bluuebunny/crossref_metadata_2025 huggingface dataset:
Heart-Kidney Interaction: Epidemiology of Cardiorenal Syndromes
Authors: Cruz Dinna N. , Bagshaw Sean M.
Published: December 2010

Cardiac and kidney diseases are common, increasingly encountered, and often coexist. Recently, the Acute Dialysis Quality Initiative (ADQI) Working Group convened a consensus conference to develop a classification scheme for the CRS and for five discrete subtypes. These CRS subtypes likely share pathophysiologic mechanisms, however, also have distinguishing clinical features, in terms of precipitating events, risk identification, natural history, and outcomes. Knowledge of the epidemiology of heart-kidney interaction stratified by the proposed CRS subtypes is increasingly important for understanding the overall burden of disease for each CRS subtype, along with associated morbidity, mortality, and health resource utilization. Likewise, an understanding of the epidemiology of CRS is necessary for characterizing whether there exists important knowledge gaps and to aid in the design of clinical studies. This paper will provide a summary of the epidemiology of the cardiorenal syndrome and its subtypes.
Effects of IFN-B on TRAIL and Decoy Receptor Expression in Different Immune Cell Populations from MS Patients with Distinct Disease Subtypes
Authors: Hebb Andrea L. O. , Moore Craig S. , Bhan Virender , Robertson George S.
Published: December 2010

Using quantitative RT-PCR, we compared mRNA levels for TRAIL [tumor necrosis factor (TNF)–related apoptosis-inducing ligand] and its receptors in various immune cell subsets derived from the peripheral blood of untreated normal subjects (NS) and patients with distinct subtypes of multiple sclerosis (MS): active relapsing-remitting MS (RRA), quiescent relapsing-remitting MS (RRQ), secondary-progressive MS (SPMS) or primary-progressive MS (PPMS). Consistent with a role for TRAIL in the mechanism of action of interferon-β (IFN-β), TRAIL mRNA levels were increased in monocytes from patients clinically responsive to IFN-β (RRQ) but not those unresponsive to this therapeutic (RRA). TRAIL-R3 (decoy receptor) expression was elevated in T cells from untreated RRMS patients while IFN-β therapy reversed this increase suggesting that IFN-β may promote the apoptotic elimination of autoreactive T cells by increasing the amount of TRAIL available to activate TRAIL death receptors. Serum concentrations of soluble TRAIL were increased to a similar extent by IFN-β therapy in RRQ, RRA and SPMS patients that had not generated neutralizing antibodies against this cytokine. Although our findings suggest altered TRAIL signaling may play a role in MS pathogenesis and IFN-β therapy, they do not support use of TRAIL as a surrogate marker for clinical responsiveness to this therapeutic.
Lipid Rafts: Linking Alzheimer′s Amyloid‐βProduction, Aggregation, and Toxicity at Neuronal Membranes
Authors: Rushworth Jo V. , Hooper Nigel M.
Published: December 2010

Lipid rafts are membrane microdomains, enriched in cholesterol and sphingolipids, into which specific subsets of proteins and lipids partition, creating cell‐signalling platforms that are vital for neuronal functions. Lipid rafts play at least three crucial roles in Alzheimer′s Disease (AD), namely, in promoting the generation of the amyloid‐β(Aβ) peptide, facilitating its aggregation upon neuronal membranes to form toxic oligomers and hosting specific neuronal receptors through which the AD‐related neurotoxicity and memory impairments of the Aβoligomers are transduced. Recent evidence suggests that Aβoligomers may exert their deleterious effects through binding to, and causing the aberrant clustering of, lipid raft proteins including the cellular prion protein and glutamate receptors. The formation of these pathogenic lipid raft‐based platforms may be critical for the toxic signalling mechanisms that underlie synaptic dysfunction and neuropathology in AD.
Lead, Manganese, and Methylmercury as Risk Factors for Neurobehavioral Impairment in Advanced Age
Authors: Weiss Bernard
Published: December 2010

Contamination of the environment by metals is recognized as a threat to health. One of their targets is the brain, and the adverse functional effects they induce are reflected by neurobehavioral assessments. Lead, manganese, and methylmercury are the metal contaminants linked most comprehensively to such disorders. Because many of these adverse effects can appear later in life, clues to the role of metals as risk factors for neurodegenerative disorders should be sought in the exposure histories of aging populations. A review of the available literature offers evidence that all three metals can produce, in advanced age, manifestations of neurobehavioral dysfunction associated with neurodegenerative disease. Among the critical unresolved questions is timing; that is, during which periods of the lifespan, including early development, do environmental exposures lay the foundations for their ultimate effects?
Iron and Mechanisms of Neurotoxicity
Authors: Salvador Gabriela A. , Uranga Romina M. , Giusto Norma M.
Published: December 2010

The accumulation of transition metals (e.g., copper, zinc, and iron) and the dysregulation of their metabolism are a hallmark in the pathogenesis of several neurodegenerative diseases. This paper will be focused on the mechanism of neurotoxicity mediated by iron. This metal progressively accumulates in the brain both during normal aging and neurodegenerative processes. High iron concentrations in the brain have been consistently observed in Alzheimer′s (AD) and Parkinson′s (PD) diseases. In this connection, metalloneurobiology has become extremely important in establishing the role of iron in the onset and progression of neurodegenerative diseases. Neurons have developed several protective mechanisms against oxidative stress, among them, the activation of cellular signaling pathways. The final response will depend on the identity, intensity, and persistence of the oxidative insult. The characterization of the mechanisms mediating the effects of iron‐induced increase in neuronal dysfunction and death is central to understanding the pathology of a number of neurodegenerative disorders.
Metabolic Syndrome and Outcomes after Renal Intervention
Authors: Vykoukal Daynene , Davies Mark G.
Published: December 2010

Metabolic syndrome significantly increases the risk for cardiovascular disease and chronic kidney disease. The increased risk for cardiovascular diseases can partly be caused by a prothrombotic state that exists because of abdominal obesity. Multiple observational studies have consistently shown that increased body mass index as well as insulin resistance and increased fasting insulin levels is associated with chronic kidney disease, even after adjustment for related disorders. Metabolic syndrome appears to be a risk factor for chronic kidney disease, likely due to the combination of dysglycemia and high blood pressure. Metabolic syndrome is associated with markedly reduced renal clinical benefit and increased progression to hemodialysis following endovascular intervention for atherosclerotic renal artery stenosis. Metabolic syndrome is associated with inferior early outcomes for dialysis access procedures.
Development of Bioartificial Myocardium Using Stem Cells and Nanobiotechnology Templates
Authors: Chachques Juan Carlos
Published: December 2010

Cell-based regenerative therapy is undergoing experimental and clinical trials in cardiology, in order to limit the consequences of decreased contractile function and compliance of damaged ventricles following myocardial infarction. Over 1000 patients have been treated worldwide with cell-based procedures for myocardial regeneration. Cellular cardiomyoplasty seems to reduce the size and fibrosis of infarct scars, limit adverse postischemic remodelling, and improve diastolic function. The development of a bioartificial myocardium is a new challenge; in this approach, tissue-engineered procedures are associated with cell therapy. Organ decellularization for bioscaffolds fabrication is a new investigated concept. Nanomaterials are emerging as the main candidates to ensure the achievement of a proper instructive cellular niche with good drug release/administration properties. Investigating the electrophysiological properties of bioartificial myocardium is the challenging objective of future research, associating a multielectrode network to provide electrical stimulation could improve the coupling of grafted cells and scaffolds with host cardiomyocytes. In summary, until now stem cell transplantation has not achieved clear hemodynamic benefits for myocardial diseases. Supported by relevant scientific background, the development of myocardial tissue engineering may constitute a new avenue and hope for the treatment of myocardial diseases.
Saddle Pulmonary Embolism in a Cancer Patient with Thrombocytopenia: A Treatment Dilemma
Authors: Zalpour Ali , Hanzelka Katy , Patlan John T. , Rozner Marc A. , Yusuf Syed Wamique
Published: December 2010

The association between cancer and venous thromboembolism (VTE) is well established. Saddle pulmonary embolism is not uncommon in hospitalized cancer patients and confers a higher mortality. We report a case of saddle pulmonary embolism in a cancer patient with thrombocytopenia, discuss the bleeding risks, complexity of managing such patients and review current guidelines.
Short-Term Prognostic Index for Breast Cancer: NPI or Lpi
Authors: Van Belle V. , Decock J. , Hendrickx W. , Brouckaert O. , Pintens S. , Moerman P. , Wildiers H. , Paridaens R. , Christiaens M. R. , Van Huffel S. , Neven P.
Published: December 2010

Axillary lymph node involvement is an important prognostic factor for breast cancer survival but is confounded by the number of nodes examined. We compare the performance of the log odds prognostic index (Lpi), using a ratio of the positive versus negative lymph nodes, with the Nottingham Prognostic Index (NPI) for short-term breast cancer specific disease free survival. A total of 1818 operable breast cancer patients treated in the University Hospital of Leuven between 2000 and 2005 were included. The performance of the NPI and Lpi were compared on two levels: calibration and discrimination. The latter was evaluated using the concordance index (cindex), the number of patients in the extreme groups, and difference in event rates between these. The NPI had a significant higher cindex, but a significant lower percentage of patients in the extreme risk groups. After updating both indices, no significant differences between NPI and Lpi were noted.
Ceramide and Related‐Sphingolipid Levels Are Not Altered in Disease‐Associated Brain Regions of APPSL and APPSL/PS1M146L Mouse Models of Alzheimer′s Disease: Relationship with the Lack of Neurodegeneration?
Authors: Barrier Laurence , Fauconneau Bernard , Noël Anastasia , Ingrand Sabrina
Published: December 2010

There is evidence linking sphingolipid abnormalities, APP processing, and neuronal death in Alzheimer′s disease (AD). We previously reported a strong elevation of ceramide levels in the brain of the APPSL/PS1Ki mouse model of AD, preceding the neuronal death. To extend these findings, we analyzed ceramide and related‐sphingolipid contents in brain from two other mouse models (i.e., APPSL and APPSL/PS1M146L) in which the time‐course of pathology is closer to that seen in most currently available models. Conversely to our previous work, ceramides did not accumulate in disease‐associated brain regions (cortex and hippocampus) from both models. However, the APPSL/PS1Ki model is unique for its drastic neuronal loss coinciding with strong accumulation of neurotoxic Aβ isoforms, not observed in other animal models of AD. Since there are neither neuronal loss nor toxic Aβ species accumulation in APPSL mice, we hypothesized that it might explain the lack of ceramide accumulation, at least in this model.
Neonatal Cyanosis: Diagnostic and Management Challenges
Authors: Izraelit A. , Ten V. , Krishnamurthy G. , Ratner V.
Published: December 2010

Neonatal central cyanosis is always a sign of serious pathological processes and may involve diverse organs and impose a significant diagnostic and therapeutic challenge. Here, we report an unusual presentation of Ebstein's anomaly, a rare congenital heart malformation, as the cause of central cyanosis in a one-week-old full-term infant. Initiation of PEG1 therapy in neonates with Ebstein's anomaly always needs a very careful consideration because of a high risk for the development of a “circular shunt” leading to severe deterioration of multiple organs perfusion.
Rapidly-Converging Series Representations of a Mutual-Information Integral
Authors: Torrieri Don , Valenti Matthew
Published: December 2010

This paper evaluates a mutual-information integral that appears in EXIT-chart analysis and the capacity equation for the binary-input AWGN channel. Rapidly-converging series representations are derived and shown to be computationally efficient. Over a wide range of channel signal-to-noise ratios, the series are more accurate than the Gauss-Hermite quadrature and comparable to Monte Carlo integration with a very large number of trials.
Digestive Malacoplakia in Children: Case Report
Authors: Bouguila J. , Brahim K. , Mokni M. , Skandrani K. , Harbi A. , Essoussi A. S. , Boughammoura L.
Published: December 2010

Malacoplakia is a form of chronic granulomatous inflammatory reaction that rarely affects the pediatric age group. The gastrointestinal system is the second most common site for the occurrence of malacoplakia. We report the case of a 9-year-old girl who was hospitalized for abdominal pain, chronic diarrhea, and rectal hemorrhage. The endoscopic examinations and histopathology confirmed the diagnosis of intestinal malacoplakia. We successfully treated her with oral levofloxacin. This disease does not have any specific clinical or biological signs, and the diagnosis is exclusively based on histology.
The viscosity of dimethyl silicone oil and the concentration of absorbed air
Authors: Fan Yurun , Wang Kun
Published: December 2010

We studied the viscosity behavior of 500 cSt dimethyl silicone oil with considerable concentration of absorbed air. For this purpose, a Couette rheometer with a transparent rotating outer cylinder and a fixed inner cylinder was established, in which the ambient pressure is controlled by a piston–cylinder apparatus. Careful torque calibration and equilibrium examination for the air–silicone–oil mixture were carried out. In the range of ambient pressure from 1 to 5 atm, corresponding to the air molar fraction from 11 to 35%, it was found that viscosity of the silicone oil decreases monotonically as the air concentration increases. The viscosity variation can be explained by the Eyring's model in which the free energy of activation is modified to account for the nonideality of the air–silicone–oil mixture. The excess free energy used to fit the viscosity variation is approximately equal to that used in the Krichevsky–Ilinskaya equation, which accounts for the nonideal solubility of the air–silicone–oil solution. The activation energy in the Arrhenius equation for viscosity–temperature relationship is identified as the activation enthalpy. © 2011 American Institute of Chemical Engineers AIChE J, 2011
Solution combustion synthesis of metal nanopowders: Copper and copper/nickel alloys
Authors: Kumar A. , Wolf E. E. , Mukasyan A. S.
Published: December 2010

Based on a general methodology for the preparation of metal–nanopowders by solution combustion synthesis (SCS), the reaction pathways for SCS of pure copper and copper–nickel alloy nanopowders are investigated. It is confirmed that the necessary condition for SCS of metals in a metal‐nitrate oxidizer–glycine system is the property of the oxidizer to decompose with formation of HNO3 species. In this case, for compositions with excess of glycine, a hydrogen reducing atmosphere develops in the reaction front, leading to the formation of reduced metals. The proposed reaction pathways are supported by X‐ray diffraction analysis of the quenched samples and DTA–TGA studies of the Cu(NO3)2·6H2O–glycine and Ni(NO3)2·6H2O/Cu(NO3)2·6H2O–glycine systems. The results show that the formation of Cu2O and CuO oxide phases takes place at early stages in the reaction front followed by their reduction to pure Cu phase in the postcombustion zones. However, in a Cu–Ni alloy, a fraction of intermetallic Cu–Ni phase appeared directly in the combustion front, whereas the rest of the oxygen‐free alloy formed through reduction of oxide phases. © 2011 American Institute of Chemical Engineers AIChE J, 2011
Transformation of hemipentahydrate to monohydrate of risedronate monosodium by seed crystallization in solution
Authors: Nguyen Thi Nhat Phuong , Kim Kwang‐Joo
Published: December 2010

The transformation from a hemipentahydrate to a monohydrate of risedronate monosodium was studied by seed crystallization in solution. By using the in‐line measurement based on ultrasonic measuring technique and the off‐line measurements such as optical microscopic and crystallography, transformation of hydrate forms and crystallization of monohydrate were observed. The effect of concentration of solution and solid fraction of suspension on the ultrasonic velocity was found. The hydrate composition, concentration of solution, and supersaturation during the transformation were estimated with elapsed time. The effect of monohydrate seed, agitation rate and temperature on the induction time, transformation, and crystallization was also investigated. Eventually, transformation from hemipentahydrates to monohydrates and crystallization of monohydrate were analyzed successfully from in‐line measuring technique. © 2011 American Institute of Chemical Engineers AIChE J, 2011
Brief communication: Developmental dysplasia of the hip in medieval London
Authors: Mitchell Piers D. , Redfern Rebecca C.
Published: December 2010

Developmental dysplasia of the hip (DDH) is a spectrum of disease starting in childhood and in many cases persisting into adulthood. The spectrum ranges from acetabular dysplasia, through hip subluxation to dislocation. The aim of this research was to determine the prevalence and pathoanatomy of acetabular dysplasia and subluxation in excavated human skeletal remains, to complement past research on dislocation in DDH. The material under study was the medieval cemetery of St. Mary Spital in London, in use from c.1100 to 1539 AD. A series of 572 adults with both hips preserved were analyzed. Acetabular dysplasia was indicated by a shallow acetabulum with upward sloping roof. Subluxation was suggested by degenerative change along the margin of the acetabulum suggestive of labral tears, and degenerative change in the outer part of the acetabular roof suggestive of osteoarthritis. The prevalence of DDH (acetabular dysplasia, subluxation, or dislocation) was 1.7%. Because this a congenital musculoskeletal disorder of relatively high frequency, with significant variation in prevalence between populations around the world, it is a topic that warrants targeted research from physical anthropologists studying past populations. Am J Phys Anthropol, 2011. © 2010 Wiley‐Liss, Inc.
Relationship between canine dimorphism and mandibular morphology in the hamadryas baboon and the Japanese monkey
Authors: Fukase Hitoshi
Published: December 2010

To examine morphological interrelationships between canine size and mandibular corpus shape, inter‐sex comparisons were made in the hamadryas baboon and the Japanese monkey, known to display extreme and moderate canine dimorphism, respectively. Results of adult comparisons showed that all mandibular dimensions were significantly larger in the males than in the females in both species. In the hamadryas baboon, the males also exhibited a higher ratio of anterior to posterior corpus height than the females. This sex difference in corpus shape was not significant in the Japanese monkey, indicating lack of involvement of canine dimorphism. Analysis of mandibular growth patterns in the hamadryas baboon demonstrated that significant sexual size difference did not occur before incisor eruption, and that the anteriorly high corpus of the adult male mandible was associated with a rapidly increasing symphyseal height after incisor eruption. It was also shown that the female canine started to erupt shortly after incisor eruption, while the forming male canine continued to stay near the mandibular base and developed further in size until eruption. The relative positions of the incisors keptshifting upwards even after eruption in the males, while they hardly changed in the females. It is therefore suggested that the prolonged development and size increase of the male canine is accompanied by further enlargement of the symphysis, resulting in the higher anterior corpus of the adult males compared to the adult females. The results thus indicate the importance of understanding the spatial relationships of the developing teeth in interpreting mandibular morphology. Am J Phys Anthropol, 2011. © 2010 Wiley‐Liss, Inc.
Influence of hydrophobic tail on the adsorption of isomeric alcohols at air/water interface
Authors: Le T. N. , Phan C. M. , Ang H. M.
Published: December 2010

This study investigated the influence of molecular structures of alcohols on adsorption behaviour. The adsorption isotherm of nonanols, octanols and hexanols at air–water interface was determined using the Wilhelmy plate method, in combination with an automatic dispenser. The experimental data were fitted with Frumkin–Langmuir isotherms by applying least‐squares techniques in Solver (MS Excel) to identify the adsorption parameters. These parameters can be used to quantify and compare the surface behaviours of all the investigated surfactants. It has been found that with the same concentration, the straight chain alcohols had stronger surface activity than the corresponding branched alcohols. The adsorption activity was also strongly related to the position of the hydroxyl group, with primary alcohols showing strongest adsorption. Overall, it was found that the surface activity decreased with increasing bulkiness of the alcohol structure. The results also highlighted the significance of low concentration data in determining the adsorption isotherm of alcohols. Copyright © 2010 Curtin University of Technology and John Wiley & Sons, Ltd.
Atomic absorption spectrometric determination of cadmium and lead in soil after total digestion
Authors: Naeem Kashif , Yawar Wasim , Akhter Perveen , Rehana Ishrat
Published: December 2010

To establish the baseline levels of cadmium (Cd) and lead (Pb) in Pakistani soil, samples were collected from various ecological areas of the country. A total digestion procedure using an acid mixture of HFHClO4 was investigated for heavy metal analysis of soil samples. Concentrations of these elements were measured using flame and graphite furnace atomic absorption spectrometry. Measured elemental contents of Cd and Pb varied from 0.41–1.18 and 22.47–95.75 µg/g with geometric mean 0.73 and 47.99 and geometric standard deviation concentrations of 1.36 and 1.65 µg/g, respectively. Two certified reference materials (IAEA Soil‐7 and IAEA‐405 estuarine sediment) were introduced for the validation of analytical data. The estimated values were compared with other regions of the world and found lower than the world average values, Cd 27% and Pb 13%, and therefore considered comparatively safe and may not be a cause of concern for environmental pollution. Copyright © 2010 Curtin University of Technology and John Wiley & Sons, Ltd.
Effect of bis‐triazoles on a ribose‐based fluorescent sensor
Authors: Huang Huei‐Jyun , Fang Hau‐Yu , Chir Jiun‐Ly , Wu An‐Tai
Published: December 2010

We synthesized two ribosyl‐based fluorescent sensors. Both sensors have an anthracene as the fluorophore, but they differ in the recognition site for metal ions. One (3) has two ribosyl esters, and the other (6) has two triazole groups linked to two ribosyl esters. Among the metal ions examined in MeOH, compound 3 displayed a large chelation‐enhanced fluorescence (CHEF) effect with Hg2+ and Cu2+ ions, and compound 6 displayed a large chelation‐quenched fluorescence (CHQF) effect with Cu2+ and Ni2+ ions. The results demonstrated that the absence (sensor 3) and presence (sensor 6) of an incorporated bis‐triazole group in a ribosyl‐based fluorescent sensor conferred different preferences and distinct binding modes for metal ions. Copyright © 2010 John Wiley & Sons, Ltd.
Cathodic electrochemiluminescent behavior of luminol at nafion–nano‐TiO2 modified glassy carbon electrode
Authors: Ye Ruihong , Huang Lizhang , Qiu Bin , Song Ziwang , Lin Zhenyu , Chen Guonan
Published: December 2010

The electrochemiluminescence (ECL) behavior of luminol on a nafion–nano‐TiO2 modified glassy carbon electrode (nafion–nano‐TiO2GCE) was studied. Two ECL peaks (ECL‐1 and ECL‐2) were found during cathodic potential scanning. ECL‐1 at ca −0.4 V (vs AgAgCl reference electrode) came from the reaction between luminol and active oxygen anion produced at the GCE surface directly, while ECL‐2 at ca −0.9 V (vs AgAgCl reference electrode) came from the reaction between luminol and the active oxygen anion catalyzed by TiO2. The possible mechanism for the generation of both ECL peaks has been proposed. The reproducibility of the ECL intensities on nafion–nano‐TiO2GCE at ECL‐1 and ECL‐2 was good, with relative standard deviations (n = 10) of 4.3 and 1.3%, respectively. The ECL‐2 generated at the nafion–nano‐TiO2GCE surface was further developed to detect the dissolved oxygen, and a detection limit of 0.02 mg/L was achieved. The proposed method was applied to detect dissolved oxygen in water with satisfactory result. Copyright © 2010 John Wiley & Sons, Ltd.
Marrow‐Derived stem cell motility in 3D synthetic scaffold is governed by geometry along with adhesivity and stiffness
Authors: Peyton Shelly R. , Kalcioglu Z. Ilke , Cohen Joshua C. , Runkle Anne P. , Van Vliet Krystyn J. , Lauffenburger Douglas A. , Griffith Linda G.
Published: December 2010

Design of 3D scaffolds that can facilitate proper survival, proliferation, and differentiation of progenitor cells is a challenge for clinical applications involving large connective tissue defects. Cell migration within such scaffolds is a critical process governing tissue integration. Here, we examine effects of scaffold pore diameter, in concert with matrix stiffness and adhesivity, as independently tunable parameters that govern marrow‐derived stem cell motility. We adopted an “inverse opal” processing technique to create synthetic scaffolds by crosslinking poly(ethylene glycol) at different densities (controlling matrix elastic moduli or stiffness) and small doses of a heterobifunctional monomer (controlling matrix adhesivity) around templating beads of different radii. As pore diameter was varied from 7 to 17 µm (i.e., from significantly smaller than the spherical cell diameter to approximately cell diameter), it displayed a profound effect on migration of these stem cells—including the degree to which motility was sensitive to changes in matrix stiffness and adhesivity. Surprisingly, the highest probability for substantive cell movement through pores was observed for an intermediate pore diameter, rather than the largest pore diameter, which exceeded cell diameter. The relationships between migration speed, displacement, and total path length were found to depend strongly on pore diameter. We attribute this dependence to convolution of pore diameter and void chamber diameter, yielding different geometric environments experienced by the cells within. Bioeng. 2011; 108:1181–1193. © 2010 Wiley Periodicals, Inc.
Escherichia coli W as a new platform strain for the enhanced production of L‐Valine by systems metabolic engineering
Authors: Park Jin Hwan , Jang Yu‐Sin , Lee Jeong Wook , Lee Sang Yup
Published: December 2010

A less frequently employed Escherichia coli strain W, yet possessing useful metabolic characteristics such as less acetic acid production and high L‐valine tolerance, was metabolically engineered for the production of L‐valine. The ilvA gene was deleted to make more pyruvate, a key precursor for L‐valine, available for enhanced L‐valine biosynthesis. The lacI gene was deleted to allow constitutive expression of genes under the tac or trc promoter. The ilvBNmut genes encoding feedback‐resistant acetohydroxy acid synthase (AHAS) I and the L‐valine biosynthetic ilvCED genes encoding acetohydroxy acid isomeroreductase, dihydroxy acid dehydratase, and branched chain amino acid aminotransferase, respectively, were amplified by plasmid‐based overexpression. The global regulator Lrp and L‐valine exporter YgaZH were also amplified by plasmid‐based overexpression. The engineered E. coli W (ΔlacI ΔilvA) strain overexpressing the ilvBNmut, ilvCED, ygaZH, and lrp genes was able to produce an impressively high concentration of 60.7 g/L L‐valine by fed‐batch culture in 29.5 h, resulting in a high volumetric productivity of 2.06 g/L/h. The most notable finding is that there was no other byproduct produced during L‐valine production. The results obtained in this study suggest that E. coli W can be a good alternative to Corynebacterium glutamicum and E. coli K‐12, which have so far been the most efficient L‐valine producer. Furthermore, it is expected that various bioproducts including other amino acids might be more efficiently produced by this revisited platform strain of E. coli. Bioeng. 2011; 108:1140–1147. © 2010 Wiley Periodicals, Inc.
Enzyme inactivation by ethanol and development of a kinetic model for thermophilic simultaneous saccharification and fermentation at 50 °C with Thermoanaerobacterium saccharolyticum ALK2
Authors: Podkaminer Kara K. , Shao Xiongjun , Hogsett David A. , Lynd Lee R.
Published: December 2010

Studies were undertaken to understand phenomena operative during simultaneous saccharification and fermentation (SSF) of a model cellulosic substrate (Avicel) at 50°C with enzymatic hydrolysis mediated by a commercial cellulase preparation (Spezyme CP) and fermentation by a thermophilic bacterium engineered to produce ethanol at high yield, Thermoanaerobacterium saccharolyticum ALK2. Thermal inactivation at 50°C, as shown by the loss of 50% of enzyme activity over 4 days in the absence of ethanol, was more severe than at 37°C, where only 25% of enzyme activity was lost. In addition, at 50°C ethanol more strongly influenced enzyme stability. Enzyme activity was moderately stabilized between ethanol concentrations of 0 and 40 g/L, but ethanol concentrations above 40 g/L accelerated enzyme inactivation, leading to 75% loss of enzymatic activity in 80 g/L ethanol after 4 days. At 37°C, ethanol did not show a strong effect on the rate of enzyme inactivation. Inhibition of cellulase activity by ethanol, measured at both temperatures, was relatively similar, with the relative rate of hydrolysis inhibited 50% at ethanol concentrations of 56.4 and 58.7 g/L at 50 and 37°C, respectively. A mathematical model was developed to test whether the measured phenomena were sufficient to quantitatively describe system behavior and was found to have good predictive capability at initial Avicel concentrations of 20 and 50 g/L. Biotechnol. Bioeng. 2011; 108:1268–1278. © 2010 Wiley Periodicals, Inc.
Modeling industrial centrifugation of mammalian cell culture using a capillary based scale‐down system
Authors: Westoby Matthew , Rogers Jameson K. , Haverstock Ryan , Romero Jonathan , Pieracci John
Published: December 2010

Continuous‐flow centrifugation is widely utilized as the primary clarification step in the recovery of biopharmaceuticals from cell culture. However, it is a challenging operation to develop and characterize due to the lack of easy to use, small‐scale, systems that can be used to model industrial processes. As a result, pilot‐scale continuous centrifugation is typically employed to model large‐scale systems requiring a significant amount of resources. In an effort to reduce resource requirements and create a system which is easy to construct and utilize, a capillary shear device, capable of producing energy dissipation rates equivalent to those present in the feed zones of industrial disk stack centrifuges, was developed and evaluated. When coupled to a bench‐top, batch centrifuge, the capillary device reduced centrate turbidity prediction error from 37% to 4% compared to using a bench‐top centrifuge alone. Laboratory‐scale parameters that are analogous to those routinely varied during industrial‐scale continuous centrifugation were identified and evaluated for their utility in emulating disk stack centrifuge performance. The resulting relationships enable bench‐scale process modeling of continuous disk stack centrifuges using an easily constructed, scalable, capillary shear device coupled to a typical bench‐top centrifuge. Bioeng. 2011; 108:989–998. © 2010 Wiley Periodicals, Inc.
Development and validation of an analytical method for determination of endocrine disruptor, 2,4‐D, in paddy field water
Authors: Park Ji‐Yeon , Choi Jeong‐Heui , Abd El‐Aty A. M. , Kim Bo Mi , Park Jong‐Hyouk , Choi Woo Jung , Shim Jae‐Han
Published: December 2010

The acidic herbicides are an important class of chemical compounds that are used to control a variety of weeds that threaten many crops. Owing to their low microbial activity levels, the acidic herbicides exhibit a residual activity remaining for periods of up to several months in soils and water. The principal objective of this study was to develop an analytical method based on liquid–liquid and solid‐phase extraction followed by HPLC, for the determination of 2,4‐D in paddy field water. The residues were verified via tandem mass spectrometry (MS/MS) in negative‐ion electrospray ionization (ESI) mode. Linearity was good over a concentration range of 1–100 µg/L with a correlation coefficient (r2) of 0.999. The mean recovery rates of triplicate results ranged from 85.2 to 90.85%. The limits of detection and quantitation were 0.4 and 1.0 µg/L, respectively. The method proposed herein was applied to field samples acquired from Hampyung and Sunchang counties, Republic of Korea. The analyte was detected at a concentration range of 6.8–12.8 and 3.55–24.0 µg/L, respectively. Copyright © 2010 John Wiley & Sons, Ltd.
In search of the psychopathic sexuality taxon: Indicator size does matter
Authors: Walters Glenn D. , Marcus David K. , Edens John F. , Knight Raymond A. , Sanford Glenn M.
Published: December 2010

Recent research has suggested that a qualitatively distinct subtype of psychopathic sex offender can be identified via taxometric analyses (Harris et al., 2007). In this study we attempted to replicate the hypothesized psychopathic sexuality taxon in a group of 503 male sexual offenders using data from the Psychopathy Checklist‐Revised (PCL‐R: Hare, 2003) and five coercive and precocious sexuality items. Ambiguous to dimensional results were obtained when, in a replication of the Harris et al. (2007) study, dichotomized indicators were analyzed with summed input maximum covariance (MAXCOV). Clearly dimensional results, however, were obtained when higher correlating and more valid quasi‐continuous indicators were analyzed with traditional (input variables not summed) MAXCOV, and both dichotomous and quasi‐continuous indicators were analyzed with mean above minus below a cut (MAMBAC) and latent‐mode factor analysis (L‐Mode). These results suggest that Harris et al. (2007) may have mistaken the random fluctuations of weakly correlating and poorly differentiating indicators for a taxon. Consistent with the vast majority of earlier research, our results suggest that psychopathy (with or without coercive and precocious sexuality) is a dimensional construct. Copyright © 2010 John Wiley & Sons, Ltd.
Autotest: An educational software application to support teachers in creating tests
Authors: Hernández‐Del‐Olmo Félix , Gaudioso Elena
Published: December 2010

In this paper, we present the students' evaluation procedure at the UNED (Spanish Distance Education University). At UNED, students are free to choose the location and the date they take their exams. However, this approach requires that teachers define and develop several exams for every single subject. To ease this task, in this paper we present Autotest, a tool that generates exams in an automatic way. We instantiate this tool for a subject being taught by the authors, Complexity and Computability taught in the third year of the Computer Science studies at UNED. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 636–640, 2013
Adaptive distance learning and testing system
Authors: Marković Suzana , Jovanović Zoran , Jovanović Nenad , Jevremović Aleksandar , Popović Ranko
Published: December 2010

User models are essential to e‐learning systems, giving students learning continuity, tutors evidence of students' progress, and both a way to personalize students' learning materials to their abilities and preferences. Personalizing information has long been the motivation behind developing e‐learning systems. Adaptive educational systems attempt to maintain a learning style profile for each student and use this profile to adapt the presentation and navigation of instructional content to each student. This kind of system adapts the learning process on the basis of the student's learning preferences, knowledge, and availability. One such Web‐based tool is built at the Business School of Professional Studies in Blace (the system of intelligent evaluation using tests), which infers student knowledge using adaptive testing. The knowledge is not evaluated according to fixed standards, but it depends on individual characteristics of each student, therefore, the learning style which is the most suitable. This system is part of the integrated assessment system inside of integrated curriculum. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21:E2–E13, 2013
Analysis and modeling of tutor functions
Authors: Ayachi‐Ghanouchi Sonia , Cheniti‐Belcadhi Lilia , Lewis Robert
Published: December 2010

In distance education and training, tutors play a fundamental role as they act as a facilitator of the learning process, particularly through their evaluation of the progress made. In this paper, we provide an overview of tutoring in e‐learning contexts and describe the main functions that should be assumed by a tutor. We then analyze all activities performed by tutors and establish conceptual models based on the Unified Modeling Language. The models promote an in‐depth analysis and a detailed description of the functions needed to tutor on‐line courses. These models may not only be used as guidelines for tutors but also as a general schema to assess their work. Evaluation and validation of these models have been accomplished by a questionnaire that has been designed and distributed to learners in the framework of a tutored e‐learning experiment. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 657–670, 2013
More carrot than stick: Encouraging computer programming in thermal design projects
Authors: Cole Kevin D.
Published: December 2010

Students will do almost anything to avoid using thermal‐property tables. In this paper, Matlab‐based thermal‐property software is described as an enticement for students to do computer programming in the design of thermal systems. Downloaded shareware was used for steam properties in a steam‐cycle project, and an air‐property package was developed for use with a gas‐turbine project. Although the use of computer programming required considerable effort by both instructor and students, most students did gain a better appreciation of the utility of writing computer programs as part of engineering design. Student evaluations of the course were not significantly affected compared to semesters in which computer programming was not encouraged. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 698–703, 2013
Synthesis of Er2O3 Nanoparticles and Er2O3 Nanoparticle/Polyaniline Deposition on the Surface of Stainless Steel by Potentiostatic Deposition
Authors: Mohammadi A. , Badraghi J. , Moghaddam A. B. , Ganjkhanlou Y. , Kazemzad M. , Hosseini S. , Dinarvand R.
Published: December 2010

Erbium oxide nanoparticles (Er2O3 NP) were synthesized with an efficient method in the presence and absence of sodium dodecylsulfate (SDS) as surfactant. The effect of SDS on the morphology of the synthesized Er2O3 NP is described. The NP were studied through scanning electron microscopy and X‐ray diffractometry. Then, polyaniline and a hybrid material of polyaniline/Er2O3 NP were deposited directly on a stainless steel wire by the potentiostatic process. The electrochemical data and scanning electron microscopic studies of polyaniline and its nanocomposite on the stainless steel wire demonstrate the influence of the synthesized Er2O3 NP on the electrodeposition of polyaniline. The presence of NP in the electrolyte solution during electrodeposition of polyaniline creates a nanocomposite with a more porous structure than pure polyaniline.
Effect of Hydrocarbon and Non‐Hydrocarbon Gas Injection on the Interfacial Tension of a Gas Condensate System
Authors: Al‐Abri A. , Amin R.
Published: December 2010

Experimental results of interfacial tension (IFT) of condensate‐brine‐gas systems over a pressure range of 1000 to 8000 psi and a temperature range of 95 to 160 °C are presented. High‐pressure high‐temperature video‐enhanced pendent drop tensiometry was established to capture drop images for IFT measurements at various reservoir thermodynamic conditions. This paper serves as a building block to the essential practical understanding of the surface effects associated with improved condensate recovery from gas condensate reservoirs by gas injection. This understanding is critical for ascertaining gas injectivity, displacement and trapping in the pore spaces, and potential geological storage of CO2.
Synthesis and Characterization of a Novel Low‐Viscosity Unsaturated Hyperbranched Polyester Resin
Authors: Zhang D. , Wang J. , Li T. , Zhang A. , Jia D.
Published: December 2010

Hyperbranched thermosetting resin is the best additive for toughening and reinforcing linear thermosetting resin. A novel low‐viscosity unsaturated hyperbranched polyester resin (UHPR) is synthesized by the reaction between maleic anhydride monoisooctyl alcohol ester and a hydroxyl‐ended hyperbranched polyester resin (HPR) prepared from phthalic anhydride (PA) and trimethylolpropane (TMP). The structure of HPR is characterized by FT‐IR and 1H NMR, and its degree of branching is deduced by comparing with the 1H NMR spectrum of a model compound. The molecular weights of HPR and UHPR are determined by theoretical calculation and MALDI‐TOF MS measurements. This low‐viscosity (< 10 000 cP) novel UHPR can be applied in the field of environment‐friendly coatings and in toughening and reinforcing linear unsaturated polymers.
Gold Nanoparticle Synthesis, Morphology Control, and Stabilization Facilitated by Functional Polymers
Authors: Alexandridis P.
Published: December 2010

Gold nanoparticles exhibit novel optical and catalytic properties, are nontoxic and biocompatible, and attract considerable interest in a range of applications, e.g. photonics, diagnostics, and therapeutics. The morphology (size and shape) of the nanoparticles and their surface/colloidal properties are very important in the various applications. A methodology for the synthesis in aqueous media of gold nanoparticles with controlled size and shape and exceptional colloidal stability is reviewed. This methodology is based on designer polymers that can exhibit multiple functions on the basis of the polymer intramolecular and supramolecular organization. In addition to being water based, this methodology requires no external energy input and employs commercially available polymers, e.g., poly(ethylene oxide) containing Pluronics or Poloxamers, resulting in low cost and potential environmental benefits.
Multivariate assessment of virtual screening experiments
Authors: Andersson C. David , Chen Brian Y. , Linusson Anna
Published: December 2010

Discovering molecules with a desired biological function is one of the great challenges in drug research. To discover new lead molecules, virtual screens (VS) are often conducted, in which databases of molecules are screened for potential binders to a specific protein, using molecular docking. The choice of docking software and parameter settings within the software can significantly influence the outcome of a VS. In this study, we have applied chemometric methods such as design of experiments, principal component analysis and partial least‐square projections to latent structure (PLS) to simulated VS experiments to find and compare suitable conditions for performing VS against six protein targets selected from the DUD databases. The docking parameters in FRED, and scoring functions in both FRED and GOLD docking software, were varied according to a statistical experimental design and a PLS model was calculated to correlate the experimental setup to the VS outcome. The study revealed that the choice of scoring function has the greatest influence on VS outcome, and that other parameters have varying influence, depending on the protein target. We also found that substantial bias can be introduced by the lack of variation of molecular properties in the databases used in the screening. Our results provide indications that docking experiments could be tailored to the protein target in order to obtain satisfactory VS results. Copyright © 2010 John Wiley & Sons, Ltd.
A graphical index of separation (GIOS) in multivariate modeling
Authors: Eriksson Lennart , Wold Svante
Published: December 2010

We introduce a new measure for the importance of predictor variables, X, for the separation of two groups (classes) of observations. The measure is a Graphical Index of Separation (GIOS), and is, for each predictor, determined from the distribution of all possible pairs of observations with one from each group. GIOS is quantitative, intuitively simple and easy to interpret. The GIOS is straightforward to visualize in bivariate plots, and line or bar plots for larger number of variables. The approach applies both to discriminant analyses such as LDA, SIMCA, PLS‐DA, OPLS‐DA and to quantitative modeling such as MLR, PLS and OPLS. In the latter case, the observations are first divided into two groups based on their response values, Y. The GIOS approach is illustrated by PLS‐DA/OPLS‐DA and SIMCA‐classification of a number of multivariate data sets with few and many variables relative to the number of observations. Copyright © 2010 John Wiley & Sons, Ltd.