bluuebunny/crossref_metadata_2025 huggingface dataset:
Can two (environmental) wrongs make a right? The reaction of anthropogenic waste CO2 and NH3 to form NH2COOH
Authors: Tossell J.A.
Published: December 2010

Antropogenic waste CO2 and NH3 both provide enormous environmental challenges. The amount of CO2 emitted by fossil fuel power plants is now about an order of magnitude larger than the NH3 processed by waste water treatment plants but the NH3 production is growing faster than CO2 production. Recent experimental and theoretical studies have established that CO2 and NH3 react without additional energy input to form carbamic acid, NH2COOH, which exists primarily as a dimer when adsorbed on a cryogenic surface. Might it be possible to react effluent streams of CO2 and NH3 to form carbamic acid and then to store the carbamic acid (or use it as a source for other industrial chemicals)? Can two environmental wrongs make a right? © 2010 American Institute of Chemical Engineers Environ Prog, 2010
Treatment performance evaluation of chemical oxygen demand from landfill leachate by electro‐coagulation and electro‐fenton technique
Authors: Orkun Merve Oya , Kuleyin Ayşe
Published: December 2010

The removal of chemical oxygen demand (COD) from landfill leachate by electro‐coagulation (EC) using iron sacrificial anode has been investigated. The process performance is analyzed in terms of COD removal efficiency and the important cost‐related parameters such as electrode and energy consumptions, as a function of initial pH, conductivity, current density, and operation time. The optimum COD removal (65.85%) was obtained with typical operating conditions: current density, 30 mA/cm2; operation time, 180 min; conductivity, 16.4 ms/cm; and initial pH, 6.54. At these conditions, the electrode and energy consumptions during the electrolysis were determined as 0.418 kg COD/kg Al and 11.092 kWh/kg COD, respectively. In addition, the EC and Fenton processes are applied together referred to as the electro‐Fenton process in the literature for the removal of COD from landfill leachate and effect of operation time and hydrogen peroxide concentration is examined. The process was very fast in the first 15 min, and then it slowed down till it was complete in 60 min. An optimum COD removal efficiency of 74.21% was obtained at 5000 ppm hydrogen peroxide dosage and 60 min. © 2010 American Institute of Chemical Engineers Environ Prog, 2012
A study on the measurement of mean velocity and its convergence in molecular dynamics simulations
Authors: Karimian S. M. H. , Izadi S. , Farimani A. Barati
Published: December 2010

In many particle‐based simulations, measurement of local mean flow velocity and other continuum‐based properties are of utmost importance. Macroscopic quantities, such as mean flow velocity, temperature, and density, can be estimated by averaging the corresponding microscopic behavior of the particles. The two main subjects that should be considered in the averaging over the particles in a specific problem are spatial and temporal behaviors of them. In this paper, we study the latter. Because of the chaotic nature of the collisions among the molecules and consequently their random path, extracted macroscopic values fluctuate about their average values causing statistical errors. In this paper, an averaging method called SAM‐Modified‐CAM (SMC) will be proposed for the measurement of mean velocity that reduces statistical errors in its calculation. This proposal is based on the study conducted here on the implementations of two common averaging methods, sample‐averaged measurement (SAM) and cumulative average measurement (CAM) in molecular dynamics. In addition, convergence of mean flow velocity measurement is thoroughly discussed, and a convergence criterion is proposed for this purpose. Implementation of the proposed method in different test cases has approved its reliable performance. Copyright © 2010 John Wiley & Sons, Ltd.
The use of Sinc‐collocation method for solving Falkner–Skan boundary‐layer equation
Authors: Parand K. , Dehghan Mehdi , Pirkhedri A.
Published: December 2010

The MHD Falkner–Skan equation arises in the study of laminar boundary layers exhibiting similarity on the semi‐infinite domain. The proposed approach is equipped by the orthogonal Sinc functions that have perfect properties. This method solves the problem on the semi‐infinite domain without truncating it to a finite domain and transforming domain of the problem to a finite domain. In addition, the governing partial differential equations are transformed into a system of ordinary differential equations using similarity variables, and then they are solved numerically by the Sinc‐collocation method. It is shown that the Sinc‐collocation method converges to the solution at an exponential rate. Copyright © 2010 John Wiley & Sons, Ltd.
A method to compute ship exhaust plumes with waves and wind
Authors: Huang Juntao , Carrica Pablo M. , Stern Frederick
Published: December 2010

Thermal and concentration transport models are implemented in CFDShip‐Iowa version 4.5, a semi‐coupled solver for air/water free surface flow (Int. J. Numer. Meth. Fluids 2008; 58(6):591–624), to investigate the exhaust plume around ship superstructures. An incompressible, variable density approximation is implemented where the density can change in all governing equations due to temperature variations only. The thermal and concentration models are tested for the cases of steady and unsteady flow with thermal and solution transport in a 2D square cavity, and for a 3D thermal plume in an open environment, showing good agreement between computational results and experimental data. To test the method in an extreme motions condition, the exhaust plume of the ONR Tumblehome model DTMB 5613 is studied, showing complicated vortical structures in air including a pair of counter‐rotating vortices downstream of the stack for cross‐flow, and bended bird‐plume shape in the symmetry plane and varying arc‐shape in axial sections both for temperature and NOx concentration fields. Effects of smoke exhaust speed and wind speed on the temperature and concentration distributions are studied. Finally, a smoke downwash computation is performed for a ship free to move in 6 degrees of freedom in a sea state 8 condition. Copyright © 2010 John Wiley & Sons, Ltd.
Effect of salt additives on film boiling heat transfer and mechanism of quenching temperature rise
Authors: Arai Takahiro , Furuya Masahiro
Published: December 2010

A high‐temperature stainless‐steel sphere was immersed into various salt solutions to investigate the film boiling behavior at vapor film collapse. The film boiling behavior around the sphere was observed with a digital video camera. Both surface temperature of the sphere and solid–liquid contact behavior were measured. Results of the experiment showed that salt additives enhanced condensation heat transfer, and the observed vapor film was thinner. Furthermore, the frequency of direct contact between the sphere surface and coolant increased. The quenching temperature increased with increased salt concentration, and was highly correlated with ion molar concentration, which represents the density of ions regardless of the type of salt. © 2010 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/htj.20327
Enhancement of nucleate pool boiling heat transfer in ammonia/water mixtures (Effect of surface‐active agent)
Authors: Inoue Toshiaki , Monde Masanori , Kuwahara Teruki , Teruya Yoshio
Published: December 2010

Nucleate boiling heat transfer coefficients of ammonia/water mixtures have been measured when a surface‐active agent was added into the mixtures. The experiment has been carried out on a horizontal heated wire at a pressure of 0.4 MPa. The effect of concentration of the ammonia and the surface‐active agent on the coefficients was investigated experimentally for the ammonia fractions C = 0.3 and 0.7 and the surfactant concentration CS = 0 to 3500 ppm. The result shows that just after onset of boiling the nucleate boiling heat transfer coefficient enhances at the lower ammonia fraction i.e., C = 0.3. It was found that the enhancement effect by the surface‐active agent disappeared when the surfactant concentration is more than 1000 ppm at an ammonia fraction C = 0.3.

It is also shown that the generated heat of mixing near the vaporBliquid interface can be removed easily and the pressure and temperature in the system can be controlled easily by placing a cooling pipe on the vaporBliquid interface, resulting in improvement of accuracy in measuring the heat transfer coefficients. We correlated the effect of the surfactant on the heat transfer coefficient using the improved measurement data in the current paper. 8 2010 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/htj.20328
Application of γ‐Reθ transition model for internal cooling simulation
Authors: Li Lin , Jing Ren , Hongde Jiang
Published: December 2010

The aero thermodynamics of the flow field in a cascade with an internal cooling system plays a big role in the whole efficiency of a gas turbine. For an accurate numerical analysis, this transition is one of the main obstacles. In the present work, the γ− Reθ transition model combined with the SST turbulence model is applied to analyze the heat transfer of the Mark II blade. The prediction of the onset of the turbulence layer is proven to be satisfied, while the distribution of the blade surface temperature before the transition is also captured through the model. Meanwhile, it is pointed out that the turbulent kinetic energy might be over‐suppressed in the laminar layer before the bypass transition due to the combination of the transition model and the turbulence model. 8 2010 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/htj.20331 5
Subsurface lateral flow generation in aspen and conifer‐dominated hillslopes of a first order catchment in northern Utah
Authors: Burke Amy R. , Kasahara Tamao
Published: December 2010

Mountain headwater catchments in the semi‐arid Intermountain West are important sources of surface water because these high elevations receive more precipitation than neighboring lowlands. This study examined subsurface runoff in two hillslopes, one aspen dominated, the other conifer dominated, adjacent to a first order stream in snow‐driven northern Utah. Snow accumulation, soil moisture, trenchflow and streamflow were examined in hillslopes and their adjacent stream. Snow water equivalents (SWEs) were greater under aspen stands compared to conifer, the difference increasing with higher annual precipitation. Semi‐variograms of shallow spatial soil moisture patterns and transects of continuous soil moisture showed no increase in soil moisture downslope, suggesting the absence of subsurface flow in shallow (∼12 cm) soil layers of either vegetation type. However, a clear threshold relationship between soil moisture and streamflow indicated hillslope–stream connectivity, deeper within the soil profile. Subsurface flow was detected at ∼50 cm depth, which was sustained for longer in the conifer hillslope. Soil profiles under the two vegetation types varied, with deep aspen soils having greater water storage capacity than shallow rocky conifer soils. Though SWEs were less under the conifers, the soil profile had less water storage capacity and produced more subsurface lateral flow during the spring snowmelt. Copyright © 2010 John Wiley & Sons, Ltd.
Assessment of GCM simulations of annual and seasonal rainfall and daily rainfall distribution across south‐east Australia
Authors: Vaze J. , Teng J. , Chiew F. H. S.
Published: December 2010

Global warming can potentially lead to changes in future rainfall and runoff and can significantly impact the regional hydrology and future availability of water resources. All the large‐scale climate impact studies use the future climate projections from global climate models (GCMs) to estimate the impact on future water availability. This paper presents results from a detailed assessment to investigate the capability of 15 GCMs to reproduce the observed historical annual and seasonal mean rainfalls, the observed annual rainfall series and the observed daily rainfall distribution across south‐east Australia. The assessment shows that the GCMs can generally reproduce the spatial patterns of mean seasonal and annual rainfalls. However, there can be considerable differences between the mean rainfalls simulated by the GCMs and the observed rainfall. The results clearly show that none of the GCMs can simulate the actual annual rainfall time series or the trend in the annual rainfall. The GCMs can also generally reproduce the observed daily (ranked) rainfall distribution at the GCM scale. The GCMs are ranked against their abilities to reproduce the observed historical mean annual rainfall and daily rainfall distribution, and, based on the combined score, the better GCMs include MPI‐ECHAM5, MIUB, CCCMA_T47, INMCM, CSIRO‐MK3·0, CNRM, CCCMA_T63 and GFDL 2·0 and those with poorer performances are MRI, IPSL, GISS‐AOM, MIROC‐M, NCAR‐PCM1, IAP and NCAR‐CCSM. However, the reduction in the combined score as we move from the best‐ to the worst‐performing GCMs is gradual, and there is no evident cut‐off point or threshold to remove GCMs from climate impact studies. There is some agreement between the results here and many similar studies comparing the performance of GCMs in Australia, but the results are not always consistent and do significantly disagree with several of the studies. Copyright © 2010 John Wiley & Sons, Ltd.
Low‐cost monitoring of snow height and thermal properties with inexpensive temperature sensors
Authors: Reusser Dominik E. , Zehe Erwin
Published: December 2010

Small, self‐recording temperature sensors were installed at several heights along a metal rod at five locations in a case study catchment. For each sensor, the presence or absence of snow cover was determined on the basis of its insulating effect and the resulting reduction of the diurnal temperature oscillations. Sensor coverage was then converted into a time series of snow height for each location. Additionally, cold content was calculated. Snow height and cold content provide valuable information for spring flood prediction.

Good agreement of estimated snow heights with reference measurements was achieved and increased discharge in the study catchment coincided with low cold content of the snow cover. The results of the proposed distributed assessment of snow cover and snow state show great potential for (i) flood warning, (ii) assimilation of snow state data and (iii) modelling snowmelt process. Copyright © 2010 John Wiley & Sons, Ltd.
FLIM and FCS detection in laser‐scanning microscopes: Increased efficiency by GaAsP hybrid detectors
Authors: Becker W. , Su B. , Holub O. , weisshart K.
Published: December 2010

Photon counting detectors currently used in fluorescence lifetime microscopy have a number of deficiencies that result in less‐than‐ideal signal‐to‐noise ratio of the lifetimes obtained: Either the quantum efficiency is unsatisfactory or the active area is too small, and afterpulsing or tails in the temporal response contribute to overall timing inaccuracy. We have therefore developed a new FLIM detector based on a GaAsP hybrid photomultiplier. Compared with conventional PMTs and SPADs, GaAsP hybrid detectors have a number of advantages: The detection quantum efficiency reaches or surpasses the efficiency of fast SPADs, and the active area is on the order of 5 mm2, compared with 2.5 10−3 mm2 for a SPAD. The TCSPC response is clean, without the bumps and the diffusion tails typical for PMTs and SPADs. Most important, the hybrid detector is intrinsically free of afterpulsing. FLIM results are therefore free of signal‐dependent background, and FCS curves are free of the known afterpulsing peak. We demonstrate the performance of the new detector for multiphoton NDD FLIM and for FCS. Microsc. Res. Tech., 2011. © 2010 Wiley‐Liss, Inc.
Enhanced effects of nonisotopic hafnium chloride in methanol as a substitute for uranyl acetate in TEM contrast of ultrastructure of fungal and plant cells
Authors: Ikeda Ken‐Ichi , Inoue Kanako , Kanematsu Satoko , Horiuchi Yoshitaka , Park Pyoyun
Published: December 2010

This ultrastructural study showed that nonisotopic methanolic hafnium chloride and aqueous lead solution was an excellent new electron stain for enhancing TEM contrasts of fungal and plant cell structures. The ultrastructural definition provided by the new stain was often superior to that provided by conventional staining with uranyl acetate and lead. Definition of fine ultrastructure was also supported by quantitative data on TEM contrast ratios of organelles and components in fungal and plant cells. In particular, polysaccharides, which were localized in cell walls, glycogen particles, starch grains, and plant Golgi vesicle components, were much more reactive to the new stain than to the conventional one. The new nonisotopic stain is useful for enhancing the contrast of ultrastructure in biological tissues and is a safer alternative to uranyl acetate. Microsc. Res. Tech., 2011. © 2010 Wiley‐Liss, Inc.
Compensation of inhomogeneous fluorescence signal distribution in 2D images acquired by confocal microscopy
Authors: Michálek Jan , Čapek Martin , Kubínová Lucie
Published: December 2010

In images acquired by confocal laser scanning microscopy (CLSM), regions corresponding to the same concentration of fluorophores in the specimen should be mapped to the same grayscale levels. However, in practice, due to multiple distortion effects, CLSM images of even homogeneous specimen regions suffer from irregular brightness variations, e.g., darkening of image edges and lightening of the center. The effects are yet more pronounced in images of real biological specimens. A spatially varying grayscale map complicates image postprocessing, e.g., in alignment of overlapping regions of two images and in 3D reconstructions, since measures of similarity usually assume a spatially independent grayscale map. We present a fast correction method based on estimating a spatially variable illumination gain, and multiplying acquired CLSM images by the inverse of the estimated gain. The method does not require any special calibration of reference images since the gain estimate is extracted from the CLSM image being corrected itself. The proposed approach exploits two types of morphological filters: the median filter and the upper Lipschitz cover. The presented correction method, tested on images of both artificial (homogeneous fluorescent layer) and real biological specimens, namely sections of a rat embryo and a rat brain, proved to be very fast and yielded a significant visual improvement. Microsc. Res. Tech., 2011. © 2010 Wiley‐Liss, Inc.
Novel synthetic protocol toward pyrazolo[3,4‐h]‐[1,6]naphthyridines via Friedlander condensation of new 4‐aminopyrazolo[3,4‐b]pyridine‐5‐carbaldehyde with reactive α‐methylene ketones
Authors: Jachak Madhukar N. , Bagul Sandeep M. , Kazi Muddassar A. , Toche Raghunath B.
Published: December 2010

Novel pyrazolo[3,4‐h][1,6]naphthyridine derivatives 6, 8, 9, 11, 13, and 15 have been synthesized by Friedlander condensation of new 4‐amino‐3‐methyl‐1‐phenyl‐1H‐pyrazolo[3,4‐b]pyridine‐5‐carbaldehyde (o‐aminoaldehyde) 4 with active methylene ketones, such as symmetric acetone 5a, monoalkylketones 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, unsymmetrical dialkyl ketones 7a, 7b, p‐bromophenylacetonitrile 10, β‐ketoester 12a, β‐ketoamide 12b, or diethyl malonate 14, respectively. J. Heterocyclic Chem., (2011).
Sodium cromolyn reduces expression of CTGF, ADAMTS1, and TIMP3 and modulates post‐injury patellar tendon morphology
Authors: Sharma Aishwariya , Abraham Thomas , Sampaio Arthur , Cowan Matthew , Underhill Michael , Scott Alexander
Published: December 2010

The purpose of this study was to determine whether administration of a mast cell inhibitor (sodium cromolyn, SC) would influence tendon repair and extracellular matrix gene expression following acute injury. CD1 mouse patellar tendons were unilaterally injured and mast cell prevalence was determined. The effect of SC injection on tendon hypercellularity, cross‐sectional area, collagen organization, and expression of extracellular matrix‐related genes was examined. Mast cell prevalence was markedly increased in injured patellar tendons (p = 0.009), especially at 8 weeks post‐injury (p = 0.025). SC injection increased collagen organization compared to uninjected animals at 4 weeks and attenuated the development of tendon hypercellularity and tendon thickening post‐injury. Expression of CTGF, ADAMTS1, and TIMP3 in injured tendon was reduced in the SC group. SC injections moderated the structural alterations of healing tendon in association with downregulation of several genes associated with tendon fibrosis. This work corroborates previous findings pointing to a role of mast cells in tendon repair. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 29:678–683, 2011
High‐performance purification of quaternary alkaloids from Corydalis yanhusuo W. T. Wang using a new polar‐copolymerized stationary phase
Authors: Wang Chaoran , Guo Zhimou , Zhang Jing , Zeng Jing , Zhang Xiuli , Liang Xinmiao
Published: December 2010

An efficient method for purification of alkaloids from Corydalis yanhusuo W. T. Wang using HPLC was developed, featuring a polar‐copolymerized stationary phase named C18HCE. As ionizable solutes, the crude alkaloid sample often suffered from serious peak tailing problem on conventional RP‐LC columns, and the separation would rapidly became destroyed with the increasing of load amount. However, on the new stationary phase, good peak shapes (asymmetry factor <1.5) as well as good loadability were easily obtained in a commonly used acidic mobile phase condition. The loading amount could reach 10 mg per injection on an analytical C18HCE column for laboratory‐scale purification. About 6.8 mg of palmatine (HPLC purity >98%) and 44.4 mg of dehydrocorydaline (HPLC purity >98%) were rapidly derived from 200 mg of the crude alkaloid sample, and the recoveries of these two compounds were 76.5 and 81.7%, respectively. The purified alkaloids were characterized by comparing retention times with standard compounds as well as 1H‐NMR data. The new method is simple and high yielding, and it may provide a promising tool for purification of alkaloids as well as other alkaline compounds.
Release of cytokines and hemodynamic instability during the reperfusion of a liver graft
Authors: Bezinover Dmitri , Kadry Zakiyah , McCullough Paul , McQuillan Patrick M. , Uemura Todahiro , Welker Kelli , Mastro Andrea M. , Janicki Piotr K.
Published: December 2010

The objectives of this prospective, observational study were (1) to determine whether a transplanted liver graft releases proinflammatory cytokines into the systemic circulation upon reperfusion and (2) to determine whether they contribute to any subsequent hemodynamic instability observed after graft reperfusion (if this release occurs). Blood samples from 17 consecutive patients undergoing liver transplantation were analyzed for cytokines, including tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), IL-2, IL-6, and IL-8. Blood samples were obtained from the radial artery, portal vein, and flush blood (a sample taken from a catheter placed above the infrahepatic inferior vena cava clamp). The amount of catecholamines necessary to maintain a mean arterial pressure between 65 and 75 mm Hg during graft reperfusion was compared with the level of cytokines. A statistical analysis was performed with the least squares method, Kendall's tau-b test, and regression analysis. We demonstrated that flush blood from the liver grafts contained a significant amount and variety of cytokines. Most of these were removed by graft irrigation. The concentration of TNF-α in samples obtained from flush blood at the end of liver irrigation was significantly higher than the concentration in samples obtained from the radial artery (P = 0.0067) or portal vein (P = 0.0003) before reperfusion. This correlated directly with the amount of catecholamines used to treat hemodynamic instability. Although there were increased levels of IL-1β, IL-2, and IL-8 in the flush blood, there was no statistically significant correlation between the levels of these cytokines and the amount of catecholamines used. Liver Transpl, 2011. © 2011 AASLD.
The model for end-stage liver disease allocation system for liver transplantation saves lives, but increases morbidity and cost: a prospective outcome analysis
Authors: Dutkowski Philipp , Oberkofler Christian E. , Béchir Markus , Müllhaupt Beat , Geier Andreas , Raptis Dimitri A. , Clavien Pierre-Alain
Published: December 2010

We analyzed the first 100 patients who underwent liver transplantation by Model for End-Stage Liver Disease (MELD) allocation, and compared the outcome of patients on the waiting list and after orthotopic liver transplantation with the last 100 patients who underwent transplantation prior to the introduction of the MELD system in July 2007. MELD allocation resulted in decreased waiting list mortality (386 versus 242 deaths per 1000 patient-years, P < 0.0001) and the transplantation of sicker recipients (uncorrected median MELD score 13.5 versus 20, P = 0.003). Recipient posttransplant morbidity was significantly higher, mainly caused by increased percentage of renal failure requiring renal replacement therapy (13 versus 46%, P < 0.0001). However, kidney function recovered in most cases within 6 months after OLT. Hospital mortality remained similar in both groups (6% versus 9%). Patient 1-year survival was 91% versus 83% (pre-MELD versus MELD era, P = 0.2154), graft 1-year survival was 88% versus 78% (P = 0.1013), respectively. Costs accumulated were significantly higher after introduction of the MELD policy (US $81,967 versus US $127,453, a 55% increase, P = 0.02) with a strong correlation with the individual MELD score (P < 0.0001). The MELD system addresses the goal of fairness well. However, the postoperative course appears more difficult in the MELD era with increased financial burden, but reasonable patient and graft survival. This is the inevitable price to balance justice and utility in liver graft allocation. Liver Transpl 17:674–684, 2011. © 2011 AASLD.
The interaction among donor characteristics, severity of liver disease, and the cost of liver transplantation
Authors: Salvalaggio Paolo R. , Dzebisashvili Nino , MacLeod Kara E. , Lentine Krista L. , Gheorghian Adrian , Schnitzler Mark A. , Hohmann Samuel , Segev Dorry L. , Gentry Sommer E. , Axelrod David A.
Published: December 2010

Accurate assessment of the impact of donor quality on liver transplant (LT) costs has been limited by the lack of a large, multicenter study of detailed clinical and economic data. A novel, retrospective database linking information from the University HealthSystem Consortium and the Organ Procurement and Transplantation Network registry was analyzed using multivariate regression to determine the relationship between donor quality (assessed through the Donor Risk Index [DRI]), recipient illness severity, and total inpatient costs (transplant and all readmissions) for 1 year following LT. Cost data were available for 9059 LT recipients. Increasing MELD score, higher DRI, simultaneous liver-kidney transplant, female sex, and prior liver transplant were associated with increasing cost of LT (P < 0.05). MELD and DRI interact to synergistically increase the cost of LT (P < 0.05). Donors in the highest DRI quartile added close to $12,000 to the cost of transplantation and nearly $22,000 to posttransplant costs in comparison to the lowest risk donors. Among the individual components of the DRI, donation after cardiac death (increased costs by $20,769 versus brain dead donors) had the greatest impact on transplant costs. Overall, 1-year costs were increased in older donors, minority donors, nationally shared organs, and those with cold ischemic times of 7-13 hours (P < 0.05 for all). In conclusion, donor quality, as measured by the DRI, is an independent predictor of LT costs in the perioperative and postoperative periods. Centers in highly competitive regions that perform transplantation on higher MELD patients with high DRI livers may be particularly affected by the synergistic impact of these factors. Liver Transpl, 2011. © 2011 AASLD.
Absolute integrity is the basis of heroic leadership
Authors: Cohen William A.
Published: December 2010

Subordinates will forgive a leader almost any mistake, except a lack of integrity, William A. Cohen argues. “Don't say ‘it is a jungle out there’ and that you have to make compromises. Follow the path of integrity. Do this and others in your organization will do it too and you will build the foundation that can and will make a difference not only in your organization, but also in society as a whole,” Cohen says. Citing a wide variety of leaders who displayed absolute integrity, Cohen challenges us all to live up to their example.
Twenty years of experience with corrosion failures caused by manganese oxidizing microorganisms
Authors: Linhardt P.
Published: December 2010

Manganese oxidizing microorganisms are known as ubiquitous species in soil and fresh water. Their ability to extract dissolved manganese even at minute concentrations from the water and to biomineralize it as manganese(III/IV)oxides makes them potentially relevant for corrosion processes in technical systems carrying freshwater. These oxides are known as strong oxidants and may act as catalyst for the oxygen reduction reaction. Thus, they are cathodically active, possibly driving anodic metal dissolution processes. The personal experiences over two decades from failure analysis related to these organisms have indeed shown that manganese oxidizers may appear in all kinds of freshwater systems. This paper summarizes observations and conclusions drawn from these cases and provides an overview on the methods found useful in their investigation.
Coatings against corrosion and microbial adhesion
Authors: Telegdi J. , Szabó T. , Al‐Taher F. , Pfeifer É. , Kuzmann E. , Vértes A.
Published: December 2010

A systematic study on anti‐corrosion and anti‐fouling effect of hydrophobic Langmuir–Blodgett and self‐assembled molecular layers deposited on metal surfaces, as well as anti‐microbial adhesion properties of coatings with biocide is presented. Both types of efficiencies produced by LB films are enhanced by Fe3+ ions built in the molecular film. The quaternary ammonium type biocide embedded into the cross‐linked gelatin decreased significantly the microbial adhesion, the biofilm formation.
Electrochemical study of AISI 304 stainless steel during the exposure at the disinfectant solutions with fungal suspensions
Authors: Stoica M. , Brumă M. , Cârâc G.
Published: December 2010

The effect of fungal suspensions on the disinfectant solution (Actisept with sodium dichloroisocyanurate as active substance, which releases 140 ppm active chlorine) and the corrosion behavior of type AISI 304 stainless steel (SS) were evaluated through linear polarization. The work presents a study of biocide Actisept solution as reference solution and the mixed solutions: reference biocide Actisept solution with three fungal suspensions (10 vol%), Aspergillus niger, Candida mycoderma, and Saccharomyces cerevisiae. The fungal suspension has an important influence on the synergistic effect of the SS corrosion in the following order: Saccharomyces cerevisiae > Candida mycoderma > Aspergillus niger. The Ecorr values from the mixed solutions decreased with immersion time of the samples. In the case of Aspergillus niger, the corrosion rate was lower than that of any other type of fungal suspension tested, because the arrangement in solutions, the size and composition of Aspergillus niger spores were more favorable to protect the spores of the chemical and the electrical stressing. The results showed that there is a synergistic effect between the active substances from the disinfectant, fungal suspensions and applied potential, thus this effect can be taken into consideration for the hygienic and safety food industry.
Poly[2,7‐(9,9‐dihexylfluorene)]‐block‐Poly(2‐vinylpyridine) Rod–Coil Star‐block Copolymers: Synthesis, Micellar Structures, and Photophysical Properties
Authors: Li Dian‐Han , Lin Chia‐Hung , Chen Ching‐Yi , Hsu Jung‐Ching , Chiu Yu‐Cheng , Chang Wei‐Tsuan , Chen Wen‐Chang
Published: December 2010

The first successful synthesis of conjugated rod–coil star block copolymer, (PF‐b‐P2VP)n, containing conjugated poly[2,7‐(9,9‐dihexylfluorene)] (PF), and coil‐like poly(2‐vinylpyridine) (P2VP) by combining a Suzuki coupling reaction and living anionic polymerization is reported. With increasing methanol content in THF/methanol mixtures (PF‐b‐P2VP)n symmetric star‐block copolymers maintain spherical micelles, but PF‐b‐P2VP asymmetric diblock copolymers vary from spherical micelles to vesicles. Both the absorption and emission spectra of PF‐b‐P2VP blue shift with increasing methanol content, suggesting an “H‐type” aggregation. However, (PF‐b‐P2VP)n star‐block exhibits no shift in absorption but a red shift in the emission spectra, indicating a different type of aggregation. These results suggest the significance of polymer architectures on microphase‐separated morphologies and photophysical properties.

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Nanocatalysis in Polyamide 6.6 Solid‐State Polymerization
Authors: Boussia Anastasia C. , Konstantakopoulou Maria O. , Vouyiouka Stamatina N. , Papaspyrides Constantine D.
Published: December 2010

Solid‐state polymerization (SSP) of a poly(hexamethyleneadipamide) (PA 6.6)/clay nanocomposite system was studied. SSP runs were performed in a fixed‐bed reactor, at temperatures 160–200 °C and reaction times up to 8 h. The influence of clay presence on the PA 6.6 SSP rate constant was herewith quantified for the first time to prove significant acceleration of the SSP process. A catalysis mechanism was suggested, according to which the positive effect of clay is of a synergistic origin attributed to nucleated crystal morphology, that increased the concentration of reactive end groups in the amorphous regions, to chain extension performed by clay SiOH groups, and to thermal protection of the polyamide matrix due to the presence of the nanoparticles.

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Highly Extensible Bio‐Nanocomposite Fibers
Authors: Gaharwar Akhilesh K. , Schexnailder Patrick J. , Dundigalla Avinash , White James D. , Matos‐Pérez Cristina R. , Cloud Joshua L. , Seifert Soenke , Wilker Jonathan J. , Schmidt Gudrun
Published: December 2010

Here, we show that a poly(ethylene oxide) polymer can be physically cross‐linked with silicate nanoparticles (Laponite) to yield highly extensible, bio‐nanocomposite fibers that, upon pulling, stretch to extreme lengths and crystallize polymer chains. We find that both, nanometer structures and mechanical properties of the fibers respond to mechanical deformation by exhibiting strain‐induced crystallization and high elongation. We explore the structural characteristics using X‐ray scattering and the mechanical properties of the dried fibers made from hydrogels in order to determine feasibility for eventual biomedical use and to map out directions for further materials development.

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Dynamic Random Access Memory Effect and Memory Device Derived from a Functional Polyimide Containing Electron Donor‐Acceptor Pairs in the Main Chain
Authors: Tian Guofeng , Wu Dezhen , Qi Shengli , Wu Zhanpeng , Wang Xiaodong
Published: December 2010

A functional polyimide, hexafluoroisopropyl bis(phthalic dianhydride)/3,6‐diaminocarbazole (6FDA/DAC), in which DAC serves as electron donor and 6FDA as electron acceptor, has been synthesized in our present work. Electrical characterization results on the sandwiched polyimide memory device (ITO/Thin polyimide Layer/Au) indicate that the polyimide possesses electrical bistability and the device exhibits two accessible conductivity states, which can be reversibly switched from the low‐conductivity (OFF) state to the high‐conductivity (ON) state with an ON/OFF current ratio of about 104. Different from the widely reported write‐once‐read‐many‐times (WORM) effects, the device with the 6FDA/DAC polyimide as the active layer shows dynamic random access memory (DRAM) behavior. The ON state of the device was lost immediately after removal of the applied voltage, while by applying a constant bias (e.g., 3 V) the ON state can be electrically sustained. The roles of donor and acceptor components in the polyimide main chain were elucidated through molecular simulation.

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Hyperbranched Polycarbonate‐Based Multimolecular Micelle with Enhanced Stability and Loading Efficiency
Authors: Su Wei , Luo Xiao‐hua , Wang Hua‐fen , Li Lei , Feng Jun , Zhang Xian‐Zheng , Zhuo Ren‐xi
Published: December 2010

We herein develop a facile catalyst‐free method to prepare hyperbranched hydroxyl‐enriched aliphatic polycarbonate according to SCROP strategy. PEG‐attached multiarm hyperbranched copolymer HEHDO‐star‐mPEG was further designed. It was found that HEHDO‐star‐mPEG can self‐assemble into supramolecular multimolecular micelles in water. HEHDO‐star‐mPEG micelle showed excellent stability with respect to micellar size upon dilution, and displayed good cell‐biocompatibility. An anticancer drug of doxorubicin with hydrogen‐bonding functionality was incorporated into obtained micelles to establish a drug delivery system model. A high drug‐loading content as well as sustained release pattern for HEHDO‐star‐mPEG based delivery system was achieved.

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Reinnervation of thenar muscle after repair of total brachial plexus avulsion injury with contralateral C7 root transfer: Report of five cases
Authors: Wang Li , Zhao Xin , Gao Kaiming , Lao Jie , Gu Yu‐Dong
Published: December 2010

Objective:

In this report, we present the findings of reinnervation of the thenar muscle in five patients who underwent the contralateral C7 nerve root transfers for repair of total brachial plexus root avulsions.

Patients and methods:

Five (2 children and 3 adults) of 32 patients who received two‐staged procedures of the contralateral C7 nerve root transfers to the median nerves showed reinnervation of thenar muscle were evaluated. The patients also received other procedures including the intercostal nerve transfer to the musculocutaneous nerve, the spinal accessory nerve to the suprascapular nerve, and the ipsilateral phrenic nerve to the musculocutaneous nerve before the contralateral C7 nerve root transfers. The patients were followed up from 24 to 118 months after surgery.

Results:

Varied degrees of functional restorations were achieved after different procedures. The strength of abductor pollicis brevis (APB) muscle with Grade M2 was found in four patients. The incomplete interference pattern in the APB muscle was detected by electromyogram (EMG) in two patients, and the minority motor unit potential (MUP) was detected in other two patients. The strength of APB muscle was found with Grade M1 in one patient with EMG showing MUP.

Conclusion:

The findings from our series show reinnervation of thenar muscles after repair of the median nerve with the contralateral C7 nerve root transfer, which provides evidence for further investigation of reconstruction of the brachial plexus root avulsion injury with this procedure. © 2010 Wiley‐Liss, Inc. Microsurgery, 2011.
Repair of complete nerve lacerations at the forearm: An outcome study using Rosén–Lundborg protocol
Authors: Galanakos Spyridon P. , Zoubos Aristides B. , Ignatiadis Ioannis , Papakostas Ioannis , Gerostathopoulos Nikolaos E. , Soucacos Panayotis N.
Published: December 2010

A comparison of outcomes based on a scoring system for assessments, described by Rosén and Lundborg, after sharp complete laceration of median and/or ulnar nerves at various levels in the forearm was carried out. There were 66 males (90.4%) and 7 females (9.6%), with a mean age of 31 years (range: 14–62 years). The patients were categorized into three groups according to the type of nerve injury. The median nerve was injured in 25 cases (group M, 34.3%), the ulnar in 27 (group U, 36.9%), and both the nerves in 21 (group MU, 28.8%). The demographic data of the patients and the mechanism of injury were recorded. We also examined the employment status at the time of the injury and we estimated the percentage of patients who returned to their work after trauma. In all cases, a primary epineural repair was performed. Concomitant injuries were repaired in the same setting. The mean period of time between injury and surgery was 5.3 hours (range: 2–120 hours). A rehabilitation protocol and a reeducation program were followed in all cases. The mean follow‐up was 3 years (range: 2–6 years), with more distal injuries having a shorter follow‐up period. The total score was 2.71 in group M (range: 0.79–2.99) and 2.63 in group U (range: 0.63–3), with no significant differences observed. There was a significant difference between these two groups and group MU (total score 2.03, range: 0.49–2.76, P = 0.02). Up to the last follow‐up, 61 patients (83.5%) had returned to their previous work. The Rosén–Lundborg model can be a useful and simple tool for the evaluation of the functional outcome after nerve injury and repair temporally reflecting the processes of regeneration and reinnervation. © 2010 Wiley‐Liss, Inc. Microsurgery, 2011.
In vivo carotid plaque MRI using quantitative T2* measurements with ultrasmall superparamagnetic iron oxide particles: a dose–response study to statin therapy
Authors: Patterson Andrew J. , Tang Tjun Y. , Graves Martin J. , Müller Karin H. , Gillard Jonathan H.
Published: December 2010

This study investigates T2* quantification in carotid plaques before and after the administration of ultrasmall superparamagnetic iron oxide particles (USPIOs) in a cohort of patients receiving statin therapy. Phantom studies were performed using gels with varying concentrations of USPIOs. In the phantom study, 12 gels were prepared with a range of freely distributed concentrations of USPIO nanoparticles (0–0.05 mg/mL). Relative signal intensity measurements were obtained from a T2*‐weighted sequence as well as quantitative T2* (qT2*) measurements. In the patient study, 40 patients with >40% carotid stenosis were randomised to low‐ and high‐dose statin therapy (10 and 80 mg of atorvastatin). Pre‐ and post‐ (36 h) USPIO‐enhanced MRI were performed at baseline, and at 6 and 12 weeks. A linear mixed‐effects model was applied to account for the inherent correlation of multiple‐plaque measurements from the same patient and to assess dose–response differences to statin therapy. In the phantom study, the T2*‐weighted sequence demonstrated an initial increase (T1 effect), followed by a decrease (T2* effect), in relative signal intensity with increasing concentrations of USPIO. The qT2* values decreased exponentially with increasing concentrations of USPIO. In the patient study, there was a highly significant difference in post‐USPIO T2* measurements in plaques between the low‐ and high‐dose statin groups. This was observed for both the difference in qT2* measurements (post‐USPIO minus pre‐USPIO) (p < 0.001) and for qT2* post‐USPIO only (p < 0.001). The post‐USPIO qT2* values were as follows: baseline: low dose, 13.6 ± 5.5 ms; high dose, 12.9 ± 6.2 ms; 6 weeks: low dose, 13.3 ± 6.7 ms; high dose, 14.3 ± 7.7 ms; 12 weeks: low dose, 14.0 ± 7.6 ms; high dose, 18.3 ± 11.2 ms. It can be concluded that qT2* measurements provide an alternative method of quantifying USPIO uptake. These results also demonstrate that changes in USPIO uptake can be measured using post‐USPIO imaging only. Copyright © 2010 John Wiley & Sons, Ltd.
Blood oxygenation level‐dependent (BOLD) functional MRI of visual stimulation in the rat retina at 11.7 T
Authors: La Garza Bryan H. De , Muir Eric R. , Li Guang , Shih Yen‐Yu I. , Duong Timothy Q.
Published: December 2010

Although optically based imaging techniques provide valuable functional and physiological information of the retina, they are mostly limited to the probing of the retinal surface and require an unobstructed light path. MRI, in contrast, could offer physiological and functional data without depth limitation. Blood oxygenation level‐dependent functional MRI (BOLD fMRI) of the thin rat retina is, however, challenging because of the need for high spatial resolution, and the potential presence of eye movement and susceptibility artifacts. This study reports a novel application of high‐resolution (111 × 111 × 1000 µm3) BOLD fMRI of visual stimulation in the anesthetized rat retina at 11.7 T. A high‐field MRI scanner was utilized to improve the signal‐to‐noise ratio, spatial resolution and BOLD sensitivity. Visual stimuli (8 Hz diffuse achromatic light) robustly increased BOLD responses in the retina [5.0 ± 0.8% from activated pixels and 3.1 ± 1.1% from the whole‐retina region of interest (mean ± SD), n = 12 trials on six rats, p < 0.05 compared with baseline]. Some activated pixels were detected surrounding the pupil and ciliary muscle because of accommodation reflex to visual stimuli, and were reduced with atropine and phenylephrine eye drops. BOLD fMRI scans without visual stimulations showed no significantly activated pixels (whole‐retina BOLD changes were 0.08 ± 0.34%, n = 6 trials on five rats, not statistically different from baseline, p > 0.05). BOLD fMRI of visual stimulation has the potential to provide clinically relevant data to probe hemodynamic neurovascular coupling and dysfunction of the retina with depth resolution. Copyright © 2010 John Wiley & Sons, Ltd.
Functionalized carbon nanotube/polyacrylonitrile composite nanofibers: fabrication and properties
Authors: Wang Kaitao , Gu Mingbo , Wang Jian‐jun , Qin Chuanxiang , Dai Lixing
Published: December 2010

The functionalized multi‐walled carbon nanotubes (f‐MWCNTs) were obtained by Friedel–Crafts acylation, which introduced aromatic amine groups onto the sidewall. And the grafted yield was adjusted by controlling the concentration of the catalyst. The composite solutions containing f‐MWCNTs and polyacrylonitrile (PAN) were then prepared by in‐situ or ex‐situ solution polymerization. The resulting solutions were electrospun into composite nanofibers. In the in‐situ polymerization, morphological observation revealed that f‐MWCNTs was uniformly dispersed along the axes of the nanofibers and increased interfacial adhesion between f‐MWCNTs and PAN. Furthermore, two kinds of f‐MWCNTs/PAN composite nanofibers had a higher degree of crystallization and a larger crystal size than PAN nanofibers had, so the specific tensile strengths and modulus of the composite nanofibers were enhanced. And the thermal stability of f‐MWCNTs/PAN from in‐situ method was higher than that of ex‐situ system. When the f‐MWCNTs content was less than 1 wt%, the specific tensile strengths and modulus of nanofibers were enhanced with increase in the amounts of f‐MWCNTs, and f‐MWCNTs/PAN of in‐situ system provided better mechanical properties than that of ex‐situ system. Copyright © 2010 John Wiley & Sons, Ltd.