bluuebunny/crossref_metadata_2025 huggingface dataset:
Prospective multicenter clinical trial of immunosuppressive drug withdrawal in stable adult liver transplant recipients
Authors: Benítez Carlos , Londoño María-Carlota , Miquel Rosa , Manzia Tommaso-Maria , Abraldes Juan G. , Lozano Juan-José , Martínez-Llordella Marc , López Marta , Angelico Roberta , Bohne Felix , Sese Pilar , Daoud Frederic , Larcier Patrick , Roelen Dave L. , Claas Frans , Whitehouse Gavin , Lerut Jan , Pirenne Jacques , Rimola Antoni , Tisone Giuseppe , Sánchez-Fueyo Alberto
Published: March 2013

Lifelong immunosuppression increases morbidity and mortality in liver transplantation. Discontinuation of immunosuppressive drugs could lessen this burden, but the safety, applicability, and clinical outcomes of this strategy need to be carefully defined. We enrolled 102 stable liver recipients at least 3 years after transplantation in a single-arm multicenter immunosuppression withdrawal trial. Drugs were gradually discontinued over a 6 to 9-month period. The primary endpoint was the development of operational tolerance, defined as successful immunosuppressive drug cessation maintained for at least 12 months with stable graft function and no histopathologic evidence of rejection. Out of the 98 recipients evaluated, 57 rejected and 41 successfully discontinued all immunosuppressive drugs. In nontolerant recipients rejection episodes were mild and resolved over 5.6 months (two nontolerant patients still exhibited mild gradually improving cholestasis at the end of follow-up). In tolerant recipients no progressive clinically significant histological damage was apparent in follow-up protocol biopsies performed up to 3 years following drug withdrawal. Tolerance was independently associated with time since transplantation (odds ratio [OR] 1.353;

P

= 0.0001), recipient age (OR 1.073;

P

= 0.009), and male gender (OR 4.657;

P

= 0.016). A predictive model incorporating the first two clinical variables identified subgroups of recipients with very high (79%), intermediate (30%-38%), and very low (0%) likelihood of successful withdrawal.

Conclusion:

When conducted at late timepoints after transplantation, immunosuppression withdrawal is successful in a high proportion of carefully selected liver recipients. A combination of clinical parameters could be useful to predict the success of this strategy. Additional prospective studies are now needed to confirm these results and to validate clinically applicable diagnostic biomarkers. (Hepatology 2013;58:1824–1835)
Energy‐saving evaluation of a thermosyphon heat recovery unit for an air‐conditioning system
Authors: Ma Guoyuan , Zhou Feng , Liu Ting , Wang Liangbing , Liu Zhongliang
Published: March 2013

The energy‐saving effect and economic benefits of a thermosyphon heat recovery unit installed in a shopping mall are investigated. To evaluate the thermal performance of the heat recovery unit in a season, a seasonal temperature effectiveness is advanced, and its calculation formula is deduced referring to the calculation method of seasonal energy efficiency ratio (SEER) for an air conditioner. The annual operating energy‐saving effect of the unit is analyzed by using the seasonal temperature effectiveness while the static economic evaluation method is applied for the economic benefits analysis of the unit. The analysis results indicate the seasonal temperature effectiveness of the unit is 66.08% in the winter and 55.43% in the summer. The energy‐saving effect of the unit is quite remarkable, and the payback time is about 2.65 years. © 2013 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com/journal/htj). DOI 10.1002/htj.21049
Geologic and hydrologic settings for development of freshwater lenses in arid lands
Authors: Milewski Adam , Sultan Mohamed , Al‐Dousari Ahmad , Yan Eugene
Published: March 2013

Satellite observations were used to test the validity of previously identified favourable conditions for the formation of freshwater lenses, identify additional potential occurrences, and model modern potential recharge in the Raudhatain Watershed (3696) in northern Kuwait. Favourable conditions include infrequent yet intensive precipitation events, drainage depressions to collect the limited runoff, and presence of conditions (e.g. high infiltration capacity) that promote groundwater recharge and preservation (e.g. underlying saline aquifer) of infiltrating groundwater as freshwater lenses floating over saline aquifer water due to differences in density. Specifically, the following field and satellite‐based observations were noted for the Raudhatain Watershed: (1) Over ~30 precipitation events were identified from the Tropical Rainfall Measuring Mission precipitation data (1998–2009); (2) slope is gentle (2 m/km), and the surface is largely (80%) covered by alluvial deposits with high infiltration capacities (up to 9 m/day); (3) no flows and long‐term ponding were reported at the watershed outlet or detected from Landsat thematic mapper images; (4) infiltration is high based on increases in soil moisture content (from an advanced microwave scanning radiometer) and vegetation index following large precipitation events; and (5) freshwater lenses that overlie highly saline [total dissolved solids (TDS): >35 000] unconfined aquifers underlying the watershed are absent in the southern regions, where infiltrating fresh water mixes with the less saline groundwater (TDS: <10 000). Twenty potential locations (size: 1 to 75 km2) for freshwater lens development were identified in northern Kuwait, and continuous rainfall–runoff models (Soil Water and Assessment Tool) were applied to provide a first‐order estimation of the average annual recharge in the watershed (127 × 106 m3) and freshwater lenses (8.17 × 106 m3). Results demonstrate the settings for enhanced opportunities for groundwater recharge, outline the amounts of and preservation conditions for the groundwater feeding the freshwater lenses, and highlight potential applications and locations of freshwater lenses in similar settings elsewhere in the Arabian Peninsula and beyond. Copyright © 2013 John Wiley & Sons, Ltd.
A new longitudinal approach to assess hydrologic connectivity: Embanked floodplain inundation along the lower Mississippi River
Authors: Hudson P. F. , Sounny‐Slitine M. A. , LaFevor M.
Published: March 2013

Hydrologic connectivity is fundamental to understanding floodplain processes along meandering river corridors. This study contributes to understanding hydrologic connectivity by utilizing a high resolution Light Detection and Ranging DEM with a new GIS‐based approach for identifying the precise elevation of flood stage. The method created a high‐resolution longitudinal channel bank profile, enabling a detailed examination of embanked floodplain hydrologic connectivity. A simple channel cross‐section approach is likely to result in a large underestimation of floodplain inundation and hydrologic connectivity along meandering river floodplains because of differences in the elevation of the natural levee surface relative to floodplain bottoms and the considerable variability in the elevation of the channel bank profile. There is a large disparity in discharge duration associated with floodplain inundation in comparison to river channel bank inundation. A discharge duration of 10% is associated with inundation of 87% of the floodplain surface whereas only 53% of the channel bank profile is overtopped. An apparent threshold in inundation occurs as the discharge duration decreases below about 35%. While a duration of 25% results in very little of the channel bank being overtopped, it inundates 50% of the floodplain surface. Floodplain borrow pits, which are created in association with dike construction, represent a constant anthropogenic influence on the lower Mississippi embanked floodplain morphology, and are inundated by low discharge magnitudes. The results of the investigation shed new light on the topic of hydrologic connectivity for an important embanked fluvial system that has previously received little attention concerning its physical floodplain processes. Copyright © 2013 John Wiley & Sons, Ltd.
‘BIG DATA’, THE ‘INTERNET OF THINGS’ AND THE ‘INTERNET OF SIGNS’
Authors: O'Leary Daniel E.
Published: March 2013

This paper examines the relationship between so‐called ‘Big Data’, the ‘Internet of Things’ (the ‘Internet of People and Things,’ and the ‘Internet of Everything’), and the ‘Internet of Signs.’ In particular, we investigate how the ‘things’ in the ‘Internet of Things’ generate ‘Big Data’, and how both are used to generate semiotic ‘signs’. In addition, we analyse the importance of context in and the relationships between ‘Big Data’, the ‘Internet of Things’, and the ‘Internet of Signs’. Copyright © 2013 John Wiley & Sons, Ltd.
Helping High Schools Meet Higher Standards
Authors: Au Kathryn H.
Published: March 2013

Educational policy in the U.S. currently centers on college and career readiness, with the spotlight is on high schools to meet higher expectations for students’ literacy achievement. Ever‐rising expectations are consistent with the U.S. standards movement, now in its third iteration. As funding for school improvement becomes increasingly scarce, high schools must try to do more with less. A focused, disciplined approach to literacy improvement is recommended, based on three major actions. First, school leaders should build the infrastructure to support a multi‐year literacy improvement effort. Second, they should teach teachers to view each new standards document as an opportunity to examine and, when necessary, raise their expectations for students’ literacy learning. Language suggesting that teachers must adopt or comply with standards runs counter to this approach. Finally, leaders should have teachers take ownership of literacy improvement efforts through building their own staircase curricula.
Boys’ Hidden Literacies: The Critical Need for the Visual
Authors: Rowsell Jennifer , Kendrick Maureen
Published: March 2013

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Comparison of angiogenic potential between prevascular and non‐prevascular layered adipose‐derived stem cell‐sheets in early post‐transplanted period
Authors: Sasagawa Tadashi , Shimizu Tatsuya , Sekiya Sachiko , Yamato Masayuki , Okano Teruo
Published: March 2013

Layered adipose‐derived stem cell (ADSC) sheet transplantation is attracting attention as a new stem cell therapeutic strategy for damaged hearts. To prolong the function of tissue‐engineered constructs after transplantation, a rapid and sufficient vascularization of engrafted tissue is essential. The in vitro formation of network structures derived from endothelial cells (ECs) in grafts before transplantation contributes to the induction of functional anastomosis in vivo. This study compared the angiogenic potential of ADSC sheets containing dissociated ECs (non‐prevascular cell‐sheets) and networked ECs (prevascular cell‐sheets) after transplantation. For preparing the two different types of ECs‐containing layered cell‐sheets, human umbilical vein endothelial cells (HUVECs) were sandwiched between two human ADSC sheets. Non‐prevascular cell‐sheets were obtained immediately after sandwiching without further cultivation. Prevascular cell‐sheets were harvested form temperature‐responsive culture dishes following re‐cultivation for allowing them to form an EC network structure. In transplant experiments in the subcutaneous tissues of immune‐deficient rat for 4 days, prevascular cell‐sheets were observed to promote neovascularization with HUVEC‐lined microvessels. In contrast, neovessels were hardly observed in non‐prevascular cell‐sheets. These results suggested that prefabricated EC network in layered cell‐sheet was effective for making a rapid connection to the host vasculature in the early post‐transplanted period. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 358–365, 2014.
Preparation of chitosan/silk fibroin/hydroxyapatite porous scaffold and its characteristics in comparison to bi‐component scaffolds
Authors: Qi Xiao‐Ni , Mou Zhao‐Li , Zhang Jing , Zhang Zhi‐Qi
Published: March 2013

Composite porous scaffolds have attracted extensive attention in the biomedical material field. The aim of this research was to prepare a novel tri‐component composite porous scaffold and to evaluate its relevant properties. The porous scaffold was composed of chitosan (CS), silk fibroin (SF), and nanohydroxyapatite particles (nHA), which we named CS/SF/nHA scaffold and prepared via salt fractionation method combined with lyophilization. The porous structure was achieved using a porogen (salt), and the pore size was controlled by the size of porogen. To evaluate the characteristics of the tri‐component scaffold, three bi‐component scaffolds, CS/SF, CS/nHA, and SF/nHA, were simultaneously prepared for comparison. The scaffolds were subjected to morphological, micro‐structural, and biodegradation analyses. Results demonstrated that all of the scaffolds had pore sizes of 100–300 μm and a porosity of 90.5–96.1%. The biodegradation characteristics of all scaffolds meet the requirements of good biomedical materials. The investigation of the mechanical properties showed that the tri‐component scaffold has better properties than the bi‐component scaffolds. The in vitro biocompatibility with osteoblast‐like MG‐63 cells showed that all the scaffolds are suitable for cell attachment and proliferation; however, the CS/SF/nHA composite porous scaffold is much more effective than the others. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 366–372, 2014.
Electrospun nanofibers as a bioadhesive platform for capturing adherent leukemia cells
Authors: Cao Xue , Kwek Kenneth , Chan Jerry K. Y. , Chan Casey K. H. , Lim Mayasari
Published: March 2013

This study investigated the adhesive behaviors of normal and abnormal hematopoietic cells on nanotopographical materials. Previously, electrospun nanofiber scaffolds (NFSs) were used to capture and expand hematopoietic stem cells in vitro; here, we demonstrate that NFS could also serve as a useful bioadhesive platform for capturing functionally adherent leukemia cells. Collagen‐blended poly(d,l‐lactide‐co‐glycolide) NFS enabled more rapid and efficient capture of K562 leukemia cells than tissue culture polystyrene surfaces with up to 70% improved adhesion and shorter time. Cellular extensions, stronger adhesion, and enhanced cell–cell interactions were observed in K562 cells captured on NFS. While NFS promoted hematopoietic progenitor cell proliferation, it inhibited leukemia cell proliferation and affected cell cycle status by shifting more cells toward the G0/G1 phase. The expression of α‐integrins was equally high in both captured and uncaptured leukemia cell populations demonstrating no relation to its adhesive nature. Hematopoietic morphological signatures of NFS captured cells presented no impact on cell differentiation. We conclude that electrospun NFS serves as an excellent platform not only for capturing functionally adherent leukemia cells but also for studying the impact of niche‐like structure in the nanoscale. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 523–531, 2014.
Enhanced bioactivity and osteoconductivity of hydroxyapatite through chloride substitution
Authors: Cho Jung Sang , Yoo Dong Su , Chung Yong‐Chae , Rhee Sang‐Hoon
Published: March 2013

The effect of chloride‐substitution on bioactivity and osteoconductivity of hydroxyapatite (OHAp) was newly investigated. Chloride‐substituted hydroxyapatites (ClAp) with low and high chloride concentrations were synthesized by reacting Ca(OH)2 and H3PO4 with NH4Cl of low and high concentrations, with subsequent sintering. As a control, pure OHAp was prepared under the same conditions but without addition of NH4Cl. The ClAp showed markedly enhanced bioactivity in simulated body fluid (SBF) as the chloride substitution was increased. In contrast, OHAp did not show any bioactivity at all within the testing period. The solubility tests in deionized water also showed that the higher the chloride‐substituting amount, the higher the dissolution amounts of the constituent elements of apatite, which directly affect bioactivity by increasing the degree of supersaturation of apatite in SBF. In addition, ClAp also showed noticeably higher osteoconductivity within the 4 weeks of implantation in calvarial defects of New Zealand white rabbits, compared with that of OHAp. The total system energy of the apatite calculated by the ab initio method showed that the higher the chloride‐substituting amount, the higher the total system energy, which suggests that the ClAp was energetically less stable compared with OHAp. This result demonstrates the higher solubility of ClAp over that of OHAp in SBF and deionized water. The improved solubility of the OHAp enhances its bioactivity and consequent osteoconductivity. Taken together, it can be concluded that ClAp has encouraging potential for use as a bone grafting material due to its highly enhanced bioactivity and osteoconductivity compared with pure OHAp. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 455–469, 2014.
Dual antibacterial agents of nano‐silver and 12‐methacryloyloxydodecylpyridinium bromide in dental adhesive to inhibit caries
Authors: Zhang Ke , Li Fang , Imazato Satoshi , Cheng Lei , Liu Huaibing , Arola Dwayne D. , Bai Yuxing , Xu Hockin H. K.
Published: March 2013

Dental resins containing 12‐methacryloyloxydodecylpyridinium bromide (MDPB) showed potent antibacterial functions. Recent studies developed antibacterial resins containing nanoparticles of silver (NAg). The objectives of this study were to develop an adhesive containing dual agents of MDPB and NAg for the first time and to investigate the combined effects of antibacterial adhesive and primer on biofilm viability, metabolic activity, lactic acid, dentin bond strength, and fibroblast cytotoxicity. MDPB and NAg were incorporated into Scotchbond Multi‐Purpose (SBMP) adhesive “A” and primer “P”. Five systems were tested: SBMP adhesive A; A + MDPB; A+NAg; A + MDPB + NAg; P + MDPB + NAg together with A + MDPB + NAg. Dental plaque microcosm biofilms were cultured using mixed saliva from 10 donors. Metabolic activity, colony‐forming units, and lactic acid production of biofilms were investigated. Human fibroblast cytotoxicity of bonding agents was determined. MDPB + NAg in adhesive/primer did not compromise dentin bond strength (p > 0.1). MDPB or NAg alone in adhesive substantially reduced the biofilm activities. Dual agents MDPB + NAg in adhesive significantly reduced the biofilm viability compared with each agent alone (p < 0.05). The greatest inhibition of biofilms was achieved when both adhesive and primer contained MDPB + NAg. Fibroblast viability of groups with dual antibacterial agents was similar to control using culture medium without resin eluents (p > 0.1). In conclusion, this study showed for the first time that the antibacterial potency of MDPB adhesive could be substantially enhanced via NAg. Adding MDPB + NAg into both primer and adhesive achieved the strongest antibiofilm efficacy. The dual agent (MDPB + NAg) method could have wide applicability to other adhesives, sealants, cements, and composites to inhibit biofilms and caries. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2013.
In vitro biological response of plasma electrolytically oxidized and plasma‐sprayed hydroxyapatite coatings on Ti–6Al–4V alloy
Authors: Yeung Wing Kiu , Reilly Gwendolen C. , Matthews Allan , Yerokhin Aleksey
Published: March 2013

Plasma electrolytic oxidation (PEO) is a relatively new surface modification process that may be used as an alternative to plasma spraying methods to confer bioactivity to Ti alloy implants. The aim of this study was to compare physical, chemical and biological surface characteristics of two coatings applied by PEO processes, containing different calcium phosphate (CaP) and titanium dioxide phases, with a plasma‐sprayed hydroxyapatite (HA) coating. Coating characteristics were examined by X‐ray diffraction, energy dispersive X‐ray spectroscopy, scanning electron microscopy, surface profilometry, and wettability tests. The biological properties were determined using the human osteoblastic cell line MG‐63 to assess cell viability, calcium and collagen synthesis. The tests showed that PEO coatings are significantly more hydrophilic (6%) and have 78% lower surface roughness (Ra) than the plasma‐sprayed coatings. Cell behavior was demonstrated to be strongly dependent on the phase composition and surface distribution of elements in the PEO coating. MG‐63 viability for the TiO2‐based PEO coating containing amorphous CaPs was significantly lower than that for the PEO coating containing crystalline HA and the plasma‐sprayed coating. However, collagen synthesis on both the CaP and the TiO2 PEO coatings was significantly higher (92% and 71%, respectively) than on the plasma‐sprayed coating after 14 days. PEO has been demonstrated to be a promising method for coating of orthopedic implant surfaces. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2013.
Novel albendazole–chitosan nanoparticles for intestinal absorption enhancement and hepatic targeting improvement in rats
Authors: Liu Yang , Wang Xiao‐qing , Ren Wei‐xin , Chen Yuan‐lan , Yu Yang , Zhang Jian‐kang , Bawudong Dilimulati , Gu Jun‐peng , Xu Xiao‐dong , Zhang Xue‐nong
Published: March 2013

To improve the treatment of helminthiasis, filariasis, and colorectal cancer, albendazole‐associated chitosan nanoparticles (ABZ‐CS‐NPs) were prepared using the emulsion crosslinking volatile technique with contained sodium tripolyphosphate as the crosslinking agent and Poloxamer 188 as the auxiliary solvent. The structural characteristics of the NPs were determined using X‐ray diffraction to analyze the interaction between CS and the drug. The NPs were then evaluated in terms of their physicochemical characteristics, drug release behavior, in vivo pharmacokinetic parameters, and biodistribution in animal studies. ABZ‐loaded NPs with a uniformly spherical particle sizes (157.8 ± 2.82 nm) showed efficient drug loading, encapsulated efficiency, and high physical stability. The drug release from ABZ‐CS‐NPs was extended over several periods. Kinetic models were then fitted to determine the release mechanisms. ABZ and its metabolite albendazole sulfoxide (ABZSX) were analyzed in rats with mebendazole as the internal standard using reversed‐phase high‐performance liquid chromatography. Compared with the ABZ suspension groups, the relative bioavailability values of ABZ and ABZSX were 146.05 and 222.15%, respectively. In addition, the plasma concentration versus time curve is consistent with that of the two compartment models in the plasma concentration versus time curve. The results indicate that the ABZ‐loaded NPs are promising novel ABZ candidates for passive diffusion in the treatment of hydatid cysts in the liver via oral administration. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Evaluation of industrial wastes as sources of fertilizer silicon using chemical extractions and plant uptake
Authors: Haynes Richard J. , Belyaeva O. N. , Kingston G.
Published: March 2013

Six inorganic industrial‐waste materials (coal fly ash, bauxite‐processing mud, steel slag, two samples of air‐cooled blast furnace [BF] slag, and one sample of water‐cooled BF slag), along with wollastonite, were evaluated as fertilizer‐Si sources. Evaluation was carried out by analyzing total and extractable Si fractions in the materials, by incubating them at two rates with a Si‐deficient soil and measuring potentially available extractable Si and by measuring yield and Si uptake by two successive rice crops grown in the fertilized soils. Of the waste materials used, fly ash had the highest total Si content (29%) but a negligible quantity was present in extractable forms. Steel slag and bauxite‐processing mud had only 5%–7% Si content while BF slags contained 14%–18% Si. All materials, other than fly ash, increased the amount of extractable Si present in the soil. Additions of steel slag and bauxite‐processing mud caused greater increases in Si extractability than the air‐cooled BF slags while water‐cooled BF slag–treated soils contained notably high acid‐extractable Si. Because of the alkaline nature of the materials, and their reaction products, there was a positive relationship between extractable soil Si and soil pH. However, an equilibration experiment using NaSiO3 as the Si source confirmed that Si solubility in the soil decreased with increasing pH. Dry‐matter yields of rice, at the lower rate of Si addition, were increased by all treatments other than fly ash. The higher rates of steel slag and bauxite‐processing mud caused yield depressions. Total Si uptake by rice was increased by all treatments, other than fly ash, and was greater at the higher rate of Si addition. It was concluded that the BF slags are the most effective waste materials as fertilizer‐Si sources and that, in slag‐amended soils, CaCl2 and NH4 acetate are the most reliable soil‐test extractants.
Perspectives on the Regional Economic Value of a Pilgrimage
Authors: Saayman Andrea , Saayman Melville , Gyekye Agyapong
Published: March 2013

Pilgrimages around the world attract large numbers of followers, often classified as religious tourists. More than a million people attend the annual Easter weekend meeting of The Zion Christian Church in the Limpopo Province of South Africa. It is one of the largest pilgrimages in the world and could be expected to have a significant impact on the regional economy. The aim of this paper is to shed light on the spending behaviour of pilgrims at the gathering and the impact that the event has on the economy of Limpopo – one of the poorest provinces in South Africa. Copyright © 2013 John Wiley & Sons, Ltd.
Experimental and Kinetic Modeling Study of Methanol Ignition and Oxidation at High Pressure
Authors: Aranda V. , Christensen J. M. , Alzueta M. U. , Glarborg P. , Gersen S. , Gao Y. , Marshall P.
Published: March 2013

A detailed chemical kinetic model for oxidation of CH3OH at high pressure and intermediate temperatures has been developed and validated experimentally. Ab initio calculations and Rice–Ramsperger–Kassel–Marcus/transition state theory (RRKM/TST) analysis were used to obtain rate coefficients for , , , and . The experiments, involving CH3OH/O2 mixtures diluted in N2, were carried out in a high‐pressure flow reactor at 600–900 K and 20–100 bar, varying the reaction stoichiometry from very lean to fuel‐rich conditions. Under the conditions studied, the onset temperature for methanol oxidation was not dependent on the stoichiometry, whereas increasing pressure shifted the ignition temperature toward lower values. Model predictions of the present experimental results, as well as rapid compression machine data from the literature, were generally satisfactory. The governing reaction pathways have been outlined based on calculations with the kinetic model. Unlike what has been observed for unsaturated hydrocarbons, the oxidation pathways for CH3OH under the investigated conditions were very similar to those prevailing at higher temperatures and lower pressures. At the high pressures, the modeling predictions for onset of reaction were particularly sensitive to the reaction.
Approximate Analytical Expressions for the Steady‐State Concentration of Substrate and Cosubstrate over Amperometric Biosensors for Different Enzyme Kinetics
Authors: Rasi M. , Indira K. , Rajendran L.
Published: March 2013

Mathematical models of amperometric biosensors at three basic types of enzyme kinetics in nonstationary diffusion conditions are discussed. The models are based on nonstationary diffusion equations containing a linear term related to the first‐order and nonlinear term related to the Michaelis–Menten and ping–pong of the enzymatic reaction mechanism. In this paper, we obtain approximate closed‐form analytical solutions for the nonlinear equations under steady‐state condition by using the homotopy analysis method. Analytical expressions for concentrations of substrate and cosubstrate and corresponding current response have been derived for all possible values of parameters. Furthermore, in this work, the numerical simulation of the problem is also reported using Scilab/MATLAB program. An agreement between analytical and numerical results is noted.
Characterization and Minimization of Block Copolypeptide Vesicle Cytotoxicity Using Different Hydrophobic Chain Lengths
Authors: Choe Uh‐Joo , Rodriguez April R. , Li Zhibo , Boyarskiy Sergey , Deming Timothy J. , Kamei Daniel T.
Published: March 2013

The previously reported amphiphilic block copolypeptide, poly(l‐lysine)60‐block‐poly(l‐leucine)20 (K60L20), is able to form vesicles that can be manipulated to different sizes and be prepared in large quantities. This study expands upon that work by varying the length of the hydrophobic segment to optimize the vesicles so that they are monodisperse and low in toxicity. Copolypeptides with longer oligoleucine segments are found to have fewer toxic micelles, small aggregates, and unstable vesicles, and exhibit lower toxicity than vesicles formed from copolypeptides with shorter hydrophobic domains. Oligoleucine segments that are too long, however, result in rigid hydrophobic membranes that prevent the vesicular assemblies from being extruded into a monodisperse population of nanoscale vesicles.

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Efficient numerical tool for the analysis and design of reflectarrays based on cells with three parallel dipoles
Authors: Florencio Rafael , Boix Rafael R. , Carrasco Eduardo , Encinar José A. , Losada Vicente
Published: March 2013

In this article, the Method of Moments in the spectral domain (MoM‐SD) is applied to the analysis of multilayered periodic structures, containing three coplanar parallel dipoles in the unit cell. It is shown that the use of basis functions with edge singularities in the modeling of the current density on the dipoles leads to important computer memory and CPU times savings in the analysis of the periodic structures. The MoM‐SD home‐made software is used in the analysis of a shaped beam reflectarray antenna made of cells with three parallel dipoles under the local periodicity assumption. The numerical results obtained for the radiation pattern of the antenna are compared with numerical results provided by the commercial software CST® and with measurements and good agreement is found. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1212–1216, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27533
A power efficient active integrated antenna
Authors: Lee Joungyoung , Wu Chung‐Tse Michael , Itoh Tatsuo
Published: March 2013

We have integrated a microwave oscillator with a zeroth‐order resonance antenna to build an active oscillating antenna using the coplanar waveguide technology. In this design, the antenna is electrically small and the oscillator has an excellent phase noise performance of 92.5 dBc/Hz. Also, 16.11 dBm (40.83 mW) of effective isotropic radiated power is radiated with high direct current to radio frequency efficiency (27.2%), which is much higher than many other active oscillating antenna designs. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1240–1243, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27543
Radar cross section (RCS) statistical characterization using weibull distribution
Authors: Shi Weiqiang , Shi Xiao‐Wei , Xu Le
Published: March 2013

Radar target's backscatter varies rapidly because of change in the relative position of each scatterer, body vibration while moving and so on. Weibull distribution is adopted as an inclusive description of the envelope of various targets' backscattering in this paper. Weibull distribution is expressed as a function of two parameters, shape parameter and scale parameter. The parametric meanings are discussed with the distribution curves of different parameter values plotted. The authors find that Weibull distribution with a proper shape parameter can be an impressively good approximation of some existing RCS distribution models. A parameter estimation method is provided. Two examples are shown to illustrate the application of Weibull distribution. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1355–1358, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27557
DC‐bias and oscillation‐amplitude dependent frequency‐tuning characteristics of varactor‐switching dual‐band CMOS VCOs
Authors: Jang Sheng‐Lyang , Jain Sanjeev , Huang Jhin‐Fang , Hsue Ching‐Wen
Published: March 2013

This article studies the bias and oscillation‐amplitude dependent RF tuning property of varactor‐switching dual‐band voltage‐controlled oscillators (VCOs). The dual‐resonance LC‐tank n‐core and p‐core VCOs have been fabricated using 0.18 μm CMOS technology, and they use dual‐resonance LC resonator consisted of a parallel‐tuned LC resonator and a series resonant resonator. The accumulation‐mode MOS varactors are used. The RF circuit parameters such as oscillation frequency, tuning range, and transition frequency between low‐band and high band as a function of varactor bias, supply voltage, and oscillation amplitude are examined experimentally. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1389–1393, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27574
Peripheral Neuropathy: Assessment of Proximal Nerve Integrity By Diffusion Tensor Imaging
Authors: Mathys Christian , Aissa Joel , Zu Hörste Gerd Meyer , Reichelt Dorothea C. , Antoch Gerald , Turowski Bernd , Hartung Hans‐Peter , Sheikh Kazim A. , Lehmann Helmar C.
Published: March 2013

Introduction: We investigated the utility of diffusion tensor imaging (DTI) for detecting neuropathic changes in proximal nerve segments in patients with peripheral neuropathy. Methods: Twenty‐one individuals with (n = 11) and without (n = 10) peripheral neuropathy underwent DTI of a defined sciatic nerve segment. Patients and controls were evaluated by clinical examination and nerve conduction studies at baseline and 6 months after the initial DTI scan. Results: The mean fractional anisotropy (FA) value was significantly lower in sciatic nerves from patients with peripheral neuropathy as compared with controls. Sciatic nerve FA values correlated with clinical disability scores and electrophysiological parameters of axonal damage at baseline and 6 months after MRI scan. Conclusions: DTI‐derived FA values are a sensitive measure to discriminate healthy from functionally impaired human sciatic nerve segments. DTI of proximal nerve segments may be useful for estimating the proximal axonal degeneration burden in patients with peripheral neuropathies. Muscle Nerve 48: 889–896, 2013
High‐order iterative bracketing methods
Authors: Fried Isaac
Published: March 2013

This paper presents high‐order, single‐point, iterative methods for the numerical solution of the general non‐linear equilibrium equation. The methods are designed so that the approximations provided by the iterative process alternate about the targeted root, thus providing progressively better upper, as well as lower bounds on the sought root, which is thus numerically bracketed ever tighter. The effectiveness of the proposed methods is demonstrated by applying them to obtain close bounds on the extreme eigenvalues of the finite elements global stiffness matrix of the hanging string. Copyright © 2013 John Wiley & Sons, Ltd.
Beta and alpha cell function in metabolically healthy but obese subjects: Relationship with entero‐insular axis
Authors: Calanna Salvatore , Piro Salvatore , Di Pino Antonino , Maria Zagami Rose , Urbano Francesca , Purrello Francesco , Maria Rabuazzo Agata
Published: March 2013

Objective:

Obesity is widely acknowledged as a critical risk factor for metabolic complications. Among obese subjects, there is a phenotype of metabolically healthy but obese (MHO) individuals that shows a favorable cardiometabolic risk profile. We aimed to evaluate the potential mechanisms underlying the metabolic profile of this subset, including alpha and beta cell function and entero‐insular axis.

Design and Methods:

One hundred twenty‐nine obese and 24 nonobese subjects were studied. Obese participants were defined as MHO or at‐risk obese, according to the homeostasis model of assessment‐insulin resistance (HOMA‐IR) index (MHO: lower tertile of HOMA‐IR, n = 43; at‐risk: upper tertile of HOMA‐IR index, n = 41). Insulin, glucagon, and incretin responses after a 120′ oral glucose tolerance test (75‐g OGTT) were investigated.

Results:

During OGTT, MHO individuals showed in comparison with at‐risk subjects: lower fasting and afterloads plasma levels of glucose, insulin, and C‐peptide; higher disposition index; lower fasting (P = 0.004) and at 30′ (P = 0.01) plasma glucose‐dependent insulinotropic polypeptide (GIP) levels; lower area under the curve (AUC) (0‐30) for GIP (P = 0.008); higher glucagon‐like peptide‐1 (GLP‐1) plasma levels at 90′ (P = 0.02) and 120′ (P = 0.02); lower glucagon plasma levels at baseline (P = 0.04) and at 30′ (P = 0.03); and appropriate glucagon suppression after the oral glucose load.

Conclusions:

MHO subjects show, as well as normal‐weight individuals, a lower diabetogenic profile by virtue of higher disposition index and unaffected entero‐insular axis. At‐risk obese individuals present increased GIP levels that might play a role in determining increased glucagon secretion and inappropriate glucagon responses after glucose load, thus contributing to impaired glucose homeostasis.
The relationship of C‐reactive protein to obesity‐related depressive symptoms: A longitudinal study
Authors: Daly Michael
Published: March 2013

Objective:

Obesity has been shown to produce a state of systematic low‐grade inflammation that may have detrimental neuropsychiatric effects.

Design and Methods:

Longitudinal associations between obesity, inflammation, and depressive symptoms amongst a cohort of older English adults over 4 years of follow‐up were examined. Participants were 3,891 obese and nonobese people drawn from the English longitudinal study of ageing (ELSA) [aged 64.9 (SD = 8.8) years, 44.6% men]. Depressive symptoms were assessed at baseline and after 4 years of follow‐up using the eight‐item center for epidemiological studies—depression scale (CES‐D).

Results:

Approximately 26.3% (N = 1,025) of the sample were categorized as obese at baseline. Obesity at baseline was associated with elevated levels of depressive symptoms at follow‐up (P < 0.001), in analyses that adjusted for depression levels at baseline and sociodemographic and background variables including the prevalence of permanent illness/disability, alcohol consumption, sedentary behavior, and smoking. In addition, C‐reactive protein (CRP) concentrations at baseline were independently associated with CES‐D depression scores at follow‐up (P = 0.008) in fully adjusted analyses. Subsequent mediation analyses revealed that CRP levels explained ∼20% of the obesity‐related longitudinal change in depression scores.

Conclusion:

These data suggest that chronic inflammation may be a key determinant of depressive symptoms in obesity.
Family‐based hip‐hop to health: Outcome results
Authors: Fitzgibbon Marian L. , Stolley Melinda R. , Schiffer Linda , Kong Angela , Braunschweig Carol L. , Gomez‐Perez Sandra L. , Odoms‐Young Angela , Van Horn Linda , Christoffel Katherine Kaufer , Dyer Alan R.
Published: March 2013

Objective:

This pilot study tested the feasibility of Family‐Based Hip‐Hop to Health, a school‐based obesity prevention intervention for 3–5‐year‐old Latino children and their parents, and estimated its effectiveness in producing smaller average changes in BMI at 1‐year follow‐up.

Design and Methods:

Four Head Start preschools administered through the Chicago Public Schools were randomly assigned to receive a Family‐Based Intervention (FBI) or a General Health Intervention (GHI).

Results:

Parents signed consent forms for 147 of the 157 children enrolled. Both the school‐based and family‐based components of the intervention were feasible, but attendance for the parent intervention sessions was low. Contrary to expectations, a downtrend in BMI Z‐score was observed in both the intervention and control groups.

Conclusions:

While the data reflect a downward trend in obesity among these young Hispanic children, obesity rates remained higher at 1‐year follow‐up (15%) than those reported by the National Health and Nutrition Examination Survey (2009–2010) for 2–5‐year‐old children (12.1%). Developing evidence‐based strategies for obesity prevention among Hispanic families remains a challenge.
International Research Partnerships in Occupational Therapy: A Canadian–Zambian Case Study
Authors: Njelesani Janet , Stevens Marianne , Cleaver Shaun , Mwambwa Lombe , Nixon Stephanie
Published: March 2013

The country of Zambia's Sixth National Development Plan includes many objectives related to participation and health that align with values underlying occupational therapy. Given this link, occupational therapy research has the potential to advance the Sixth National Development Plan and thereby enhance the participation and health of Zambians. However, there is neither a school of occupational therapy nor many occupational therapists working in Zambia. Using an example of a global research partnership between Canadian occupational therapy researchers and Zambian researchers, this paper examines the partnership using four criteria for global health research in order to derive lessons for future occupational therapy research partnerships. Implications for future occupational therapy research partnerships include the need for partners to combine their complementary skills and knowledge so that they may collaborate in mutually beneficial ways to address global health challenges and expand the reach of occupational therapy perspectives. Copyright © 2013 John Wiley & Sons, Ltd.
Effect of novel copolyamide charring agents on flame‐retarded polypropylene
Authors: Yang Bin , Liu Heng , He Bobing , Leng Jinhua , Chen Xian
Published: March 2013

In this article, two novel copolyamide charring agents, ES‐6 and M‐170, were served as charring agents or synergist with ammonium polyphosphate (APP) and dipentaerythritol (DPER) for the flame‐retarded polypropylene (PP). The flame‐retardant system was characterized by limiting oxygen index (LOI), tensile strength, Izod impact strength, thermogravimetric analyses, differential scanning calorimeter (DSC), and scanning electron microscope (SEM). Compared with polyamide 6 (PA6), ES‐6 and M‐170 had better dispersion and compatibility in the PP matrix and enhanced mechanical properties. Meanwhile, as low melting point polyamides, ES‐6 and M‐170 could decrease processing temperature and effectively inhibit side reaction, especially the degradation of APP. In addition, the synergistic effect between ES‐6 and DPER was also investigated. The results showed that the synergistic system containing ES‐6 had better flame retardancy and mechanical performance in comparison with the system only using DPER or the system containing PA6. POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers
Surface‐grafting of ground rubber tire by poly acrylic acid via self‐initiated free radical polymerization and composites with epoxy thereof
Authors: Yagneswaran Sriram , Storer William J. , Tomar Neetu , Chaur Manuel N. , Echegoyen Luis , Smith Dennis W.
Published: March 2013

Commercially available recycled ground rubber tire (GRT) particles, found to contain persistent mechano‐free radicals confirmed by electron paramagnetic spectroscopy for the first time self‐initiates free radical polymerization of acrylic acid (AA). The poly acrylic acid (PAA) grafted GRT (PAA‐g‐GRT) was confirmed by Attenuated Total Reflection Fourier Transform Infrared spectroscopy, X‐ray photoelectron spectroscopy, and thermogravimetric analysis (TGA). Epoxy composites using the PAA‐g‐GRT as filler were prepared and their mechanical properties were studied. The PAA‐g‐GRT/epoxy composite showed higher mechanical properties with an increase of modulus up to 180% as compared with the neat GRT/epoxy composite. Surface morphology of GRT, neat GRT/epoxy, and PAA‐g‐GRT/epoxy composites were analyzed by scanning electron microscopy. This technology introduces a new concept to functional and reactive recycling and the cost effective utilization of renewable resource green materials. POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers
Discordant results between fetal karyotyping and non‐invasive prenatal testing by maternal plasma sequencing in a case of uniparental disomy 21 due to trisomic rescue
Authors: Pan Min , Li Fa Tao , Li Yan , Jiang Fu Man , Li Dong Zhi , Lau Tze Kin , Liao Can
Published: March 2013

Uniparental disomy (UPD) is an uncommon chromosome condition, but UPD involving chromosome 21 is rarely reported. We reported here a case who had first trimester screening test for Down syndrome, chorionic villus sampling for fetal karyotyping, quantitative fluorescence polymerase chain reaction (QF‐PCR), as well as non‐invasive prenatal testing (NIPT) by maternal plasma sequencing. There were discordant results between fetal karyotyping and NIPT due to UPD 21combined with confined placental mosaicism of trisomy 21. This demonstrated that it is possible to detect placental mosaicism by NIPT, but further studies are required to confirm its sensitivity. Therefore, all positive NIPT results must be confirmed by conventional invasive test and karyotyping. QF‐PCR has the additional benefit in diagnosing UPD. © 2013 John Wiley & Sons, Ltd.
In‐depth proteomic analyses of exosomes isolated from expressed prostatic secretions in urine
Authors: Principe Simona , Jones E. Ellen , Kim Yunee , Sinha Ankit , Nyalwidhe Julius O. , Brooks Jasmin , Semmes O. John , Troyer Dean A. , Lance Raymond S. , Kislinger Thomas , Drake Richard R.
Published: March 2013

Expressed prostatic secretions (EPS) are proximal fluids of the prostate that are increasingly being utilized as a clinical source for diagnostic and prognostic assays for prostate cancer (PCa). These fluids contain an abundant amount of microvesicles reflecting the secretory function of the prostate gland, and their protein composition remains poorly defined in relation to PCa. Using expressed prostatic secretions in urine (EPS‐urine), exosome preparations were characterized by a shotgun proteomics procedure. In pooled EPS‐urine exosome samples, ∼900 proteins were detected. Many of these have not been previously observed in the soluble proteome of EPS generated by our labs or other related exosome proteomes. We performed systematic comparisons of our data against previously published, prostate‐related proteomes, and global annotation analyses to highlight functional processes within the proteome of EPS‐urine derived exosomes. The acquired proteomic data have been deposited to the Tranche repository and will lay the foundation for more extensive investigations of PCa derived exosomes in the context of biomarker discovery and cancer biology.