bluuebunny/crossref_metadata_2025 huggingface dataset:
Liquid membrane technology: fundamentals and review of its applications
Authors: San Román M. F. , Bringas E. , Ibañez R. , Ortiz I.
Published: August 2009

OVERVIEW: During the past two decades, liquid membrane technology has grown into an accepted unit operation for a wide variety of separations. The increase in the use of this technology owing to strict environmental regulations and legislation together with the wider acceptance of this technology in preference to conventional separation processes has led to a spectacular advance in membrane development, module configurations, applications, etc.

IMPACT: Liquid membrane technology makes it possible to attain high selectivity as well as efficient use of energy and material relative to many other separation systems. However, in spite of the known advantages of liquid membranes, there are very few examples of industrial applications because of the problems associated with the stability of the liquid membrane.

APPLICATIONS: Liquid membrane technology has found applications in the fields of chemical and pharmaceutical technology, biotechnology, food processing and environmental engineering. On the other hand, its use in other fields, such as in the case of hydrogen separation, the recovery of aroma compounds from fruits, the application of ionic liquids in the membrane formulation, etc., is increasing rapidly. Copyright © 2009 Society of Chemical Industry
Effect of HBT on the stability of laccase during the decolourization of textile wastewaters
Authors: Khlifi Rim , Sayadi Sami , Belbahri Lassaad , Woodward Steve , Mechichi Tahar
Published: August 2009

BACKGROUND: This study concerns the assessment of laccase stability during textile industry effluent treatment by laccase in the presence of a mediator

RESULTS: The effects of 1‐hydroxybenzotriazole (HBT) and textile wastewater on the stability of a crude laccase prepared from cultures of Trametes trogii during the process of textile industry effluent decolourization were determined. HBT was essential for decolourization of effluent by laccase. Decolourization efficiency decreased when effluent was repeatedly added to the reaction mixture, suggesting inhibition of laccase during the process. Stability of the laccase was not affected by different concentrations of effluent, but inactivation was proportional to HBT concentration.

CONCLUSION: Experimental results showed that a redox mediator such as HBT was required for high decolourization rate of textile industry effluent; however free radicals generated from this compound inactivated the laccase used in the process. Copyright © 2009 Society of Chemical Industry
Use of engineered Escherichia coli cells to detect estrogenicity in everyday consumer products
Authors: Gawrys Michelle D. , Hartman Izabela , Landweber Laura F. , Wood David W.
Published: August 2009

BACKGROUND: Estrogenic activity has been observed in several industrial and household products, and some evidence suggests that this activity may be linked to increased pathologies in humans and animals. Here, an engineered strain of Escherichia coli is evaluated for its ability to detect estrogenic activity in complex mixtures, including natural dietary supplements, hand and body washes, essential oils, and perfumes. The engineered E. coli biosensor strain expresses the ligand‐binding domain of the human estrogen receptor β (ERβ) as part of a larger allosteric reporter enzyme. The result is a simple bacterial growth assay, where estrogenic activity of a test compound is reflected by increased cell growth on a simple defined medium.

RESULTS: While most consumer products did not yield a strong estrogenic response in the assay, a consistent estrogenic effect was observed with several perfumes. This effect is probably due to the presence of the known estrogen, benzophenone‐2, which exhibited an EC50 concentration of 0.44 µmol L−1 for the sensor strains used.

CONCLUSIONS: This simple, bacterial biosensor is capable of rapidly and inexpensively detecting estrogenic activity in complex consumer products, and may eventually yield rough estimates of the equivalent estrogen doses associated with their use. Copyright © 2009 Society of Chemical Industry
Effect of urea surface modification and photocatalytic cleaning on surface‐assisted laser desorption ionization mass spectrometry with amorphous TiO2 nanoparticles
Authors: Watanabe Takehiro , Okumura Koji , Kawasaki Hideya , Arakawa Ryuichi
Published: August 2009

We have investigated the effect of urea surface modification and the photocatalytic cleaning on surface‐assisted laser desorption ionization mass spectrometry (SALDI‐MS) with amorphous TiO2 nanoparticles for the reduction of the background noise and the improvement of the sensitivity. In the use of nanoparticles of high surface area, chemical background signals arising from ambient environments and organic contaminants can frequently be serious problems below 500 Da, possibly reducing the advantages of the matrix‐free approach. In this study, removal of contaminants and enhanced SALDI efficiency were easily achieved with UV irradiation via the photocatalyst effect of TiO2 before SALDI‐MS measurements. The surface cleaning achieved by the UV photocatalytic procedure reduced the background noise and increased the peak intensities of peptides. In addition, we found that urea surface modification of TiO2 nanoparticles increased the performance of the TiO2‐SALDI‐MS. (1) The urea‐surface modification of TiO2 made it possible to produce proton‐adduct forms without citrate buffer, resulting in low background noises below 500 Da, in contrast to the essential use of a citrate buffer in the bare TiO2‐SALDI‐MS. (2) The detection sensitivity of angiotensin I increased to 0.3 fmol with the urea‐surface modification, as compared to the use of bare TiO2 nanoparticles (6 fmol). The urea‐TiO2 could ionize proteins of more than 20 000 Da such as trypsinogen (600 fmol). (3) The urea modification of TiO2 had the advantage of selective detection of phosphopeptides without sample clean up, or prefractionation in tryptic digest products of bovine hemoglobin. Copyright © 2009 John Wiley & Sons, Ltd.
A tetrahedral tip as a probe for tip‐enhanced Raman scattering and as a near‐field Raman probe
Authors: Bortchagovsky Eugene G. , Fischer Ulrich C.
Published: August 2009

We use a tetrahedral glass fragment which is coated with a thin film of gold (T‐tip) to form a local tip source by illuminating the tip from within its transparent glass body. We demonstrate the potential of this apertureless tip source for tip‐enhanced Raman scattering (TERS) as an alternative to the standard scheme with an external illumination. We found that T‐tips with different optical properties result from the process of tip fabrication. For some tips, the Raman signal persists for a small number of molecules picked up by the retraction of the tip from a tunnel contact. In these cases, the tip itself gives rise to the TERS signal without a gold substrate close to the tip. Other tips only exhibit a TERS signal when there is a contact to a gold substrate. Tips covered by Raman active nonresonant molecules serve as a new kind of near‐field Raman probe for local properties of a sample. As the Raman spectrum of the coated tip is sensitive to the local light intensity, it may be used to monitor the field‐enhancement properties of metal films and metal nanostructures. A near‐field Raman probe avoids problems due to bleaching of a fluorescent near‐field probe and, furthermore, such a near‐field Raman probe may be highly selective for specific surface properties. Copyright © 2009 John Wiley & Sons, Ltd.
Elemental content and nutritional study of blood orange juice
Authors: Cautela Domenico , Santelli Francesca , Boscaino Floriana , Laratta Bruna , Servillo Luigi , Castaldo Domenico
Published: August 2009

BACKGROUND: The elemental content of Sicilian red orange juices and the bioaccessibility of many elements of particular nutritional interest was evaluated.

RESULTS: The elemental content of fresh juices from Sicilian blood oranges was analysed by ICP–OES, GF AAS, HG–AAS and CV AAS. Among the macroelements (Na, Ca, K, Mg and P), potassium occurred in the greatest amount, with 3.64% of the requested RDA for 100 mL of juice daily intake. The values of RDA 100 mL−1 of juice for Mg, P, Ca and Na resulted 1.61%, 1.26%, 0.59% and 0.09% respectively. For the trace elements Cr, Cu and Se, the RDA 100 mL−1 of juice were 9.20%, 7.14% and 1.82%, respectively.

In vitro tests simulating the digestive process showed high bioaccessibility only for boron and manganese while that of copper, zinc and iron were consistently lower.

CONCLUSIONS: Sicilian blood orange juices gave different results from non‐pigmented orange juices in terms of a higher content of copper, boron and lower content of chromium and manganese. However, among the nutritionally important elements, only manganese showed high bioaccessibility. The low bioaccessibility found for iron, zinc and copper is likely due to the presence in the orange juice of ligands such as polyphenols and organic acids. Copyright © 2009 Society of Chemical Industry
The Development of Genipin‐Crosslinked Poly(caprolactone) (PCL)/Gelatin Nanofibers for Tissue Engineering Applications
Authors: Kim Min Sup , Jun Indong , Shin Young Min , Jang Wonhee , Kim Sun I. , Shin Heungsoo
Published: August 2009

Composite nanofibers of poly(caprolactone) (PCL) and gelatin crosslinked with genipin are prepared. The contact angles and mechanical properties of crosslinked PCL‐gelatin nanofibers decrease as the gelatin content increases. The proliferation of myoblasts is higher in the crosslinked PCL‐gelatin nanofibers than in the PCL nanofibers, and the formation of myotubes is only observed on the crosslinked PCL‐gelatin nanofibers. The expression level of myogenin, myosin heavy chain, and troponin T genes is increased as the gelatin content is increased. The results suggest that PCL‐gelatin nanofibers crosslinked with genipin can be used as a substrate to modulate proliferation and differentiation of myoblasts, presenting potential applications in muscle tissue engineering.

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Control of Osteogenic Differentiation and Mineralization of Human Mesenchymal Stem Cells on Composite Nanofibers Containing Poly[lactic‐co‐(glycolic acid)] and Hydroxyapatite
Authors: Lee Ji Hye , Rim Nae Gyune , Jung Hyun Suk , Shin Heungsoo
Published: August 2009

We fabricated composite fibrous scaffolds from blends of poly(lactide‐co‐glycolide) (PLGA) and nano‐sized hydroxyapatite (HA) via electrospinning. SEM‐EDX and AFM analysis demonstrated that HA was homogeneously dispersed in the nanofibers, and the roughness increased along with the amount of incorporated HA. When hMSCs were cultured on these PLGA/HA composite nanofibers, we found that incorporation of HA on the nanofibers did not affect cell viability whereas increased ALP activity and expression of osteogenic genes as well as the calcium mineralization of hMSCs. Our results indicate that the composite nanofibers can be offered as a potential bone regenerative biomaterial for stem cell based therapies.

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Synthesis and Properties of Novel Biodegradable/Biocompatible Poly[propylene‐co‐(ethylene succinate)] Random Copolyesters
Authors: Papageorgiou George Z. , Bikiaris Dimitrios N.
Published: August 2009

Random biocompatible/biodegradable poly[propylene‐co‐(ethylene succinate)]s were prepared. Mechanical properties and crystallization rates decreased with propylene succinate content. Glass transition temperatures (Tg) varied between those for the homopolymers. DSC and TMDSC findings showed that multiple melting behaviour of PPESu samples is related to melting–recrystallization–remelting. WAXD observations, eutectic behaviour, and thermodynamic analysis of the equilibrium melting point depression indicated isodimorphic cocrystallization. The copolymers showed enzymatic hydrolysis rates between those of the homopolymers and cytotoxicity/biocompatibility similar to PLA.

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Tailoring of Low Bandgap Polymer and its Performance Analysis in Organic Solar Cells
Authors: Janietz Silvia , Krueger Hartmut , Schleiermacher Hans‐Frieder , Würfel Uli , Niggemann Michael
Published: August 2009

New conjugated, alternating ter‐polyfluorene prepared by Suzuki reaction and a LUMO energy level of −3.3 eV, which is sufficient for electron transfer to the PCBM is presented. A solar cell power conversion efficiency of 0.8% is reached for the composition P6: PCBM 1:4. From optical simulations were derived a maximum short circuit current density exceeding 16 mA · cm−2 at 500 nm thick films. Comparative measurements of the field effect hole mobility give an indication of two orders of magnitude lower charge carrier mobility of P6 in comparison to P3HT. The combined optical and electrical simulations of this system with a variation of the charge carrier mobilities support suspicion of a predominant limitation of the charge carrier mobility.

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Thiol‐Ene Radical Addition of L‐Cysteine Derivatives to Low Molecular Weight Polybutadiene
Authors: Lotti Luca , Coiai Serena , Ciardelli Francesco , Galimberti Maurizio , Passaglia Elisa
Published: August 2009

The functionalisation of a low molecular weight, liquid 1,2‐polybutadiene (PBL) was performed by the addition of either N‐acetyl‐L‐cysteine or its methyl ester through the thiol‐ene radical reaction. The functionalisation runs were carried out in 1,4‐dioxane solution and in the presence of a free radical initiator (2,2′‐azobisisobutyrronitrile, AIBN). The initial feed ratio polymer/cysteine derivative/initiator was varied, in order to highlight the occurrence of side reactions and to understand their possible influence on the process. The 1H NMR determination of the functionalisation degree brought out high addition degrees of thiols, regardless of the initial thiol/double bonds ratio. This caused a drastic change in the macroscopic properties of the PBL with improved solubility in hydrophilic solvents (for instance in alkaline aqueous solutions) and impressive increase of the glass transition temperature. The propagation of chiral properties from the functionalising agents to the modified polymers was evaluated by polarimetry and circular dichroism in solution.

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Phenylenevinylene Block Copolymers via Ring‐Opening Metathesis Polymerization
Authors: Yu Chin‐Yang , Kingsley James W. , Lidzey David G. , Turner Michael L.
Published: August 2009

Fully conjugated block copolymers containing 1,4‐ and 1,3‐phenylenevinylene repeating units can be prepared by the sequential ring opening metathesis polymerization of strained cyclophanedienes, initiated by ruthenium carbene complexes (Grubbs metathesis catalysts). The molecular weight of the constituent blocks can be tightly controlled by changing the catalyst to monomer ratio and the volume fraction of the block copolymers independently tailored by the ratio of the monomers employed. Extensive phase separation between the constituent blocks is observed in thin films of these polymers by atomic force microscopy and efficient energy transfer between blocks containing 1,4‐ and 1,3‐phenylenevinylene units can be seen in the photoluminescence of these materials.

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Electrically conductive carbon nanofiber/polyethylene composite: effect of melt mixing conditions
Authors: Al‐Saleh Mohammed H. , Sundararaj Uttandaraman
Published: August 2009

The effect of melt mixing conditions on the morphological, rheological, electrical, electromagnetic interference (EMI) shielding effectiveness (SE), and tensile properties of 7.5 vol% vapor grown carbon nanofiber (VGCNF)/polyethylene composites were investigated. 7.5 vol% VGCNF was used because such loading is required to obtain a composite with satisfactory EMI SE. The composites were compounded by melt mixing and the parts were prepared by hot‐compression molding. The dispersion and distribution of nanofibers were enhanced by increasing the mixing energy, i.e. mixing time and/or rotation speed. The influence of mixing energy on the electrical and EMI SE properties was found to be a function of rotation speed, i.e. shear stress. For composites compounded at 20 rpm, increasing the mixing energy from 70 to 2300 J/ml decreased the EMI SE from 29.5 to 23.9 dB. However, for composites prepared at 100 rpm, increasing the mixing energy from 600 to 1700 J/ml decreased the EMI SE from 25.4 to 18.6 dB. No considerable influence on the yield stress, Young's modulus, and strain at break were found for different processing conditions. Copyright © 2009 John Wiley & Sons, Ltd.
Out‐of‐hospital medication errors: a 6‐year analysis of the national poison data system
Authors: Shah Kanan , Barker Kimberly A.
Published: August 2009

Purpose

Previous research and reporting has focused on the incidence and prevention of medication errors in the hospital setting; however, no previous study has reported the frequencies, characteristics and outcomes of out‐of‐hospital medication (OHME) errors.

Method

Data from the National Poison Data System (NPDS) was collected for 2000–2005 and information regarding out‐of‐hospital medication errors reported to Poison Control Centers (PCC) was collected by a trained investigator.

Results

From 2000–2005 there were 1,166,116 OHME reported to PCC. Of these patients, 88,451 (7.5%) received medical evaluation by a healthcare provided and 229 (0.01%) deaths reported. The most common drug classes involved included cough/cold medications, analgesics, cardiovascular agents, antihistamines, antidepressants and antimicrobial agents. The most common error reported in both children and adults was taking or giving medication twice.

Conclusions

OHME occur frequently and the NPDS may be a useful resource for data collection and evaluation in this previously overlooked population. The majority of OHME reported did not result in any significant morbidity or mortality and were managed at home without need for healthcare referrral. Further study of OHME is needed, and in particular whether healthcare professionals can target educational instruction to patients so as to effectively reduce the frequency of the most common or injurious errors. Copyright © 2009 John Wiley & Sons, Ltd.
U.S. physician knowledge of the FDA‐approved indications and evidence base for commonly prescribed drugs: results of a national survey
Authors: Chen Donna T. , Wynia Matthew K. , Moloney Rachael M. , Alexander G. Caleb
Published: August 2009

Purpose

The Food and Drug Administration (FDA) regulates prescription drug marketing, not prescribing. However, off‐label use is common, often lacks supporting evidence, and may expose patients to unwarranted risk. We sought to determine physicians' knowledge of the FDA‐approved indications of commonly prescribed drugs, and to assess whether physicians' belief that an indication is FDA‐approved increases with level of evidence supporting such use.

Methods

We conducted a national random sample mail survey of 599 primary care physicians and 600 psychiatrists from November 2007 to August 2008. Physicians were presented with 14 drug‐indication pairs (e.g., gabapentin [Neurontin®] for diabetic neuropathy) that varied in their FDA‐approval status and levels of supporting evidence.

Results

The adjusted response rate was 47%, respondents were similar to non‐respondents, and physicians commonly prescribed the drugs examined. The average respondent accurately identified the FDA‐approval status of just over half of the drug‐indication pairs queried (mean 55%; median 57%). Accuracy increased modestly (mean 60%, median 63%) when limited to drugs the respondent reported having prescribed during the previous 12 months. There was a strong association between physicians' belief that an indication was FDA‐approved and greater evidence supporting efficacy for that use (Spearman's ρ 0.74, p < 0.001). However, 41% of physicians believed at least one drug‐indication pair with uncertain or no supporting evidence (e.g., quetiapine [Seroquel®] for dementia with agitation) was FDA approved.

Conclusions

These findings highlight a pressing need for more effective methods to inform physicians about the evidence base, or lack thereof, for drugs they prescribe off label. Copyright © 2009 John Wiley & Sons, Ltd.
Inhibitory effect of bionic fungicide 2‐allylphenol on Botrytis cinerea (Pers. ex Fr.) in vitro
Authors: Gong Shuangjun , Hao Jianjun , Xia Yuanyuan , Liu Xili , Li Jianqiang
Published: August 2009

BACKGROUND: 2‐Allylphenol is a registered fungicide in China to control fungal diseases on tomato, strawberry and apple. It is synthetic and structurally resembles the active ingredient ginkgol isolated from Ginkgo biloba L. bark. 2‐Allylphenol has been used in China for 10 years. However, its biochemical mode of action remains unclear. An in vitro study was conducted on the biochemical mechanism of 2‐allyphenol inhibiting Botrytis cinerea (Pers. ex Fr.).

RESULTS: The inhibition was approximately 3 times stronger when the fungus was grown on non‐fermentable source, glycerol, than that on a fermentable carbon source, glucose. Inhibition of B. cinerea and Magnaporthe oryzae (Hebert) Barr mycelial growth was markedly potentiated in the presence of salicylhydroxamic acid (SHAM), an inhibitor of mitochondrial alternative oxidase. Furthermore, at 3 h after treatment with 2‐allylphenol, oxygen consumption had recovered, but respiration was resistant to potassium cyanide and sensitive to SHAM, indicating that 2‐allylphenol had the ability to induce cyanide‐resistant respiration. The mycelium inhibited in the presence of 2‐allylphenol grew vigorously after being transferred to a fungicide‐free medium, indicating that 2‐allylphenol is a fungistatic compound. Adenine nucleotide assay showed that 2‐allylphenol depleted ATP content and decreased the energy charge values, which confirmed that 2‐allylphenol is involved in the impairment of the ATP energy generation system.

CONCLUSION: These results suggested that 2‐allylphenol induces cyanide‐resistant respiration and causes ATP decrease, and inhibits respiration by an unidentified mechanism. Copyright © 2009 Society of Chemical Industry
The effect of thermal treatment conditions employed in sol–gel method on the structure of ZnO thin films
Authors: Ehara Takashi , Otsuki Takafumi , Abe Junya , Ueno Takaaki , Ito Masahiro , Hirayama Takafumi
Published: August 2009

We have prepared ZnO thin films by the sol–gel method from a 2‐methoxyethanol solution of zinc acetate dihydrate stabilized by 2‐aminoethanol on SiO2 substrates. The structure of the films showed a significant dependency on thermal treatment temperature, not only in the final thermal‐annealing process at several hundreds of degrees, but also in the heat‐treatment after spin coating at lower temperature, which is performed to evaporate the organic solvent in the films. The intensity of the (0002) peak in X‐ray diffraction showed significant dependence on the heat treatment conditions after spin coating, which ranged from 100 to 300 °C. The temperature employed in the initial 10 min of the heat treatment was found to be important in determining the structure of the film. The results indicate that the elimination condition of the organic components is important for achieving high crystallinity
Mass spectral studies towards more reliable measurement of perfluorooctanesulfonic acid and other perfluorinated chemicals (PFCs) in food matrices using liquid chromatography/tandem mass spectrometry
Authors: Lloyd Antony S. , Bailey Victoria A. , Hird Simon J. , Routledge Anne , Clarke Don B.
Published: August 2009

Liquid chromatography/mass spectrometry (LC/MS) experiments are described, leading to a reliable method for the measurement of perfluorooctanesulfonic acid (PFOS) and other perfluorinated chemicals (PFCs) in foods. Separations were performed on new fluorinated stationary phases, RP Octyl (‐C8F17) or propyl‐perfluorobenzene (‐C3H6‐C6F5), to ensure resolution of PFOS and interfering taurohydroxycholate isomers. Aqueous ammonium formate (5 mM) and methanol were used as the mobile phases. The mass spectrometer was operated in negative electrospray ionisation mode, recording two transitions for each analyte and one for each internal standard. The purities of the analytical standards for the eleven target perfluoro analytes (C7 to C12 carboxylic acids, C4, C6 and C8 sulfonic acids, and octanesulfonamide (PFOSA)) were found to be in close agreement with the supplied values; the lowest purity was 91%. Five candidate internal standards were investigated, 13C4‐PFOS, 13C4‐perfluorooctanoic acid, 13C2‐perfluorodecanoic acid, D9‐n‐ethylperfluorooctanesulfonamidoethanol (D9‐n‐Et‐FOSE) and D3‐n‐methylperfluorooctanesulfonamide (D3‐n‐Me‐FOSA); the purities were all >98%. The use of tetrahydro‐PFOS generated backgrounds (>1 µg/kg) for perfluoroheptanoic acid and perfluorobutanesulfonic acid. Similarly D9‐n‐Et‐FOSE was unacceptable and D3‐n‐Me‐FOSA was volatile, leaving no clear candidate for normalisation of the measurement of PFOSA. Severe matrix‐induced suppression and enhancement effects influenced ionisation, making external calibration and quantification problematic. This was addressed by a parallel standard addition and matrix‐matching approach, comparing ionisation in methanol, in procedural blanks and in food‐based extracts. The limits of detection (LODs) of 0.001–0.01 µg/kg in solvent and 0.01–1 µg/kg in foods demonstrate that this method is suitable for the determination of PFCs in all food to the required 1 µg/kg reporting level. © Crown copyright 2009. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.
An optimum design of deep‐space downlinks affected by tropospheric attenuation
Authors: Matricciani Emilio
Published: August 2009

In the paper, we propose an optimum design of deep‐space downlinks made with 2 hops, at Ka band and above, in which each hop should be designed for providing half of the total noise‐to‐signal power ratio. We have derived this result from maximizing the ratio between the tropospheric attenuation in the 2‐hop downlink and that in the 1‐hop downlink. The design of the 1st hop (free‐space) of the 2‐hop downlink can reduce the spacecraft power, for the same antennas physical size, by increasing the carrier frequency from Ka band (32 GHz) to W band (80 GHz). This choice is not available in 1‐hop downlink design because of the huge Earth tropospheric attenuation expected in the W frequency band. To show a practical design, we have applied the theory to compare 1‐hop downlink design at 32 GHz to 2‐hop downlink design that adopts 32 or 80 GHz in the 1st hop. The calculations refer to spacecrafts located at two astronomical units (300×106 km, about planet Mars) and to NASA and ESA receiving stations located in Goldstone (California), Cebreros (Madrid, Spain), Canberra and New Norcia (Australia). At 0.1% outage probability, in an average year or in the worst month, 1‐hop downlinks show performance critical or close to fail, because of the large tropospheric attenuation (except at Goldstone), while 2‐hop downlinks always work. Copyright © 2009 John Wiley & Sons, Ltd.
Flexible High‐Conductivity Carbon‐Nanotube Interconnects Made by Rolling and Printing
Authors: Tawfick S. , O'Brien K. , Hart A. J.
Published: August 2009

Applications of carbon nanotubes (CNTs) in flexible and complementary metal‐oxide‐semiconductor (CMOS)‐based electronic and energy devices are impeded due to typically low CNT areal densities, growth temperatures that are incompatible with device substrates, and challenges in large‐area alignment and interconnection. A scalable method for continuous fabrication and transfer printing of dense horizontally aligned CNT (HA‐CNT) ribbon interconnects is presented. The process combines vertically aligned CNT (VA‐CNT) growth by thermal chemical vapor deposition, a novel mechanical rolling process to transform the VA‐CNTs to HA‐CNTs, and adhesion‐controlled transfer printing without needing a carrier film. The rolling force determines the HA‐CNT packing fraction and the HA‐CNTs are processed by conventional lithography. An electrical resistivity of 2 mΩ · cm is measured for ribbons having 800‐nm thickness, while the resistivity of copper is 100 times lower, a value that exceeds most CNT assemblies made to date, and significant improvements can be made in CNT structural quality. This rolling and printing process could be scaled to full wafer areas and more complex architectures such as continuous CNT sheets and multidirectional patterns could be achieved by straightforward design of the CNT growth process and/or multiple rolling and printing sequences.
Probing Cell‐Type‐Specific Intracellular Nanoscale Barriers Using Size‐Tuned Quantum Dots
Authors: Williams Yvonne , Sukhanova Alyona , Nowostawska Małgorzata , Davies Anthony M. , Mitchell Siobhan , Oleinikov Vladimir , Gun'ko Yurii , Nabiev Igor , Kelleher Dermot , Volkov Yuri
Published: August 2009

The compartmentalization of size‐tuned luminescent semiconductor nanocrystal quantum dots (QDs) in four distinctive cell lines, which would be representative of the most likely environmental exposure routes to nanoparticles in humans, is studied. The cells are fixed and permeabilized prior to the addition of the QDs, thus eliminating any cell‐membrane‐associated effects due to active QD uptake mechanisms or to specificity of signaling routes in different cell types, but leaving intact the putative physical subcellular barriers. All quantitative assays are performed using a high content analysis (HCA) platform, thereby obtaining robust data on large cell populations. While smaller QDs 2.1 nm in diameter enter the nuclei and localize to the nucleoli in all cell types, the rate and dynamics of their passage vary depending on the cell origin. As the QD size is increased to 4.4 nm, penetration into the cell is reduced but each cell line displays its own cutoff size thresholds reflecting cell‐type‐determined cytoplasmic and nuclear pore penetration specificity. These results give rise to important considerations regarding the differential compartmentalization and susceptibility of organs, tissues, and cells to nanoparticles, and may be of prime importance for biomedical imaging and drug‐delivery research employing nanoparticle‐based probes and systems.
Single‐needle laser treatment with drainage of hydrothorax in fetal bronchopulmonary sequestration with hydrops
Authors: Witlox R. S. G. M. , Lopriore E. , Walther F. J. , Rikkers‐Mutsaerts E. R. V. M. , Klumper F. J. C. M. , Oepkes D.
Published: August 2009

Bronchopulmonary sequestration (BPS) is sometimes associated with hydrothorax and hydrops in utero. In the absence of fetal hydrops, perinatal outcome is favorable and justifies expectant management. In the presence of fetal hydrops, perinatal outcome is reported to be extremely poor and intervention should be considered. Therapeutic options include open fetal surgery, minimally invasive coagulation of the blood supply and thoracoamniotic shunting. We present the first case of fetal hydrops and a large hydrothorax due to BPS treated successfully with one ultrasound‐guided thin needle insertion, through which both laser coagulation of the feeding artery and drainage of the hydrothorax were performed. Following the procedure the hydrothorax and hydrops gradually disappeared and the BPS diminished in size. A healthy neonate was delivered uneventfully at term. We describe the case and discuss the different therapeutic options. Copyright © 2009 ISUOG. Published by John Wiley & Sons, Ltd.
Computational modeling of mammalian signaling networks
Authors: Hughey Jacob J. , Lee Timothy K. , Covert Markus W.
Published: August 2009

One of the most exciting developments in signal transduction research has been the proliferation of studies in which a biological discovery was initiated by computational modeling. In this study, we review the major efforts that enable such studies. First, we describe the experimental technologies that are generally used to identify the molecular components and interactions in, and dynamic behavior exhibited by, a network of interest. Next, we review the mathematical approaches that are used to model signaling network behavior. Finally, we focus on three specific instances of ‘model‐driven discovery’: cases in which computational modeling of a signaling network has led to new insights that have been verified experimentally. Copyright © 2009 John Wiley & Sons, Inc.

This article is categorized under:

Models of Systems Properties and Processes > Cellular Models
MicroRNA targeting in mammalian genomes: genes and mechanisms
Authors: Muljo S. A. , Kanellopoulou C. , Aravind L.
Published: August 2009

We briefly review the history of microRNA (miRNA) research and some of the lessons learnt. To provide some insights as to how and why miRNAs came into existence, we consider the evolution of the RNA interference machinery, miRNA genes, and their targets. We highlight the importance of systems biology approaches to integrate miRNAs as an essential subnetwork for modulating gene expression programs. Building accurate computational models that can simulate highly complex cell‐specific gene expression patterns in mammals will lead to a better understanding of miRNAs and their targets in physiological and pathological situations. The impact of miRNAs on medicine, either as potential disease predisposing factors, biomarkers, or therapeutics, is highly anticipated and has started to reveal itself. Copyright © 2010 John Wiley & Sons, Inc.

This article is categorized under:

Biological Mechanisms > Regulatory Biology
The Provision of Surgical Care by International Organizations in Developing Countries: A Preliminary Report
Authors: McQueen K. A. Kelly , Hyder Joseph A. , Taira Breena R. , Semer Nadine , Burkle Frederick M. , Casey Kathleen M.
Published: August 2009

Objective

Emerging data demonstrate that a large fraction of the global burden of disease is amenable to surgical intervention. There is a paucity of data related to delivery of surgical care in low‐ and middle‐income countries, and no aggregate data describe the efforts of international organizations to provide surgical care in these settings. This study was designed to describe the roles and practices of international organizations delivering surgical care in developing nations with regard to surgical types and volume, outcomes tracking, and degree of integration with local health systems.

Methods

Between October 2008 and December 2008, an Internet‐based confidential questionnaire was distributed to 99 international organizations providing humanitarian surgical care to determine their size, scope, involvement in surgical data collection, and integration into local systems.

Results

Forty‐six international organizations responded (response rate 46%). Findings reveal that a majority of organizations that provide surgery track numbers of cases performed and immediate outcomes, such as mortality. In general, these groups have mechanisms in place to track volume and outcomes, provide for postintervention follow‐up, are committed to providing education, and work in conjunction with local health organizations and providers. Whereas most organizations surveyed provided fewer than 500 surgical procedures annually, more than half had the capacity to provide emergency services. In addition, a great diversity of specialized surgical care was provided, including obstetrics, orthopedic, plastic, and ophthalmologic surgery.

Conclusions

International organizations providing surgical services are diverse in size and breadth of surgical services provided yet, with consistency, provide rudimentary analysis, postoperative follow‐up care, and both education and integration of health services at the local level. The role of international organizations in the delivery of surgery is an important index, worthy of further evaluation.
Glyceryl triacetate for Canavan disease: A low‐dose trial in infants and evaluation of a higher dose for toxicity in the tremor rat model
Authors: Madhavarao C. N. , Arun P. , Anikster Y. , Mog S. R. , Staretz‐Chacham O. , Moffett J. R. , Grunberg N. E. , Gahl W. A. , Namboodiri A. M. A.
Published: August 2009

Canavan disease (CD) is a fatal dysmyelinating genetic disorder associated with aspartoacylase deficiency, resulting in decreased brain acetate levels and reduced myelin lipid synthesis in the developing brain. Here we tested tolerability of a potent acetate precursor, glyceryl triacetate (GTA), at low doses in two infants diagnosed with CD, aged 8 and 13 months. Much higher doses of GTA were evaluated for toxicity in the tremor rat model of CD. GTA was given orally to the infants for up to 4.5 and 6 months, starting at 25 mg/kg twice daily, doubling the dose weekly until a maximum of 250 mg/kg reached. Wild‐type and tremor rat pups were given GTA orally twice daily, initially at a dose of 4.2 g/kg from postnatal days 7 through 14, and at 5.8 g/kg from day 15 through 23, and thereafter in food (7.5%) and water (5%). At the end of the trial (~90 to 120 days) sera and tissues from rats were analysed for changes in blood chemistry and histopathology. GTA treatment caused no detectable toxicity and the patients showed no deterioration in clinical status. In the high‐dose animal studies, no significant differences in the mean blood chemistry values occurred between treated and untreated groups, and no lesions indicating toxicity were detectable in any of the tissues examined. Lack of GTA toxicity in two CD patients in low‐dose trials, as well as in high‐dose animal studies, suggests that higher, effective dose studies in human CD patients are warranted.
Operative versus non-operative management of pediatric medial epicondyle fractures: A systematic review
Authors: Kamath Atul F. , Baldwin Keith , Horneff John , Hosalkar Harish S.
Published: August 2009

Purpose

There is ongoing debate about the management of medial epicondyle fractures in the pediatric population. This systematic review evaluated non-operative versus operative treatment of medial epicondyle fractures in pediatric and adolescent patients over the last six decades.

Methods

A systematic review of the available literature was performed. Frequency-weighted mean union times were used to compare union rates for closed versus open treatments. Moreover, functional outcomes and range-of-motion variables were correlated with varying treatment modalities. Any complications, including ulnar nerve symptoms, pain, instability, infection, and residual deformity, were cataloged.

Results

Fourteen studies, encompassing 498 patients, met the inclusion/exclusion criteria. There were 261 males and 132 female patients; the frequency-weighted average age was 11.93 years. The follow-up range was 6–216 months. Under the cumulative random effects model, the odds of union with operative fixation was 9.33 times the odds of union with non-operative treatment ( P < 0.0001). There was no significant difference between operative and non-operative treatments in terms of pain at final follow-up ( P = 0.73) or ulnar nerve symptoms ( P = 0.412).

Conclusions

Operative treatment affords a significantly higher union rate over the non-operative management of medial epicondyle fractures. There was no difference in pain at final follow-up between operative and non-operative treatments. As surgical indications evolve, and the functional demands of pediatric patients increase, surgical fixation should be strongly considered to achieve stable fixation and bony union.
Molecular Markers for Sweet Sorghum Based on Microarray Expression Data
Authors: Calviño Martín , Miclaus Mihai , Bruggmann Rémy , Messing Joachim
Published: August 2009

Using an Affymetrix sugarcane genechip, we previously identified 154 genes differentially expressed between grain and sweet sorghum. Although many of these genes have functions related to sugar and cell wall metabolism, dissection of the trait requires genetic analysis. Therefore, it would be advantageous to use microarray data for generation of genetic markers, shown in other species as single-feature polymorphisms (SFPs). As a test case, we used the GeSNP software to screen for SFPs between grain and sweet sorghum. Based on this screen, out of 58 candidate genes, 30 had single-nucleotide polymorphisms (SNPs) from which 19 had validated SFPs. The degree of nucleotide polymorphism found between grain and sweet sorghum was in the order of one SNP per 248 base pairs, with chromosome 8 being highly polymorphic. Indeed, molecular markers could be developed for a third of the candidate genes, giving us a high rate of return by this method.
Evidence that the major metabolites accumulating in hyperornithinemia–hyperammonemia–homocitrullinuria syndrome induce oxidative stress in brain of young rats
Authors: Amaral Alexandre Umpierrez , Leipnitz Guilhian , Fernandes Carolina Gonçalves , Seminotti Bianca , Zanatta Ângela , Viegas Carolina Maso , Dutra‐Filho Carlos Severo , Wajner Moacir
Published: August 2009

Ornithine and homocitrulline are the major metabolites accumulating in hyperornithinemia–hyperammonemia–homocitrullinuria syndrome, a genetic disorder characterized by neurological regression whose pathogenesis is still not understood. The present work investigated the in vitro effects of ornithine and homocitrulline on important parameters of oxidative stress in cerebral cortex from young rats. Ornithine significantly increased chemiluminescence and thiobarbituric acid‐reactive substances levels, indicators of lipid peroxidation, while homocitrulline only augmented chemiluminescence values. Furthermore, ornithine‐induced increase of thiobarbituric acid‐reactive substances levels was attenuated (melatonin and reduced glutathione) or totally prevented (α‐tocopherol) by free radical scavengers, suggesting that reactive species were involved in the lipid oxidative damage. We also observed that ornithine and homocitrulline significantly decreased the tissue antioxidant defenses, determined by reduced glutathione concentrations, the major non‐enzymatic antioxidant defense found in the brain. Homocitrulline reduction of glutathione levels was completely prevented by melatonin and α‐tocopherol, whereas ornithine‐induced decrease of glutathione levels was only attenuated by these free radical scavengers. Ornithine and homocitrulline also induced protein oxidative damage, increasing carbonyl formation and sulfhydryl oxidation. In contrast, these amino acids did not affect nitric oxide production, indicating that nitrogen reactive species were not implicated in the lipid and oxidative damage provoked by ornithine and homocitrulline. Therefore, it is presumed that the major metabolites accumulating in hyperornithinemia–hyperammonemia–homocitrullinuria syndrome elicit oxidative stress and that this pathomechanism may possibly be involved in the brain damage found in patients affected by this disorder.
A two-thirds of success. Poland’s post-communist transformation 1989–2009
Authors: Kolodko Grzegorz W.
Published: August 2009

The progress toward institutional changes should be evaluated through the prism of their influence on a country’s development abilities. In Poland, during the twenty years of comprehensive systemic shift, gross domestic product (GDP) has increased more than in any other post-communist country. While judging the transformation progress, not only the improvement of competitiveness and growth in terms of quantity must be taken into account, but also social and cultural aspects. There have been five distinct periods in Poland, from the viewpoint of economic growth. Had there been a better policy coordination of systemic change and socio-economic development, GDP over the periods considered could have increased by a half more. This opportunity has been missed due to the intermittent implementation of wrong economic policies based on wrong economic theories. Poland’s transformation can be seen as a success, but only to the extent of two-thirds of its potential.
The Language of Liberty and Law: James Wilson on America's Written Constitution
Authors: ZINK JAMES R.
Published: August 2009

Although contemporary Americans take it for granted that a “constitution” is a written document, written constitutions were almost unprecedented at America's founding. James Wilson, one of the most significant yet overlooked of America's founders, offers a comprehensive theory of America's written constitution. Wilson argues that the written-ness of the U.S. Constitution serves two essential functions. As an initial matter, it memorializes the primacy of liberty by announcing that the authority of government derives only from a free people. Perhaps more importantly, however, the written constitution uplifts and refines the character of its citizens, and thus helps to constitute a people. A review of Wilson's writings and speeches reveals how, even in a rights-centric political order, the written constitution helps to cultivate moderate and civic-minded citizens without diminishing the fundamental importance of individual rights.
‘I was never more in love with an olde howse nor never newe worke coulde be better bestowed’: The Earl of Leicester’s remodelling of Kenilworth Castle for Queen Elizabeth I
Authors: Morris Richard K
Published: August 2009

Kenilworth, though a castle in name, was converted by Robert Dudley, earl of Leicester, into the first great Elizabethan progress house. This article aims to provide the first thorough account and assessment of his architectural works at Kenilworth. It is based primarily on the author’s long acquaintance with the castle’s building fabric, supplemented by the opportunities afforded by the recent programme of works undertaken by English Heritage and by new documentary information. Among the discoveries are several works (previously attributed to Leicester) which can be assigned to his father, the duke of Northumberland (c 1553) and also evidence for an early phase of work for Leicester himself (c 1568–9).

His most important architectural achievement, Leicester’s Building, is shown to have been built specifically to accommodate Queen Elizabeth, and the functions of its rooms are reconstructed. Evidence is assembled to show that Leicester’s Building was erected between 1570 and 1572, in anticipation of her 1572 visit. Archaeological analysis of its standing fabric shows that it underwent considerable modification subsequently, presumably in readiness for the 1575 progress. The physical evidence for Leicester’s other architectural works at the castle is assessed, including the remodelling of the great tower and the south and east ranges of the inner court.

The reasons for Leicester’s grand scheme are considered, as well as the importance of his architecture in the period and the roles of his architects and craftsmen, particularly William Spicer. It is argued that Leicester’s Building was the prototype for the midlands ‘high house’ (of which Hardwick New Hall is the best-known exemplar) and was probably the most significant model for the eclectic, linear style which came to dominate great houses in the second half of Elizabeth’s reign.