cssi/SciSciGPT-SciSciNet huggingface dataset:
Steroid Biosynthesis by the Equine Testis

Enzyme reactions in the stallion testis involved in steroid synthesis were studied to determine the factors which account for the high production of estrogens as well as androgens. In comparison with other species, the stallion testis was found to have lower 17β- (testosterone) dehydrogenase activity and very high 19-(androstenedione) hydroxylase and aromatizing systems. As a consequence, while androstenedione served as a precursor of both testosterone and estrone, a greater proportion was converted to the estrogen. The 19-hydroxylation and aromatizing activities for testosterone seemed lower than those for androstenedione. The 3β-hydroxysteroid dehydrogenase systems for 17-hydroxypregnenolone and dehydroepiandrosterone were very active, but the A6-17,20- lyase system was apparently much less active than the A4-17,20-lyase. The predominant route of biosynthesis seems, therefore, to be: pregnenolone →17-hydroxypregnenolone →17-hydroxyprogesterone →Δ4-androstenedione →19-hydroxy- ↓androstenedione→estrone te...
Combined computational fluid dynamic and metabolic model of liver defatting under flow

Macrosteatotic livers have become endemic in our nation as obesity continues to rise, consequently leading to a decrease in the number of viable transplantable livers in the donor pool. Considering orthotopic liver transplantation has been proven to be the most effective cure for liver failure caused by macrosteatotic livers, it is imperative a method be developed in order to recondition livers into their lean, fully functioning form for transplant. Prior research groups have shown that metabolic preconditioning is a viable option for liver defatting. Others used computational work to explain the importance of oxygen and an accurate liver geometry. In our laboratory, we have experimentally shown that we can reduce the degree of macrosteatosis in the liver. However this approach is limited because the kinetics of defatting currently exceed the therapeutic window in terms of liver transplantation. We wish to develop a novel computational fluid dynamic model coupled with a kinetic model of hepatocyte metabolism to identify key rate limiting pathways inherent in lipid droplet breakdown and removal within hepatocytes. Currently, our model includes key physiological aspects of the liver such as flow rate, oxygen concentration and distribution, and robust metabolic and cellular-transport models. This model, upon experimental validation, will provide a screening tool to optimize defatting protocols and reagents to develop a clinical protocol which will reduce macrosteatosis in marginal donor organs to allow for pre-conditioning within a therapeutic time-frame.
Building the IT Workforce of the Future: The Demand for More Complex, Abstract, and Strategic Knowledge

The software development process has undergone a considerable amount of change from the early days of spaghetti code to the present state of the art of development using strategic patterns. This has caused not only changes in the toolkits that developers use, but also a change in their mindset-the way that they approach and think about software development. This study uses revealed causal mapping techniques to examine the change in mindset that occurs across the procedural to OO development transition, and lays the foundation for future studies of the OO/ pattern cognitive transition. The results indicate that there is not only increasing complexity in the cognitive maps of the OO developers, but also that there is a need for the developer to shift from routine, assembly line coding to more abstract thought processes.
GM1 ganglioside in the treatment of Parkinson's disease: long-term clinical experience

The monosialoganglioside GM1 is a glycosphingolipid with putative neuroprotective and neurorestorative properties. GM1 has been shown to at least partially reverse neurochemical, neuropathological and behavioral deficits in various lesion models including experimental models of parkinsonism in rodents, felines and nonhuman primates. Based on these experimental findings, we conducted a randomized double blind placebo controlled trial of GM1 in Parkinson's disease (PD). The results of this study showed significant improvements in Unified Parkinson's Disease Rating Scale (UPDRS) motor ratings as well as in other indices of motor function and activities of daily living assessments in PD patients that received 16 weeks of GM1 treatment (Schneider et al. Neurology 1998; 50: 1630–1636). At the conclusion of that study, patients were allowed to receive GM1 in an open extension trial. Fifteen patients chose to receive GM1 and remained in the open trial for approximately 4 years; 11 patients completed the full 5 years open trial. Chronic daily use of GM1 ganglioside by Parkinson's disease patients, over a period of 4–5 years is safe and has led to significant and sustained improvements in motor functioning, in most cases. In addition, we have observed a lower than expected frequency of motor complications of levodopa therapy (i.e. levodopa-induced dyskinesias) in this patient group. Although the precise mechanisms of action of GM1 ganglioside are still unclear, animal and in vitro studies suggest that GM1 may interfere with apoptotic and to a lesser extent, necrotic cell death and stimulate cell survival and perhaps fiber/terminal sprouting through a variety of cellular/molecular processes.
Commentary on ‘Prophylactic antibiotics for preventing pneumococcal infection in children with sickle cell disease’

This is a commentary on a Cochrane review, published in this issue of EBCH, first published as: Hirst C, Owusu-Ofori S. Prophylactic antibiotics for preventing pneumococcal infection in children with sickle cell disease. Cochrane Database of Systematic Reviews 2002, Issue 3. Art. No.: CD003427. DOI: 10.1002/14651858.CD003427. Further information for this Cochrane review is available in this issue of EBCH in the accompanying EBCH Summary and Characteristics and Key Findings Tables articles. Copyright © 2007 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd. The Cochrane Collaboration
Structural characterization of the reaction pathway in phosphoserine phosphatase: crystallographic "snapshots" of intermediate states.

Abstract Phosphoserine phosphatase (PSP) is a member of a large class of enzymes that catalyze phosphoester hydrolysis using a phosphoaspartate–enzyme intermediate. PSP is a likely regulator of the steady-state d -serine level in the brain, which is a critical co-agonist of the N-methyl- d -aspartate type of glutamate receptors. Here, we present high-resolution (1.5–1.9 A) structures of PSP from Methanococcus jannaschii, which define the open state prior to substrate binding, the complex with phosphoserine substrate bound (with a D to N mutation in the active site), and the complex with AlF3, a transition-state analog for the phospho-transfer steps in the reaction. These structures, together with those described for the BeF3− complex (mimicking the phospho-enzyme) and the enzyme with phosphate product in the active site, provide a detailed structural picture of the full reaction cycle. The structure of the apo state indicates partial unfolding of the enzyme to allow substrate binding, with refolding in the presence of substrate to provide specificity. Interdomain and active-site conformational changes are identified. The structure with the transition state analog bound indicates a “tight” intermediate. A striking structure homology, with significant sequence conservation, among PSP, P-type ATPases and response regulators suggests that the knowledge of the PSP reaction mechanism from the structures determined will provide insights into the reaction mechanisms of the other enzymes in this family.
Direct action of thyroxine on skin of the adult newt.

Abstract Thyroxine-cholesterol and cholesterol control pellets were implanted subcutaneously in thyroidectomized, adult newts, Diemictylus viridescens . No molting of the skin was induced by cholesterol control implants or by thyroxine-cholesterol implants containing less than 0.02 μg thyroxine. Localized molting of the skin was induced by 39% of the implants containing approximately 0.02 to 0.96 μg thyroxine. Generalized molting of the skin over the entire surface of the body was induced by 37% of such implants and by all implants containing larger amounts of thyroxine. The occurrence of local molts immediately above and adjacent to thyroxine implants in thyroidectomized newts is attributed to a direct action of thyroxine upon the skin. It is therefore concluded that thyroid hormone probably acts directly upon the skin to cause molting in normal, adult newts.
Two years of growth hormone therapy in young children with Prader–Willi syndrome: Physical and neurodevelopmental benefits

Infants with Prader-Willi syndrome (PWS) typically display failure to thrive and decreased muscle mass with excess body fat for age. Growth hormone (GH) therapy in children with PWS improves, but does not normalize, body composition and muscle strength and agility. The objective of this study was to determine the effects of earlier GH therapy on anthropometric measurements, body composition, and psychomotor development in affected PWS infants and toddlers. Twenty-five subjects, ages 4-37 months, were randomized to 2 years of GH therapy (1 mg/m(2)/day) or 1 year of observation without GH treatment and then placed on GH (1.5 mg/m(2).day) for 1 year only. Anthropometric measurements were obtained by standard methods: percent body fat, lean body mass, and total body bone mineral density by dual x-ray absorptiometry; motor constructs of mobility and stability by the Toddler Infant Motor Evaluation; and cognitive and language function by the Capute Scales of Infant Language and Cognitive Development. GH-treated PWS subjects demonstrated normalization of length/height standard deviation scores (SDS), faster head growth, increased lean body mass accrual, and decreased percent body fat (P < 0.005 for all parameters), as well as improved language (P = 0.05) and cognitive (P = 0.02) quotient Z-scores compared with similarly aged untreated PWS subjects after 1 year into the study. PWS subjects treated before their first birthday spoke their first words at a mean age of 14.4 +/- 2.8 months and walked independently at 23.3 +/- 4.8 months. GH therapy was well-tolerated; however, one PWS subject experienced scoliosis progression. As greater benefits were seen in our study with early treatment, prompt referral to a pediatric endocrinologist for consideration of GH therapy is recommended for PWS at an early age.
Covering grids and orthogonal polygons with periscope guards

Abstract The problem of finding minimum guard covers is NP-hard for simple polygons and open for simple orthogonal polygons. Alternative definitions of visibility have been considered for orthogonal polygons. In this paper we try to determine the complexity of finding guard covers in orthogonal polygons by considering periscope visibility. Under periscope visibility, two points in an orthogonal polygon are visible if there is an orthogonal path with at most one bend that connects them without intersecting the exterior of the polygon. We show that finding minimum periscope guard (as well as k-periscope and s-guard) covers is NP-hard for 3-d grids. We present an O(n3) algorithm for finding minimum periscope guard covers for simple grids and discuss how to extend the algorithm to obtain minimum k-periscope guard covers. We show that this algorithm can be applied to obtain minimum periscope guard covers for a class of simple orthogonal polygon in O(n3).
Numerous mesothelial cells in tuberculous pleural effusions.

Tuberculous pleural effusions are characterized by the absence or paucity of mesothelial cells. Two cases of pleural tuberculosis are reported in which significant numbers of mesothelial cells were found. (Cheat 1989; 96:438–39)
Development and Characterization of CdZnTe Detectors for Neutrino Physics Research

Abstract CdZnTe crystals contain 9 double beta decay isotopes and can serve simultaneously as source and detector in a search for neutrino-less double beta decay. In particular, 116Cd and 130Te are suitable isotopes in such a search due to their high Q-values. The endpoint of the beta spectra resulting from double-beta decay of these isotopes is well above natural gamma lines which constitute backgrounds to a potential signal. Detectors for neutrino-less double beta decay searches require good energy resolution and effective background rejection. Both properties can be realized with position sensitive pixilated detectors that have particle tracking capabilities. CdZnTe detectors are promising detectors to satisfy these criteria and have the additional advantage of room temperature operation. We are developing and characterizing the performance of co-planar and pixilated CdZnTe detectors, study their charged particle tracking capabilities and evaluate their use in future neutrino-less double beta decay search experiments. Results from our laboratory measurements will be presented.
Anti-platelet agents augment cisplatin nanoparticle cytotoxicity by enhancing tumor vasculature permeability and drug delivery

Tumor vasculature is critically dependent on platelet mediated hemostasis and disruption of the same can augment delivery of nano-formulation based chemotherapeutic agents which depend on enhanced permeability and retention for tumor penetration. Here, we evaluated the role of Clopidogrel, a well-known inhibitor of platelet aggregation, in potentiating the tumor cytotoxicity of cisplatin nano-formulation in a murine breast cancer model. In vivo studies in murine syngeneic 4T1 breast cancer model showed a significant greater penetration of macromolecular fluorescent nanoparticles after clopidogrel pretreatment. Compared to self-assembling cisplatin nanoparticles (SACNs), combination therapy with clopidogrel and SACN was associated with a 4 fold greater delivery of cisplatin to tumor tissue and a greater reduction in tumor growth as well as higher survival rate. Clopidogrel enhances therapeutic efficiency of novel cisplatin based nano-formulations agents by increasing tumor drug delivery and can be used as a potential targeting agent for novel nano-formulation based chemotherapeutics.
Shatterbelts and conflict behaviour: The effect of globalisation on ‘high risk’ states

This article ties together seemingly disparate literatures (those of globalisation and ‘shatterbelt states') as a means of investigating the changing conflict behaviour of high‐risk states. The objective of this research is to ascertain empirically whether the circumstances that generate aggression by high‐risk states are the same as those for others. In addition, by examining how conflict behaviour has changed over time, and in conjunction with trade openness, these tests speak to the importance of economic interdependence as a mitigating counterforce to aggressive tendencies. The results indicate that domestic instability and fragmentation are more directly tied to high‐risk state behaviour than are systemic influences. In contrast, the probability that low‐risk states originate or participate in conflicts, and resort to violence, is tied to international factors. Surprisingly, increased repression seems to result from the opposite circumstances. For high‐risk states, changes in repressive behaviour are...
Analysis of cushion systems for impact protection design of bridges against overheight vehicle collision

Abstract Based on several theoretical models of elastic and elastic–plastic impact as well as energy method, a systematic methodology for design analysis of cushion structures for impact protection of bridges against overheight vehicle collision is presented with consideration of the shear-off effect of projectiles and the nonlinear crushing behavior of sandwich cores. Three design criteria based on contact force, deflection, and energy are proposed, and the theoretical models for elastic, elastic–plastic, and after-densification impact including the shear-off effect of projectile are developed to improve the analysis and design of cushion structures against overheight vehicle impact. Realistic analysis of cushion structures is resulted from the above models, and it can be applied to design of cushion structures for the sake of bridge protection from overheight vehicle collision.
Physical and Sensory Attributes of a trans-Free Spread Formulated with a Blend Containing a Structured Lipid, Palm Mid-Fraction, and Cottonseed Oil

Physical and sensory attributes of an experimental trans-free margarine spread (MG-X) and two commercial margarine spreads (MG-A and MG-B) were studied. The trans-free margarine spread was formulated with a blend containing a structured lipid (SL) synthesized by reacting canola oil with 40% stearic acid (w/w), palm mid-fraction (PMF), and cottonseed oil (CTO). No trans fatty acids were detected in MG-X, whereas the trans fatty acid contents of MG-A and MG-B were 0.3 and 3.7% (w/w), respectively. MG-X was considerably firmer than MG-A and MG-B, less cohesive, and its adhesiveness was intermediate between those of MG-A and MG-B. MG-X’s stability to syneresis was also intermediate between those of MG-A and MG-B. Sensory evaluation showed that MG-X was comparable to MG-A in terms of spreadability and texture only, but was significantly different from MG-B in all attributes.
The art in dermatitis.

A 32-year-old healthy Somali-American woman presented with one week of a pruritic papular rash over the dorsum of both hands. The rash appeared 7 days after her first henna application. There were no other new skin products identified. She was diagnosed with henna-induced allergic contact dermatitis and treated with a high potency topical corticosteroid and antihistamines with resolution of the lesions. Henna is a plant native to Africa and southern Asia and is commonly used to dye skin and hair. Pure henna as a dyeing agent rarely causes skin sensitization. However, paraphenylenediamine (PPD) is often added to henna to speed drying and darken the dye. The addition of PPD to henna tattoo mixtures is increasingly being recognized as a cause of allergic contact dermatitis. Treatment consists of topical corticosteroids with or without antihistamines. In severe cases, systemic corticosteroids may be warranted. Post-inflammatory hyperpigmentation may occur following the resolution of the dermatitis.
Ex vivo human placental transfer and the vasoactive properties of hydralazine.

Abstract Objective: The purpose of this study was to determine the placental transfer and fetal vascular effects of hydralazine in an ex vivo human placental system. Study Design: Nine placentas from uncomplicated term vaginal or cesarean deliveries were studied by means of the ex vivo single-cotyledon perfusion system. Antipyrine was used for the reference compound in the determination of the clearance index of hydralazine. Fetal vascular effects of hydralazine were determined by the effects on the perfusion pressure of the fetal artery in a constant-flow open system. Variations in fetal pressure were analyzed with the 1-sample Student t test. Results: The clearance index of hydralazine ranged from 0.61 ± 0.18 to 0.73 ± 0.14. The accumulation of hydralazine in the recirculated fetal compartment was linear in relationship to the maternal concentration. Fetal pressure changes were noted in 6 of the 9 placentas, or 66.6%. The mean change in pressure was –4.1 ± 4.4 mm Hg ( P = .0231). Conclusions: Hydralazine readily crosses the ex vivo human placental perfusion system. (Am J Obstet Gynecol 2000;182:167-9.)
Crack tip stress fields under complex loads: Application to pressure vessel problems

Abstract An experimental method which combines the equations of linear elastic fracture mechanics with the frozen stress photoelastic method in order to estimate stress intensity factors in three dimensional mixed mode cracked body problems is briefly described. Its use is illustrated by applying the method to a part circular flaw under mixed mode loads and to the well known nozzle corner crack problem. Finally, limitations and extensions of the method are discussed.
Using SWIG to bind C++ to Python

An increasingly popular approach to scientific computing is to combine Python and compiled modules. Such an approach merges the high performance typically found in compiled routines with the interface of a flexible, scalable, and easy-to-learn interpreted language. Although using C to hand-code extensions to Python binds the latter to a given compiled asset in C++, programmers who used C++'s more advanced features (until recently) lacked the automated support available in Fortran and C. One tool for creating Python bindings to C the Simplified Wrapper and Interface Generator. SWIG-an open-source application used by a large and ever-expanding community-began as an effort to expose physics packages in a large parallel simulation code to interpreted languages. SWIG preprocesses C and C++ code and generates library bindings in several interpreted languages including Python, Pert, Tcl, and Java. Recent improvements to SWIG provide greater support for binding C++ code. SWIG now creates, for example, bindings for some of C++'s more advanced features such as templates and exceptions. This article explores how SWIG does this by examining a series of small C++ code examples.
A Probabilistic Contour Observer for Online Visual Tracking

This paper presents an online, recursive filtering strategy for contour-based tracking. Approaching the tracking problem from an estimation perspective leads to an observer design for the visual track signal associated with an individual target in an image sequence. The track state of the observer is decomposed into group and shape components that describe the gross location and the nonrigid shape, respectively, of the object. A probabilistic representation describes the shape nonparametrically. The constitutive components of the observer are detailed, which include a dynamical prediction model and a correction mechanism. Incorporating the probabilistic observer into the tracking process leads to improved performance and segmentations. The improvements are validated through application of the observer to recorded imagery with evaluation via objective measures of quality.
Concentrations of Dissolved and Particulate Polychlorinated Biphenyls in Water from the Saginaw River, Michigan

The Saginaw River receives water from a major drainage basin in the east-central portion of the lower peninsula of Michigan. Historically the river has been contaminated with polychlorinated biphenyls (PCBs) from several sources. The present study was conducted to determine the concentrations of PCBs in both the dissolved and particulate phases of water in the lower Saginaw River, as well as the relative contribution of PCBs from the lower portion of the river relative to more upstream locations. Water samples were collected in 1990–1991, during a range of discharge conditions. Suspended particulates were collected from water onto glass-fiber filters by use of a “Penta-plate” filtration apparatus. Filtered water was subsequently passed through XAD-2 macroreticular resin to collect the “dissolved” PCBs. Concentrations of PCBs in both phases were determined by congener specific gas chromatography with electron capture detection. Total concentrations of PCBs ranged from 11 to 31 ng/L. The concentrations of PCBs in the dissolved phase ranged from 1.9 to 16 ng/L. The ratio of total PCBs bound to suspended particulates, relative to dissolved PCBs, was 2:1 and remained fairly constant for discharges less than approximately 400 M3/sec. The loading of total PCBs to Saginaw Bay was estimated to be 225 kg/yr, of which approximately 60% was found to be contributed by the lower 8 km of the Saginaw River.
Health Effects of Common Home, Lawn, and Garden Pesticides

Children encounter pesticide products and their residues where they live and play and in the food supply. Pesticide exposure affects pediatric health both acutely and chronically; effects range from mild and subtle to severe. Pediatricians play an important role in identifying and reducing significant pesticide exposure in their patients by taking an exposure history to clarify the extent and types of exposures that may have occurred during acute care and preventive care visits. Developing knowledge about the toxicity of various chemicals, identifying reliable resources for pesticide information, and providing a common-sense approach toward recommending the safest practical alternatives is necessary.
Pulmonary manifestations of disseminated cryptococcosis in patients with AIDS.

Forty-eight patients with disseminated cryptococcosis and AIDS were retrospectively studied to define the pulmonary manifestations. Cryptococcus neoformans (CN) was first isolated from a pulmonary site in 12 patients. Disseminated disease was subsequently documented in all these patients. Symptoms and roentgenographic manifestations (normal, nodular/circumscribed infiltrates, pleural effusions, lobar consolidation) were diverse. Interstitial infiltrates predicted the presence of another opportunistic lung infection besides cryptococcosis in five patients (three untreated and two treated patients). Infectious causes other than cryptococcosis were established by culture and clinical course in five of the ten patients who developed chest roentgenographic abnormalities during amphotericin B therapy. Endobronchial abnormalities were identified in four patients at bronchoscopy. Bronchoalveolar lavage (9/9) and pleural fluid (3/3) cultures were sensitive tests for detection of pulmonary involvement with CN. (Chest 1990; 98:1060–66)
LATTICE CHIRALITY AND ITS USES AT LARGE Nc

A brief overview of the authors' work on lattice chirality and its application to the numerical study of planar QCD is presented.
Spin Waves and Nuclear Magnetic Resonance Enhancement in Ni F 2 Domain Walls

We have obtained the allowed magnetic resonance modes or spin waves in the canted antiferromagnet Ni${\mathrm{F}}_{2}$ in the presence of a Bloch wall. Our formulation includes the anisotropy and exchange energies of the crystal together with characteristics of the wall such as its stiffness, mass, and viscosity. From the dispersion equations, we show that there exists a bound wall excitation branch having a lower excitation energy than the free spin wave excitation branch. Further, we have calculated the effective nuclear magnetic resonance field enhancement due to the bound wall excitation branch as a function of the parameters of the crystal and the Bloch wall and shown that our results are equivalent to those obtained experimentally. Finally, we compare this enhancement with that of a pure antiferromagnet---demonstrating that the canting is essential for this process.
Concepts: x-ray telescopes with high-angular resolution and high throughput

The high rate at which importatn results are emanating formthe Chandra X-ray Observatory heightens our appreciation of the significance of high angular resolution telescopes in x-ray astronomy. However, the Chandra telescope is probably the last member of a line of high resolution telescopes with a conventional architecture. Qualitative improvement upon Chandra's resolution requires a new technology. We discuss a promising approach that is capable potentially of achieving microarcsecond resolution, possibly the highest angular resolution in astronomy of any wavelength band. It is based upon x-ray optics that focus by transmission at normal incidence rather than by reflection at grazing incidence. Its components are refractive lenses and Fresnel zone plantes. Extreme chromatic aberration is intrinsic to these devices but it can be overcome in small wavelength intervals above 2 keV with a technique described by Van Speybroech and by other methods. Like x-ray interferometry these systems have extremely long focal lengths and require 'formation flying' consisting of precise positioning between the optics and detector that be aboard separate spacecraft spaced far apart. However, it is less demanding of accuracy in formation flying than x-ray interferometery. These systems have much lower mass than grazing incidence telescopes with comparable collecting area.
Non-Resonant and Resonant Chaotic Dynamics in Externally Excited Cyclic Systems

The present work studies the vibratory response of geometrically nonlinear cyclic structures to harmonic excitations. These cyclic structure, in their linear approximations, possesses pairwise double degenerate natural frequencies with orthogonal normal modes. The dynamic response of such systems, when excited near primary resonance, is studied using the method of averaging. The averaged equations, representing the evolution of the amplitudes and phases of the interacting normal modes, are known to exhibit complex dynamics including period-doupling bifurcations and Silnikov type chaos. The higher-dimensional Melnikov method and its extensions by Kovacic and Wiggins, and Haller and Wiggings, to dissipative and nondissipative singular systems are utilized to detect the transversal intersection of stable and unstable manifolds of periodic orbits. Such intersections imply the existence of Smale horseshoes and, hence, chaotic dynamics for the averaged system.
Anisotropy in the structure of pressure-induced disordered solids.

Molecular dynamics calculations revealed that a pressure-induced ``amorphized'' solid is disordered and anisotropic but not structurally related to an isotropic quenched melt. The results explain the anomalous elastic behavior observed via Brillouin scattering on \ensuremath{\alpha}-quartz [L. E. McNeil and M. Grimsditch, Phys. Rev. Lett. 68, 83 (1991)]. The reversal in frequency shifts for sound propagation in the perpendicular and parallel directions is due to the unequal densification in the a and c directions. The helical chains are found to recover upon depressurizing. Anisotropy of pressure amorphized solids is thus a general property, and pressure-induced amorphization is not related to melting.
Initialization for the method of conditioning in Bayesian belief networks

Abstract The method of conditioning allows us to use Pearl's probabilistic-inference algorithm in multiply connected belief networks by instantiating a subset of the nodes in the network, the loop cutset. To use the method of conditioning, we must calculate the joint prior probabilities of the nodes of the loop cutset. We present a method that lets us compute these joint priors by instantiating the loop-cutset nodes sequentially.
Regulation of Sialic Acid 9-O-Acetylation during the Growth and Differentiation of Murine Erythroleukemia Cells

Sialic acids are typically found at the terminal position on vertebrate oligosaccharides. They are sometimes modified by an O-acetyl ester at the 9-position, potentially altering recognition of sialic acid by antibodies, lectins, and viruses. 9-O-Acetylation is known to be selectively expressed on gangliosides in melanoma cells and on N-linked chains in hepatocytes. Using a recently developed probe, we show here that in murine erythroleukemia cells, this modification is selectively expressed on another class of oligosaccharides, O-linked chains carried on cell surface sialomucins. These cells also express 9-O-acetylation on the ganglioside GD3, but this modification appears to be undetectable on the cell surface. Increasing cell density in culture is associated with a decrease in cell surface 9-O-acetylation of sialomucins. This change correlates with the spontaneous differentiation toward a mature erythroid phenotype. This down-regulation upon differentiation and entry into the G0/G1 stage of the cell cycle is confirmed by differentiation-inducing agents. In contrast, cells arrested in G2/M by the microtubule depolymerizing agent nocodazole show increased expression of cell surface 9-O-acetylated sialomucins (but not the 9-O-acetylated ganglioside). However, the microtubule stabilizer taxol does not induce this increase, showing that the nocodazole effect is independent of cell cycle stage. Indeed, direct analysis showed no correlation of 9-O-acetylation with cell cycle stage in rapidly growing cells, and shorter treatments with nocodazole also increased expression. Western blots of cell extracts confirmed that changes caused by differentiation and nocodazole are not due to redistribution of molecules from the cell surface. Indeed, following selective removal of 9-O-acetyl groups from the cell surface by a specific esterase, the recovery of expression is mediated by new synthesis rather than by redistribution from an internal pool. Thus, 9-O-acetylation on these sialomucins appears to be primarily regulated by the rate of synthesis, and the increase with nocodazole treatment is likely due to the inhibition of turnover of cell surface molecules. These data show that 9-O-acetylation of sialic acids in murine erythroleukemia cells is a highly regulated modification, being selectively expressed in a cell type-specific manner on certain classes of oligosaccharides and differentially regulated with regard to subcellular localization and to the state of cellular differentiation.
Estrogen elicits dorsal root ganglion axon sprouting via a renin-angiotensin system.

Many painful conditions occur more frequently in women, and estrogen is a predisposing factor. Estrogen may contribute to some pain syndromes by enhancing axon outgrowth by sensory dorsal root ganglion (DRG) neurons. The objective of the present study was to define mechanisms by which estrogen elicits axon sprouting. The estrogen receptor-α agonist propyl pyrazole triol induced neurite outgrowth from cultured neonatal DRG neurons, whereas the estrogen receptor-β agonist diarylpropionitrile was ineffective. 17β-Estradiol (E2) elicited sprouting from peripherin-positive unmyelinated neurons, but not larger NF200-positive myelinated neurons. Microarray analysis showed that E2 up-regulates angiotensin II (ANGII) receptor type 2 (AT2) mRNA in vitro, and studies in adult rats confirmed increased DRG mRNA and protein in vivo. AT2 plays a central role in E2-induced axon sprouting because AT2 blockade by PD123,319 eliminated estrogen-mediated sprouting in vitro. We assessed whether AT2 may be responding to locally...
Towards the elimination of Monte Carlo statistical fluctuation from dose volume histograms for radiotherapy treatment planning.

The Monte Carlo calculation of dose for radiotherapy treatment planning purposes introduces unavoidable statistical noise into the prediction of dose in a given volume element (voxel). When the doses in these voxels are summed to produce dose volume histograms (DVHs), this noise translates into a broadening of differential DVHs and correspondingly flatter DVHs. A brute force approach would entail calculating dose for long periods of time - enough to ensure that the DVHs had converged. In this paper we introduce an approach for deconvolving the statistical noise from DVHs, thereby obtaining estimates for converged DVHs obtained about 100 times faster than the brute force approach described above. There are two important implications of this work: (a) decisions based upon DVHs may be made much more economically using the new approach and (b) inverse treatment planning or optimization methods may employ Monte Carlo dose calculations at all stages of the iterative procedure since the prohibitive cost of Monte Carlo calculations at the intermediate calculation steps can be practically eliminated.
Targeting Organic Anion Transporter 3 with Probenecid as a Novel Anti-Influenza A Virus Strategy

Influenza A virus infection is a major global health concern causing significant mortality, morbidity, and economic loss. Antiviral chemotherapeutics that target influenza A virus are available; however, rapid emergence of drug-resistant strains has been reported. Consequently, there is a burgeoning need to identify novel anti-influenza A drugs, particularly those that target host gene products required for virus replication, to reduce the likelihood of drug resistance. In this study, a small interfering RNA (siRNA) screen was performed to identify host druggable gene targets for anti-influenza A virus therapy. The host organic anion transporter-3 gene (OAT3), a member of the SLC22 family of transporters, was validated as being required to support influenza A virus replication. Probenecid, a prototypical uricosuric agent and chemical inhibitor of organic anion transporters known to target OAT3, was shown to be effective in limiting influenza A virus infection in vitro (50% inhibitory concentration [IC(50)] of 5.0 × 10(-5) to 5.0 × 10(-4) μM; P < 0.005) and in vivo (P < 0.05). Probenecid is widely used for treatment of gout and related hyperuricemic disorders, has been extensively studied for pharmacokinetics and safety, and represents an excellent candidate for drug repositioning as a novel anti-influenza A chemotherapeutic.
Immune modulation in Pompe disease treated with enzyme replacement therapy.

Pompe disease is a lysosomal storage disease characterized by massive glycogen deposition in skeletal, cardiac and smooth muscle secondary to the deficiency of acid α-glucosidase (GAA) [1]. Once ra...
Katalytische Untersuchungen an Legierungen. XVII. Der Zerfall des Ameisensäuredampfes an pulverförmigen und kompakten Nickel–Eisen‐Mischkatalysatoren

Nach der statischen Methode wurde die Zersetzung von Ameisensauredampf an pulverformigen und kompakten Nickel- und Nickel–Eisen-Katalysatoren untersucht. Die Reaktionsordnung wurde bestimmt, die Aktivitaten gemessen und die Aktivierungsenergien berechnet. Die pulverformigen Katalysatoren zeigten bei 60% Nickel ein Aktivitatsmaximum. Die Messungen an kompakten Legierungen bewiesen, das das Aktivitatsmaximum bei den Pulvern durch die Vergroserung der Oberflache verursacht wurde. Bei den kompakten Katalysatoren blieb die Wirksamkeit des Nickels auch in den Legierungen mit Eisen annahernd erhalten, nur das reine Eisen war erheblich inaktiver. Dies ist sehr wahrscheinlich durch den Ubergang vom kubisch-flachenzentrierten zum kubisch-raumzentrierten Gitter verursacht. Durch Walzen wurde die Aktivierungsenergie der Reaktion an den kompakten Katalysatoren erhoht, dabei stieg die Aktivitat des Nickels, die des Eisens sank etwas. Mogliche Ursachen werden diskutiert. Die spezifische Aktivitat der Pulver unterschied sich nur wenig von der der kompakten Katalysatoren. The decomposition of formic acid was studied on NiFe-catalysts in the form of powders and of sheets. The dimension of the surface and the type of crystal lattice influenced the catalytic efficiency. The reaction on rolled sheets had a higher activation energy.
Analysis of the relationship between MODIS aerosol optical depth and PM2.5 in the summertime US

MODIS aerosol optical depth (AOD) product provides a quantitative measure of columnar aerosol abundance over both land and ocean. The satellite-derived AOD has shown to correlate with surfaced-measured PM2.5 (particulate matter particulate matter with aerodynamic diameter < 2.5 μm) concentration. The timely MODIS AOD product from direct broadcasting facilitates near real-time (1-2 hours after satellite overpass) monitoring of PM distribution and movement over the continental US the Infusing Satellite into Environmental Application (IDEA) (http://idea.ssec.wisc.edu). Many questions, however, are raised in regard to correlation between AOD and PM2.5. In this paper, we characterize the correlation between MODIS AOD and surface-measured PM2.5 in different conditions and introduce mean absolute error as a second measure to help assess satellite derived AOD for air quality application.
Endotoxin-activated microglia injure brain derived endothelial cells via NF-κB, JAK-STAT and JNK stress kinase pathways

We previously showed that microglia damage blood brain barrier (BBB) components following ischemic brain insults, but the underlying mechanism(s) is/are not well known. Recent work has established the contribution of toll-like receptor 4 (TLR4) activation to several brain pathologies including ischemia, neurodegeneration and sepsis. The present study established the requirement of microglia for lipopolysaccharide (LPS) mediated endothelial cell death, and explored pathways involved in this toxicity. LPS is a classic TLR4 agonist, and is used here to model aspects of brain conditions where TLR4 stimulation occurs. In monocultures, LPS induced death in microglia, but not brain derived endothelial cells (EC). However, LPS increased EC death when cocultured with microglia. LPS led to nitric oxide (NO) and inducible NO synthase (iNOS) induction in microglia, but not in EC. Inhibiting microglial activation by blocking iNOS and other generators of NO or blocking reactive oxygen species (ROS) also prevented injury in these cocultures. To assess the signaling pathway(s) involved, inhibitors of several downstream TLR-4 activated pathways were studied. Inhibitors of NF-κB, JAK-STAT and JNK/SAPK decreased microglial activation and prevented cell death, although the effect of blocking JNK/SAPK was rather modest. Inhibitors of PI3K, ERK, and p38 MAPK had no effect. We show that LPS-activated microglia promote BBB disruption through injury to endothelial cells, and the specific blockade of JAK-STAT, NF-κB may prove to be especially useful anti-inflammatory strategies to confer cerebrovascular protection.
Cloning, Characterization, and Chromosomal Mapping of a Phospholipase (Lecithinase) Produced by Vibrio cholerae

Phospholipases are associated with virulence in bacterial diseases. Vibrio cholerae produces a phospholipase (lecithinase), with enzyme production visualized as a zone of clearing around colonies plated on egg yolk agar. The role of phospholipase in gut colonization or disease pathogenesis is unknown. We used the egg yolk agar assay to clone and characterize a gene encoding a phospholipase from V. cholerae El Tor strain E7946. Sequence analysis revealed a 1,254-bp open reading frame (lec) encoding a 418-amino-acid protein with a predicted molecular weight of 47,600. The predicted sequence exhibits DNA homology to other Vibrionaceae phospholipases. A potential signal sequence exists in the predicted amino acid sequence, as does a lipid binding motif found in prokaryotic and eukaryotic phospholipases and lipases. Polyacrylamide gel electrophoresis combined with an egg yolk agarose overlay demonstrated phospholipase activity migrating at a relative molecular weight of 45,000 in preparations of V. cholerae and the Escherichia coli clone. Restriction mapping and Southern blot analysis revealed that lec, hlyA (hemolysin), and hlyC (lipase) are adjacent on the V. cholerae chromosome, and chromosomal digests of several El Tor, classical, and O139 (Bengal) strains demonstrated conservation of this gene arrangement. An in-frame internal deletion of the lec gene was constructed and recombined into the chromosome of attenuated V. cholerae El Tor strain CVD 110. The resulting mutant lacked lecithinase activity on egg yolk agar but had undiminished reactivity in rabbit ligated ileal loop assays.
Uniprocessor performance enhancement through adaptive clock frequency control

Uniprocessor designs have always assumed worst-case operating conditions to set the operating clock frequency and, hence, performance. However, much more performance can be obtained under typical operating conditions through experimentation, but such increased frequency operation is subject to the possibility of system failure and, hence, data loss/corruption. Further, mobile CPUs such as those in cell phones/Internet browsers do not adapt to their current surroundings (varying temperature conditions, etc.) so as to increase or decrease operating frequency to maximize performance and/or allow operation under extreme conditions. We present a digital hardware design technique realizing adaptive clock-frequency performance-enhancing digital hardware; the technique can be tuned to approximate performance maximization. The cost is low and the design is straightforward. Experiments are presented evaluating such a design in a pipelined uniprocessor realized in a field programmable gate array (FPGA).
Mobility reconfiguration for terrain exploration using passive perception

The ability of robotic units to autonomously navigate various terrains is critical to the advancement of robotic operation in natural environments. Next generation robots will need to adapt to their environment in order to accomplish tasks that are either too hazardous, too time consuming, or physically impossible for human-beings. Such tasks may include accurate and rapid explorations of various planets or potentially dangerous areas on Earth. Furthermore, because terrain variability typically increases as the distance that a rover traverses increases, it will be beneficial for robotic units to adapt to their surroundings. As a result, this research investigates a navigation control methodology for a multi-modal locomotive robot based upon passive perception. Surface estimation for robot reconfigurability is implemented using a region growing method, which characterizes the traversability of the terrain, in conjunction with passive perception regarding motion. A mathematical approach is then implemented that inherits human psychological aspects to direct necessary navigation behavior to control robot mobility. Physical experimentations in a simulated Mars yard are presented to validate the methodology.
Phase space acceptance of LMF transport schemes

Three different ion beam transport schemes (achromatic lens, wire-guided transport, and Z-discharge channel) for the light ion beam driver for the Laboratory Microfusion Facility (LMF) are examined analytically. For each case the phase space acceptance area is investigated, including the effects of angular momentum. It is shown that, in real diode/transport configurations, there will be some angular momentum (i.e. phi /sub 0/ not=0) created, e.g. by combinations of diode microdivergence, beam steering errors, foil scattering, and gas scattering. Both the ballistic/lens case and the channel case can accept phi /sub 0/=0 beams if they can be made, and can also tolerate certain amounts of phi /sub 0/ not=0. On the other hand, the wire case requires phi /sub 0/ not=0 in a carefully prepared manner. It is concluded that, in regard to angular momentum, the baseline ballistic case is the most accepting transport scheme. The channel transport scheme is less accepting. The wire transport scheme is the least accepting because it requires a tailored nonzero phi /sub 0/ distribution to be fully accepted. >