cssi/SciSciGPT-SciSciNet huggingface dataset:
Modelling and experimental study of coupled exchange of p,p′‐DDE and colloids in a flume simulated stream–streambed system

Stream–subsurface exchange plays a significant role in the fate and transport of contaminants in streams. It has been modelled explicitly by considering fundamental processes such as hydraulic exchange, colloid filtration, and contaminant interactions with streambed sediments and colloids. The models have been successfully applied to simulate the transport of inorganic metals and nutrients. In this study, laboratory experiments were conducted in a recirculating flume to investigate the exchange of a hydrophobic organic contaminant, p,p′-dichloro-diphenyl-dichloroethane (DDE), between a stream and a quartz sand bed. A previously developed process-based multiphase exchange model was modified by accounting for the p,p′-DDE kinetic adsorption to and desorption from the bed sediments/colloids and was applied to interpret the experimental results. Model input parameters were obtained by conducting independent small-scale batch experiments. Results indicate that the immobilization of p,p′-DDE in the quartz sand bed can occur under representative natural stream conditions. The observed p,p′-DDE exchange was successfully simulated by the process-based model. The model sensitivity analysis results show that the exchange of p,p′-DDE can be sensitive to either the sediment sorption/desorption parameters or colloidal parameters depending on the experimental conditions tested. For the experimental conditions employed here, the effect of colloids on contaminant transport is expected to be minimal, and the stream–subsurface exchange of p,p′-DDE is dominated by the interaction of p,p′-DDE with bed sediment. The work presented here contributes to a better mechanistic understanding of the complex transport process that hydrophobic organic contaminants undergo in natural streams and to the development of reliable, predictive models for the assessment of impacted streams. Copyright © 2015 John Wiley & Sons, Ltd.
Effect of Vitamin D Deficiency on Mouse Mammary Gland and Milk

Lactational performance, milk composition, mammary calcium pools and serum calcium were examined in vitamin D-deficient lactating mice to determine whether the mammary gland is a target organ for vitamin D. CD1 mice were fed vitamin D-deficient or control diets containing 1.2% calcium and 0.5% phosphorus 8-12 weeks prior to breeding. Plasma calcium levels were within normal limits in all mice. Vitamin D deficiency was verified by lack of detectable serum 25-hydroxycholecalciferol. Deficient mice had fewer pups per litter than controls (7.1 +/- 0.5 vs. 8.4 +/- 0.3; P less than 0.05). Pups from vitamin D-deficient and repleted mothers grew at the same rate. Mammary tissue intracellular and extracellular calcium pools, measured by an efflux technique, did not differ in the two groups. Milk samples were collected by suction after injection of 0.1 IU of oxytocin i.p. or anaerobically by a surgical technique. Although protein, Na, K, ionized calcium and pH did not differ, milk from vitamin D-deficient mice had lower lactose (114.6 vs. 135.9 mM; P less than 0.02) and slightly lower calcium (66.8 vs. 75.4 mM; P less than 0.1) concentrations than controls. The data do not demonstrate any direct effects of vitamin D on mammary gland calcium metabolism.
Reciprocal Socialization: Rising Powers and the West

Maximillian Terhalle. (2011) Reciprocal Socialization. International Studies Perspectives, doi: 10.1111/j.1528-3585.2011.00442.x © 2011 International Studies Association This article asks how the international order can be renegotiated with rising powers. Negotiating understood as a process of socialization is the focus of the article. However, given non-Western states’ recent practice of powerfully permeating the existing Western order, it is difficult to explain this process by means of neorealist, constructivist, or liberal socialization. Respectively, they presuppose that some states are already socialized while others need to be adopted into the club of socialized members. In contrast, this article suggests the notion of reciprocal socialization. It explains how rising powers are socialized into the order, while reshaping it when they enter. Two conditions need to be fulfilled to accomplish a socializing process that reflects the reciprocal influencing of states of the Western security community and non-Western veto-players; these are employing “small informal groups” and “personalized interactions.” Their application can be viewed in informal operational rules which are, in turn, capable of governing the renegotiations.
Influence Of Holes On The In-Plane Tensile Strength And Fatigue Durability Of A NICALON(Trademark)/Si-N-C Ceramic Matrix Composite

Effects of different sizes of holes as well as different percentages of open areas on the in-plane tensile strength and fatigue durability of the SiC/Si-N-C composite were investigated in this study. Test specimens with no holes, four different diameters of holes (1.0 to 3.2 mm), and four different open areas (20 to 35%) were machined. All mechanical testing was performed in air at a temperature of 910 C. Fatigue tests were conducted with a load ratio, R = 0.05, and a frequency of 0.33 Hz. In general, both the in-plane tensile strength of the composite and its fatigue durability decreased with an increase in the size of the hole and percentage of the open area. Reductions in the in-plane tensile strength and cyclic fatigue life of the composite were described by empirical equations with the diameter of the hole and the percent open area as the independent variables. The validity of these two empirical equations was verified with additional tensile and fatigue test data generated on the composite specimens.
Characterization of Protein Targets of Mammalian Thioredoxin Reductases

Mammalian thioredoxin reductases (TRs) are members of the pyridine nucleotide-disulfide oxidoreductase family. The main function of these enzymes is to maintain thioredoxins (Trxs) in the reduced state. The accessibility and high reactivity of selenocysteine in the C-terminal tetrapeptide allows mammalian TRs to couple to a range of substrates from proteins, such as Trx, to small molecules, such as selenite and hydroperoxides. However, identification of physiological substrates of TRs remains a challenge, with new targets identified primarily by testing random candidates in in vitro assays. The reaction mechanism of TRs supports a procedure that could trap substrates in a covalent nonproductive complex with TRs. Accordingly, attachment of TRs to affinity matrices allows isolation and identification of these targets. Application of this method revealed that Trxs are the major targets of TRs and supported efficient isolation of Trx substrates on TR affinity columns. We suggest that this procedure may be used as a general method of affinity isolation of Trxs and other TR substrates.
d-Fructose 1-Phosphate Kinase and d-Fructose 6-Phosphate Kinase from Aerobacter aerogenes A COMPARATIVE STUDY OF REGULATORY PROPERTIES

Abstract d-Fructose 1-phosphate kinase from Aerobacter aerogenes was purified 315-fold, and its properties, regulation, and reaction kinetics were compared with those of d-fructose 6-phosphate kinase from the same organism. d-Fructose-6-P kinase exhibited a sigmoidal dependence of rate on d-fructose-6-P concentration, whereas d-fructose-1-P kinase exhibited hyperbolic dependence of rate on d-fructose-1-P concentration. The apparent Km of d-fructose-1-P kinase for either substrate (d-fructose-1-P or ATP) did not vary with the concentration of the other substrate, which indicates a sequential mechanism of substrate binding. ATP inhibited both enzymes when the ratios of Mg++ to ATP concentrations were below 2:1; ATP inhibition of d-fructose-6-P kinase was relieved by Mg++, d-fructose-6-P, ADP, and various other nucleoside diphosphates, whereas ATP inhibition of d-fructose-1-P kinase was relieved by Mg++ only. Both enzymes showed a sigmoidal dependence of rate on Mg++ concentration; increased levels of d-fructose-6-P shifted the d-fructose-6-P kinase curve from sigmoidal to hyperbolic, whereas d-fructose-1-P had no effect on a similar plot for d-fructose-1-P kinase. Other nucleoside triphosphates were used as phosphoryl donors by both enzymes and, unlike the situation with other described phosphofructokinases, inhibited activity when the ratios of Mg++ to nucleotide concentrations were below 2:1. In contrast with the result obtained with ATP, the inhibition of d-fructose-6-P kinase by other nucleoside triphosphates could not be relieved by d-fructose-6-P. The data indicate that, whereas d-fructose-6-P kinase exhibits allosteric properties and a regulatory pattern similar to those of d-fructose-6-P kinases from various other organisms, d-fructose-1-P kinase behaves more like a nonallosteric kinase. However, citrate (Ki 0.85 mm), d-fructose-1,6-di-P (Ki 4.4 mm), and d-fructose-6-P (Ki 1.0 mm) inhibited d-fructose-1-P kinase competitively with d-fructose-1-P, which suggests possible control of activity in vivo. The molecular weights of d-fructose-6-P kinase and d-fructose-1-P kinase were estimated to be 90,000 and 75,000, respectively. Other properties of the two phosphofructokinases, such as substrate specificity, Km values, pH optima, and stability, are also reported.
Image Enhancement, Image Quality, and Noise

The Multiscale Retinex With Color Restoration (MSRCR) is a non-linear image enhancement algorithm that provides simultaneous dynamic range compression, color constancy and rendition. The overall impact is to brighten up areas of poor contrast/lightness but not at the expense of saturating areas of good contrast/brightness. The downside is that with the poor signal-to-noise ratio that most image acquisition devices have in dark regions, noise can also be greatly enhanced thus affecting overall image quality. In this paper, we will discuss the impact of the MSRCR on the overall quality of an enhanced image as a function of the strength of shadows in an image, and as a function of the root-mean-square (RMS) signal-to-noise (SNR) ratio of the image.
Automation is the answer, but what is the question? Progress and prospects for Central and Eastern European Libraries

In the former Yugoslavia and Soviet Bloc countries of Central and Eastern Europe most information technology was unavailable, unaffordable or discouraged for forty years. These countries realise that they must improve their internal infrastructures if they are to become integral parts of the global information infrastructure. We report the results of a mail survey conducted in late 1994 and early 1995 of seventy research libraries in Croatia, Czech Republic, Hungary, Poland, Slovakia and Slovenia, building on the findings from interviews conducted with 300 persons in the region in 1993–1994. Results show that these libraries are acquiring automated processing systems, CD‐ROM databases, and connections to computer networks at a rapid rate and that automation activity has increased substantially since 1989; we report specific data on system implementation and network services by country and by type of library. ‘Access’ is their top reason to automate, which appears to mean placing the catalogue online with better search capabilities and putting items on the shelves faster — but does not necessarily mean improvements in self‐service for library users. Co‐operation and standards are highly‐ranked automation goals, yet we find anomalous results on each. Management goals focus more on speed and processing than on management information, staffing or advancing the mission of the parent organisation. Management of human resources ranks low, despite the need for wider staff involvement in the system selection process, education of technically‐trained library professionals, continuing training of staff and training of library users. We conclude with implications of these results for the region.
A solid-state emf study of ternary Ni-S-O, Fe-S-O, and quaternary Fe-Ni-S-O

Four two-phase equilibria in Ni-S-O, three two-phase equilibria in Fe-S-O, and one two-phase equilibrium and four three-phase equilibria in Fe-Ni-S-0 atPSO2 ≃ 1 atm were studied using the following emf cell: $$Pt, O_2 (air) \left| {\begin{array}{*{20}c} {ZrO_2 \cdot CaO or} \\ {ZrO_2 \cdot Y_2 O_3 } \\ \end{array} } \right|\begin{array}{*{20}c} {mixture of phases, Au} \\ {SO_2 , S_2 , O_2 , SO_3 with P_T \simeq 1 atm} \\ \end{array} $$ The seven two-phase equilibria in Ni-S-O and Fe-S-O are NiS/Ni3S2, Ni3S2/Ni0, NiS/NiO, NiO/NiSO4, Fe2O3/Fe2(SO4)3, Fe2O3/FeSO4, and FeSO4/Fe2(SO4)3, and the four three-phase equilibria and the one two-phase equilibrium in Fe-Ni-S-0 are sp + (Fe, Ni)S + (Fe, Ni)4S3, sp + (Fe,Ni)4S3 + (Fe, Ni)O, sp + (Fe, Ni)O + (Fe, Ni)SO4, and Fe2O3 + sp + (Fe, Ni)SO4 and sp + (Fe,Ni)S. The sp + (Fe, Ni)S two-phase equilibrium was measured by using mixtures containing a major portion of one phase and a minor portion of the other. The results are presented in terms of oxygen potential as a function of metal ratio,yNi =xNi/(xFe +xNi) at constant temperatures andPSO2 = 1 atm. The calculated stability diagrams atPSO2 = 1 atm from thermodynamic models are in agreement with experimental results. Several of the stability diagrams atPSO2 = 0.1 and 0.01 are also calculated and presented.
To Dissociate or Suppress? Predicting Automatic vs. Conscious Cognitive Avoidance

Cognitive avoidance is a common response to sexual assault and reminders of trauma, but there is a paucity of research regarding predictors of automatic and conscious cognitive avoidance in response to trauma-related stimuli. The present study examined whether posttraumatic stress disorder (PTSD) and depression symptoms, physiological responses, and subjective emotional responses predicted peritraumatic dissociation and thought suppression in a sample of 86 female sexual assault victims. Participants provided information about their current symptoms of PTSD and depression as well as their emotional reactions and physiological responses to hearing a personalized sexual assault narrative. PTSD and self-reported anger predicted thought suppression; peritraumatic dissociation was predicted by PTSD symptoms, changes in skin conductance, and self-reported arousal. Heart rate failed to predict either cognitive avoidance response. The results suggest that peritraumatic dissociation and thought suppression are ass...
Using a clinical project for teaching an understanding of the research process in the associate degree nursing curricula

Abstract The purpose of this article is to describe the implementation of a pilot project in an associate degree nursing program that uses a basic research project as the means to teach students about research concepts and the research process. By incorporating this project in the curricula, students were able to display a better understanding of nursing research findings and to enhance their utilization of evidence-based nursing practice.
Peripheral Blood Manifestations of TH2 Lymphocyte Activation in Stable Atopic Asthma and During Exercise-Induced Bronchospasm

Background Recently, T H2 lymphocyte activation has been shown to play a key role in initiating and propagating the inflammatory response in asthmatic airways. This is manifest through increased numbers of "activated" CD 25-(IL-2R)-bearing T-helper cells and can be seen through the IL-5 driven recruitment of eosinophils and IL-4 medicated B-cell expression of CD23 (low affinity IgE receptor) and ultimately IgE production. Objective To gain a better understanding of the role of immune cells in asthma by describing the peripheral blood immune cell phenotypes in mild atopic asthma. Methods We enrolled 13 patients with mild atopic asthma and a group of seven nonatopic, nonasthmatic controls. Objective measures of lung function were obtained. The peripheral blood was analyzed by flow cytometry for specific cellular markers at rest and during the development of exercise induced bronchospasm. Results At rest the number of CD23-bearing B cells (169/mL versus 117 /mL; P = .05) and the number of CD25-bearing T cells (355 /mL versus 237/mL; P = .03) were increased in the asthma group. There was linear relationship between these two lymphocyte subsets and the maximum voluntary ventilation at rest (r = 0.56, P = .01 and r=0.57, P = .01). With the development of exercise-induced bronchospasm there was a significantly greater increase in CD23-positive B cells (96.7/mL versus 59.7/mL; P = .05) and CD25-positive T cells (111.8/mL versus 45.1; P = .01) in the asthma group. Conclusions These data indicate that T H2 lymphocyte activation is manifested by increased numbers of CD23-bearing B cells and CD25-bearing T cells in the peripheral blood of patients with stable mild atopic asthma. Further, these immune cell subsets correlate with markers of resting lung function and increase in the peripheral blood early after the development of exercise-induced bronchospasm.
AKT activity regulates the ability of mTOR inhibitors to prevent angiogenesis and VEGF expression in multiple myeloma cells

We recently demonstrated that the mammalian target of rapamycin (mTOR) inhibitor, CCI-779, curtailed the growth of a subcutaneous challenge of multiple myeloma (MM) cells in immunodeficient mice. This antitumor effect was associated with prevention of cell proliferation, induction of apoptosis and inhibition of angiogenesis. Interestingly, myeloma tumors with heightened AKT activation were particularly sensitive to a CCI-779-induced antitumor response. To investigate whether part of the differential sensitivity was due to an AKT-regulated effect on angiogenesis, we compared the effects of mTOR inhibitors against isogenic MM cell lines that only differ by their degree of AKT activity. In this model, heightened AKT activity significantly sensitized MM cells to the following inhibitory effects of mTOR inhibition: angiogenesis in vivo, vascular endothelial growth factor (VEGF) expression in vitro and in vivo and VEGF translation (but not transcription). Assessment of p70S6 kinase activity indicated that rapamycin induced comparable mTOR inhibition in both cell lines suggesting that an adverse effect on VEGF cap-dependent translation would be comparable. Internal ribosome entry site (IRES)-mediated cap-independent translation is a salvage pathway for protein expression when mTOR is inhibited, so we analyzed a possible regulatory role of AKT on VEGF IRES activity. We found that elevated AKT activity inhibited VEGF IRES function. These results support a mechanism whereby AKT prevents VEGF IRES activity in myeloma cells during mTOR inhibition resulting in a more complete abrogation of VEGF translation, and ultimately, angiogenesis.
Calculation of Mean Shift for a Binary Multiplier Using 2, 3, or 4 Bits at a Time

Binary multiplication can be speeded up by taking two or more bits of the multiplier at a time. This note describes an exact method, based on the use of a discrete-time, finite-state system model, for calculating the gain in multiplication speed resulting from such a scheme. It is shown that the gain in speed is less than what had previously been obtained using an approximation formula.
DNA Replication Fidelity: Proofreading in Trans

Proofreading is the primary guardian of DNA polymerase fidelity. New work has revealed that polymerases with intrinsic proofreading activity may cooperate with non-proofreading polymerases to ensure faithful DNA replication.
Pediatric anorectal impalement with bladder rupture: case report and review of the literature

Rectal impalement involves foreign body trauma to the anus or rectum resulting in intra- or extraperitoneal rupture. Evaluation of suspected rectal impalement injury involves careful history and physical examination. Ruling out rectal perforation in patients with reported impalement is critical even if there is no evidence of trauma to the perineum. There are few reports on pediatric impalement and only 1 reported case of pediatric rectal impalement with bladder rupture. We report a rectal impalement with extraperitoneal bladder injury in a 12-year-old boy and review the literature on treatment of these injuries.
Controlling the conformation of arylamides: computational studies of intramolecular hydrogen bonds between amides and ethers or thioethers.

The role of an ortho-alkyl-thioether group in controlling the conformation around the ring-N bonds of meta-connected arylamide oligomers is studied. Density functional theory (DFT) geometries of model compounds, includingacetanilide, an ether acetanilide, and a thioether acetanilide, and their corresponding diamides, show that for either monoamide or diamide the alkyl side chain of the thioether should be perpendicular to the aryl plane, whereas for the ether mono-amide, the alkyl side chain is in the aryl plane. DFT ring-N torsional potentials and constrained geometries of the model compounds demonstrate that carbonyl-S repulsion leads to a high torsional barrier and that intramolecular N-H...S and C-H...O hydrogen bonds and ring-amide conjugation lead to N-H having a preferred orientation in the benzene plane pointing towards S. The N-H bond lengthens and the ortho-ring C-H bond shortens in a regular pattern in the approach to the preferred orientation. Calculated IR frequencies for the N-H stretch show a clear red shift between model compounds without and with the thioether side chain.
Clinical Experience in Disorders of Haemostasis

Desmopressin has found clinical application in a variety of haemostatic disorders affecting platelet function or factor VIII activity. These disorders include haemophilia A, von Willebrand’s disease (vWD), uraemia, congenital platelet dysfunction, and the haemostatic derangement caused by cardiopulmonary bypass. Desmopressin may also be useful in acquired disorders of platelet function such as those caused by antiplatelet drugs, and in hepatic cirrhosis. These disorders of haemostasis may produce excessive bleeding during minor or major surgical procedures, with accidental trauma, or spontaneously. The traditional approach has emphasised blood component therapy when excessive bleeding is apparent or likely to occur. However, transfusion therapy is not without risk. Pharmacological agents such as desmopressin that are not derived from blood products offer the potential to achieve adequate haemostasis without the risks of transfusion therapy.
Spontaneous emission in cavities: How much more classical can you get?

Cavity-induced changes in atomic spontaneous emission rates are often interpreted in terms of quantum electrodynamical zero-point field fluctuations. A completely classical method of computing this effect in terms of the unquantized normal mode structure of the cavity is presented here. Upon applying the result to a classical dipole radiating between parallel mirrors, we obtain the same cavity correction as that for atomic spontaneous emission in such a cavity. The theory is then compared with a recent experiment in the radio-frequency domain.
Interference with wound healing by the local action of adrenocortical steroids.

In our previous studies of the effects of adrenocortical secretions on the anatomy of the body, important changes were observed in fibroelastic connective tissue. Daily treatment of rats with 1 to 3 mg. of adrenocorticotropin for 21 days increased the compactness of the connective tissue fibers of the dermis (Baker, Ingle, Li and Evans, 1948). Subsequently, it was found that direct application of hog adrenal extract to the skin for 108 days caused a marked thinning of the dermis which was limited to the area of treatment (Castor and Baker, unpublished). The matrix of the dermis became more homogeneous, the collagenous fibers appearing to be fused together. Elastic fibers were spared. The fibroblasts and other cellular constituents were reduced in number. These observations combined with the demonstration that adrenocortical steroids inhibit growth of hair and epidermis by local action (Baker and Whitaker, 1948) induced us to investigate the direct effects of these hormones on the healing of wounds.
Timing of Sexual Maturation

To the Editor. — I read with interest the article of Sun et al1 on the timing of sexual maturation among US children that was based on data of the Third National Health Examination Survey (NHANES III).2 The authors estimated that the median age at onset of sexual maturation in boys, ie genital stage 2 (G2) according to Tanner classification, is 10.03 years for non-Hispanic white boys, 9.20 years for non-Hispanic black boys, and 10.29 years for Mexican American boys. In this study G2 occurs much earlier than in previous reports on the sexual maturation of US3 or European4 boys, which generally find the onset of puberty to occur at or after the age of 11 years. Furthermore, in the article the median age at G3 for non-Hispanic white boys was 12.32 years, for non-Hispanic black boys 11.78 years, and for Mexican American boys 12.53 years. These data are most astonishing because they suggest that, in 50% of the boys, the transition from G2 to G3 takes 2.2 to 2.8 years. For those practicing pediatric endocrinology it is well-known that it is unusual for an adolescent to remain in the same pubertal stage for >2 years, and in that case the subject should be investigated for possible pubertal arrest. A long transition time (1.6–2.49 years) was also reported for G4 to G5, whereas for G3 to G4 the transition time, in the ethnic groups studied, ranged from 1.2 to 1.62 years. Unfortunately, the authors did not comment on this matter in …
Solution precursor high-velocity oxy-fuel spray ceramic coatings

Abstract For the first time, the solution precursor high-velocity oxy-fuel spray process was used to deposit Al 2 O 3 –ZrO 2 ceramic coatings. X-ray diffraction analysis and transmission electron microscopy characterization show that the as-sprayed coating is composed of mixed nanocrystalline ZrO 2 and γ-Al 2 O 3 as well as amorphous phases . The as-sprayed coating consists of ultrafine splats with diameters ranging from 2 to 5 μm. Few spherical particles, hollow-shell structures are also observed on the coating surface. Polished cross-section shows that the coating is quite dense with a thickness of 40 μm.
An ideally viscoplastic analysis of the yield point phenomenon

Abstract A very crude approximation to the dependence of the velocity of mobile dislocations on applied stress is to assume that for stresses below a certain level the velocity is zero and for stresses at this level the velocity can take any required value. This first order approximation leads to a predicted material response which is that of the perfectly plastic model. In the present paper a second order approximation is examined. In particular the implications of the inclusion of an upper limit to the dislocation velocity are explored with reference to the phenomenon of the upper yield point and subsequent yield drop. An analytical expression for the upper yield stress is developed which is an upper bound to the actual upper yield stress in a material.
SUPERCONDUCTING STATE UNDER THE INFLUENCE OF EXTERNAL DYNAMIC PAIR BREAKING.

A model is developed for a superconductor under an external dynamic pair-breaking influence such as a flux of optical photons. The recombination time for quasiparticles to form pairs is much greater than the characteristic time for their thermalization to the lattice temperature $T$. For this reason the model treats the unpaired electrons as a Fermi gas at temperature $T$, but more numerous than in the complete equilibrium situation.
The influence of age on the gastrointestinal absorption of mercuric chloride and methyl mercury chloride in the rat

Abstract The intestinal absorption of mercuric chloride and methyl mercury chloride was determined in neonatal (6-day-old) and mature (7-week-old) rats. No differences between the two age groups were observed in the absorption of methyl mercury chloride (0.08 μg Hg/ml) determined up to 2 hr after administration in vivo into closed segments of the duodenum or ileum. In contrast, the 1-hr duodenal absorption of mercuric chloride (8 μg Hg/ml) was significantly greater in neonatal animals (18.1%) as compared to 23-day-old weanling (7.3%) or mature (3.6%) animals. Ileal absorption of mercuric chloride was also higher in neonates than in mature animals, but the magnitude of the difference was less than that observed in the duodenum. GI absorption of mercuric chloride (46 μg Hg/kg) was also assessed in neonatal, weanling, and mature rats at 4 and 43 hr after gastric intubation. The percentage of the dose in the carcass, determined after removal of the GI tract, was significantly higher at both times in neonatal and weanling rats as compared to mature animals. Analysis of mercury content in the gastrointestinal tract of these animals also indicated age-dependent differences in mercury transit through the GI lumen. The extent of gastric emptying of mercury by 4 hr after dosing was significantly less in neonatal and weanling rats compared to mature animals. In addition, the small intestinal transit of mercury was markedly slower in neonates with 74.8% of the dose in the GI tract after 43 hr as compared to 5.2% and 3.0% in weanling and mature animals, respectively. These findings indicate that in the neonate, exposure to inorganic mercury by the oral route can be expected to result in higher systemic, as well as small intestinal, levels of mercury because of enhanced GI absorption and decreased luminal transit, respectively.
Confusion over residency and the escalation of damselfly territorial disputes

Abstract Territorial contests among male Calopteryx maculata (Odonata) damselflies normally involve one or a few short (4–10s) pursuits of an intruder by the resident. However, in a 3-year sample of 2005 bouts, 18·5% involved escalated, spiralling aerial chases that were significantly longer, some lasting several hours. These escalations usually occurred when two males shared the same territory but were rare in contests with intruders or with neighbouring territorial males. Escalations were most probably due to situations in which two males accidentally became residents in the same territory. This removed the ‘residency’ asymmetry that appears to settle most territorial disputes in these damselflies. Using moving territories (oviposition sites), the ‘confusion over residency’ hypothesis for escalation was tested experimentally. Bouts between males on adjacent, equally sized sites were escalated significantly in duration and intensity when their territories were merged. These experiments also showed that two alternative hypotheses, the ‘male aggressiveness’ and ‘valuable resource’ hypothesis, were not important general explanations of the escalation of contests.
Identification of Information Flow-Modulating Drug Targets: A Novel Bridging Paradigm for Drug Discovery

Our objective in this study was to identify novel metrics for efficient identification of drug targets using biological network topology data. We developed a novel paradigm and metric, namely, bridging centrality, capable of identifying nodes critically involved in connecting or bridging modular subregions of a network. The topological and biological characteristics of bridging nodes were delineated in a diverse group of published yeast networks and in three human networks: those involved in cardiac arrest, C21-steroid hormone biosynthesis, and steroid biosynthesis. The bridging centrality metric was highly selective for bridging nodes. Bridging nodes differed distinctively from nodes with high degree and betweenness centrality. Bridging nodes had lower lethality, and their gene expression was consistent with independent regulation. Analysis of biological correlates indicated that bridging nodes are promising drug targets from the standpoints of efficacy and side effects. The bridging centrality method is a promising computational systems biology tool to aid target identification in drug discovery.
Generation of acoustic and gravity waves by turbulence in an isothermal stratified atmosphere

Lighthill's method of calculating the aerodynamic emission of sound waves in a homogeneous atmosphere is extended to calculate the acoustic and gravity-wave emission by turbulent motions in a stratified atmosphere. The acoustic power output is Pac ≈ 103θouo3/loM5 ergs/cm3 sec, and the upward gravity wave flux is Fzgr ≈ 102θoUo3/lo (lo ergs/cm3 sec. Here u0 is the turbulence velocity scale, l0 is its length scale, and H the scale height at the atmosphere. M = u0/c0 is the Mach number of the turbulence. The acoustic power output is proportional to the maximum value of the turbulence spectrum, and inversely to its rate of falloff at high frequencies. The stratification cuts off the acoustic emission at low Mach numbers. The gravity emission occurs near the critical angle to the vertical θc = cos−1ω/ω2, where ω22 = (γ - 1)/γ2 (c0/H), and at very short wavelengths. It is proportional to the large wave number tail of the turbulence spectrum. On the sun, gravity-wave emission is much more efficient than acoustic, but can occur only from turbulent motions in stable regions, whereas acoustic waves are produced by turbulence in the convection zone.
Use of thermal cycling to reduce adhesion of OTS coated coated MEMS cantilevers

°Microelectromechanical systems (MEMS) have enormous potential to contribute in diverse fields such as automotive, health care, aerospace, consumer products, and biotechnology, but successful commercial applications of MEMS are still small in number. Reliability of MEMS is a major impediment to the commercialization of laboratory prototypes. Due to the multitude of MEMS applications and the numerous processing and packaging steps, MEMS are exposed to a variety of environmental conditions, making the prediction of operational reliability difficult. In this paper, we investigate the effects of operating temperature on the in-use adhesive failure of electrostatically actuated MEMS microcantilevers coated with octadecyltrichlorosilane (OTS) films. The cantilevers are subjected to repeated temperature cycles and electrostatically actuated at temperatures between 25°C and 300°C in ambient air. The experimental results indicate that temperature cycling of the OTS coated cantilevers in air reduces the sticking probability of the microcantilevers. The sticking probability of OTS coated cantilevers was highest during heating, which decreased during cooling, and was lowest during reheating. Modifications to the OTS release method to increase its yield are also discussed.
On the path integral representation of stochastic processes

We derive the path integral representation of the conditional probability for a Markovian process starting from the master equation. Existing derivations require both the variable and the transition probability to be extensive. We show that this requirement may be relaxed if Langer's formula for the transition probability is used. We prove that different path integral representations appearing in the literature are in fact equivalent and correspond to various choices of an arbitrary parameter.
Estrogen increases Nrf2 activity through activation of the PI3K pathway in MCF-7 breast cancer cells

The actions of the transcription factor Nuclear factor erythroid 2-related factor (Nrf2) in breast cancer have been shown to include both pro-oncogenic and anti-oncogenic activities which is influenced, at least in part, by the hormonal environment. However, direct regulation of Nrf2 by steroid hormones (estrogen and progesterone) has received only scant attention. Nrf2 is known to be regulated by its cytosolic binding protein, Kelch-like ECH-associated protein 1 (Keap1), and by a Keap1-independent mechanism involving a series of phosphorylation steps mediated by phosphatidylinositol 3-kinase (PI3K) and glycogen synthase kinase 3 beta (GSK3β). Here, we report that estrogen (E2) increases Nrf2 activity in MCF7 breast cancer cells through activation of the PI3K/GSK3β pathway. Utilizing antioxidant response element (ARE)-containing luciferase reporter constructs as read-outs for Nrf2 activity, our data indicated that E2 increased ARE activity >14-fold and enhanced the action of the Nrf2 activators, tertiary butylhydroquinone (tBHQ) and sulforaphane (Sul) 4 to 9 fold compared with cells treated with tBHQ or Sul as single agents. This activity was shown to be an estrogen receptor-mediated phenomenon and was antagonized by progesterone. In addition to its action on the reporter constructs, mRNA and protein levels of heme oxygenase 1, an endogenous target gene of Nrf2, was markedly upregulated by E2 both alone and in combination with tBHQ. Importantly, E2-induced Nrf2 activation was completely suppressed by the PI3K inhibitors LY294002 and Wortmannin while the GSK3β inhibitor CT99021 upregulated Nrf2 activity. Confirmation that E2 was, at least partly, acting through the PI3K/GSK3β pathway was indicated by our finding that E2 increased the phosphorylation status of both GSK3β and Akt, a well-characterized downstream target of PI3K. Together, these results demonstrate a novel mechanism by which E2 can regulate Nrf2 activity in estrogen receptor-positive breast cancer cells and suggest that patients׳ hormonal status through this activity may play a significant role in some therapeutic outcomes.
Shewanella spp. genomic evolution for a cold marine lifestyle and in-situ explosive biodegradation.

Shewanella halifaxensis and Shewanella sediminis were among a few aquatic γ-proteobacteria that were psychrophiles and the first anaerobic bacteria that degraded hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). Although many mesophilic or psychrophilic strains of Shewanella and γ-proteobacteria were sequenced for their genomes, the genomic evolution pathways for temperature adaptation were poorly understood. On the other hand, the genes responsible for anaerobic RDX mineralization pathways remain unknown. To determine the unique genomic properties of bacteria responsible for both cold-adaptation and RDX degradation, the genomes of S. halifaxensis and S. sediminis were sequenced and compared with 108 other γ-proteobacteria including Shewanella that differ in temperature and Na+ requirements, as well as RDX degradation capability. Results showed that for coping with marine environments their genomes had extensively exchanged with deep sea bacterial genomes. Many genes for Na+-dependent nutrient transporters were recruited to use the high Na+ content as an energy source. For coping with low temperatures, these two strains as well as other psychrophilic strains of Shewanella and γ-proteobacteria were found to decrease their genome G+C content and proteome alanine, proline and arginine content (p-value <0.01) to increase protein structural flexibility. Compared to poorer RDX-degrading strains, S. halifaxensis and S. sediminis have more number of genes for cytochromes and other enzymes related to RDX metabolic pathways. Experimentally, one cytochrome was found induced in S. halifaxensis by RDX when the chemical was the sole terminal electron acceptor. The isolated protein degraded RDX by mono-denitration and was identified as a multiheme 52 kDa cytochrome using a proteomic approach. The present analyses provided the first insight into divergent genomic evolution of bacterial strains for adaptation to the specific cold marine conditions and to the degradation of the pollutant RDX. The present study also provided the first evidence for the involvement of a specific c-type cytochrome in anaerobic RDX metabolism.
Association of phosphatidylinositol 3-kinase, via the SH2 domains of p85, with focal adhesion kinase in polyoma middle t-transformed fibroblasts

Focal adhesion kinase (FAK), a non-receptor protein tyrosine kinase, becomes activated and phosphorylated on tyrosine in cells transformed with v-src. By cytoimmunofluorescence a sub-fraction of the p85 subunit of phosphoinositide 3-kinase (PI 3-kinase) localized in focal adhesion plaques. We examined the possibility that FAK associates with PI 3-kinase. In fibroblasts transformed with polyoma middle t, PI 3-kinase activity co-immunoprecipitated with pp125FAK using two different antibodies against this protein. PP125FAK from middle t-transformed cells associated with a glutathione-S-transferase fusion protein containing the 85-kDa subunit of phosphatidylinositol 3-kinase. Both of the SH2 domains and the SH3 domain of p85 also formed complexes with pp125FAK in vitro. Phosphopeptides that bind to the SH2 domains completely blocked the binding of full-length p85 to pp125FAK, while a peptide that binds to the SH3 domain was ineffective, indicating that the association between p85 and pp125FAK is mediated by the SH2 domains of p85.
Pore distribution in high-volatile bituminous coal: An e.p.r. study using nitroxide spin labels

Abstract Nitroxide spin labels of different size were diffused into high-volatile bituminous coal from the Mary Lee and Black Creek Coal seams of Alabama in an effort to study the relative pore size and number distributions. The nitrogen coupling in the principal z direction of the incorporated spin label exhibits a temperature dependence above 250 K that is largely a result of librational motion of the nitroxide moiety about an N-C bond. Below 250 K, the temperature dependence of the nitrogen coupling behaves in the same manner as found for spin labels in solids that exhibit a hydrogen bond equilibrium at low temperatures. The distribution of pore sizes differs considerably between the Mary Lee and Black Creek coals. Similar studies of selected coal samples from the Penn State coal sample bank indicate that the spin-label doping method proposed is not applicable to all types of coal; however, it can be used to study selected samples of high-volatile bituminous coal.
Iterative radial basis functions neural networks as metamodels of stochastic simulations of the quality of search engines in the World Wide Web

Abstract Stochastic simulation has been very effective in many domains but never applied to the WWW. This study is a premiere in using neural networks in stochastic simulation of the number of rejected Web pages per search query. The evaluation of the quality of search engines should involve not only the resulting set of Web pages but also an estimate of the rejected set of Web pages. The iterative radial basis functions (RBF) neural network developed by Meghabghab and Nasr [Iterative RBF neural networks as meta-models for stochastic simulations, in: Second International Conference on Intelligent Processing and Manufacturing of Materials, IPMM’99, Honolulu, Hawaii, 1999, pp. 729–734] was adapted to the actual evaluation of the number of rejected Web pages on four search engines, i.e., Yahoo, Alta Vista, Google, and Northern Light. Nine input variables were selected for the simulation: (1) precision, (2) overlap, (3) response time, (4) coverage, (5) update frequency, (6) boolean logic, (7) truncation, (8) word and multi-word searching, (9) portion of the Web pages indexed. Typical stochastic simulation meta-modeling uses regression models in response surface methods. RBF becomes a natural target for such an attempt because they use a family of surfaces each of which naturally divides an input space into two regions X + and X − and the n patterns for testing will be assigned either class X + or X −. This technique divides the resulting set of responses to a query into accepted and rejected Web pages. To test the hypothesis that the evaluation of any search engine query should involve an estimate of the number of rejected Web pages as part of the evaluation, RBF meta-model was trained on 937 examples from a set of 9000 different simulation runs on the nine different input variables. Results show that two of the variables can be eliminated which include: response time and portion of the Web indexed without affecting evaluation results. Results show that the number of rejected Web pages for a specific set of search queries on these four engines very high. Also a goodness measure of a search engine for a given set of queries can be designed which is a function of the coverage of the search engine and the normalized age of a new document in result set for the query. This study concludes that unless search engine designers address the issue of rejected Web pages, indexing, and crawling, the usage of the Web as a research tool for academic and educational purposes will stay hindered.
Giant discrete steps in metal-insulator transition in perovskite manganite wires.

Optical lithography is used to fabricate LPCMO wires starting from a single La5=80:3Pr0:3Ca3=8MnO3 (LPCMO) film epitaxially grown on a LaAlO3100 substrate. As the width of the wires is decreased, the resistivity of the LPCMO wires exhibits giant and ultrasharp steps upon varying temperature and magnetic field in the vicinity of the metal-insulator transition. The origin of the ultrasharp transitions is attributed to the effect of spatial confinement on the percolative transport in manganites. The strong spin-charge-lattice interaction in transition metal oxides (TMOs) often leads to a striking phenomenon called electronic phase separation (PS), which is identified with the coexistence of a range of exotic electronic and magnetic phases despite the single crystalline structure [1]. The role of the PS in the related physical properties such as high-T c superconducting and colossal magnetoresistance (CMR) is a hotly debated issue in the field of condensed matter physics. Spatial confinement is a very useful route to gain deeper insight into the nature of PS. In particular, when the spatial dimension of the TMOs is reduced to the characteristic PS length scale, one would expect that changes in the transport properties of the TMOs could be quite dramatic. A model system for this study is La5=8xPrxCa3=8MnO3 (LPCMO), a perovskite manganite that is famously known for its large-scale PS. Transmission electron microscopy has revealed submicrometer-scaled ferromagnetic (FM) and charge ordered (CO) domains [2]. The coexistence of FM=CO phases in LPCMO reflects the competition between the intrinsic properties of its two starting materials, i.e., FM La5=8Ca3=8MnO3 (TC 275 K) and CO antiferro
Notes from the underground: Highlights from plant-microbe interactions

Basic research on communication between plants and microorganisms has revealed that symbiotic and pathogenic microorganisms have developed a diverse array of mechanisms to exploit their host plants. The interaction strategies of symbiotic Rhizobia, pathogenic Pseudomonads and the natural genetic engineer Agrobacterium are particularly revealing. The lessons learned from these organisms demonstrate that understanding their life style is essential for engineering improved crop plants in the next century.
AIDS knowledge, attitudes and behaviors among deaf college students: A preliminary study

Due to the dearth of knowledge in the literature related to any aspect of AIDS in the deaf community, a sample (N=84) of deaf undergraduate students at Gallaudet University was surveyed in order to determine levels of AIDS knowledge, AIDS-related attitudes and sexual behavior patterns among the sample. Results indicate that the students in the sample have relatively high levels of general knowledge about AIDS. However, the high levels of AIDS knowledge-and a reported moderate degree of comfort in discussing safe sex issues with sexual partners—among this sample do not correlate with less risky sexual behaviors. Results indicate that many of the students may be placing themselves at risk for AIDS and other sexually-transmitted diseases. Implications of the study for social workers and other practitioners are presented and suggestions for future research are offered.
Are women really more talkative than men

Women are generally assumed to be more talkative than men. Data were analyzed from 396 participants who wore a voice recorder that sampled ambient sounds for several days. Participants' daily word use was extrapolated from the number of recorded words. Women and men both spoke about 16,000 words per day.
On circuits through five edges

Abstract Let L be a set of five independent edges in a 5-connected graph G . This paper proves that G has a circuit containing the edges of L if and only if G - L is connected. This is a specific case of a conjecture of Lovasz and Woodall.