cssi/SciSciGPT-SciSciNet huggingface dataset:
Fetal glucose metabolism and oxygen consumption during sustained hypoglycemia.

The present study was conducted to determine the effects of chronic maternal hyperinsulinemia and hypoglycemia on fetal glucose metabolism and fetal growth. Umbilical glucose uptake (UGU), fetal glucose use rate (GUR), and oxidation fraction (GOxF), and fetal endogenous glucose production rate (EGPR) were measured in chronically catheterized, late gestation fetal lambs during moderate (group 2, n = 6) or marked (group 3, n = 6) maternal hypoglycemia induced by chronic maternal insulin infusion. Compared with normoglycemic controls (group 1, n = 10), group 2 moderate hypoglycemic animals had a 38.5% reduction in maternal glucose concentration (GA) with a subsequent 40.3% fall in fetal glucose concentration (Ga), 64% decrease in fetal insulin concentration (Ia), and a 28.9% decrease in UGU. Group 2 fetal GUR fell 13.1%. No significant EGPR was found in group 1 animals; group 2 had a measurable EGPR that was not statistically different from zero due to the wide range of values. In group 3 marked hypoglycemic animals GA was 57.4% lower than control, and Ga, Ia, and UGU were reduced 45.9%, 64%, and 75.7%, respectively. However, GUR fell by only 19.6% due to the appearance of significant fetal EGPR of 2.81 +/- 0.32 mg/min/kg. Fetal GUR in both group 2 and 3 animals were higher than the predicted range (mean +/- 1 SEM) compared with our model of fetal GUR response to changes in glucose and insulin concentrations. Fetal weights at autopsy were lower in groups 2 and 3 than group 1 controls at the same gestational age (P less than .05). We conclude that decreased fetal glucose availability leads to fetal hypoglycemia and hypoinsulinemia, development of fetal endogenous glucose production, and fetal growth retardation.
An embedding for the big bang

A cosmological model is given that has good physical properties for the early and late universe but is a hypersurface in a flat five-dimensional manifold. The big bang can therefore be regarded as an effect of a choice of coordinates in a truncated higher-dimensional geometry. Thus the big bang is in some sense a geometrical illusion.
Multiculturalism, Teaching Slavery, and White Supremacy

This article argues that multiculturalism, especially when it is led and controlled by Whites, and in the absence of collective anti-racist struggles, can reproduce the ontologies, epistemologies, and practices of white supremacy. I use a case study of a reenactment of Atlantic black slavery, produced by white teachers to investigate whether multiculturalism can be more than a technology of white supremacy. I conclude that by employing the restored behaviors of slavery, the reenactment failed to add to an interrogation of whiteness and anti-racism. Instead of contributing to the reformation of whiteness and the empowering of Blacks, it reinforced anti-blackness. I end with a discussion of how to teach slavery ethically.
Genetic factors in end-stage renal disease

Genetic factors in end-stage renal disease. Despite more aggressive treatment of diabetes, hypertension, and hyperlipidemia, the incidence and prevalence rates of end-stage renal disease (ESRD) continue to increase worldwide. The likelihood of developing chronic kidney disease in an individual is determined by interactions between genes and the environment. Familial clustering of nephropathy has repeatedly been observed in all population groups studied and for multiple etiologies of kidney disease. A three- to nine-fold greater risk of ESRD is observed in individuals with a family history of ESRD. Marked racial variation in the familial aggregation of kidney disease exists, with high rates in African American, Native American, and Hispanic American families. Disparate etiologies of nephropathy aggregate within African American families, as well. These data have led several investigators to search for genes linked to diabetic and other forms of nephropathy. Evidence for linkage to kidney disease has been detected and replicated at several loci on chromosomes 3q (types 1 and 2 diabetic nephropathy), 10q (diabetic and nondiabetic kidney disease), and 18q (type 2 diabetic nephropathy). Multicenter consortia are currently recruiting large numbers of multiplex diabetic families with index cases having nephropathy for linkage and association analyses. In addition, large-scale screening studies are underway, with the goals of better defining the overall prevalence of chronic kidney disease, as well as educating the population about risk factors for nephropathy, including family history. Given the overwhelming burden of kidney disease worldwide, it is imperative that we develop a clearer understanding of the pathogenesis of nephropathy so that individuals at risk can be identified and treated at earlier, potentially reversible, stages of their illness.
Acrylonitrile irreversibly inactivates glyceraldehyde-3-phosphate dehydrogenase by alkylating the catalytically active cysteine 149.

Abstract Acrylonitrile (AN) is a vinyl monomer used in the production of synthetic fibers, rubber and plastics. AN is acutely toxic but its mechanism of toxicity remains to be established. AN is metabolized to cyanide in vivo but cyanide production alone cannot explain acute AN toxicity. Previous work in our laboratory has shown that AN can alkylate highly reactive cysteine residues in proteins. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a critical enzyme involved in glycolysis, has a catalytically active cysteine 149 in its active site. We report that AN irreversibly inhibits GAPDH with second-order rate constants, at pH 7.4, of 3.7 and 9.2 M−1 s−1 at 25 and 37 °C, respectively. A combination of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF) and electrospray ionization–mass spectrometry–mass spectrometry (ESI–MS–MS) was used to show that AN inactivates GAPDH by covalently binding to cysteine 149 in the active site of the enzyme. Inactivation of GAPDH by AN would be expected to impair glycolytic ATP production and when coupled with the inhibition of mitochondrial ATP synthesis by the AN metabolite cyanide would result in metabolic arrest. The brain can withstand metabolic arrest for only a few minutes thus these combined actions may account for the acute toxicity of AN in vivo.
Properties of in vivo nitrogenase activity in Beggiatoa alba

A procedure was devised for analyzing in vivo nitrogenase activity in Beggiatoa alba B18LD which involves: (1) the induction of nitrogenase in cells pre-grown on NH4Cl, by washing the cells free of NH4Cl and lowering their exposure to oxygen, and (2) measuring acetylene reduction by these cells. Using this induction methodology we examined the effects of pH, temperature, and nitrogenous compounds on in vivo nitrogenase induction and activity in Beggiatoa alba B18LD. Nitrate and nitrite repressed the induction of nitrogenase activity, but glutamine did not. Induction and activity had a combined pH optimum of 6.5 to 8.0, and activity had a temperature optimum of 29°C. Ammonium and urea caused immediate inhibition of nitrogenase activity, but nitrate, nitrite, glutamine, asparagine, and other amino acids did not. Ammonium-induced inhibition was transient and incomplete, and the duration of inhibition increased in direct proportion to the amount of ammonium added. Methionine sulfoximine, a glutamine synthetase inhibitor, at a final concentration of 50 μM blocked ammonium uptake by cells, but did not prevent nitrogenase inhibition if added before ammonium. Our results imply that B. alba nitrogenase inhibition by ammonium: (1) is not directly caused by ammonium assimilation products, (2) is probably not due to an enzymatic inactivation, and (3) may be related to ammonium transport.
Exploring the structure and redox activity of hexacoordinate bis(bipyridyl)silicon(IV) complexes

Abstract A series of hexacoordinate bis(bipyridyl)silicon(IV) complexes was synthesized by allowing [Si(bpy)2I2]I2 to react with the alcohols or phenols: methanol, ethylene glycol, phenol, 2,2′-biphenol, or 1,2-benzendiol. Crystal structures were obtained for the corresponding complexes: [Si(bpy)2(OMe)2] (I)(I3) (1), [Si(bpy)2(-OCH2CH2O-)]I2 (2), [Si(bpy)2(OPh)2](I3)2 (3), [Si(bpy)2(bph)](PF6)2 (4), and [Si(bpy)2(cat)](PF6)2 (5), (bpy = 2,2′-bipyridine, cat = 1,2-benzenediolato, bph = 2,2′-biphenolato ligand). All five complexes exist as distorted octahedral dications with readily exchangeable counterions. The hexafluorophosphate salts of each complex cation exhibit a reversible, first reduction wave around −1 V (versus Fc+/Fc) in acetonitrile, nearly independent of the alkoxide or diolate substituent. This is consistent with DFT calculations indicating a LUMO localized on the bipyridyl ligands. The complexes with bidentate diolate ligands possess multiple reversible reduction waves.
Lysophosphatidylcholine Modulates Cardiac INa via Multiple Protein Kinase Pathways

Lysophosphatidylcholine (LPC) is a naturally occurring intracellular phospholipid metabolite that has been implicated in arrhythmogenesis during ischemia. LPC has been shown to affect the cardiac Na+ current (I(Na)), but the mechanism of modulation remains undescribed. Recently, low concentrations of LPC have been shown to activate protein kinase C (PKC) independent of the receptor-delineated pathway. The purposes of this study were to describe the effects of intracellularly introduced LPC on I(Na) and to determine if these effects were mediated by kinases. Modulation of I(Na) was studied in ventricular cells with LPC (1 nmol/L to 1 micromol/L) internally applied using whole-cell patch-clamp techniques. Intracellular LPC caused a dose-dependent depolarizing shift of steady state inactivation that was accompanied by a change in slope factor. The development of resting inactivation from closed states was delayed 40%, whereas the recovery from inactivation was significantly accelerated. These results were mimicked by another bioactive lipid, lysophosphatidylethanolamine, or by a peptide analogue of PKC, which is a potent stimulator of endogenous PKC activity. Maximal recruitable current was significantly increased by LPC but not by PKC activation. Some of the effects of LPC on I(Na) could be partially inhibited by the specific PKC inhibitor chelerythrine chloride or by downregulation of PKC with phorbol ester pretreatment. However, genistein, a specific tyrosine kinase inhibitor, completely inhibited all the modulation of I(Na) caused by LPC. These data suggest that LPC modulates I(Na) in cardiac myocytes by a pathway that involves both PKC-dependent and tyrosine kinase- dependent phosphorylation.
The embryonic development of the equine heart.

Equine cardiogenesis was studied in embryos of approximately 21 to 49 days of gestation, with particular attention to the partitioning of the ventricular outflow channel. Timing of several morphogenetic events associated with this partitioning was recorded in Table 1. Present investigation indicated that partitioning of the ventricular outflow channel into the pulmonary trunk and aorta was already completed at about 36th to 38th day of gestation. Results of this study may aid in better understanding of the congenital malformations, especially those associated with great vessels of the equine heart.
Valuing mineral reserves when capacity constrains production

Abstract We add a capacity constraint and heterogeneous reserves to the Hotelling Valuation Principle. This produces a more general version of the principle that is more consistent with empirical valuations, while retaining the underlying relationship between net price and reserve value.
Many-electron aspects of molecular promotion in ion-atom collisions - Production of core-excited states of Li in Li/+/-He collisions

Production of core-excited autoionizing states of neutral Li having configurations of the form 1snln(prime)l(prime) has been observed over the impact-energy range from 10-50 keV. Although the results for production of all such states is remarkably consistent with a quasi-molecular-excitation model proposed by Stolterfoht and Leithaeuser (1976), production of individual lines in the observed spectra exhibits collision-velocity dependencies indicative of considerably more complex processes, including processes which appear to be inherently two-electron in nature. Excitation functions are presented for (1s2s/2/)/2/S, 1s(2s2p/3/P)/2/P, 1s(2s2p/1/P)/2/P, and (1s2p/2/)/2/D core-excited state of Li and for total core excitation.
Acoustic trauma increases cochlear and hair cell uptake of gentamicin.

Background Exposure to intense sound or high doses of aminoglycoside antibiotics can increase hearing thresholds, induce cochlear dysfunction, disrupt hair cell morphology and promote hair cell death, leading to permanent hearing loss. When the two insults are combined, synergistic ototoxicity occurs, exacerbating cochlear vulnerability to sound exposure. The underlying mechanism of this synergism remains unknown. In this study, we tested the hypothesis that sound exposure enhances the intra-cochlear trafficking of aminoglycosides, such as gentamicin, leading to increased hair cell uptake of aminoglycosides and subsequent ototoxicity.
Medium-chain oil reduces fat mass and down-regulates expression of adipogenic genes in rats.

Objective: To test the hypothesis that adipose tissue could be one of the primary targets through which medium-chain fatty acids (MCFAs) exert their metabolic influence. Research Methods and Procedures: Sprague-Dawley rats were fed a control high-fat diet compared with an isocaloric diet rich in medium-chain triglycerides (MCTs). We determined the effects of MCTs on body fat mass, plasma leptin and lipid levels, acyl chain composition of adipose triglycerides and phospholipids, adipose tissue lipoprotein lipase activity, and the expression of key adipogenic genes. Tissue triglyceride content was measured in heart and gastrocnemius muscle, and whole body insulin sensitivity and glucose tolerance were also measured. The effects of MCFAs on lipoprotein lipase activity and adipogenic gene expression were also assessed in vitro using cultured adipose tissue explants or 3T3-L1 adipocytes. Results: MCT-fed animals had smaller fat pads, and they contained a considerable amount of MCFAs in both triglycerides and phospholipids. A number of key adipogenic genes were down-regulated, including peroxisome proliferator activated receptor γ and CCAAT/enhancer binding protein α and their downstream metabolic target genes. We also found reduced adipose tissue lipoprotein lipase activity and improved insulin sensitivity and glucose tolerance in MCT-fed animals. Analogous effects of MCFAs on adipogenic genes were found in cultured rat adipose tissue explants and 3T3-L1 adipocytes. Discussion: These results suggest that direct inhibitory effects of MCFAs on adiposity may play an important role in the regulation of body fat development.
Total synthesis of aphidicolin

Abstract A total synthesis of the antiviral antitumor diterpenoid, aphidicolin (1), is reported. The synthesis starts from the known Δ4-4,10-dimethyioctalin-3,9-dione (5) and requires 15 steps. The two key steps are the Claisen rearrangement of cyclopentenol vinyl ether 16 to unsaturated aldehyde 17, and the carbonylation of unsaturated tosylate 20 to ketone 21. The Claisen rearrangement gives largely cyclopentadiene elimination product under most conditions. We found, however, that thermolysis in the presence of potassium t-pentoxide gives the desired Claisen product 17 in 60% yield. The second key step is carbonylation of 20 with Collman's reagent, disodium tetracarbonylferrate. This reaction, which has not previously been used in natural products synthesis, takes place in 30% yield, and finishes the construction of the aphidicolin skeleton. (±) Aphidicolin was identical with an authentic sample by IR, 1H and 13CNMR, and GC/MS.
Microwave and far-infrared propagation in conductive microstructured composites

Abstract In a recent publication [T.E. Huber, L. Luo, Appl. Phys. Lett. 70 (1997) 2502.] we discussed a structural enhancement of the electromagnetic transmission in composites. We showed that densely packed arrays (76% volume fraction) of 10 μm diameter parallel indium wires exhibit an enhanced transmission, of ∼ 10 3 , relative to an indium foil of equal thickness for far-infrared (10 cm −1 k cm −1 ) propagating along the wire length. The absorption increases as k 0.45 ± 0.07 and is explained by the dynamic Maxwell-Gannett model, which includes eddy current dissipation. It is of considerable practical interest to extend the range of application of these composite properties to the microwave domain. Here we will discuss recent measurements of the transmission of microwaves in wire array composites in the 8–12 GHz frequency range.
Differential distribution of the glutamate transporters GLT-1 and GLAST in tanycytes of the third ventricle.

The ventral one-third of the ventricular lining in the hypothalamus is formed by specialized ependymal cells called the tanycytes. These cells may serve a neuroendocrine transport function because of their structural specializations, which include apical microvili on the ventricular surface and long basal processes that terminate on blood vessels or on the glia limitans. Here, we describe the expression of mRNA and protein for the glutamate transporters GLT-1 and GLAST in unique tanycyte populations of the third ventricle in rat brain. Using nonisotopic in situ hybridization, we demonstrate GLAST mRNA labeling in tanycytes of the ventral floor and lateral walls in the tuberal and mammillary recess portions of the third ventricle. This GLAST mRNA labeling had a higher intensity than the labeling intensity observed in regular ependymal cells throughout the ventricular system. Furthermore, we have identified strong GLT-1 mRNA labeling in a population of tanycytes situated in the dorsolateral walls of caudal tuberal and mammillary recess portions. Immunocytochemical staining indicates that both GLT-1 and GLAST protein are expressed in the tanycyte populations as well. These data corroborate previous findings that third ventricle tanycytes are functionally heterogeneous. Furthermore, the GLT-1-expressing tanycytes represent a population of tanycytes that, to date, has not been recognized as functionally distinct. The strong GLAST expression by the ventral tanycytes in the hypophysiotropic area suggests a role of tanycyte-mediated glutamate transport in neuroendocrine activity. The functional role of GLT-1 in dorsal wall tanycytes remains to be explored.
Fungi associated with biological soil crusts in desert grasslands of Utah and Wyoming

Biological soil crusts of arid and semiarid regions of the world are recognized as one of the least explored niches occupied by fungi. The principal species of fungi associated with biocrusts in de...
Characterization of Epstein-Barr virus-specific T-cell hybridomas derived from infectious mononucleosis

Somatic cell hybridization was utilized to produce hybrids with surface receptors that would pertain directly to those expressed in vivo during Epstein-Barr virus (EBV) infection. Lymphocytes were obtained during acute infectious mononucleosis (IM) and fused to a double mutant of the JM human T-lymphoma cell lines. Hybrid cells that reacted with autologous EBV-infected lymphoblasts were detected by the release of Interleukin-2 into the culture medium. Reactive hybridomas also released IL-2 following coculture with allogeneic EBV-infected cells when those cells shared HLA-DR antigens of the primary parental cells. In contrast, stimulator cells with no shared HLA-DR or without evidence of EBV infection never induced IL-2 release. These results suggest the existence of a population of T cells that arise during acute IM and could account for the known proliferative phase of the disease. The requirements of IL-2 stimulation are currently under study using this system.
Distancing in encompassing education settings: Lessons from Jewish education

Abstract Irving Sigel's distancing theory and his cognitive and educational research has led to an understanding of the importance of “encompassing” educational settings and the promotion of positive developmental outcomes in the area of Jewish education. This paper describes how distancing theory provides a basis for understanding the effects of identity-enhancing educational settings. An examination of parallels between challenges confronted by Jewish educators and by educators in secular American settings broadens the applications of Dr. Sigel's work. The authors draw from their work with Jewish education to make recommendations for secular American education.
Models for Compressible Elasto-Plasticity Based on Internal State Variables

A general constitutive framework is presented for rate-independent porous plasticity. This framework is formulated using combined nonlinear isotropic-kinematic hardening rules along with void growth models which can be either implicitly embedded within a pressure dependent yield function or explicitly established based on a micromechanical model. A void nucleation criterion is also introduced in the framework. An associative flow rule is first set forth which implicitly introduces general void growth models. Correlations are presented with experimentally determined porosity evolution in circumferentially notched specimens subjected to various superimposed hydrostatic pressures. The framework is then generalized to include explicit void growth models with plastic flow which are either associative or non-associative with the yield function. Single element computations are carried out using these model frameworks to compare the behavior predicted by specific implicit and explicit void growth models.
Eigenvalues of the Laguerre Process as Non-Colliding Squared Bessel Processes

Let $A(t)$ be an $n\times p$ matrix with independent standard complex Brownian entries and set $M(t)=A(t)^*A(t)$. This is a process version of the Laguerre ensemble and as such we shall refer to it as the Laguerre process . The purpose of this note is to remark that, assuming $n > p$, the eigenvalues of $M(t)$ evolve like $p$ independent squared Bessel processes of dimension $2(n-p+1)$, conditioned (in the sense of Doob) never to collide. More precisely, the function $h(x)=\prod_{i 0}$ is the Wishart process considered by Bru (1991). There it is shown that the eigenvalues of $M(t)$ evolve according to a certain diffusion process, the generator of which is given explicitly. An interpretation in terms of non-colliding processes does not seem to be possible in this case. We also identify a class of processes (including Brownian motion, squared Bessel processes and generalised Ornstein-Uhlenbeck processes) which are all amenable to the same $h$-transform, and compute the corresponding transition densities and upper tail asymptotics for the first collision time.
Modulation of Retroviral Restriction and Proteasome Inhibitor-Resistant Turnover by Changes in the TRIM5α B-Box 2 Domain

An intact B-box 2 domain is essential for the antiretroviral activity of TRIM5α. We modeled the structure of the B-box 2 domain of TRIM5α based on the existing three-dimensional structure of the B-box 2 domain of human TRIM29. Using this model, we altered the residues predicted to be exposed on the surface of this globular structure. Most of the alanine substitutions in these residues exerted little effect on the antiretroviral activity of human TRIM5α hu or rhesus monkey TRIM5α rh . However, alteration of arginine 119 of TRIM5α hu or the corresponding arginine 121 of TRIM5α rh diminished the abilities of the proteins to restrict retroviral infection without affecting trimerization or recognition of the viral capsid. The abilities of these functionally defective TRIM5α proteins to accelerate the uncoating of the targeted retroviral capsid were abolished. Removal of the positively charged side chain from B-box 2 arginines 119/120/121 resulted in diminished proteasome-independent turnover of TRIM5α and the related restriction factor TRIMCyp. However, testing of an array of mutants revealed that the rapid turnover and retroviral restriction functions of this B-box 2 region are separable.
Data inversion using nonlinear programming with physical constraints: Aerosol size distribution measurement by impactors

Abstract A critical comparison is made of different methods for processing data from impactors, among other measuring instruments, in an effort to improve upon conventional data-processing assuming ideal instrument response. Particle size distribution measurements are simulated numerically and processed, attempting to reproduce known input test distributions. After giving selected examples where promising alternative schemes produce unsatisfactory results, a method which employs nonlinear programming with physically sound constraints is proposed and found to be the most satisfactory of the methods tested.
The response of meiofauna to sediment disturbance

Abstract The meiobenthos inhabiting an intertidal mud bar were disturbed by hand-turning the sediment of a 9-m2 area with a shovel and monitoring the subsequent recolonization process. The immediate impact of the disturbance on this community dominated by Nematoda (91%), Copepoda (4%) and Foraminifera (4%), was to remove more than 70% of the meiofauna. However, after only one tidal cycle, total numbers of nematodes, copepods, foraminiferans and other meiofauna taxa were at predisturbance and control (similar 9-m2 site on the same flat) density values. Nematode species assemblages rapidly adapted to the disturbance and changed little over time. Foraminifera showed insignificant fluidized flocculent upper layer of sediment was probably the major dispersal mechanism in this community, and foraminiferans seem to be the least able to use this mechanism. The meiobenthos of this habitat is described as a well-dispersed and dynamic community able to rapidly adjust to small-scale disturbances. However, the meiobenthos may not recover from all disturbances, because resilience was only determined for a limited physical disturbance.
Conceptual Framework of Coalitions in an Organizational Context

Summary Organizations are forming coalitions in their struggle to survive with fewer resources. Under the “Contract With America,” funds for human services are expected to be increasingly cut back. Organizational actors will continue to coalesce because of their compelling interests to serve disadvantaged populations in our communities. This article uses the political-economy perspective in presenting a conceptual framework of coalitions in organizational settings. We need access to various perspectives and models of coalition building in order to provide direction for organizational groups as they attempt to change the sociopolitical structures in which they must operate.
Disc Electrophoresis of Turkey Serum Alkaline Phosphatase Isoenzymes Using Polyacrylamide Gel 1. Procedure

The isoenzymes of alkaline phosphatase in turkey serum were separated by disc electrophoresis using polyacrylamide gel as the supporting medium In this laboratory we have been unable to adapt polyacrylamide gel electrophoresis procedures for turkey serum that had been described by previous workers as successful in separating the isoenzymes of avian alkaline phosphatase. A rapid and repeatable procedure that yielded excellent resolution of alkaline phosphatase isoenzymes was devised. This procedure involved a step-by-step determination of the following: a suitable gel system, buffer system, staining procedure and sample preparation.
A small subunit processome protein promotes cancer by altering translation

Dysregulation of ribosome biogenesis or translation can promote cancer, but the underlying mechanisms remain unclear. UTP18 is a component of the small subunit processome, a nucleolar multi-protein complex whose only known function is to cleave pre-ribosomal RNA to yield the 18S ribosomal RNA component of 40S ribosomal subunits. Here, we show that UTP18 also alters translation to promote stress resistance and growth, and that UTP18 is frequently gained and overexpressed in cancer. We observed that UTP18 localizes to the cytoplasm in a subset of cells, and that serum withdrawal increases cytoplasmic UTP18 localization. Cytoplasmic UTP18 associates with the translation complex and Hsp90 to upregulate the translation of IRES-containing transcripts such as HIF1a, Myc and VEGF, thereby inducing stress resistance. Hsp90 inhibition decreases cytoplasmic UTP18 and UTP18-induced increases in translation. Importantly, elevated UTP18 expression correlates with increased aggressiveness and decreased survival in numerous cancers. Enforced UTP18 overexpression promotes transformation and tumorigenesis, whereas UTP18 knockdown inhibits these processes. This stress adaptation mechanism is thus co-opted for growth by cancers, and its inhibition may represent a promising new therapeutic target.
Wake Collapse in a Stratified Fluid: Linear Treatment

The linear initial-value problem of a partially mixed cylindrical wake in a, uniformly stratified fluid is formulated and exact solutions are given for the density and velocity fields inside and just outside the original cylinder. An asymptotic expression for the far-field internal wave radiation is given and the corresponding solutions for a spherical wake geometry are noted. The treatment emphasizes the inadequancy of the usual linear Boussinesq approximation to describe the detailed nature of similar problems, in particular the fully mixed wake-collapse problem.
Thermodynamic properties of enzyme-catalyzed reactions involving cytosine, uracil, thymine, and their nucleosides and nucleotides

The standard Gibbs energies of formation of species in the cytidine triphosphate series, uridine triphosphate series, and thymidine triphosphate series have been calculated on the basis of the convention that Delta(f)G=0 for the neutral form of cytidine in aqueous solution at 298.15 K at zero ionic strength. This makes it possible to calculate apparent equilibrium constants for a number of reactions for which apparent equilibrium constants have not been measured or cannot be measured because they are too large. This paper adds fifteen reactants to the database BasicBiochemData3 at MathSource that includes 199 reactants. The standard transformed Gibbs energies of formation of these fifteen reactants are used to calculate apparent equilibrium constants at 298.15 K, ionic strength 0.25 M, and pHs 5, 6, 7, 8, and 9 for thirty two reactions. The pKs, standard Gibbs energies of hydrolysis, and standard Gibbs energies of deamination are given for these fifteen reactants.
Oxidative stress and endothelial activation

The vascular endothelial surface is a major target of oxidative stress, but we are only now beginning to understand the molecular sources and physiologic consequences of such oxidative activity. Along with exogenous oxidants, provided by professional phagocytes or circulating enzymes, vascular cells generate oxidants in response to cytokine and growth factor stimulation, and these endogenous oxidants participate in vascular cell signal transduction. Endothelial cells express at least four of the five principal subunits of an NADPH oxidase, and we review evidence that such an oxidase is tightly regulated in both activity and in subcellular targeting. Both of these features are likely to contribute to the signal specificity of unstable oxidants.
Botox therapy for ischemic digits.

Background:Treating patients with Raynaud's phenomenon who have chronic pain and ulcerations is extremely challenging. Unrelenting pain can lead to dysfunction and disuse, rendering the patient debilitated and/or chronically depressed. Pharmacologic vasodilators and surgical sympathectomies offer va
Sarcomere lattice geometry influences cooperative myosin binding in muscle.

In muscle, force emerges from myosin binding with actin (forming a cross-bridge). This actomyosin binding depends upon myofilament geometry, kinetics of thin-filament Ca2+ activation, and kinetics of cross-bridge cycling. Binding occurs within a compliant network of protein filaments where there is mechanical coupling between myosins along the thick-filament backbone and between actin monomers along the thin filament. Such mechanical coupling precludes using ordinary differential equation models when examining the effects of lattice geometry, kinetics, or compliance on force production. This study uses two stochastically driven, spatially explicit models to predict levels of cross-bridge binding, force, thin-filament Ca2+ activation, and ATP utilization. One model incorporates the 2-to-1 ratio of thin to thick filaments of vertebrate striated muscle (multi-filament model), while the other comprises only one thick and one thin filament (two-filament model). Simulations comparing these models show that the multi-filament predictions of force, fractional cross-bridge binding, and cross-bridge turnover are more consistent with published experimental values. Furthermore, the values predicted by the multi-filament model are greater than those values predicted by the two-filament model. These increases are larger than the relative increase of potential inter-filament interactions in the multi-filament model versus the two-filament model. This amplification of coordinated cross-bridge binding and cycling indicates a mechanism of cooperativity that depends on sarcomere lattice geometry, specifically the ratio and arrangement of myofilaments.
Nucleosome disruption precedes transcription and is largely limited to the transcribed domain of globin genes in murine erythroleukemia cells.

Abstract We used micrococcal nuclease to separate murine erythroleukemia cell (MELC) chromatin into soluble and insoluble fractions which differ in gene content and chromatin structure. Genes that are not expressed in the erythroid lineage, such as the Igα and albumin genes. distribute preferentially into the soluble rather than the insoluble fraction, and are organized into nucleosomes in both fractions. Both α 1 - and β maj -globin genes are enriched in the insoluble fraction and are organized into structures that are partially devoid of nucleosomes in uninduced MELC, when the genes are transcriptionally inactive. Following chemical induction of MELC and the onset of globin gene transcription, globin gene enrichment and nucleosome disruption in the insoluble chromatin fraction increase. Using seven DNA subclones that span the β maj -globin gene we show that insolubility and nucleosome disruption are largely limited to DNA sequences lying within the transcribed domain. Non-transcribed, flanking sequences are soluble and organized into nucleosomes. In addition, the globin genes found in insoluble, non-nucleosomal chromatin contain previously engaged RNA polymerases which can elongate globin RNA chains in vitro in a pattern qualitatively and quantitatively similar to intact nuclei. These results are discussed in terms of a model for globin gene activation during erythropoeisis.
Case study: Systematic desensitization of homosexuality

Research has indicated that fears of women and of heterosexual intercourse are usual components of male homosexuality. It is suggested that homosexual behavior can therefore be conceptualized as a substitute form of sexual gratification, motivated by a fear of heterosexuality. This formulation indicates that aversive conditioning is an inappropriate treatment for homosexuality, as it does not eliminate the fear which motivates homosexual behavior. Systematic desensitization of fear of women is proposed as the appropriate treatment of male homosexuality. A case report which illustrates the successful treatment of homosexuality by systematic desensitization is presented. The use of a “third person,” both as a treatment aide and a source of data, is discussed. Moral issues in the treatment of homosexuality are reviewed briefly. It is suggested that behavior therapists consider motivation and etiology as well as overt behavior in choosing a treatment technique for a particular case.
Müller cell and neuronal remodeling in retinal detachment and reattachment and their potential consequences for visual recovery: a review and reconsideration of recent data

Recent evidence suggests that the adult mammalian retina is far more plastic than was previously thought. Retinal detachment induces changes beyond the degeneration of outer segments (OS). Changes in photoreceptor synapses, second- and even third-order neurons may all contribute to imperfect visual recovery that can occur after successful reattachment. Changes that occur in Muller cells have obvious effects through subretinal fibrosis and proliferative vitreoretinopathy, but other unidentified effects seem likely as well. Reattachment of the retina induces its own set of responses aside from OS re-growth. Reattachment halts the growth of Muller cell processes into the subretinal space, but induces their growth on the vitreal surface. It also induces the outgrowth of rod axons into the inner retina.
Hsp90 Inhibitor Can Inhibit UV Carcinogenesis

Extensive exposure to solar UVR is a well-recognized etiologic factor for cutaneous non-melanoma skin cancer. In this issue of the Journal, Singh et al. show that topical treatment of the skin with 17-[allylamino]-17-demethoxygeldanamycin (17AAG), a heat-shock protein 90 (Hsp90) inhibitor, prevents UVR-induced squamous cell carcinomas (SCCs) in mice. The inhibitory effect of 17AAG on SCC was associated with the inhibition of the UVR-induced (i) hyperplastic response, (ii) Hsp90β-PKCe interaction, and (iii) pStat3 and pAkt expression in mouse skin.
Supraoptic neurons in the rat hypothalamo-neurohypophysial explant: Double-labeling with lucifer yellow of injection and immunocytochemical identification of vasopressin- and neurophysin-containing neuroendocrine cells

By combining intracellular electrophysiology with double-labeled intracellular dye-marking and immunocytochemical identification of the same magnocellular neuroendocrine cell, we studied supraoptic neurons in the rat hypothalamo-neurohypophysial explant in vitro. This report examines neurophysiological and light microscopical features of vasopressin- and neurophysin-immunoreactive, pituitary-projecting supraoptic neurons.
A Conceptual Model of Factors Contributing to the Development of Muscle Dysmorphia

Muscle dysmorphia is a recently described subcategory of Body Dysmorphic Disorder. It is most prevalent in males and has a number of cognitive, behavioral, socioenviornmental, emotional, and psychological factors that influence its expression. An etiological model describing these influences is presented for evaluation. Nine variables (body mass, media influences, ideal body internalization, low self-esteem, body dissatisfaction, health locus of control, negative affect, perfectionism, and body distortion) were identified through the use of extant literature on muscle dysmorphia and through extrapolation from literature involving women and eating disorders. The functional relationships among these variables are described and implications of the model are discussed.
AFM characterization of dendrimer-stabilized platinum nanoparticles.

This work describes the use of atomic force microscopy (AFM) to measure the size of dendrimer-stabilized Pt nanoparticles (Pt DNs) deposited from aqueous solutions onto mica surfaces. Despite considerable previous work in this area, we do not fully understand the mechanisms by which PAMAM dendrimers template the formation of Pt DNs. In particular, Pt DN sizes measured by high-resolution transmission electron microscopy (HRTEM) are reported to be larger than expected if one assumes that each PAMAM molecule templates one spherical Pt nanoparticle. AFM provides a vertical height measurement that complements the lateral dimension measurement from HRTEM. We show that AFM height measurements can distinguish between “empty” PAMAM and Pt DNs. If the complexation of Pt precursor with PAMAM is prematurely terminated, AFM images and feature height distributions show evidence of arrested precipitation of Pt colloids. In contrast, sufficient Pt−PAMAM complexation time leads to AFM images and height distributions that ...
Predation on zooplankton by the benthic anthozoans Alcyonium siderium (Alcyonacea) and Metridium senile (Actiniaria) in the New England subtidal

The Alcyonacean octocoral Alcyonium siderium Verrill and the sea anemone Metridium senile (L.), the only common perennial zooplanktivores on shallow (≦16-m depth) subtidal rock walls in much of northern New England, USA, are of similar heights and overlap in their habitat and microhabit distributions. The coelenteron contents of both species were sampled at four-hour intervals over a diel cycle and were compared to zooplankton available in the water at 1 to 5 cm from the rock wall, the height at which the cnidarians held their feeding tentacles. Prey in coelenterons of A. siderium were significantly smaller (means of 256 to 345 μm), and those in coelenterons of M. senile were equal to or slightly greater in length (means of 415 to 1006 μm) than the available zooplankton. The diets of A. siderium and M. senile differed significantly from each other and from the available zooplankton. A. siderium showed strong positive electivites for ascidian larvae and for foraminiferans, and strongly negative electivities for most crustaceans. M. senile had strong positive electivities for barnacle cyprids, ascidian larvae, and gammarid amphipods, and strong negative electivities for invertebrate eggs, foraminiferans, calanoid and harpacticoid copepods, and ostracods. Electivities may reflect tentacle avoidance or escape by motile prey as well as predator preference. Substratum-associated organisms (e.g. demersal crustaceans, larvae of benthic invertebrates) were the most common items in the diets of both species, suggesting a tight benthic food web, similar to the situation for coral reef anthrozoans which rely on reef-generated zooplankton. A. siderium ate large numbers of ascidian larvae which, as benthic adults, compete for space with A. siderium and can overgrow small colonies. Predation on the larvae of a competing species may alleviate competition by decreasing the competitor's recruitment.
Photosynthetic activity of MSMA-resistant and -susceptible common cocklebur

Abstract MSMA-resistant (R) and -susceptible (S) biotypes of common cocklebur (Xanthium strumarium L.) were used to study PSI and PSII activities, and chlorophyll and carotenoid content of MSMA-treated and -untreated R and S biotypes. MSMA at 1, 10, and 100 mg/L did not inhibit either PSI or PSII activities. The R biotype had higher PSI and PSII activity than the S biotype with and without MSMA treatments. R biotype leaf discs had higher chlorophyll and carotenoid content than the S biotype after treatment with MSMA; the S biotype cotyldeons had higher levels of both pigments as compared to the R biotype cotyledons. MSMA induced a reduction in both pigments in S biotype cotyledons, and in young and mature leaf discs. Results indicate that photosynthetic capability might indirectly be involved in the resistance mechanism and carotenoids may protect against MSMA toxicity, possibly caused by an induced free radical mechanism.
On the disparity gradient limit for binocular fusion

Recently, Burt and Julesz (1980) have measured the limits of single versus double vision (diplopia) in binocular stereopsis. They found that the extent of the fusional limits is not fixed spatially and argued that a limit on the disparity gradient, rather than the absolute disparity magnitude usually associated with the notion of Panum' s fusional area, is the critical factor when two or more objects occur near each other in the (cyclopean) visual field. Their main result was that fusion was never observed when the disparity gradient (defined as the ratio of disparity difference and angular separation as shown in Figure 1) exceeded a critical value of approximately 1. They concluded that this invariant limit captures the role of object interaction in binocular fusion. Despite some criticism (Krol, 1982; Krol & van de Grind, 1980), the concept of limiting disparity gradient would seem to have a rather secure basis in a geometrical analysis of the binocular viewing situation (Kass, 1984; Terzopoulos, 1984) and is currently being used as a major theoretical construct in at least one computational approach to binocular stereomatching (Pollard, Mayhew, & Frisby, 1984). We have found, however, that fusion and single vision can be achieved in situations in which the disparity gradient exceeds, by a factor of 2 to 3, the critical value reported by Burt and Ju1esz(1980). As a demonstration, compare the displays in Figure 2. In general, our experiments revealed that when the context consisted of dots of the same contrast polarity, the limiting disparity gradient (0.96±0.2) was close to the previously reported values. When one of the interacting dots was larger than the other (by a factor of 2) the gradient was elevated to 1.4±0.23 (see also Braddick, 1979). When the interacting dots had opposite contrast polarity and one of the dots was larger than the other, the critical value increased to 2.1 ± 0.3; that is, the gradient below which single vision was experienced increased and larger disparity differences could be tolerated for a given object separation.i Rather than questioning the concept of limiting disparity gradient, our results may be suggesting that the notion of a purely geometrically defined gradient is not satisfactory. Object properties other than mutual separation seem to participate in the interaction context. Burt and
ATM to the desktop

Over the last 2 to 3 years, ATM has emerged as the strategic technology for the WAN and the LAN environments. This paper will explore ATM's capabilities in the LAN and in particular as a desktop connectivity technology. Because of its bandwidth scalability, ATM can accommodate the various bandwidth needs of desktop client and server platforms from 25 to 155 to 622 Mbps. New and emerging desktop applications like videoconferencing, network- based education, and multimedia applications require the isochronous capabilites of ATM. This paper will focus on application requirements on the desktop and how ATM meets those requirements, along with migration strategies from legacy ALNs to ATM. Costs and timing for desktop migration to ATM are discussed.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Kinetics of propane pyrolysis

A kinetic model based on the most important free radical reaction steps has been developed for propane pyrolysis. The kinetic and product distribution data were obtained over a wide range of conversions at temperatures from 700 to 850°C. and with various amounts of steam or other diluents. The results of the investigation clarify the important reaction steps and the effect of the critical operating variables.
A new nonparametric measure of conditional independence

In this paper we propose a new measure of conditional independence that is loosely based on measuring the L 2 distance between the conditional joint and the product of the conditional marginal density functions. However, we propose to smooth the arguments prior to measuring the distance and use kernel density estimation to derive the estimator. We show that under suitable conditions the proposed smoothing does not affect the conditional independence but using proper smoothing function helps in choosing the bandwidth parameter robustly. We discuss the computational issues and propose an approximation to evaluate the estimator efficiently. We apply the proposed measure in different experiments to show its validity.