bluuebunny/crossref_metadata_2025 huggingface dataset:
Decolorization of a reactive dye solution and treatment of a textile wastewater by electrocoagulation and chemical coagulation: Techno‐economic comparison
Authors: Yuksel Ebubekir , Gurbulak Ercan , Eyvaz Murat
Published: July 2011

In this study, the effects of operational parameters such as initial pH, current density, electrolysis time, and initial dye concentrations on the decolorization of Reactive Yellow 135 (RY 135) solutions and the treatment of a textile wastewater by electrocoagulation (EC) with aluminum electrodes were investigated separately. Total organic carbon (TOC) and dye removal ratios were used to measure the treatment efficiency. Energy and electrode consumptions were calculated per m3 of dye solution and per kg of pollutant removed. Amount of sludge produced after EC was also reported per m3 of dye solution. For a complete technical analysis, chemical coagulation experiments with aluminum salts were also carried out. Different direct and indirect cost items including energy, sacrificial electrodes, labor, sludge handling and disposal, maintenance, and depreciation costs have been considered in the calculation of the total operating cost. Under the optimum parameters found in this study, 0.23 $/m3 of total operating cost was acquired with 81% of COD, 85% of TOC, 93.7% of turbidity, and 97.1% of TSS removal efficiencies in treatment of the textile wastewater with EC. 0.11 kWh/m3 of energy and 0.03 kg/m3 of aluminum were consumed while 0.15 kg/m3 of sludge were produced in the process. © 2011 American Institute of Chemical Engineers Environ Prog, 2011
Biosorption of 2,4‐d, 2,4‐DP, and 2,4‐DB from aqueous solution by using thermophilic anoxybacillus flavithermus and analysis by high‐performance thin layer chromatography: Equilibrium and kinetic studies
Authors: Ozdemir Sadin , Bekler Fatma Matpan , Okumus Veysi , Dundar Abdurrahman , Kilinc Ersin
Published: July 2011

In this study, the potential biosorption characteristics of the thermophilic Anoxybacillus flavithermus (A. flavithermus) was investigated for the removal of the chlorophenoxy acid derivates, namely, 2,4‐dichlorophenoxy acetic acid (2,4‐D), 2,4‐dichlorophenoxy propanoic acid (2,4‐DP or dichlorprop), and 2,4‐dichlorophenoxy butyric acid (2,4‐DB). The experiments were performed for the simultaneous biosorption of the studied pesticides. Optimum biosorption conditions were determined as a function of contact time, pH of the solution, amount of biomass, and initial pesticides concentrations. The concentrations of the pesticides in the remaining solutions were simultaneously analyzed by high performance thin layer chromatography. The optimum parameters were found as pH: 4.0 for biosorption medium, 60 min of contact time, 50 mg of bacteria, and 50 mg L−1 of initial pesticides concentrations. Langmuir and Freundlich models were applied to describe the biosorption isotherm of the pesticides by A. flavithermus as biomass. Biosorption of pesticides on to A. flavithermus showed pseudo first‐order rate kinetics at different initial concentration of pesticides and different temperatures. The experimental adsorption data were fitted both the Langmuir and Freundlich adsorption models. Fourier‐transform Infrared spectroscopy was used to understand the bonding mechanism of pesticides to biosorbent and surface functionality of the biosorbent The highest pesticide uptake was calculated from Langmuir isotherm and found to be 24.15 mg g−1 for 2,4‐D. Among the studied pesticides, 2,4‐DP showed difference adsorption behavior. According to in your comments the reason of this that 2,4‐DP contain an asymmetric carbon atom, which provide a molecular chirality. © 2011 American Institute of Chemical Engineers Environ Prog, 2011
Bedform response to flow variability
Authors: Nelson J. M. , Logan B. L. , Kinzel P. J. , Shimizu Y. , Giri S. , Shreve R. L. , McLean S. R.
Published: July 2011

Laboratory observations and computational results for the response of bedform fields to rapid variations in discharge are compared and discussed. The simple case considered here begins with a relatively low discharge over a flat bed on which bedforms are initiated, followed by a short high‐flow period with double the original discharge, during which the morphology of the bedforms adjusts, followed in turn by a relatively long period of the original low discharge. For the grain size and hydraulic conditions selected, the Froude number remains subcritical during the experiment, and sediment moves predominantly as bedload. Observations show rapid development of quasi‐two‐dimensional bedforms during the initial period of low flow with increasing wavelength and height over the initial low‐flow period. When the flow increases, the bedforms rapidly increase in wavelength and height, as expected from other empirical results. When the flow decreases back to the original discharge, the height of the bedforms quickly decreases in response, but the wavelength decreases much more slowly. Computational results using an unsteady two‐dimensional flow model coupled to a disequilibrium bedload transport model for the same conditions simulate the formation and initial growth of the bedforms fairly accurately and also predict an increase in dimensions during the high‐flow period. However, the computational model predicts a much slower rate of wavelength increase, and also performs less accurately during the final low‐flow period, where the wavelength remains essentially constant, rather than decreasing. In addition, the numerical results show less variability in bedform wavelength and height than the measured values; the bedform shape is also somewhat different. Based on observations, these discrepancies may result from the simplified model for sediment particle step lengths used in the computational approach. Experiments show that the particle step length varies spatially and temporally over the bedforms during the evolution process. Assuming a constant value for the step length neglects the role of flow alterations in the bedload sediment‐transport process, which appears to result in predicted bedform wavelength changes smaller than those observed. However, observations also suggest that three‐dimensional effects play at least some role in the decrease of bedform wavelength, so incorporating better models for particle hop lengths alone may not be sufficient to improve model predictions. Published in 2011. This article is a US Government work and is in the public domain in the USA.
Isolation and characterization of an environmental cadmium- and tellurite-resistant Pseudomonas strain
Authors: Chien Chih-Ching , Jiang Ming-Hui , Tsai Meng-Ru , Chien Chih-Ching
Published: July 2011

A Pseudomonas strain (TeU), resistant to tellurite (TeO 32−) and cadmium (Cd2+) ions, was isolated from heavy-metal–contaminated sediments by enrichment. Black precipitates, presumably the product of the reduction of tellurite, such as tellurium, occurred in cultures of the isolate after growth in medium containing tellurite. Quantitative determination of the TeO 32− concentration in the liquid culture demonstrated a decreased concentration of tellurite (to less than 100 µM) from initial concentrations of approximately 1,000 µM within 24 h of growth. Strain TeU was resistant to TeO 32− and Cd2+ concentrations as high as 2,000 µM and 500 µM, respectively. Transposon mutagenesis of strain TeU resulted in mutants exhibiting Cd2+ sensitivity (Strain BU21) and one with decreased ability to reduce tellurite (strain AU08). Strain BU21 was less tolerant to Cd2+ (100 µM) compared with the wild-type strain TeU (500 µM) but was still able to reduce tellurite to 80% of that of strain TeU. Although strain AU08 possesses the ability for Cd2+ resistance, it reduced less than 20% of the initial concentrations of tellurite compared with strain TeU. Genes encoding an HflKC complex and a putative metallopeptidase were associated with the bacterium's capacity for tellurite reduction and Cd resistance, respectively. The ability to reduce tellurite therefore may not be necessary for this bacterium's heavy metal and metalloid tellurite resisting ability. Environ. Toxicol. Chem. 2011;30:2202–2207. © 2011 SETAC
Vapor pressure of solid polybrominated diphenyl ethers determined via Knudsen effusion method
Authors: Fu Jinxia , Suuberg Eric M
Published: July 2011

Polybrominated diphenyl ethers (PBDEs) are flame retardants used in a variety of consumer products. The solid vapor pressures of BDE 15 and BDE 209 were determined by using the Knudsen effusion method, and the values measured extrapolated to 298.15 K are 3.12 × 10−3 and 9.02 × 10−13 Pa, respectively. The enthalpies of sublimation for these compounds have also been estimated by using the Clausius-Clapeyron equation and are 102.0 ± 3.5 and 157.1 ± 3.5 kJ/mol, respectively. In addition, the melting points and enthalpies of fusion were measured by differential scanning calorimetry. Environ. Toxicol. Chem. 2011;30:2216–2219. © 2011 SETAC
Provably stable and time‐accurate extensions of Runge–Kutta schemes for CFD computations on moving grids
Authors: Brogniez Sebastien , Rajasekharan Ajaykumar , Farhat Charbel
Published: July 2011

Extending fixed‐grid time integration schemes for unsteady CFD applications to moving grids, while formally preserving their numerical stability and time accuracy properties, is a nontrivial task. A general computational framework for constructing stability‐preserving ALE extensions of Eulerian multistep time integration schemes can be found in the literature. A complementary framework for designing accuracy‐preserving ALE extensions of such schemes is also available. However, the application of neither of these two computational frameworks to a multistage method such as a Runge–Kutta (RK) scheme is straightforward. Yet, the RK methods are an important family of explicit and implicit schemes for the approximation of solutions of ordinary differential equations in general and a popular one in CFD applications. This paper presents a methodology for filling this gap. It also applies it to the design of ALE extensions of fixed‐grid explicit and implicit second‐order time‐accurate RK (RK2) methods. To this end, it presents the discrete geometric conservation law associated with ALE RK2 schemes and a method for enforcing it. It also proves, in the context of the nonlinear scalar conservation law, that satisfying this discrete geometric conservation law is a necessary and sufficient condition for a proposed ALE extension of an RK2 scheme to preserve on moving grids the nonlinear stability properties of its fixed‐grid counterpart. All theoretical findings reported in this paper are illustrated with the ALE solution of inviscid and viscous unsteady, nonlinear flow problems associated with vibrations of the AGARD Wing 445.6. Copyright © 2011 John Wiley & Sons, Ltd.
A monotone finite volume scheme for advection–diffusion equations on distorted meshes
Authors: Wang Shuai , Yuan Guangwei , Li Yonghai , Sheng Zhiqiang
Published: July 2011

A new monotone finite volume method with second‐order accuracy is presented for the steady‐state advection–diffusion equation. The method uses a nonlinear approximation for both diffusive and advective fluxes that guarantee the positivity of the numerical solution. The approximation of the diffusive flux is based on nonlinear two‐point approximation, and the approximation of the advective flux is based on the second‐order upwind method with proper slope limiter. The second‐order convergence rate for concentration and the monotonicity of the nonlinear finite volume method are verified with numerical experiments. Copyright © 2011 John Wiley & Sons, Ltd.
Large eddy simulation using a dynamic mixing length subgrid‐scale model
Authors: Zhaolin Gu , Jianying Jiao , Yunwei Zhang , Junwei Su
Published: July 2011

A novel dynamic mixing length (DML) subgrid‐scale model for large eddy simulations is proposed in this work to improve the cutoff length of the Smagorinsky model. The characteristic mixing length (or the characteristic wave number) is dynamically estimated for the subgrid‐scale fluctuation of turbulence by the cutoff wave‐number, kc, and the dissipation wave‐number, kd. The dissipation wave number is derived from the kinetic energy spectrum equation and the dissipation spectrum equation. To prove the promise of the DML model, this model is used to simulate the lid‐driven cubical cavity with max‐velocity‐based Reynolds numbers 8850 and 12,000, the channel flows with friction‐velocity‐based Reynolds numbers 180, 395, 590, and 950, and the turbulent flow past a square cylinder at the higher Reynolds number 21,400, respectively, compared with the Smagorinsky model and Germano et al.'s dynamic Smagorinsky model. Different numerical experiments with different Reynolds numbers show that the DML model can be used in simulations of flows with a wide range of Reynolds numbers without the occurrence of singular values. The DML model can alleviate the dissipation of the Smagorinsky model without the loss of its robustness. The DML model shows some advantages over Germano et al.'s dynamic Smagorinsky model in its high stability and simplicity of calculation because the coefficient of the DML model always stays positive. The characteristic mixing length in the DML model reflects the subgrid‐scale fluctuation of turbulence in nature and thus the characteristic mixing length has a spatial and temporal distribution in turbulent flow. Copyright © 2011 John Wiley & Sons, Ltd.
Electrowetting of Molten Carbonate Electrolytes
Authors: Hsieh P. H. , Selman J. R.
Published: July 2011

The wetting characteristics of various molten carbonate electrolytes were experimentally measured and the dependence of the contact angle on polarisation was thoroughly examined for various temperatures and gas atmospheres. At open circuit under an atmosphere of CO2 and/or oxidant gases, addition of alkaline earth carbonates decreases the wettability of the electrolyte. Addition of alkaline earth carbonates also tends to decrease the temperature dependence of the contact angle. Upon polarisation, the contact angle shows a complex behaviour. In an oxidising atmosphere its dependence on potential is roughly symmetric (like an electrocapillary curve) but in a reducing atmosphere this is not the case. Generally, the contact angle increases upon cathodic polarisation but decreases in the anodic direction. These changes in contact angle are interpreted in terms of interfacial tensions. The complex dependence of contact angle on polarisation can be interpreted in terms of a superimposed electrocapillary and transport effects. As such, it may be affected by specifically adsorbed species at the electrode surface (especially complex oxides), by the basicity (oxide ion activity) of the melt, and by the potential‐induced segregation of the cationic species in the carbonate melt.
Prednisolone in Hbsag–Positive Chronic Active Hepatitis: Histologic Evaluation in A Controlled Prospective Study
Authors: Wu Pui C. , Lai Ching L. , Lam Kui C. , Ho Joana
Published: July 2011

To study the value of corticosteroids in HBsAg–positive chronic active hepatitis, 18 pairs of liver histology comprising 36 liver biopsies from a prospective, randomized, controlled trial were evaluated. The median interval between the initial and follow–up histology was 8 1/2 months in 8 patients given prednisolone and 8 1/4 months in 10 patients given placebo tablets. Following medication, there was significantly greater erosion of the limiting plate in the prenisolone group (p = 0.039) accompanied by a larger quantity of HBsAg (p = 0.045) and HBcAg (p = 0.006) in the liver. We conclude that prednisolone causes immunosuppression permitting enhanced viral multiplication and leads to increased erosion of the limiting plate. Our result also indicates that progression to cirrhosis is unhalted by prednisolone therapy. The histologic findings support clinico–biochemical conclusion that the use of prednisolone is deleterious to patients with HBsAg–positive chronic active hepatitis.
Ursodeoxycholic Acid Vs. Chenodeoxycholic Acid As Cholesterol Gallstone–Dissolving Agents: A Comparative Randomized Study
Authors: Roda Enrico , Bazzoli Franco , Morselli Labate Antonio M. , Mazzella Giuseppe , Roda Aldo , Sama Claudia , Festi Davide , Aldini Rita , Taroni Francesco , Barbara Luigi
Published: July 2011

Cholesterol gallstones are dissolved in man by chenodeoxycholic acid (CDCA) and ursodeoxycholic acid (UDCA). To test the comparative efficacy of these two cholelitholytic bile acids, 223 gallstone patients were randomly treated with either UDCA or CDCA at two different doses: 7 to 8 mg per kg per day and 14 to 15 mg per kg per day. Efficacy and factors influencing dissolution (dose, size of the stones, and time) were evaluated after 3, 6, and 12 months of treatment. UDCA was significantly more efficacious than was CDCA after 3 and 6 months of treatment, whereas after 12 months, no significant differences were observed. UDCA was equally effective at high and low doses, both on small and large stones. CDCA was significantly more effective at high doses and on small stones. Seventy–four per cent of the total dissolutions with UDCA and 42% with CDCA occurred within the first 6 months of treatment. Diarrhea and hypertransaminasemia occurred only in the CDCA–treated patients. We conclude that UDCA seems to be the bile acid of choice in dissolving cholesterol gallstones.
Kinetics of 64Copper in Primary Biliary Cirrhosis
Authors: Janssens Roelof A. , Van Den Hamer Cornelis J.A.
Published: July 2011

To assess the pathogenetic mechanisms involved in the accumulation of copper in primary biliary cirrhosis (PBC), the kinetics of 64Copper (64Cu) were studied in 6 healthy volunteers, 3 patients with PBC (Stages I to III) and a normal liver copper, and 7 patients with PBC (Stages II to IV) and a high liver copper. The kinetics of oral and i.v. administered 64Cu in patients with a normal liver copper were similar to those in controls. In patients with a high liver copper, the initial disappearance rate from the plasma of i.v. administered 64Cu was more rapid, the disappearance rate from the liver of 64Cu taken up by this organ was slower, and the fecal excretion of 64Cu less as compared with the two other groups of subjects. In addition, the fecal excretion of orally administered 64Cu was less in these patients. Computation of the rate of absorption of orally administered 64Cu revealed no differences between the three groups. Two of the patients with a high liver copper were decopperized by treatment with D–penicillamine. In these patients, the disappearance rate of i.v. administered 64Cu from the liver and the secondary reappearance rate of 64Cu into plasma became normal; however, the fecal excretion of 64Cu remained low. It is concluded that there is no pathognomonic alteration of copper metabolism in PBC, but that in some patients, copper accumulates in the liver due to decreased biliary excretion and increased clearance from the plasma, and that dilution of the tracer dose a large amount of stable copper is responsible for all abnormalities of 64Cu kinetics encountered in PBC, except low fecal excretion, which is caused by impairment of biliary excretion.
Studies to Elucidate the Thyroid Hormone Dependence of Morris Hepatoma 44
Authors: Pollack Raphael , Mishkin Shaindel Y. , Morris Harold P. , Yalovsky Mordechai A. , Mishkin Seymour
Published: July 2011

The objective of these studies was to elucidate further the mechanisms of the thyroid dependency of Morris Hepatoma 44. In vivo experiments indicated that while exogenous thyroxine (8 μg per kg) reversed the hypothyroid–mediated inhibition of primary hepatoma growth, no such effect was noted with the administration of ovine prolactin (100 μg per kg s.c.) and bovine growth hormone (100 μg per kg, s.c). In contrast, ovine prolactin significantly stimulated tumor growth in euthyroid animals. We have documented the presence of nuclear triiodothyronine (T3) receptors in Morris Hepatoma 44. The dissociation constant Kd (4.38 ± 0.84 nM) and binding capacity (2.16 ± 0.84 pmoles per mg DNA) of these receptors was significantly greater than those of host liver tissue (1.48 ± 0.41 nM and 0.93 ± 0.32 pmole per mg DNA, respectively). The binding capacity of hepatoma nuclear T3 receptors was markedly reduced in the hypothyroid state, while liver nuclear receptor capacity was not significantly changed. In addition, the binding of T3 to cytoplasmic proteins was greater in hepatomas relative to host liver. Analogous to the observations with nuclear receptors, the binding of T3 to hepatoma cytosol was significantly reduced in the hypothyroid state, while the binding activity of liver cytosol was unchanged. These results are consistent with a possible role for nuclear receptors and/or cytoplasmic binding proteins for T3 in mediating the direct influence of thyroid hormones on the growth of Morris Hepatoma 44. Our results, however, do not preclude a role for other hormones (i.e., pituitary hormones acting via the hypothalamo–hypophyseal axis) as modulators of Morris Hepatoma 44 growth.
Changes of the Golgi Apparatus Induced by Diethylmaleate in Rat Hepatocytes
Authors: Jezequel Anne-Marie , Bonazzi Patrizia , Amabili Piera , Venturini Cinzia , Orlandi Francesco
Published: July 2011

Ultrastructural studies of the liver of rats given diethylmaleate (DEM) (0.7 ml per kg body, i.p.) weight revealed marked alterations of the configuration of the Golgi complex in all hepatocytes. This consisted in dilatation of the cisternae leading to the formation of large cysts. The alteration was more prominent 15 min after administration of the drug, coincident with a 2–fold increase of bile flow and a decrease of hepatic glutathione to 15% of controls. The morphology returned to normal at 45 min after DEM administration together with a return of bile flow to control values whereas hepatic glutathione level remained markedly depressed for 2 hr, rising slowly afterwards. No other signs of altered hepatic morphology developed up to 5 hr. The morphological changes correlated with altered bile flow induced by DEM, suggesting involvement of the Golgi complex in biliary excretion of osmotically active glutathione conjugates of DEM.
A Morphological Study of the Liver and Gallbladder in Hemolysis–Induced Gallstone Disease in Mice
Authors: Trotman Bruce W. , Bongiovanni Michael B. , Kahn Marc J. , Bernstein Seldon E.
Published: July 2011

The nb/nb mouse with a hereditary hemolytic anemia is an animal model of hemolysis–induced gallstone disease. These anemic mice have hepatomegaly and form calcium bilirubinate gallstones. We undertook this study to: (a) examine the histopathology of the liver and gallbladder in nb/nb mice and (b) assess the influence of hemolysis per se on liver and gallbladder histology by transplanting nb/nb bone marrow into another genotype W/W

v
. Livers and gallbladders obtained from male nb/nb and control mice of similar age were stained with hematoxylin and eosin. Gallbladders were also stained with alcian blue (pH 2) and periodic acid–Schiff for acidic and neutral glycoproteins, respectively. Volume densities of the extralobular (blood vessels) and lobular (hepatocytic and sinusoidal) components of the liver and glands of the gallbladder neck were determined by standard morphometric techniques. The liver mass of nb/nb mice was 25% greater than that of control mice (1.79 ± 0.26 S.D. gm vs. 1.43 ± 0.23, p < 0.001). The actual hepatocytic mass of nb/nb and control mice was similar (1.35 ± 0.19 gm vs. 1.26 ± 0.21, p > 0.05). However, the sinusoidal compartment, representing extramedullary hematopoiesis, was three times greater in nb/nb than in control livers (0.40 ± 0.13 gm vs. 0.13 ± 0.05, p < 0.001). Overall, glandular concretions within the gallbladders were present at least twice as often in nb/nb than in control mice (p < 0.02). Bile pigment concretions occurred in only nb/nb gallbladders and were present three times more frequently in those with luminal gallstones (81%) than in those without stones (25%) (p < 0.02). The glandular density of nb/nb gallbladders was higher than that of control gallbladders (16 ± 21%, p < 0.02), and nb/nb gallbladders with luminal gallstones had a higher glandular density than nb/nb gallbladders without stones (88 ± 8% vs. 37 ± 20%, p < 0.05). Eight months after transplantation, recipient W/W

v
mice had not developed gallstones but had marked hepatomegaly with a disproportionate increase in the sinusoidal compartment (27.4 ± 4.9%) compared with control W/W

v
mice (9.90 ± 2.0%, p < 0.001). The glandular concretions and density in transplanted and control W/W

v
gallbladders were similar. These data indicate that: (a) the hepatomegaly of nb/nb mice is due to extramedullary hematopoiesis while the morphological mass of hepatocytes is similar in control and nb/nb mice; (b) bile pigment concretions within nb/nb gallbladders precede luminal calcium bilirubinate stone formation; (c) glandular hyperplasia is a secondary event in hemolysis–induced gallstone disease, and (d) the hemolytic anemia is responsible for the hepatomegaly and gallstone formation, but the genotype determines the glandular density and concretions within the gallbladder prior to luminal gallstone formation.
Pigment Gallstone Disease: Summary of the National Institutes of Health—International Workshop
Authors: Trotman Bruce W. , Soloway Roger D.
Published: July 2011

This report summarizes the proceedings of the first National Institutes of Health—International Workshop on Pigment Gallstone Disease. The meeting held at the University of Pennsylvania in May, 1981 consisted of eight sessions in which the following aspects of pigment gallstone disease were discussed: (a) classification; (b) epidemiology; (c) radiographic assessment; (d) gallstone composition; (e) composition of bile; (f) pathogenesis; (g) animal models, genetics, and computer analysis, and (h) medical treatment. The interaction of participants interested in various aspects of pigment stone disease was stimulating. This workshop should be a major stimulus for future studies in this relatively neglected, but important area of biliary tract lithiasis.
Chiral Cooperativity in Helical Polymers
Authors: Jain Vipul , Cheon Kap‐Soo , Tang Kai , Jha Salil , Green Mark M.
Published: July 2011

Human experience informs us of the two extreme consequences of crowding: random behavior of the individuals, in which each takes a singular path; and cooperative behavior, in which the individuals in the crowd act in a predictable uniform manner, such as in a military organization These extremes find parallels in the crowded situations encountered at the molecular level, exemplified for the former by glassy states, such as often encountered in polymeric materials,1 or for the latter, in the uniform archetypal arrangements of crystals or liquid crystals. Here we review the cooperative characteristics of uniform arrangements that take a chiral form and explore how these characteristics lead to left‐ and right‐handedness. These studies lead us to understand the basis of amplification of chirality in regular arrays, in which small influences have large consequences, and how chiral cooperativity acts in the resolution of conflict between influences favoring left‐ and right‐handedness.2
Supramolecular Capsules Derived from Calixpyrrole Scaffolds
Authors: Ballester Pablo
Published: July 2011

This review article describes recent results obtained in the self‐assembly of supramolecular capsules derived from calixpyrrole components. Due to their ease of synthesis, calix[4]pyrroles are by far the most typically used units in these systems. A clear conformational and structural analogy exists between calix[4]arenes and calix[4]pyrroles. However, to date, the number of examples in the literature that use calix[4]pyrrole scaffolds instead of calix[4]arenes for the construction of supramolecular capsules is still meager. Four different approaches are considered for the use of calix[4]pyrrole derivatives in the assembly of molecular capsules. Firstly, in an analogous manner to resorcin[4]arenes and pyrogallol[4]arenes, aryl‐extended calix[4]pyrroles with hydroxyl groups in their upper rim self‐assemble through direct or mediated rim‐to‐rim interactions into capsular aggregates. Secondly, aryl‐extended calix[4]pyrroles having non‐complementary hydrogen‐bonding groups in their upper rim form dimeric templated capsules with suitable substrates. Thirdly, the elaboration of the upper rim of the calix[4]pyrroles with urea groups affords dimeric capsules with polar functionalized interiors that closely resemble their tetraurea calix[4]arene analogs. Finally, the chemical modification of the pyrrole units of octamethyl calix[4]pyrrole into tetrathiafulvalene derivatives yields dimeric capsules induced by anion coordination that display interesting properties in the binding of electron‐poor guests.
Vascular targeting of antithrombotic agents
Authors: Carnemolla Ronald , Muzykantov Vladimir R.
Published: July 2011

In this review we discuss the limited efficacy for current pharmacological agents used in prophylaxis and treatment of thrombosis and highlight targeted delivery of anti‐thrombotic agents to fibrin, platelets, red blood cells and endothelium. © 2011 IUBMB IUBMB Life, 2011
Targeted siRNA delivery to diseased microvascular endothelial cells—Cellular and molecular concepts
Authors: Kowalski Piotr S. , Leus Niek G. J. , Scherphof Gerrit L. , Ruiters Marcel H. J. , Kamps Jan A. A. M. , Molema Grietje
Published: July 2011

Increased insight in the role of endothelial cells in the pathophysiology of cancer, inflammatory and cardiovascular diseases, has drawn great interest in pharmacological interventions aiming at the endothelium in diseased sites. Their location in the body makes them suitable targets for therapeutic approaches based on targeted drug delivery. Functional heterogeneity of the microvascular bed in normal organ homeostasis has been appreciated for a long time, and more recent studies have revealed heterogeneity in endothelial reactivity to inflammatory stimuli as well. Upon stimulation, each organ displays a vascular bed specific pattern of cell adhesion molecules providing challenging opportunities to deliver drugs or small RNAs to organ specific (micro)vascular endothelial subsets. In this review we introduce general concepts of endothelial heterogeneity in relation to disease state and its consequences for targeted therapeutic interventions. Furthermore, we will describe novel approaches to interfere with endothelial cell engagement in disease with a main focus on siRNA therapeutics and currently used nonviral lipid and polymer‐based siRNA delivery systems. The last part of this review addresses some technical issues that are essential in proving the concept of target mRNA knock down in a vascular bed specific manner, and the further development of effective endothelial cell specific drug delivery devices. © 2011 IUBMB IUBMB Life, 2011
Innovation and competition: An unstable relationship
Authors: Correa Juan A.
Published: July 2011

This paper analyzes how the establishment of the United States Court of Appeals for the Federal Circuit in 1982 has affected the relationship between innovation and competition. Using the same dataset as Aghion et al. (Competition and innovation: an inverted‐u relationship. Quarterly Journal of Economics 2005; 120(2):701–728) I find a structural break in the early 1980s. Taking this break into consideration, the inverted‐U empirical relationship between innovation and competition found by Aghion et al. does not hold. In fact, I find that there is a positive innovation–competition relationship during the period 1973–1982 and no relationship at all in the 1983–1994 period. Copyright © 2011 John Wiley & Sons, Ltd.
Effects of SiO2 nanoparticles on HFL‐I activating ROS‐mediated apoptosis via p53 pathway
Authors: Xu Zhengli , Chou Laisheng , Sun Jiao
Published: July 2011

Silicon dioxide nanoparticles (SiO2 NPs) have attracted increasing interest as nanovehicles for delivering drugs, genes and bio‐active molecules into cells. However, it is still unknown whether SiO2 NPs could cause side‐effects to normal cells. In the present study, human lung fibroblasts (HFL‐Is) were directly exposed to two different sizes of SiO2 NPs. The effect of size and concentration on cell response was studied by analyzing the cell viability, the ratio of apoptosis and the pathway of cell injury. The results demonstrated that a size‐associated and a dose‐dependent toxicity of HFL‐Is was induced by SiO2 NPs. Meanwhile, the expression of reactive oxygen species in HFL‐I was significantly increased. This activation effect was accompanied by upregulation of p53 expression, release of cytochrome C from chondriosomes, inhibition of Bcl2, and activation of Bax and caspase 9. These findings implied that SiO2 NPs might induce apoptosis of HFL‐Is by stimulating reactive oxygen species release and subsequently causing the activation of p53 pathway in vitro. Copyright © 2011 John Wiley & Sons, Ltd.
A simple cryo‐holder facilitates specimen observation under a conventional scanning electron microscope
Authors: Tang Chih‐Yuan , Huang Rong‐Nan , Kuo‐Huang Ling‐Long , Kuo Tai‐Chih , Yang Ya‐Yun , Lin Ching‐Yeh , Jane Wann‐Neng , Chen Shiang‐Jiuun
Published: July 2011

A pre‐cryogenic holder (cryo‐holder) facilitating cryo‐specimen observation under a conventional scanning electron microscope (SEM) is described. This cryo‐holder includes a specimen‐holding unit (the stub) and a cryogenic energy‐storing unit (a composite of three cylinders assembled with a screw). After cooling, the cryo‐holder can continue supplying cryogenic energy to extend the observation time for the specimen in a conventional SEM. Moreover, the cryogenic energy‐storing unit could retain appropriate liquid nitrogen that can evaporate to prevent frost deposition on the surface of the specimen. This device is proved feasible for various tissues and cells, and can be applied to the fields of both biology and material science. We have employed this novel cryo‐holder for observation of yeast cells, trichome, and epidermal cells in the leaf of Arabidopsis thaliana, compound eyes of insects, red blood cells, filiform papillae on the surface of rat tongue, agar medium, water molecules, penicillium, etc. All results suggested that the newly designed cryo‐holder is applicable for cryo‐specimen observation under a conventional SEM without cooling system. Most importantly, the design of this cryo‐holder is simple and easy to operate and could adapt a conventional SEM to a plain type cryo‐SEM affordable for most laboratories. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc.
In‐situ observation and relocation method of nanomaterial samples based on microscope systems
Authors: Zeng Leyong , Wu Aiguo , Wang Yazhuo , Pu Shiliu , Ding Jiandong
Published: July 2011

Taking poly(lactic acid) microbubbles and purple membranes as examples, a general in situ observation and relocation method of nanomaterial samples based on microscope systems was reported. First, a four‐grade coordinate with different precisions was marked around a substrate by UV lithography. Second, using optical microscope and scanning probe microscope, special positions of poly(lactic acid) microbubbles and purple membranes were observed, respectively. Third, the four‐grade coordinate value corresponded to the special sample position, and the distance between the special position and coordinate edge were recorded, respectively. Finally, the special position can be easily found again, or the sample in the special position can be manipulated and secondary processed based on the recorded coordinate value and distance, after the sample was removed and then was reset on the sample stage of microscope. The in situ observation and relocation method can be applied in different microscope systems and different sample substrates, and will have potential applications in the manipulation and the secondary process of micro‐ and nano‐devices. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc.
Role of parietal and principal gastric mucosa cells in the phenomenon of concentration of aluminum and indium
Authors: Maghraoui Samira , Ayadi Ahlem , Audinot Jean‐Nicolas , Ammar Aouatef Ben , Jaafoura Mohamed‐Habib , Hili Ali El , Migeon Henri‐Noël , Tekaya Leila
Published: July 2011

The subcellular behavior of aluminum and indium, used in medical and industrial fields, was studied in the gastric mucosa and the liver after their intragastric administration to rats, using, two of the most sensitive methods of observation and microanalysis, the transmission electron microscopy, and the secondary ion mass spectrometry. The ultrastructural study showed the presence of electron dense deposits, in the lysosomes of parietal and principal gastric mucosa cells but no loaded lysosomes were observed in the different studied hepatic territories. The microanalytical study allowed the identification of the chemical species present in those deposits as aluminum or indium isotopes and the cartography of their distribution. No modification was observed in control rats tissues. In comparison to previous studies describing the mechanism of aluminum concentration in the gastric mucosa and showing that this element was concentrated in the lysosomes of fundic and antral human gastric mucosa, our study provided additional informations about the types of cells involved in the phenomenon of concentration of aluminum and indium, which are the parietal and the principal cells of the gastric mucosa. Our study demonstrated that these cells have the ability to concentrate selectively aluminum and indium in their lysosomes, as a defensive reaction against intoxication by foreign elements. Microsc. Res. Tech., 2011 © 2011 Wiley Periodicals, Inc.
Entamoeba histolyticaelectrondense granules secretion in vitro and in vivo: Ultrastructural study
Authors: ChÁvez‐munguÍa Bibiana , CastaÑÓN Guadalupe , HernÁNdez‐RamÍRez VerÓNica , GonzÁLez‐LÁZARO MÓNica , TalamÁS‐Rohana Patricia , MartÍNez‐Palomo Adolfo
Published: July 2011

Electron dense granules (EDGs) were identified by transmission electron microscopy in Entamoeba histolytica trophozoites recovered from hamster liver lesions. Abundant granules were present in trophozoites recovered after 15 min of liver inoculation. Variation in the size and morphology of these EDGs was also observed. Numerous granules were present in the plasma membrane when these parasites were incubated for 5 min with MDCK monolayers. Release of these EDGs was suggested by the presence of granules in contact with the surface of the target cell plasma membrane. Parasite phagocytic invaginations were observed after 10 min of parasite‐monolayer interaction. In these structures, scarce granules were seen. Granules secretion was corroborated by obtaining of a pellet of these small structures from the incubation of trophozoites with collagen supernatant. Collagenase and gellatinase activity of this pellet was identified in SDS‐PAGE gels. EDGs were also present in amebic hamster liver lesions. Our observations corroborate that these granules are secreted and suggest that may participate in the cytopathic effect of E. histolytica both in vitro and in vivo. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc.
Action of the chemical agent fipronil (active ingredient of acaricide Frontline®) on the liver of mice: An ultrastructural analysis
Authors: Ferreira Mateus , De Oliveira Patrícia Rosa , Denardi Sandra Eloisi , Bechara Gervásio Henrique , Mathias Maria Izabel Camargo
Published: July 2011

Fipronil, active ingredient of the acaricide Frontiline®, is a phenyl‐pyrazolic derivative, and its efficacy in the elimination of several plagues, even in low concentrations, has already been demonstrated; however, its effect on nontarget organisms has not been thoroughly explained. In this sense, the objective of this study was to evaluate the effects of different dosages of fipronil on the liver of mice in artificial conditions. Results showed that the animals exposed to fipronil present significant ultrastrucutural changes in hepatic cells with evident cellular and cytoplasm disorganization in hepatocytes characterized by an increase in the number of organelles, mainly mitochondria and rough endoplasmic reticulum, organelles that, in the case of the exposed animals, were probably responsible for the enzymes' synthesis that have the function of inactivating the toxic metabolites. A fat accumulation in the hepatocytes' cytoplasm (steatosis) was observed, in addition to extended vacuolated areas, mainly in regions next to the cell nucleus. Alterations observed in the nuclei of the hepatocytes pointed out cell death processes. Moreover, Kupffer cells increased in number (hyperplasia) suggesting an increase in the phagocytic activity of the liver in the exposed animals. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc.
Ultrastructure of immature stages of the blowflyChrysomya putoria(Wiedemann, 1818) (Diptera: Calliphoridae)
Authors: Mendonça Paloma Martins , Dos Santos‐Mallet Jacenir Reis , De Carvalho Queiroz Margareth Maria
Published: July 2011

Forensic entomology is an area of science that serves as a tool in crime scene investigations. Usually, flies are the first insects to reach a carcass and can oviposit just a few hours after arrival. Therefore, the knowledge of immature stages is essential for correct identification of the species found on corpses. Scanning electron microscopy (SEM) gives detailed information about morphological characters helping to identify the immature forms of flies.Chrysomya putoria(Wiedemann) is a very important fly for forensic entomology, because it has high population densities and is easily found in colonizing carcasses, moreover, it is also a possible causative agent for secondary myiasis. The aim of this study is to identify larvae and puparia ofC. putoriausing SEM. The first instar larvae were composed of 12 smooth segments separated by spines. Antennae and maxillary palps were visible. Anterior spiracle was absent and only one spiracular opening could be seen at the posterior spiracle. Second and third larval instars were similar to first instar, except for the presence of anterior spiracle that is composed by 11–12 spiracular ramifications. At the anal segment, two spiracular openings were found in second instars and three openings in third instar larvae. Puparia showed a retracted cephalic region and none of the head structures were visible. Microsc. Res. Tech. 2011., © 2011 Wiley Periodicals, Inc.
Chemical and morphological features of nanofilled composite resin: Influence of finishing and polishing procedures and fluoride solutions
Authors: de Oliveira Ana Luísa Botta Martins , Domingos Patrícia Aleixo Dos Santos , Palma‐Dibb Regina Guenka , Garcia Patrícia Petromilli Nordi Sasso
Published: July 2011

This study evaluated the influence of finishing and polishing procedures and different fluoride solutions on superficial morphology and chemistry of the nanofilled composite resin Supreme XT (3M) through the EDX analysis and SEM evaluation. Circular specimens (n= 30) of 10 mm diameter and 2 mm thickness were prepared, with half of the sample assays finished and polished with Super‐Snap® sandpaper. The experimental groups were divided according to the presence or absence of finishing and polishing and solutions (artificial saliva, 0.05% of manipulated sodium fluoride solution, Fluordent Reach, Oral B, Fluorgard). Specimens were immersed in each respective solution for 1 min per day, during 60 days and stored in artificial saliva at 37 ± 1°C between immersion periods. Topography and chemical analysis was qualitative. It was observed that specimens submitted to finishing and polishing procedures had lower superficial degradation. Fluoride solutions promoted superficial alterations on specimens, being the highest degradation obtained with Fluordent Reach. It can be concluded that finishing and polishing procedures and the immersion media influence the superficial morphology of composite resin tested; the Fluordent Reach was the fluoride solution that most affected the material's surface. Microsc. Res. Tech. 2011., © 2011 Wiley Periodicals, Inc.
Intracellular trafficking and fate of chimeric adenovirus 5/F35 in human B lymphocytes
Authors: Samson Mélanie , Jung Daniel
Published: July 2011

Background

Investigation of the molecular processes that control the development and function of lymphocytes is essential for our understanding of humoral immunity, as well as lymphocyte‐associated pathogenesis. Adenovirus‐mediated gene transfer provides a powerful tool for investigating these processes. However, we observed variation in transgene expression among normal human peripheral blood B lymphocytes from different donors and at distinct stages of differentiation. It is recognized that efficient gene transfer is highly dependent on the intracellular route by which the viruses travel within the host cell. Thus, we aimed to examine this aspect in the present study.

Methods

We analyzed the binding, uptake, intracellular trafficking and fate of CY3‐labelled Ad5/F35 vectors in lymphoid cell lines and primary B cells. Furthermore, we decreased protein synthesis levels and rapid endocytosis in a plasma cell line exhibiting a high level of protein synthesis activity and activated transcription and endocytosis in primary B cells, which are less active than plasma cells.

Results

Major differences in intracellular trafficking pattern between B cells and plasma cell line U266 were identified that explain the observed divergence in transgene expression efficiency. Importantly, modification of the transcriptional or translational activity of U266 cells reverted the Ad5/F35 endocytic trafficking to that seen in B cells, with a loss of transgene expression, whereas activation of B cells with phorbol 12‐myristate 13‐acetate had the opposite effects.

Conclusions

Taken together, these results suggest that Ad5/F35 is more efficiently transduced in cells with a strong transcriptional activity as a result of differences in intracellular trafficking. This finding extends our current knowledge of the mechanisms of adenovirus‐mediated gene transfer. Copyright © 2011 John Wiley & Sons, Ltd.
Sleeping Beauty‐mediated correction of Fanconi anemia type C
Authors: Hyland Kendra A. , Olson Erik R. , Clark Karl J. , Aronovich Elena L. , Hackett Perry B. , Blazar Bruce R. , Tolar Jakub , Scott McIvor R.
Published: July 2011

Background

The Sleeping Beauty (SB) transposon system can insert defined sequences into chromosomes to direct the extended expression of therapeutic genes. Our goal is to develop the SB system for nonviral complementation of Fanconi anemia (FA), a rare autosomal recessive disorder accompanied by progressive bone marrow failure.

Methods

We used a CytoPulse electroporation system (CytoPulse, Glen Burnie, MD, USA) to introduce SB transposons into human lymphoblastoid cells (LCL) derived from both Fanconi anemia type C (FA‐C) defective and normal patients. Correction of the FA‐C defect was assessed by resistance to mitomycin C, a DNA‐crosslinking agent.

Results

Culture of both cell types with the antioxidant N‐acetyl‐ l‐cysteine improved cell viability after electroporation. Co‐delivery of enhanced green fluorescent protein (GFP) transposon with SB100X transposase‐encoding plasmid supported a 50‐ to 90‐fold increase in stable GFP expression compared to that observed in the absence of SB100X for normal LCL, but in FA‐C defective LCL SB100X enhancement of stable GFP‐expression was a more moderate five‐ to 13‐fold. SB‐mediated integration and expression of the FA‐C gene was demonstrated by the emergence of a mitomycin C‐resistant population bearing characteristic transposon‐chromosome junction sequences and exhibiting a mitomycin dose response identical to that of normal LCL.

Conclusions

The SB transposon system achieved stable expression of therapeutic FA‐C genes, complementing the genetic defect in patient‐derived cells by nonviral gene transfer. Copyright © 2011 John Wiley & Sons, Ltd.