cssi/SciSciGPT-SciSciNet huggingface dataset:
Toxicity of the Mitochondrial Poison Dequalinium Chloride in a Murine Model System

Dequalinium chloride (DECA), a cationic, lipophilic mitochondrial poison, selectively targets the mitochondrial membrane of certain epithelial carcinoma cells, in which it inhibits cellular energy production. It has demonstrated potency as a cytotoxic agent specific for carcinomas and may provide a novel approach for cancer therapy, either as a single agent or as an adjunct to conventional chemotherapy. The purpose of this study was to determine the toxicity of DECA in the murine model. One hundred female BALB/c mice were divided into three schedule groups. Group one received a single intraperitoneal (ip) dose of DECA at 10, 15, 20, or 25 mg/kg of body weight. Group two received DECA at 6, 7, 8, 9, or 10 mg/kg ip every other day (QOD), and group three received DECA at 10, 11, 12, 13, or 14 mg/kg ip every 7 days. Over a 30- to 60-day period, acute and subchronic toxicities were evaluated on the basis of the following clinical parameters: respiratory distress, weight loss, and mortality. After a single ip administration, we found a maximum tolerated dose of 15 mg/kg and a lethal dose (LD50) of 18.3 mg/kg. Single ip doses of 20 and 25 mg/kg produced > 50% mortality. Histologic examination of the tissues revealed significant damage to the liver and kidneys, with pulmonary congestion occurring secondary to renal-hepatic failure. A cumulative assessment revealed that 60% of the animals tolerated 15 doses of 6 and 7 mg/kg QOD and that 100% tolerated 5 doses of 11 and 12 mg/kg (every 7 days). Higher DECA doses under either regimen induced severe toxic effects and mortality.(ABSTRACT TRUNCATED AT 250 WORDS)
Single cell transcriptome-based dissection of lineage fate decisions in myelopoiesis

In spite of tremendous advances in the analysis of hematopoietic progenitors and transcription factors that give rise to different lineages, molecular insight into the mechanisms that underlie cell fate choice at the level of individual cells is lacking. We utilized single-cell RNA sequencing of murine granulocyte-monocyte progenitors (GMPs) to analyze the molecular basis of cell fate choice. Over 200 libraries were generated with average read depths of 4 million per library and an expressed gene call of over 3,800 genes with FPKM O3. Our data reveal a varied but coherent spectrum of gene expression patterns in individual murine GMPs. The majority of cells could be clustered into ones expressing either granulocytic or monocytic genes, suggesting that they were primed for lineage determination. A minority of GMPs expressed a mixed-lineage pattern of genes. The single-cell data suggested an antagonistic transcription factor circuit involving Gfi1 and IRF8 that was validated with both lossand gain-of-function experiments in GMPs. Our data highlight the utility of single cell RNA-Seq analysis to reveal molecular mechanisms controlling lineage fate decisions in hematopoiesis.
On the Existence in Solution of Doubly Thiolate-Bridged Double Cubanes Containing the Heterometal [MFe3S4] Core (M = Mo, W)

Clusters of the general type {[MFe3S4(SR)2(cat)]2(μ2-SR)2}4- (cat = catecholate) have previously been shown to contain two heterometal cubane-type cores [MFe3S4]3+ (M = Mo, W) linked by two Fe−S(R)−M bridges such that the cluster has idealized centrosymmetry. These clusters resemble the P-clusters of nitrogenase in that both have two μ2-SR bridges between cubane (or cuboidal) halves of the cluster. When dissolved in a strongly coordinating solvent or treated with a suitable ligand L1-,0, the bridges are cleaved to afford the single cubanes [MFe3S4(SR)3(cat)L/(solv)]2-,3-. Because of their relation to P-clusters, the stability and electron transfer properties of the double cubanes have been examined in solution. 1H NMR spectroscopic and cyclic voltammetric properties of acetonitrile solutions prepared from Et4N+ salts of clusters with R = Et and M = Mo, W are entirely consistent with the presence of bridged double cubanes in solution. Key observations include different chemical shifts of bridging and termi...
Incidence of Friend virus-induced polycythemia in splenectomized mice.

SummaryPolycythemia (HCT 58%) has been observed in splenectomized Ha/ICR (18%) and DBA/2 (16%) mice infected with a polycythemia-inducing strain (Mirand) of Friend virus. Data presented indicate that hepatic erythropoiesis, perhaps stimulated by the observed elevations in plasma ESF during the postinfection anemia, contributes significantly to the polycythemia. The polycythemic response appears more contingent on the presence of an expandable erythropoietic tissue than on the presence of the spleen per se.The participation of J. Jividen, A. Bulba, R, Kirchmyer, D. Mickens, and D. Mason is gratefully acknowledged.
Memory, brain and aging: The good, the bad and the promising

A large body of evidence converges on the conclusion that episodic memory (the recollection of personally experienced events) is the only long-term memory system that shows significant age-related deficits. Moreover, the brain regions most likely to show age-related volume loss are those most critically involved in episodic memory. Older adult brains may have much greater plasticity (capacity to change) than once believed; for example, neurogenesis (the birth of new neurons), increases in cognitive (including memory) performance, and increases in regional brain volume have all been shown to occur in older adulthood, as a result of physical or mental activity/training. The next wave of research will enhance our understanding of brain plasticity in adulthood and enable specific guidelines for lifestyle or pharmacological treatments that optimize brain and memory functioning well into late adulthood.
Identification of the Major Phosphorylation Site in Bcl-xL Induced by Microtubule Inhibitors and Analysis of Its Functional Significance

Vinblastine and other microtubule inhibitors used as antimitotic cancer drugs characteristically promote the phosphorylation of the key anti-apoptotic protein, Bcl-xL. However, putative sites of phosphorylation have been inferred based on potential recognition by JNK, and no direct biochemical analysis has been performed. In this study we used protein purification and mass spectrometry to identify Ser-62 as a single major site in vivo. Site-directed mutagenesis confirmed Ser-62 to be the site of Bcl-xL phosphorylation induced by several microtubule inhibitors tested. Vinblastine-treated cells overexpressing a Ser-62 → Ala mutant showed highly significantly reduced apoptosis compared with cells expressing wild-type Bcl-xL. Co-immunoprecipitation revealed that phosphorylation caused wild-type Bcl-xL to release bound Bax, whereas phospho-defective Bcl-xL retained the ability to bind Bax. In contrast, phospho-mimic (Ser-62 → Asp) Bcl-xL exhibited a reduced capacity to bind Bax. Functional tests were performed by transiently co-transfecting Bax in the context of different Bcl-xL mutants. Co-expression of wild-type or phospho-defective Bcl-xL counteracted the adverse effects of Bax expression on cell viability, whereas phospho-mimic Bcl-xL failed to provide the same level of protection against Bax. These studies suggest that Bcl-xL phosphorylation induced by microtubule inhibitors plays a key pro-apoptotic role at least in part by disabling the ability of Bcl-xL to bind Bax.
Effects of conservation tillage on the performance of Lake Erie basin farms.

This paper summarizes research that investigates the effects of alternative farming practices on the performance of Lake Erie basin farms. First, data from a representative panel of about 100 farmers is analyzed to determine how conservation tillage, rotations, and other factors affected farms' economic returns during 1987-1992. Statistical analysis of these data is unable to demonstrate that there is any significant relationship between farming system (i.e., tillage and rotation) variables and farm profitability. Next, a farm-level bioeconomic simulation model is used to analyze the effects of conservation tillage adoption on farm profitability, farm size, and pollutant emissions. Findings are that tillage system, farm size, and crop selection are determined jointly and may substantially improve economic performance of farms. Conservation tillage enables farms to be larger and more specialized, and as a result, farm profitability improves. Statistical analysis of farm panel data is unable to show the effect of tillage on profitability because it neglects to account for endogeneity of variables (or joint effects of tillage, size, crop selection, and performance) in production decisions.
Stimuli that enhance IgA class switching increase histone 3 acetylation at S alpha, but poorly stimulate sequential switching from IgG2b.

Germ-line (GL) α transcription can be induced in mouse splenic B cells by LPS and TGF-β. This stimulation results in ∼1% IgA+ cells, which can be increased by IL-4, IL-5, and anti-IgD dextran (αδDex). To determine the mechanism of this increase, we asked whether IgA class switching correlates with acetylation of histone 3 at Sα, the switch region for IgA. In the presence of the survival factor B lymphocyte stimulator (BLyS), acetylated histone 3 (AcH3) at Sα was changed little by TGF-β in LPS-stimulated mouse splenic B cell cultures, despite induction of GLα RNA. Compared with BLyS/LPS/TGF-β alone, treatment with BLyS/LPS/TGF-β/IL-4/IL-5/αδDex increased AcH3 at Sα fourfold, and also increased GLα RNA levels more than eightfold. By contrast, IgG2b class switching was optimal in BLyS/LPS/TGF-β alone, and was suppressed by IL-4/IL-5/αδDex. Thus, B cell activators that increase IgA class switching do not increase IgG2b class switching. Further investigation showed that in contrast to purified IgM+ cells, IgG2b+ cells switched poorly to IgA in response to BLyS/LPS/TGF-β/IL-4/IL-5/ ± αδDex. These results suggest that IgA class switching is unusual among isotypes in its requirement for multiple B cell activation signals in addition to LPS and the cytokine that initiates the corresponding GL transcription.
On modeling changes in food and biosolids at and around their glass transition temperature range

Temperature-induced mechanical and other changes in biosolids are regulated by three types of kinetics, depending on whether the material is in the glassy state, undergoing a transition, or fully plasticized. The transition itself can take place over a considerable temperature range, which in many food and biological systems happens to be the most pertinent to their functionality and stability. At the transition onset, the plot of stiffness vs. temperature has a downward concavity. It is reversed only at an advanced stage of plasticization after much of the stiffness has already been lost. Consequently, the WLF, Arrhenius, or any other model that implies a continuous upward concavity cannot account for changes in the transition region, and it is unsafe to use them to predict properties through extrapolation. The mechanical changes in the transition region can be described by a model with the mathematical structure of Fermi's function. Its applicability has been demonstrated with published data on a variety of foods and biosolids. Because the plot of stiffness vs. moisture, or water activity, has the same general shape as that of the stiffness vs. temperature plot, it too can be described by a model with the same mathematical format. Because moisture lowers the transition center temperature in a manner that can be described by a simple algebraic expression, the combined effects of temperature and moisture can be incorporated into a single general model. The latter can be used to create three-dimensional displays of the stiffness-temperature-moisture characteristic relationships of biosolids at and around their transition. At temperatures well above that of the transition, though, where a plot of log stiffness vs. temperature has a clear upper concavity, this model is no longer applicable, and the changes are better described by the WLF or an alternative model.
Asymptotic analysis considerations on the initial postbuckling behavior of delaminated composites

An asymptotic analysis for the initial postbuckling behavior of delaminated beam/plates is performed. Under the assumptions of inextensional deformation, the exact expressions that govern the plane elastic deformation of the different parts of the system are expanded in a Taylor series in terms of the distortion variable. Order of magnitude arguments are used to relate the distortion variables and these are subsequently used in an asymptotic solution for the deflections and the load. Finally, a comparison with experiments is performed.
SELECTIVE PULMONARY VASODILATION AND PULMONARY DISTRIBUTION OF RADIOLABELED HISTAMINE DURING LIQUID VENTILATION (LV) IN HYPOXIC NEWBORN (NB) LAMBS † 2336

Histamine (H) is a selective pulmonary vasodilator in the fetus and NB. During total LV (TLV), significant decreases in pulmonary artery pressure(Ppa) without systemic effects have been reported during hypoxia-induced pulmonary hypertension following intravenous (IV) and pulmonary administration of drug (PAD) delivering equal doses of H, however during partial liquid ventilation (PLV) there were no PAD effects. To test the hypothesis that differences in the homogeneity of drug distribution within the lung contribute to the differences in PAD effects of H during PLV compared to TLV, we compared both the pulmonary and systemic vascular effects and the pulmonary distribution of H following PAD delivery of 0.05 μg/kg as 0.5cc/kg bolus at the beginning of inspiration during PLV and TLV. NB lambs (n=14) were studied(2.5-5.0 kg) during hypoxia (PaO2:20-35 mm Hg) during both PLV and TLV, using a perfluorochemical (PFC) (LiquiVent®). Ppa and systemic arterial pressure (SAP) were continuously monitored; physiologic pH and normocarbia were maintained. Radiolabeled (3H) histamine was delivered to randomly selected animals in a supine position using PAD delivery during TLV and PLV. Lungs were hung and dried with continuous distending pressure of 30 cm H2O and sectioned using a standardized matrix method; samples were weighed, digested and radioactivity counted. Pulmonary distribution was assessed by normalizing the radioactivity of each piece (per dry weight) to the average radioactivity of all pieces in ratio form (uniform distribution resulting in a value of one for each piece) and all ratios were expressed in histogram form. During TLV, PAD H decreased Ppa significantly (p<0.02) and SAP did not change. During PLV, PAD H did not change Ppa or SAP. Representative distribution data using PAD during TLV resulted in 48% of pieces having ratio values between 0.8-1.2. Using PAD during PLV resulted in 14% of samples having ratio values between 0.8-1.2. We conclude that PAD delivery of H during TLV is an effective way of achieving pulmonary selective decreases in vascular pressure, due in part to more homogeneous distribution within the lung. We speculate that alternative techniques for drug delivery with liquid ventilation, such as creating a suitable emulsion of drug in PFC liquid for delivery with the initial fill of the lung, may allow improved pulmonary distribution of drug during both PLV and TLV. (Supp in part by Alliance Pharm Comp and Wyeth Pharm)
Phorbol 12-myristate 13-acetate stimulates proliferation and ductal morphogenesis and inhibits functional differentiation of normal rat mammary epithelial cells in primary culture.

The effect of the tumor promoter phorbol 12-myristate 13-acetate (PMA) on proliferation and differentiation of normal mammary epithelial cells from 50-day-old virgin rats was investigated using a model system that allows for full morphological and functional development of the cells. In this model, mammary epithelial cells are grown within a reconstituted basement membrane in a defined serum-free medium. PMA at a concentration of 10−6 M effected translocation of protein kinase C from cytosol to membrane. At the same concentration, it stimulated cell proliferation both in the presence and absence of EGF, and this stimulation was observed even when PMA exposure was limited to 15 min at the time of each media change. In contrast to the effect on proliferation, PMA at concentrations of 10−7 and 10−6 M inhibited functional differentiation as assessed by casein accumulation. Phorbol 12,13-dibutyrate at 10−6 M also stimulated proliferation and inhibited casein accumulation and was more effective than PMA in both cases. In contrast, the nonactive tumor promoter 4-α PMA had no effect on either proliferation or differentiation. One of the most striking effects of PMA was its ability to stimulate an atypical ductal morphogenesis, as manifested by the formation of intricate web-like colonies, and to inhibit the development of the well-differentiated alveolar-like multilobular colonies. PMA was also shown to completely suppress the growth of the squamous-like colonies that develop when EGF is absent or deficient. These effects of phorbol esters in mammary epithelial cells to stimulate proliferation, inhibit functional differentiation, and stimulate the development of ductal colonies are consistent with the suggestion that the signal transduction pathways evoked by PMA could act to stimulate the growth of initiated cells or render normal cells more sensitive to carcinogen. © 1994 Wiley-Liss, Inc.
Propagation of protein glycation damage involves modification of tryptophan residues via reactive oxygen species: inhibition by pyridoxamine.

Abstract Nonenzymatic modification of proteins is one of the key pathogenic factors in diabetic complications. Uncovering the mechanisms of protein damage caused by glucose is fundamental to understanding this pathogenesis and in the development of new therapies. We investigated whether the mechanism involving reactive oxygen species can propagate protein damage in glycation reactions beyond the classical modifications of lysine and arginine residues. We have demonstrated that glucose can cause specific oxidative modification of tryptophan residues in lysozyme and inhibit lysozyme activity. Furthermore, modification of tryptophan residues was also induced by purified albumin–Amadori, a ribose-derived model glycation intermediate. The AGE inhibitor pyridoxamine (PM) prevented the tryptophan modification, whereas another AGE inhibitor and strong carbonyl scavenger, aminoguanidine, was ineffective. PM specifically inhibited generation of hydroxyl radical from albumin–Amadori and protected tryptophan from oxidation by hydroxyl radical species. We conclude that oxidative degradation of either glucose or the protein–Amadori intermediate causes oxidative modification of protein tryptophan residues via hydroxyl radical and can affect protein function under physiologically relevant conditions. This oxidative stress-induced structural and functional protein damage can be ameliorated by PM via sequestration of catalytic metal ions and scavenging of hydroxyl radical, a mechanism that may contribute to the reported therapeutic effects of PM in the complications of diabetes.
Identification Of Small Molecule TRABID Deubiquitinase Inhibitors By Computation-Based Virtual Screen

Background Wnt/β-catenin-mediated gene transcription plays important roles in a wide range of biological and pathophysiological processes including tumorigenesis where β-catenin-mediated transcription activity frequently elevates. TRABID, a deubiquitinase, was shown to have a positive Wnt/β-catenin-mediated gene transcription and hence holds a promise as a putative anti-cancer target.
Using spring repulsions to model entanglement interactions in Brownian dynamics simulations of bead–spring chains

We develop a bead–spring Brownian dynamics model for simulating the topological interactions between polymers and thin obstacles and apply this method to electrophoretically translating DNA strands interacting with an immovable post. The use of a bead–spring method allows for the simulation of entanglement interactions of polymer chains too long to be simulated using bead–rod or pearl necklace models. Using stiff “FENE-Fraenkel” springs, we are able to model short chains as well. Our new method determines the shortest distance between a spring and the post, calculates a repulsive force inversely related to this distance using an exponential potential, and corrects for the rare situation when a spring passes beyond the post despite the repulsive interaction. As an example problem, we consider single-chain collisions with a single post in weak electric fields. We explore a wide range of chain lengths (25–1,515 Kuhn steps), and we find that the average delay produced by the collision is a function of both the chain length and the Peclet number. Chains of all lengths reach the same upper limit at high Peclet number, but they follow separate curves with similar slopes at lower Peclet number. Our results are consistent with published results for a 25-Kuhn-step chain at Peclet number Pe = 10. Our new method is a general one that allows us to compute the effects of entanglements in systems with rare entanglements and long chains that cannot be simulated by other more microscopic methods.
Excretion of Fluorescein in the Urine of Women With Interstitial Cystitis

AbstractPurpose: Altered bladder permeability may have a role in the pathogenesis of interstitial cystitis. Fluorescein, a fluorescent dye of molecular weight 325, has been used to assess membrane permeability. Orally ingested fluorescein normally is rapidly conjugated to glucuronate by the liver and excreted in the urine.Materials and Methods: To test its use as a marker of bladder permeability, we administered fluorescein orally to 6 patients with interstitial cystitis who satisfied National Institutes of Health, National Institute for Diabetes and Digestive and Kidney Diseases criteria and to 6 normal female control subjects. After emptying the bladder and collection of a baseline blood sample, fasted subjects ingested 20 mg. fluorescein and blood samples were collected 1, 2, 3, 4 and 24 hours later. Urine was collected during each of the first 4 hours, and then from 4 to 10, 10 to 16 and 16 to 24 hours. Urine volume was measured, and all plasma and urine samples were analyzed for fluorescein.Results: ...
Mental Health Characteristics of Social Work Students: Implications for Social Work Education

No studies have examined to date the mental health and substance use characteristics of social work students. Therefore, this study was undertaken to describe and identify these characteristics among a sample of social work students located in a Florida school of social work. Results indicated that approximately 34% of the participants reported high levels of depressive symptoms, 12% had a history of suicidal ideation, and 4% reported having thought about suicide recently. Six percent reported high levels of post-traumatic stress disorder symptomatology, and 3% were highly likely to have a dissociative disorder. High proportions of the students reported having multiple traumatic experiences. Students in this sample were less likely to report lifetime or current alcohol or marijuana use than national college student samples, but more likely to report lifetime or current use of illicit substances other than marijuana.
Pulmonary alveolar proteinosis and pulmonary cryptococcosis in an adolescent boy

A 14-year-old boy received massive lung lavage for pulmonary alveolar proteinosis after transtracheal catheter lavage was ineffective in alleviating progressive respiratory failure. He then developed widespread pulmonary cryptococcosis which was apparently eradicated by the administration of amphotericin B. Two years later, both lungs were again washed because of rapidly decreasing vital capacity. Presently, at age 17 years, he appears healthy although pulmonary function is less than normal.
A finite element approach for prediction of aerothermal loads

A Taylor-Galerkin finite element approach is presented for analysis of high speed viscous flows with an emphasis on predicting heating rates. Five computational issues relevant to the computation of steady flows are examined. Numerical results for supersonic and hypersonic problems address the computational issues and demonstrate the validity for the approach for analysis of high speed flows.
Using Local Correlation to Explain Success in Baseball

Statisticians have long employed linear regression models in a variety of circumstances, including the analysis of sports data, because of their flexibility, ease of interpretation, and computational tractability. However, advances in computing technology have made it possible to develop and employ more complicated, nonlinear, and nonparametric procedures. We propose a fully nonparametric nonlinear regression model that is associated to a local correlation function instead of the usual Pearson correlation coefficient. The proposed nonlinear regression model serves the same role as a traditional linear model, but generates deeper and more detailed information about the relationships between the variables being analyzed. We show how nonlinear regression and the local correlation function can be used to analyze sports data by presenting three examples from the game of baseball. In the first and second examples, we demonstrate use of nonlinear regression and the local correlation function as descriptive and inferential tools, respectively. In the third example, we show that nonlinear regression modeling can reveal that traditional linear models are, in fact, quite adequate. Finally, we provide a guide to software for implementing nonlinear regression. The purpose of this paper is to make nonlinear regression and local correlation analysis available as investigative tools for sports data enthusiasts.
Factor Reallocation and Growth in Developing Coutries

This paper examines the extent to which developing countries benefit from intersectoral factor transfers by specifying the impact and determinants of sectoral changes and of the degree of dualism (or allocation inefficiency) in a dual economy model. Conditions under which factor reallocation is growth-enhancing are derived. An empirical error-correction equation is estimated for 30 developing countries during 1965-80. Results suggest that labor reallocation effects are especially important in countries with high rates of investment (and thus high rates of labor transfer) and/or at low levels of development (and thus high degrees of dualism).
Acquired interferon gamma responsiveness during Caco-2 cell differentiation: effects on iNOS gene expression.

BACKGROUND—Impairment of intestinal barrier function occurs under a variety of inflammatory conditions and is mediated at least in part by interferon γ (IFN-γ) induced nitric oxide (NO) production. Previous in vivo studies have shown that systemic lipopolysaccharide treatment caused an induction of the rat inducible nitric oxide synthase (iNOS) mRNA primarily in villus cells, rather than in undifferentiated crypt cells. AIMS—To examine iNOS induction by IFN-γ in vitro as a function of enterocyte differentiation. METHODS—Preconfluent and postconfluent Caco-2 cells were treated with IFN-γ in the presence or absence of various inhibitors. Northern analyses were performed to assess the magnitude of iNOS mRNA induction. IFN-γ receptor mRNA and protein levels were determined. RESULTS—iNOS mRNA induction by IFN-γ occurred at two hours and was not blocked by cycloheximide, indicating that it is an immediate early response. iNOS induction and nitrite/nitrate increases were inhibited by dexamethasone and pyrrolidine dithiocarbamate, supporting an important role for the NF-κB transcription factor in this process. The stimulated iNOS induction was seen almost exclusively under conditions of cellular differentiation—that is, in postconfluent Caco-2 cells. This increased IFN-γ responsiveness seen in postconfluent Caco-2 cells correlated with an increased expression of IFN-γ receptor, whereas T84 and HT-29 cells did not show any significant alterations in either iNOS induction or IFN-γ receptor levels as a function of postconfluent growth. CONCLUSIONS—With regard to iNOS mRNA induction, IFN-γ responsiveness is acquired during Caco-2 cell differentiation, perhaps related to an increase in the numbers of IFN-γ receptors. Keywords: interferon γ receptor; nitric oxide synthase; intestinal epithelium; inflammation
Compliance to threat as a function of knowledge of the sources’ prior losses

The present research investigated compliance to a threat as a function of the threatener’s previous experience with another person. The subjects played four separate blocks of trials of Prisoner’s Dilemma games. Partners (always fictitious) supposedly were changed from Block 2 to Block 3. Results indicated that when a threat was received prior to the start of Block 3, it was effective in increasing cooperative behavior only when the subject knew that the source had incurred losses during Block 2. In addition, this greater increase in cooperative responding was maintained when the possibility of incurring punishment was subsequently removed in Block 4. Results suggested that the source’s prior losses gave justification to this use of threat and, therefore, increased compliance.
Dynamic Control of Protein−Protein Interactions

The capability to selectively and reversibly control protein−protein interactions in antibody-doped polypyrrole (PPy) was accomplished by changing the voltage applied to the polymer. Polypyrrole was doped with sulfate polyanions and monoclonal anti-human fibronectin antibodies (αFN). The ability to toggle the binding and dissociation of fibronectin (FN) to αFN-doped polypyrrole was demonstrated. Staircase potential electrochemical impedance spectroscopy (SPEIS) was performed to characterize the impedance and charge transfer characteristics of the αFN-doped PPy as a function of applied voltage, frequency, and FN concentration. Impedance measurements indicated oxidation of αFN-doped PPy promoted selective binding of FN to αFN antibodies and reduction of the polymer films facilitated FN dissociation. Moreover, SPEIS measurements suggested that the apparent reversibility of antigen binding to antibody-doped PPy is not due to the suppression of hydrophobic binding forces between antibody and antigen. Instead, ...
Action potential alternans and irregular dynamics in quinidine-intoxicated ventricular muscle cells. Implications for ventricular proarrhythmia.

BACKGROUNDCardiac cells display rate-dependent beat-to-beat variations in action-potential duration (APD), action potential amplitude (APA), and excitability during periodic stimulation. We hypothesized that quinidine causes a marked increase in the variability of APD, APA, and excitability of ventricular cells isolated from quinidine-toxic, arrhythmic ventricles.METHODS AND RESULTSAction potentials were recorded from right ventricular endocardial tissues (2 x 1 cm, < 2 mm thick) isolated from dogs in which ventricular tachycardia and ventricular fibrillation (VT/VF) were induced with intravenous quinidine (80-100 mg/kg) over a 5-hour period in vivo (n = 7). As the basic cycle length (BCL) of stimulation was progressively shortened, rate-dependent variations in APD and APA occurred. The initial dynamic change was alternans of APD and APA that could be either in or out of phase between two cells. The magnitude of alternans was a function of the BCL and the strength of the stimulation current. At critically...
Human XPA and XRCC1 DNA Repair Proteins Expressed in Yeast, Saccharomyces cerevisiae

Abstract Human XPA and XRCC1 DNA repair proteins have been expressed in a series of novel yeast episomal vectors. Expression of XPA cDNA resulted in synthesis of anti-XPA crossreacting polypeptides of 40 and 42 kDa, the status of the native protein found in human cells. Likewise, the majority of the recombinant XRCC1 found in the yeast intracellular fraction corresponded to the molecular mass of the full-length human protein. Recombinant XPA protein expressed as an NH 2 -terminal polyhistidine fusion could be affinity purified using Ni 2+ agarose.
Aseptic Tibial Debonding as a Cause of Early Failure in a Modern Total Knee Arthroplasty Design

Background We observed isolated tibial component debonding from the cement in one modern primary TKA design (NexGen LPS 3° tibial tray; Zimmer, Warsaw, IN, USA). This failure mechanism is sparsely reported in the literature.
Earlobe creases in a cohort of elderly veterans.

Two-hundred thirty-four residents (220 male, 14 female) of a Veterans Administration Nursing Home and a Hospital Based Home Care program, 24–99 years old (mean 66), were examined for the presence (or absence) of earlobe creases and their correlation with cardiovascular disease. Unilateral or bilateral earlobe creases were found in 119 patients (55 unilateral, 64 bilateral), or 50.85 per cent. One hundred forty-two patients had one or more forms of cardiovascular disease: 20 had coronary artery disease, 45 had cerebrovascular disease, 12 had peripheral vascular disease, 48 had atherosclerotic heart disease and/or hypertension, and 17 had “other” cardiovascular disease, mostly congestive heart failure. Seventy-three of them (51.4 per cent) had earlobe creases. The rest—92 patients—had no clinically apparent cardiovascular disease, and the incidence of earlobe creases in this group was 50 per cent. Cross-tabulation (chi square) and multivariate (stepwise logistic) regression analyses relating the presence (or absence) of earlobe creases to diagnosis, age, sex, smoking, body weight, height, blood pressure, serum cholesterol, glucose, urea nitrogen, creatinine, uric acid, calcium, phosphorus, albumin, and hemoglobin revealed no significant correlation between the presence of earlobe creases and any of the above parameters. Earlobe creases were present in about half the study group regardless of diagnosis, and only about half the patients with cardiovascular and coronary artery disease had earlobe creases. It was concluded that in our patient population earlobe creases were not specifically associated with cardiovascular disease, as they were associated about equally with both cardiovascular and noncardiovascular disease. Their significance in the diagnosis of coronary artery disease may be greater in a younger age group, because in the elderly these creases may occur as part of skin aging, and they may also accompany noncardiovascular diseases.
Local heat transfer and hot-spot factors in wire-wrap tube bundle

Heat transfer coefficients and hot-spot factors have been determined from measured local temperatures and calculated local mass flux in seven adjacent tubes and associated subchannels of a 61 wire-wrap tube bundle characteristic of the blanket of a GCFR (Gas Cooled Fast Reactor). The bundle consisted of 2.11 cm OD stainless steel tubes on a triangular array with a pitch/diameter ratio of P/D = 1.05. The helical wire of 0.1067 cm in diameter was coiled on the tube with a respective initial orientation of 0–120–240°C and 30.48 cm helical pitch. The experiment used water at atmospheric pressure and temperature as coolant. The resulting dimensionless correlation for heat transfer is applicable to gases and all non-metal fluids in one phase flow when the fluid properties at subchannel bulk temperature are used. This correlation is based on local subchannel mass flux and is applicable to all wire-wrap configurations. Local subchannel mass fluxes were determined with a computer program COBRA IV and used to correlate the average Nusselt number for each subchannel in terms of local Reynolds number and fluid Prandtl number. The differences of up to 19% between that correlation and the one presented in earlier work are discussed in the text. The hot-spot factors on the convective heat transfer coefficient for tubes and subchannels are given as a function of Reynolds number based on a bundle average mass flux and a local subchannel hydraulic diameter. These factors are specific to the bundle configuration and are also dependent on the wire-wrap configuration.
Behavioral Activation as a Treatment for Geriatric Depression

By encouraging older adults to become more active, behavioral activation (BA) may help reduce depressive symptoms brought on by activity restriction. The purpose of this study was to determine, through a multiple-baseline design, whether BA could be successfully applied to older adults with depression. Nine depressed older adults (M = 75 years of age) underwent a course of in-home BA therapy (mean number of sessions = 14.7). Overall, participants' Geriatric Depression Scale and Hamilton Rating Scale for Depression scores decreased from pre- to post-treatment, and 71% of participants no longer met criteria for a depressive disorder. Behavioral activation shows promise as a treatment for geriatric depression.
Application of the Alvarez-Humphrey concept to the design of a miniaturized scanning microscope

This paper contains two optical designs that utilize the Alvarez-Humphrey surfaces to provide the miniature multi-modal microscope (4M device) with the additional capability of imaging different object depths onto the same image plane. The Alvarez-Humphrey surfaces are a pair of conjugate, rotationally asymmetrical, aspheric surfaces such that, the lateral movement of these surfaces across the optical axis, results in an element of variable optical power. The first design is a direct application of the Alvarez-Humphrey concept to the 4M device. However, due to the inadequate imaging performance and unavailability of space for the actuator due to proximity of the Alvarez Plates, a second design was created. The Separated Alvarez Plate Design is a unique design involving two conjugate pairs of Alvarez-Humphrey surfaces. The lateral movement of the central element changes the optical power. However, due to the symmetry of the system and the incorporation of the theoretical work done on induced aberration correction, this system has far superior performance. It also has adequate space for the actuator due to the separation of the elements.
Distribution of Radioactivity in Pelagic Clays

An attempt is made to study the localization of radioelements in different mineral phases of pelagic clay sediments. The results so far obtained indicate that the ionium supported radium is redistributed by diffusion through the interstitial solution and that the authigenic zeolite phillipsite plays an important role as a scavenger of radioelements within the deposit. The mechanism of transfer of radioelements from the ocean to pelagic deposits is discussed, and points of uncertainty in the interpretation of the distribution of gross beta-activity are indicated. DOI: 10.1111/j.2153-3490.1955.tb01156.x
Petri nets: An examination of a versatile modeling tool

The features of Petri nets that make them useful as models of large and complex systems-especially high-speed computers possessing a large number of interactive components, concurrency and synchronization problems-are outlined, as well as their limitations. The structure of a Petri net is explained, and the role of interpretation in modeling is discussed. Marked Petri nets and their features are examined. The historical development of Petri nets is briefly addressed.
Testing for Genetic Linkage in Families by a Variance-Components Approach in the Presence of Genomic Imprinting

Some genes that affect development and behavior in mammals are known to be imprinted; and ⩾1% of all mammalian genes are imprinted. Hence, incorporating an imprinting parameter into linkage analysis may increase the power to detect linkage for these traits. Here we propose theoretical justifications for a recently developed model for testing of linkage, in the presence of genetic imprinting, between a quantitative-trait locus and a polymorphic marker; this is achieved in the variance-components framework. We also incorporate sex-specific recombination fractions into this model. We discuss the effects that imprinting and nonimprinting have on the power of the usual variance-components method and on the variance-components method that incorporates an imprinting parameter. We provide noncentrality parameters that can be used to determine the sample size necessary to attain a specified power for a given significance level, which is useful in the planning of a linkage study. Optimal strategies for a genome scan of potentially imprinted traits are discussed.
Mathematical Modeling for Modal Computations Concerning a Morphable Wing

This Note serves to offer an analytical method of describing the evolution of the natural frequencies and mode-shapes characteristic of an adaptable wing during an arbitrary actuation cycle. Although inherently simplified, the resulting method is seen to be well suited for direct application in the theoretical analysis of the aeroelastic stability of such structures.
Habitat context influences predator interference interactions and the strength of resource partitioning

Despite increasing evidence that habitat structure can shape predator-prey interactions, few studies have examined the impact of habitat context on interactions among multiple predators and the consequences for combined foraging rates. We investigated the individual and combined effects of stone crabs (Menippe mercenaria) and knobbed whelks (Busycon carica) when foraging on two common bivalves, the hard clam (Mercenaria mercenaria) and the ribbed mussel (Geukensia demissa) in oyster reef and sand flat habitats. Because these species co-occur across these and other estuarine habitats of varying physical complexity, this system is ideal for examining how habitat context influences foraging rates and the generality of predator interactions. Consistent with results from previous studies, consumption rates of each predator in isolation from the other were higher in the sand flat than in the more structurally complex oyster reef habitat. However, consumption by the two predators when combined surprisingly did not differ between the two habitats. This counterintuitive result probably stems from the influence of habitat structure on predator-predator interactions. In the sand-flat habitat, whelks significantly reduced their consumption of their less preferred prey when crabs were present. However, the structurally more complex oyster reef habitat appeared to reduce interference interactions among predators, such that consumption rates when the predators co-occurred did not differ from predation rates when alone. In addition, both habitat context and predator-predator interactions increased resource partitioning by strengthening predator dietary selectivity. Thus, an understanding of how habitat characteristics such as physical complexity influence interactions among predators may be critical to predicting the effects of modifying predator populations on their shared prey.
Medicolegal Issues Relating to Herniorrhaphy

Patients who have been operated on for an abdominal wall hernia are not generally as litigious as some other categories of surgical patients. The major reason is, of course, that most patients obtain an excellent result from herniorrhaphy and are grateful to their surgeon for making them feel structurally intact again. There are exceptions, however, and surgeons who perform abdominal wall reconstruction face the same potential liability allegations as other surgeons. Unfortunately, surgical procedures are viewed as a consumer product to be purchased like any business commodity under a warranty that can be exercised any time the result is perceived by the consumer to be different from that expected.
The steady-state flow pattern past gravitating bodies

Gravitating bodies significantly alter the flow pattern (density and velocity) of the gas that attempts to stream past. Still, small protoplanets in the Mars–super-Earth range can only bind limited amounts of nebular gas; until the so-called critical core mass has been reached (�1–10 Earth masses) this gas is in near hydrostatic equilibrium with the nebula. Here we aim for a general description of the flow pattern surrounding these low-mass, embedded planets. Using various simplifying assumptions (subsonic, 2D, inviscid flow, etc), we reduce the problem to a partial differential equation that we solve numerically as well as approximate analytically. It is found that the boundary between the atmosphere and the nebula gas strongly depends on the value of the disc headwind (deviation from Keplerian rotation). With increasing headwind the atmosphere decreases in size and also becomes more asymmetrical. Using the derived flow pattern for the gas, trajectories of small solid particles, which experience both gas drag and gravitational forces, are integrated numerically. Accretion rates for small particles (dust) are found to be low, as they closely follow the streamlines, which curl away from the planet. However, pebble-size particles achieve large accretion rates, in agreement with previous numerical and analytical works.
CBCT in orthodontics: assessment of treatment outcomes and indications for its use

Since its introduction into dentistry in 1998, CBCT has become increasingly utilized for orthodontic diagnosis, treatment planning and research. The utilization of CBCT for these purposes has been facilitated by the relative advantages of three-dimensional (3D) over two-dimensional radiography. Despite many suggested indications of CBCT, scientific evidence that its utilization improves diagnosis and treatment plans or outcomes has only recently begun to emerge for some of these applications. This article provides a comprehensive and current review of key studies on the applications of CBCT in orthodontic therapy and for research to decipher treatment outcomes and 3D craniofacial anatomy. The current diagnostic and treatment planning indications for CBCT include impacted teeth, cleft lip and palate and skeletal discrepancies requiring surgical intervention. The use of CBCT in these and other situations such as root resorption, supernumerary teeth, temporomandibular joint (TMJ) pathology, asymmetries and alveolar boundary conditions should be justified on the basis of the merits relative to risks of imaging. CBCT has also been used to assess 3D craniofacial anatomy in health and disease and of treatment outcomes including that of root morphology and angulation; alveolar boundary conditions; maxillary transverse dimensions and maxillary expansion; airway morphology, vertical malocclusion and obstructive sleep apnoea; TMJ morphology and pathology contributing to malocclusion; and temporary anchorage devices. Finally, this article utilizes findings of these studies and current voids in knowledge to provide ideas for future research that could be beneficial for further optimizing the use of CBCT in research and the clinical practice of orthodontics.
Moral Knowing in a Hindu Sacred City: An Exploration of Mind, Emotion, and Self

Moral Knowing in a Hindu Sacred City: An Exploration of Mind, Emotion, and Self. STEVEN M. PARISH. New York: Columbia University Press, 1994. xii + 342 pp., maps, photographs, notes, glossary, bibliography, index.
Preschoolers' conceptual and acoustic encoding as evidenced by release from PI

Two experiments demonstrated the feasibility of using the release from proactive interference (PI) technique with preschool children. In Experiment I, release from PI was found using pictures from the same taxonomic category. Experiment II demonstrated encoding based on acoustic qualities using oral presentation of common rhyming words.
Generational Shifts in Language Use Among US Latinos: Mobility, Education and Occupation

The role of language and linguistic assimilation among Latinos has a direct impact on both education and occupation in terms of social mobility. The relationship can be examined with a generational context as language usage changes from first generation immigrants to third generation immigrants. The specific question being addressed herein is whether language or ethnicity had more impact on Latinos’ mobility in terms of educational achievement and occupational prestige. Results presented in this paper imply the importance and impact of the maximization of the accumulation of linguistic capital in order to accelerate the acquisition of educational attainment.