulted in dissociation of PGC-1 and concomitant gene repression. Most interestingly, these rifampicin effects were also observed in the phosphoenolpyruvate carboxykinase gene that contains a functional HNF-4-binding site and is central to hepatic gluconeogenesis. Our study suggests that ligand-activated PXR interferes with HNF-4 signaling by targeting the common coactivator PGC-1, which underlies physiologically relevant inhibitory cross-talk between drug metabolism and cholesterol/glucose metabolism.
The Sexual Double Standard and Gender Differences in Predictors of Perceptions of Adult-Teen Sexual Relationships

We study gender differences and the effects of adult’s gender, an authority gap, and an age gap on university students’ perceptions of adult-teen sexual relationships. We specifically examine: the adult’s criminality, damage to the teen’s reputation, and emotional damage to the teen. We use a sample of 2,871 students from a Southwestern university in the U.S. who judged vignettes describing an adult-teen encounter. OLS regression demonstrated that women judged the scenarios more negatively than men. Further analyses found relationships between the experimental variables and each dependent variable and interactions by respondent’s gender and among the experimental variables. Results demonstrate a sexual double standard and highlight respondent’s gender, the age gap, and the authority context for perceptions of adult-teen relationships.
Does Emotion Dysregulation Mediate the Association Between Sluggish Cognitive Tempo and College Students’ Social Impairment?

Objective: Studies demonstrate an association between sluggish cognitive tempo (SCT) and social impairment, although no studies have tested possible mechanisms of this association. This study aimed to (a) examine SCT in relation to college students’ social functioning; (b) test if SCT is significantly associated with emotion dysregulation beyond depressive, anxious, and ADHD symptoms; and (c) test if emotion dysregulation mediates the association between SCT symptoms and social impairment. Method: College students (N = 158) completed measures of psychopathology symptoms, emotion dysregulation, and social functioning. Results: Participants with elevated SCT (12%) had higher ADHD, depressive, and anxious symptoms in addition to poorer emotion regulation and social adjustment than participants without elevated SCT. Above and beyond other psychopathologies, SCT was significantly associated with social impairment but not general interpersonal functioning. SCT was also associated with emotion dysregulation, eve...
Melanotic craniopharyngioma: a report of two cases

We report a 74-year-old woman and a 50-year-old woman with similar histories of headache and visual disturbance who were found to have adamantinomatous craniopharyngiomas which contained melanin pigment. This finding was confirmed by the Masson Fontana method and ultrastructural studies. These are only the second and third cases reported describing melanin pigment within a craniopharyngioma. The finding of melanin in craniopharyngiomas attests to their similarities with odontogenic tumors of the jaw, which can also contain melanin pigment and also supports the hypothesis that the histogenesis of these neoplasms derives from the vestiges of Rathke's pouch epithelium.
Identification of electrostatic interaction sites between the regulatory and catalytic subunits of cyclic AMP‐dependent protein kinase

Two classes of molecules inhibit the catalytic subunit (C) of the cyclic AMP-dependent protein kinase (cAPK), the heat-stable protein kinase inhibitors (PKIs) and the regulatory (R) subunits. Basic sites on C, previously identified as important for R/C interaction in yeast TPK1 and corresponding to Lys213, Lys217, and Lys189 in murine C alpha, were replaced with either Ala or Thr and characterized for their kinetic properties and ability to interact with RI and PKI. rC(K213A) and rC(K217A) were both defective in forming holoenzyme with RI but were inhibited readily with PKI. This contrasts with rC(R133A), which is defective in binding PKI but not RI (Wen & Taylor, 1994). Thus, the C-subunit employs two distinct electrostatic surfaces to achieve high-affinity binding with these two types of inhibitory molecules even though all inhibitors share a common consensus site that occupies the active site cleft. Unlike TPK1, mutation of Lys189 had no effect. The mutant C subunits that were defective in binding RI, rC(K213A) and rC(K217A), were then paired with three RI mutants, rRI(D140A), rRI(E143A), and rRI(D258A), shown previously to be defective in recognition of C. Although the mutations at Asp140 and Asp258 in RI were additive with respect to the C mutations. rC(K213A) and rRI(E143A) were compensatory, thus identifying a specific electrostatic interaction site between RI and C. The results are discussed in terms of the RI and C crystal structures and the sequence homology between the yeast and mammalian enzymes.
Inhibition of cADP-Ribose Formation Produces Vasodilation in Bovine Coronary Arteries

cADP-ribose (cADPR) induces the release of Ca(2+) from the intracellular stores of coronary artery smooth muscle cells. However, little is known about the role of cADPR-mediated intracellular Ca(2+) release in the control of vascular tone. The present study examined the effects of nicotinamide, a specific inhibitor of ADP-ribosylcyclase, on the vascular tone of bovine coronary arteries. A bovine coronary artery homogenate stimulated the conversion of nicotinamide guanine dinucleotide into cGDP-ribose, which is a measure of ADP-ribosylcyclase activity. Nicotinamide significantly inhibited the formation of cGDP-ribose in a concentration-dependent manner: at a concentration of 10 mmol/L, it reduced the conversion rate from 3.34+/-0.11 nmol. min(-1). mg(-1) of protein in control cells to 1.42+/-0.11 nmol. min(-1). mg(-1) of protein in treated cells, a 58% reduction. In U46619-precontracted coronary artery rings, nicotinamide produced concentration-dependent relaxation. Complete relaxation with nicotinamide occurred at a dose of 8 mmol/L; the median inhibitory concentration (IC(50)) was 1.7 mmol/L. In the presence of a cell membrane-permeant cADPR antagonist, 8-bromo-cADPR, nicotinamide-induced vasorelaxation was markedly attenuated. Pretreatment of the arterial rings with ryanodine (50 micromol/L) significantly blunted the vasorelaxation response to nicotinamide. However, iloprost- and adenosine-induced vasorelaxation was not altered by 8-bromo-cADPR. Moreover, nicotinamide significantly attenuated KCl- or Bay K8644-induced vasoconstriction by 60% and 70%, respectively. These results suggest that the inhibition of cADPR formation by nicotinamide produces vasorelaxation and blunts KCl- and Bay K8644-induced vasoconstriction in coronary arteries and that the cADPR-mediated Ca(2+) signaling pathway plays a role in the control of vascular tone in coronary circulation.
Dissociation of Hepatic Messenger Ribonucleic AcidS14 Levels and Nuclear Transcriptional Rates in Suckling Rats

The messenger RNA (mRNA) coding for the rat hepatic protein spot 14(S14) (mol wt 17,000; pI 4.9) is rapidly responsive to T3 and carbohydrate administration in the adult animal. In 15-day-old suckling rats, the level of expression is 200-fold less than in 60-day-old chow-fed animals. However, the relative transcriptional activity of the S14 gene is only 30% higher in the 60-day-old rat than in the 15-day-old animal. Although T3 induces a 100-fold increase in mRNAS14 in 15-dayold animals, there was only a 17% increase in the S14 gene transcriptional activity. These results indicate that the hormonal and developmental regulation of the S14 gene in liver appears to be predominantly directed at the posttranscriptional level. (Endocrinology 118; 1892–1896, 1986)
New structural and mechanistic insight into the A-rule and the instructional and non-instructional behavior of DNA photoproducts and other lesions

Abstract The A-rule in mutagenesis was originally proposed to explain the preponderance of X→T mutations observed for abasic sites and UV damaged sites. It was deduced that when a polymerase was faced with a non-instructional lesion, typified by an abasic site, it would preferentially incorporate an A. In the absence of any other compelling explanation, any lesion causing an X→T mutation has often been classified as non-instructional to account for its apparent lack of instructional ability. The A-rule and the classification of lesions as non-instructional were formulated before the active sites of any polymerases or the mechanism by which they synthesized DNA were known. Since then, much structural and kinetic data on DNA polymerases has emerged to suggest mechanistic explanations for the A-rule and the instructive and non-instructive behavior of lesions such as cis–syn dimers. Polymerases involved in the replication of undamaged DNA have highly constrained active sites that evolved to only accommodate the templating base and the complementary nucleotide and as a result are relatively intolerant of modifications that alter the size and shape of the nascent base pair. On the other hand, DNA damage bypass polymerases have much more open and less constrained active sites, which are much more tolerant of modifications. An otherwise instructional lesion would become non-instructional if it were unable to fit into the active site, and thereby behave transiently like an abasic site, leading to the insertion of whichever nucleotide is favored by the polymerase, generally an A. In this review, what is known about the active sites and mechanisms of replicative and DNA damage bypass polymerases will be discussed with regard to the A-rule and non-instructive behavior of lesions, typified by dipyrimidine photoproducts.
Characteristics of Ovalbumin Gel Layer Formed on Ceramic Microfiltration Membranes

Ovalbumin solution, which is known to form a gel layer on membrane surfaces, was filtrated in a cross-flow mode using ceramic microfiltration membranes. The influences of pH and ionic strength of the ovalbumin solution on the properties of the gel layer and membrane permeability were studied.At a pH near the isoelectric point of the ovalbumin solution, both the permeate flux and ovalbumin rejection showed the lowest value. The cohesion force acting among ovalbumin molecules became strongest because the electrostatic repulsion force among the molecules was weakened, and then the gel layer was tightly adsorbed onto the membrane surface. Therefore, the membrane permeate flux obtained at the pH of the isoelectric point was smaller than that obtained at the other pH. The ovalbumin rejection increased at the other pH, except for the isoelectric point, because of the electrostatic repulsion of the ovalbumin gel layer formed on the membrane surface. The influence of electric charge was also recognized in the case of the filtration of sodium L-glutamate solution using the ovalbumin gel layer.When the ovalbumin solution was filtered with a high ionic strength, the permeate flux and the ovalbumin rejection were almost constant, independent of the solution pH.The molecular weight cut-off values of the ovalbumin gel layer were about 200,000–300,000 as self-rejecting dynamic membranes.The specific resistance of the ovalbumin gel layer obtained in dead-end filtration increased in pH near the isoelectric point and with increasing ionic strength of the feed solution. This tendency of the specific resistances was in good agreement with the behavior of the permeate flux of the ovalbumin solution.
Interdependence and Instability: Do the Levels of Output in the Advanced Capitalist Countries Increasingly Move Up and Down Together?

This paper examines the hypothesis that the degree of synchronization of movements of output in the advanced capitalist countries increased in the 1970s relative to earlier years. Two types of statistical tests are employed: one set of tests focuses on the relations between pairs of economies, measuring the frequency of their joint upward or downward movement; the other set of tests, based on multiple regression analysis, examines relations among several economies. The tests offer considerable-but not unqualified-support for the basic hypothesis, and they also provide some insights on possible causes of increased synchronization. The paper notes that, while increased synchronization is one aspect of growing international interdependence, synchronization is affected differently by different aspects of the economic ties among nations. The paper concludes with the suggestion that there is a connection between the synchronization phenomenon and the nature of the current economic crisis.
Stomatal Movements, Frequencies, and Resistances in Two Maize Varieties Differing in Photosynthetic Capacity

The stomatal characteristics of two maize varieties previously found to differ in rates of net photosynthesis were examined in a controlled environment. Measurements with a ventilated diffusion porometer showed that one variety exhibited a pronounced and the other a weak periodicity in stomatal resistance of the adaxial epidermis. At equal illumination the stomatal resistance of the adaxial epidermis decreased from upper to lower leaves, while the resistance of the abaxial epidermis changed in the opposite manner. Stomata on the adaxial and abaxial surfaces of maize leaves exhibited random, not compensatory, movements in a constant environment. The variety with the lesser stomatal frequency and higher total leaf resistance to water loss had nevertheless fastsr net photosynthesis than the variety with the greater stomatal frequency, demonstrating the importance of the so-called mesophyll resistance.
Diurnal radiance patterns of finite and semi-infinite clouds in observations of cloud fields

Abstract One of the important radiative effects of cloud Shape is to modify diurnal radiance patterns observed from satellites. Theory predicts a diurnal radiance pattern nearly symmetric about local noon for both semi-infinite and finite clouds situated on the equator at the equinox with a satellite directly overhead. For a geostationary satellite (SMS-1) located to the west of the cloud, the semi-infinite cloud still products a pattern nearly symmetric about local noon while finite cubic clouds produce a distinctly different pattern which peaks during the afternoon. Simulated diurnal satellite observations of a finite cubic and semi-infinite cloud were compared with actual diurnal satellite observations of cloud fields with cloud cover varying from less than 30% to greater than 90%. The results for 4 n mi resolution data from the two observed cloud fields demonstrate that the diurnal radiance patterns of both semi-infinite and finite clouds exist in satellite observations. Degrading the resolution to 16...
An Estimate of Global Absolute Dynamic Topography

The absolute dynamic topography of the world ocean is estimated from the largest scales to a short-wavelength cutoff of about 6700 km for the period July through September, 1978. The data base consisted of the time-averaged sea-surface topography determined by Seasat and geoid estimates made at the Goddard Space Flight Center. The issues are those of accuracy and resolution. Use of the altimetric surface as a geoid estimate beyond the short-wavelength cutoff reduces the spectral leakage in the estimated dynamic topography from erroneous small-scale geoid estimates without contaminating the low wavenumbers. Comparison of the result with a similarly filtered version of Levitus' (1982) historical average dynamic topography shows good qualitative agreement. There is quantitative disagreement, but it is within the estimated errors of both methods of calculation.
Random partitioning of cytoplasmic organelles at cell division: The effect of organelle and cell volume

When a cell divides, some cytoplasmic organelles may be partitioned randomly between the daughters. The number of organelles in each daughter is usually calculated from the binomial distribution, which assumes that the organelles occupy zero volume. We developed equations to predict numerical partitioning taking the volume of the organelles and of the cell into account. The effect of large organelle volume is that daughter cells receive equal or nearly equal numbers of organelles more often than predicted by the binomial distribution. However, numerical solutions show that volume effects are very small unless the number of organelles is very small or they occupy more than about 50% of the available cell volume.
Vibronic Splitting and Zeeman Effect in Octahedral Molecules: Odd-Electron Systems

A theoretical investigation of the low-field vibronic Zeeman effect in octahedral molecules with odd-electron central atoms is presented. Such systems are of interest because the vibronic $g$ values differ from those of the parent electronic level and provide a means of studying the vibronic interaction. Only ${\ensuremath{\Gamma}}_{8}$ parent electronic states are of interest, and the vibronic multiplet splitting is derived for these states in terms of a minimum number (two) of vibronic interaction parameters. The Zeeman splitting of the vibronic multiplet is determined in terms of the parent electronic Zeeman effect, and for ${\ensuremath{\Gamma}}_{8}$ vibronic states, in addition, in terms of the vibronic interaction parameters. It is shown that that in spite of anisotropy in the Zeeman splitting of ${\ensuremath{\Gamma}}_{8}$ electronic or vibronic levels and the tumbling of free molecules, the observed Zeeman splitting should appear as four resolvable bands or lines except in certain limiting cases, but in all cases the information on $g$ values can in principle be determined from experiment.
Optimal stochastic control of nonlinear systems

An algorithm is proposed for the feedback control of nonlinear systems, the observations of which are corrupted with noise of unknown statistics. The feedback loop contains a nonlinear Kalman filter, which produces sequential least-square estimates of the state of the system, and a controller designed to minimize an instantaneous performance criterion based on the state estimates. The scheme requires the on-line integration of n(n + 3)/2 differential equations, where n is the number of unknown states and parameters. The scheme is applied to the feedback control of a CSTR with a first-order exothermic reaction the temperature measurements of which are corrupted with random noise.
Annular/Stratified Internal Condensing Flows in Millimeter to Micrometer Scale Ducts

This paper presents computational simulations for internal condensing flows over a range of tube/channel geometries — ranging from one micro-meter to several millimeters in hydraulic diameters. Over the mm-scale, three sets of condensing flow results are presented that are obtained from: (i) full computational fluid dynamics (CFD) based steady simulations, (ii) quasi-1D steady simulations that employ solutions of singular non-linear ordinary differential equations, and (iii) experiments involving partially and fully condensing gravity driven flows of FC-72 vapor. These results are shown to be self-consistent and in agreement with one another. The paper demonstrates the existence of a unique solution for the strictly steady equations for gravity and shear driven flows. This paper also develops useful correlations for shear driven and gravity driven annular stratified internal condensing flows (covering some refrigerants and common operating conditions of interest). A useful map that marks various transitions between gravity and shear dominated annular stratified flows is also presented. For the micro-meter scale condensers, computations indentify a critical diameter condition (in non-dimensional terms), below which the flows are insensitive to the orientation of the gravity vector as the condensate is always shear driven. Large pressure drop, importance of surface tension, and vapor compressibility for μm-scale flows are also discussed. With the help of comparisons with 0g flows, the paper also discusses effects of transverse gravity on the solutions for horizontal channel flows.Copyright © 2009 by ASME
The scattering of certain Yang-Mills fields

The Yang-Mills fields considered by us in an earlier paper are asymptotically non-interacting. Also any free field is an incoming field for some Yang-Mills field.
Segregation of Minorities in the Metropolis: Two Decades of Change

Data from Census 2000 show that black-white segregation declined modestly at the national level after 1980, while Hispanic and Asian segregation rose in most metropolitan areas. Changes that may have produced greater changes for blacks proved to have insignificant effects: there was no net shift of the black population toward less-segregated areas, segregation at the metropolitan level did not decline more in areas where the incomes of blacks came closer to the incomes of whites over time, and the emergence of more multiethnic metropolises had no impact. As in the past, declines were centered in the South and West and in areas with smaller black populations. Increases in Hispanic and Asian segregation in individual metropolitan areas were counterbalanced by a net movement of these two groups toward areas of lower segregation. These increases were associated especially with the more rapid growth in the Hispanic and Asian populations. Hispanic segregation increased more in regions where group members had declining incomes relative to the incomes of whites and included a growing share of immigrants.
Assessment Methodology, Context, and Empowerment: The ACE Model of Skill Development.

The assessment, context, and empowerment (ACE) model is offered as a framework for designing a course in which students and instructors work as partners to develop students' skills. The use of this model provides students with targeted opportunities for practice on multiple skill dimensions while linking the dimensions to relevant contexts. In a triangular procedure, students receive developmental feedback from three sources: themselves, their peers, and their instructor. Procedures for student empowerment, special responsibilities for the instructor, and lessons learned from using this approach are outlined.
How I treat mixed-phenotype acute leukemia.

Mixed-phenotype acute leukemia (MPAL) encompasses a heterogeneous group of rare leukemias in which assigning a single lineage of origin is not possible. A variety of different terms and classification systems have been used historically to describe this entity. MPAL is currently defined by a limited set of lineage-specific markers proposed in the 2008 World Health Organization monograph on classification of tumors of hematopoietic and lymphoid tissues. In adult patients, MPAL is characterized by relative therapeutic resistance that may be attributed in part to the high proportion of patients with adverse cytogenetic abnormalities. No prospective, controlled trials exist to guide therapy. The limited available data suggest that an “acute lymphoblastic leukemia–like” regimen followed by allogeneic stem-cell transplant may be advisable; addition of a tyrosine kinase inhibitor in patients with t(9;22) translocation is recommended. The role of immunophenotypic and genetic markers in guiding chemotherapy choice and postremission strategy, as well as the utility of targeted therapies in non–Ph-positive MPALs is unknown.
Performance analysis of critical time points for moving object prediction in dynamic environments (PRIDE)

We have developed PRIDE (Prediction In Dynamic Environments), a hierarchical multi-resolutional framework for moving object prediction that incorporates multiple prediction algorithms into a single, unifying framework. PRIDE incorporates two approaches for the prediction of the future location of moving objects at various levels of resolution at the frequency and level of abstraction necessary for planners at different levels within the hierarchy. These approaches, termed long-term (LT) and short-term (ST) predictions, respectively, are based on situation recognition and vehicle models for moving object prediction using sensor data. Our recent efforts have demonstrated the ability to use the results of the short-term prediction algorithms to strengthen/weaken the estimates of the long-term prediction algorithms. Based on previous experiments, we have found that the short-term prediction algorithms perform best when predicting on the order of a few seconds into the future and that the longer-term prediction algorithms are best at predicting on the order of several seconds into the future. In this paper, we explore the time window in which both the short-term and the long-term prediction algorithms provide reasonable results. Additionally, we describe a methodology by which we can determine the time point at which the short-term prediction algorithm no longer provides results within an acceptable predefined error threshold. We provide experimental results in an autonomous on-road driving scenario using AutoSim, a high-fidelity simulation tool that models details about road networks, including individual lanes, lane markings, intersections, legal intersection traversability, etc.
Pathological specimens of the kidney examined by Richard Bright.

Richard Bright achieved his deserved place in the annals of medical history largely through his descriptions of chronic renal diseases which collectively came to be known as "Bright's disease." It is therefore remarkable that the entire body of literature relating to renal disease generated by Bright contains only five plates illustrating the diseased kidneys of eight of his patients examined at post mortem. These illustrations which appeared in the first volume of Reports of medical cases selected with a view of illustrating the symptoms and cure of diseases by a reference to morbid anatomy [1] in 1827, are masterpieces of medical illustration. Although, to be sure, Bright possessed a more than ample ability to describe what he saw with great accuracy and attention to detail, his descriptions abound with attention to color. As Peitzman has phrased it, "He seems to strain his effort to transmit verbally the lines and tone he saw in the fresh necropsy specimens [2]." Bright saw "small whitish or yellow granules projecting with red intervening spaces" and thinned cortical regions "of a grayish drab mixed with purple." We know that Bright himself was a consummate artist, for the impressive engravings which appear in his first book "Travels from Vienna through lower Hungary" [31 each bears the small caption "sketched by R. B." Not content with his own talents as an illustrator, Bright employed the talents of one Frederick Richard Say (died 1860), a portrait painter of distinction [4] who painted the portrait of Richard Bright which now hangs in the Royal College of Physicians of London [5]. (Say's father, William, engraved the plates for the illustrations in the Reports of medical cases which were then hand-colored, probably by a skilled artist.) In order to achieve the most poignant reproductions of his post-mortem material, Bright was probably required to bring Say to the autopsy room whenever a specimen of interest arose. Say presumably produced a water color image of the specimen on the spot which was subsequently copied by the engraver. Not more than 250 copies of the first volume of the Reports of medical cases were sold; the book was extremely costly owing to the high quality of paper used, the large size of the volume and the hand coloring of the plates. The ledgers of the publisher (Longman), show that the remaining stock was destroyed in a fire of 1861 [2]. The rarity of the volume and the high quality of the publication have made it a highly desirable item for libraries
Kritisches und Experimentelles zur Deutung der Potentialschwankungen des Elektrocorticogramms

1. Das Elektrocorticogramm (ECG) einer durch schichtweise Thermokoagulation (imchronischen Versuch) auf die zwei inneren Schichten „reduzierten“ Rinde ist augenscheinlich normal, d. h. nicht von dem ECG der normalen Rinde zu unterscheiden. 2. Eine Analyse der Strychninzacken im ECG in den verschiedenen Stadien der Vergiftung bei lokaler Strychninvergiftung der Rinde wird gegeben. 3. Die AuffassungBergers, das seine α- und β-Wellen des EEG in verschiedenen Schichten zustande kommen, wird auf Grund dieser neuen experimentellen Ergebnisse und aus theoretischen Grunden zuruckgewiesen.
The Holy Spirit as Agent, not Activity: Origen's Argument with Modalism and its Afterlife in Didymus, Eunomius, and Gregory of Nazianzus

In the latter half of the fourth century, Didymus the Blind, Eunomius of Cyzicus, and Gregory of Nazianzus all responded to the position that the Holy Spirit is merely an activity of God, and not a substantial reality. Heretofore, those who held this position have remained unidentified in modern scholarship. In this article, it is argued that the fourth-century arguments derive directly from an authentic fragment (number 37) of Origen’s Commentary on John , in which Origen argues against some form of modalism, perhaps Sabellianism. Origen’s use of John 3:8 together with 1 Corinthians 12:11 became decisive for later theologians in ascribing agency to the Spirit. Despite their obvious differences, Didymus, Eunomius, and Gregory follow Origen in viewing it as imperative to speak of the Spirit as a substantial reality in order to preserve the scriptural portrayal of the Spirit as active. Accordingly, this article provides testimony to the diverse legacy of Origen in the fourth century, as well as to the function of ‘substance’ language in fourth-century doctrinal disputes.
Fe2?Mg2 and TiAl2?MgSi2 exchange reactions between clinopyroxenes and silicate melts

The interdependence of the Fe(Mg)−1 (e.g., FeO-MgO in silicate melt; CaFeSi2O6-CaMgSi2O6 in pyroxene) and TiAl2(MgSi2)−1 exchange reactions between silicate melts and coexisting Ca-pyroxene has been examined. High-calcium clinopyroxenes were grown in 1 atmosphere melting and crystallization experiments on rock powders spanning the composition range tholeiite to melilitite (1,092<T<1,150° C: \(f_{{\text{O}}_{\text{2}} } \)∼QFM). Only microprobe analyses of the crystal rims were used in conjunction with those of the quenched glasses. Assuming equilibrium, relationships between apparent distribution coefficients for Fe2+⇄Mg2+ exchange and \((X_{{\text{Ti}}^{{\text{4 + }}} }^{M1} )^{{\text{CPX}}} \) suggest that at given values of \(\mu _{{\text{Fe(Mg)}}_{ - {\text{1}}} } \) extent of Fe(Mg)−1 substitution is strongly coupled with the TiAl2(MgSi2)−1 substitution in pyroxenes near the five-component space CaMg(Si2O6-CaFe(Si)2O6-CaTi(Al)2O6-CaFe‴(Al,Si)2O6-CaAl(Al,Si)2O6. The inferred stabilization of Ti in iron-rich relative to magnesium pyroxene is consistent with the operation of Fe2+⇄Ti4+ intervalence charge transfer interactions (e.g., Rossman 1980) and observations on zoning in natural titanaugites (e.g., Tracy and Robinson 1977). Although the rims of some pyroxenes grown in some melting experiments exhibit prominent zoning in TiAl2(MgSi2)−1, the average values of \((X_{{\text{Ti}}^{{\text{4 + }}} }^{M1} /X_{{\text{Mg}}^{{\text{2 + }}} }^{M1} )\) inferred from the compositions of these pyroxenes, together with those of the relatively homogeneous pyroxenes produced in crystallization experiments, exhibit a 1∶1 correlation with values of \(\mu _{{\text{TiAl}}_{\text{2}} ({\text{MgSi}}_{\text{2}} )_{ - 1} } \) derived from the solution model of Ghiorso et al. (1983) with a standard error of 750 calories. The Ti contents of Ca-rich pyroxenes crystallizing from a wide range of natural silicate liquids can therefore be predicted.
Preterm premature rupture of membranes.

Although the etiology of preterm premature rupture of membranes (PPROM) is probably multifactorial, recent literature has indicated that infectious processes may play an important role. The management of PPROM is still controversial, requiring individualization of care for each patient. Expectant management is increasingly advocated. The role of adjuvant therapies using antibiotics, ateroids, and tocolytic agents remains to be definitively determined. The following review article addresses recent litera ture involving the PPROM patient.
Semi-automated segmentation of microbes in color images

The goal of this work is to develop a system that can semi-automate the detection of multicolored foreground objects in digitized color images that also contain complex and very noisy backgrounds. Although considered a general problem of color image segmentation, our application is microbiology where various colored stains are used to reveal information on the microbes without cultivation. Instead of providing a simple threshold, the proposed system offers an interactive environment whereby the user chooses multiple sample points to define the range of color pixels comprising the foreground microbes of interest. The system then uses the color and spatial distances of these target points to segment the microbes from the confusing background of pixels whose RGB values lie outside the newly defined range and finally finds each cell's boundary using region-growing and mathematical morphology. Some other image processing methods are also applied to enhance the resultant image containing the colored microbes against a noise-free background. The prototype performs with 98% accuracy on a test set compared to ground truth data. The system described here will have many applications in image processing and analysis where one needs to segment typical pixel regions of similar but non-identical colors.
Dynorphin-phospholipid membrane interactions: role of phospholipid head-group and cholesterol.

The interaction of the κ-opioid receptor-selective heptadecapeptide dynorphin A(1-17) (Tyr1-Gly-Gly-Phe-Leu5-Arg-Arg-Ile-Arg-Pro10-Lys-Leu-Lys-Trp-Asp15-Asn-Glu) with phospholipid membranes has been investigated by monitoring the leakage of the internal aqueous contents of liposomes, the changes in the tryptophan emission spectrum, and the collisional quenching of tryptophan fluorescence by brominated lipids. The peptide induces more extensive leakage of contents from phosphatidylserine than from phosphatidyl-choline vesicles, and experiences a blue shift of the Trp fluorescence emission maximum in the presence of phosphatidylserine vesicles. In the presence of phosphatidylcholine vesicles, however, the Trp fluorescence intensity is reduced without a blue shift. In phosphatidylserine membranes containing 10 mol% phosphatidylcholine, the intensity of the blue-shifted fluorescence is enhanced. This avid interaction of dynorphin A(1-17) with phosphatidylserine membranes is likely to be mediated by the positively charged Arg and Lys groups. It is proposed that. while the N-terminus of the peptide may be embedded in the bilayer in analogy with dynorphin (1–13), the C-terminal region of dynorphin A (1-17) bends back onto the bilayer/water interphase, and that the Trp14, residue is stabilized in a hydrophobic pocked near the interphase by the interaction of the neighboring charged amino acids with the phosphate, carboxyl and amino groups on phosphatidylserine. ©Munksgaard 1996.
Mid-Miocene propagation of the Yellowstone mantle plume head beneath the Columbia River basalt source region

Columbia River flood-basalt volcanism is the product of mid-Miocene distortion of the Yellowstone mantle plume head against the Precambrian margin of North America. The overall migration pattern of Columbia River basalt vents reflects northward propagation of the plume head beneath the west-southwest–migrating North American plate. Thermal uplift mimics the vent migration. Over the 1.5 m.y. of Grande Ronde basalt extrusion, the projected crest of the plume head migrated 105 km (7 cm/yr), from the Chief Joseph dike swarm east-oortheast into the Clearwater embayment, where uplift occurred over the same period at a rate of 0.67 mm/yr. Chemical variations reflect progressive melting of the plume and mantle lithosphere, followed by the mixing of these components with an enriched source from the overriding craton. Rapid thickening of the plume head against the cratonic margin led to decompressional melting and magma rise beneath a thin oceanic lithosphere of accreted terranes.
Six-quark model for the suppression of $delta$S = 1 neutral currents

We propose an alternative arising naturally in a six-quark model to the Glashow--Iliopoulos--Maiani mechanism for the suppression of $delta$S = 1 neutral currents. While violating the Cabibbo form of universality, it maintains the tan$sup 2$ theta/sub C/ suppression of strange particle decays and introduces an additional tan theta/sub C/ suppression of charmed-particle decays. (AIP)