bluuebunny/crossref_metadata_2025 huggingface dataset:
Deprotonative Metalation of Aromatic Compounds by Using an Amino‐Based Lithium Cuprate
Authors: Nguyen Tan Tai , Marquise Nada , Chevallier Floris , Mongin Florence
Published: August 2011

Deprotonative cupration of aromatic compounds by using amino‐based lithium cuprates was optimized with 2,4‐dimethoxypyrimidine and 2‐methoxypyridine as the substrates and benzoyl chloride as the electrophile. [(tmp)2CuLi] (+2 LiCl) (tmp=2,2,6,6‐tetramethylpiperidino) was identified as the best reagent and its use was extended to anisole, 1,4‐dimethoxybenzene, other substituted pyridines, furan, thiophene and derivatives, and N‐Boc‐indole (Boc=tert‐butyloxycarbonyl). Of the electrophiles employed to attempt the interception of the generated aryl cuprates, aroyl chlorides, iodomethane, and diphenyl disulfide efficiently reacted. In addition, different oxidative agents were identified to afford symmetrical biaryls. Finally, palladium‐catalyzed coupling with aryl halides was optimized and allowed the synthesis of different aryl derivatives in medium to good yields.
Hydrothermal Carbonization: 1. Influence of Lignin in Lignocelluloses
Authors: Dinjus Eckhard , Kruse Andrea , Tröger Nicole
Published: August 2011

Die hydrothermale Karbonisierung ist ein attraktives Verfahren zur Umwandlung von Biomasse mit hohem Wassergehalt in unterschiedlichste Produkte. Den speziellen Anforderungen an die Produkte, sei es Bodenverbesserer, Braunkohle‐Ersatz oder gar Ersatz für Industrieruß, steht Biomasse als Ausgangsmaterial gegenüber, dessen komplexe Zusammensetzung hochgradig variiert. Ziel der Arbeiten war, den Einfluss von Inhaltsstoffen, hier Lignin, auf die Karbonisierung näher zu untersuchen. Hierbei wird nicht nur die Zusammensetzung sondern auch die Struktur betrachtet.
Current challenges in the design and control of multiscale systems
Authors: Ricardez‐Sandoval Luis A.
Published: August 2011

Multiscale modelling is a new emerging field in process systems engineering. Although the idea of linking events occurring across time and length scales is not new, the numerical solution of these models is challenging because of computational limitations and the difficulty in coupling modelling methods with different characteristics. Although an extensive set of tools are currently available to improve the performance of processes described using continuum models, most of these tools are not suitable to design and control a multiscale process. This work presents the approaches that are currently available to perform multiscale modelling and identifies the key challenges that need to be addressed to improve the performance of macroscopic processes by controlling events occurring at the atomistic, molecular and nanoscopic levels.
Influence of reaction conditions and red brick on fast pyrolysis of rice residue (husk and straw) in a spout‐fluid bed
Authors: Li Rui , Zhong Zhao‐Ping , Jin Bao‐Sheng , Jiang Xiao‐Xiang , Wang Chun‐Hua , Zheng Ai‐Jun
Published: August 2011

Fast pyrolysis of rice residue (husk and straw) was carried out in a spout‐fluid bed. In this study, the effects of reaction conditions (pyrolysis temperature, flow state, feed rate and feed size) and red brick (RB) using as bed material on the pyrolysis product distribution and bio‐oil qualities were investigated. Two phases composed the bio‐oil obtained from fast pyrolysis of rice residue. The results showed that at around 460°C the bio‐oil yields could reach the maxima, which were 48.2% and 53.1% for rice husk and straw respectively. Due to the heat and mass transfer motion, higher yields of bio‐oil and organics in upper phase could be obtained in spout‐fluid state compared with fluid state, which indicated that the spout‐fluid state might be more beneficial for fast pyrolysis. In additional, lower feed rates and larger particle sizes were found unfavourable for the bio‐oil production. The application of RB as bed material instead of quartz sand (QS) resulted in less bio‐oil and char, but more organics in upper phase. Furthermore, the quality of the upper phases was improved by RB, with the characteristics of high heating value and lower water and oxygen contents than QS. © 2011 Canadian Society for Chemical Engineering
Seismic collapse capacity of basic inelastic structures vulnerable to the P‐delta effect
Authors: Adam Christoph , Jäger Clemens
Published: August 2011

The collapse capacity of earthquake‐excited inelastic nondeteriorating SDOF systems, which are vulnerable to the destabilizing effect of gravity loads (P‐delta effect), is evaluated. In this paper, the collapse capacity of the system subjected to a ground motion is defined as spectral acceleration at its initial structural period, at which the structure becomes unstable. Characteristic structural parameters, which affect the collapse capacity, are identified. Ground motion records of the ATC 63 far‐field set characterize severe earthquake excitation. In extensive incremental dynamic analyses studies, the impact of these parameters and of aleatory uncertainties on the collapse capacity is assessed and quantified. Median and percentile collapse capacities are plotted against the initial structural period leading to collapse capacity spectra. Nonlinear regression analyses are applied to derive analytical expressions of the design collapse capacity spectra and collapse fragility curves. The ultimate objective is to provide collapse capacity spectra for easy application and yet sufficient accurate assessment of the dynamic stability of flexible multistory buildings. Copyright © 2011 John Wiley & Sons, Ltd.
Overexpression of apoptosis‐associated speck‐like protein in P388D1 murine lymphoma cells affects metastatic properties
Authors: Zhang Yi , Zhang Jian , Lin Changwei , Wei Wei , Ren Shuangyi , Zuo Yunfei
Published: August 2011

Apoptosis‐associated speck‐like protein (ASC) is a bipartite adaptor molecule that participates in inflammation and apoptosis. ASC silencing has been observed in a significant proportion of human cancers. Here, we examined the role of ASC overexpression in the metastasis of the P388D1 murine lymphoma cell line to the liver, lung, spleen and kidney. First, we determined that the P388D1 cells express ASC. Then, ASC overexpression in P388D1 was achieved by transfecting pEGFP‐ASC‐C2 into the P388D1 cells. Furthermore, after the ASC‐overexpressing P388D1 cells were injected into DBA/2 mice through the vena caudalis, their metastasis to the lung and the liver was significantly reduced in the pEGFP‐ASC‐C2‐transfected group. These data indicate that ASC overexpression affects the in vivo metastatic properties of P388D1 cells. Copyright © 2011 John Wiley & Sons, Ltd.
Serum endostatin levels correlate with enhanced extracellular matrix degradation and poor patients' prognosis in bladder cancer
Authors: Szarvas Tibor , László Viktória , vom Dorp Frank , Reis Henning , Szendröi Attila , Romics Imre , Tilki Derya , Rübben Herbert , Ergün Süleyman
Published: August 2011

Endostatin, the proteolytic fragment of collagen XVIII, is an inhibitor of angiogenesis and tumor growth. Interestingly, elevated circulating endostatin levels have been found to correlate with poor patients' prognosis in several cancers. The aim of this study was to assess the prognostic value of endostatin in bladder cancer (BC) and to gain insight into the mechanisms involved in its production. This retrospective study included a total of 337 patients with BC and 103 controls. Collagen XVIII gene expression was analyzed using real‐time PCR (n = 82). Endostatin tissue localization was assessed by immunohistochemistry (n = 27). Endostatin serum (n = 87) and urine (n = 153) levels were determined by ELISA. In 12 cases, both serum and paraffinized tissue samples from the same patients were available. We found decreased collagen XVIII tissue expression and increased endostatin urine and serum concentration in samples of patients with BC compared to controls. High serum endostatin levels correlated with the presence of lymph node metastases and MMP‐7 concentrations and were independently associated with poor metastasis‐free and disease‐specific survival. Immunohistochemical analysis revealed a strong endostatin staining in the wall of tumor associated blood vessels in superficial but not in muscle‐invasive BCs. Based on these, we concluded that elevated endostatin levels in patients with BC are the consequence of enhanced extracellular matrix degradation and are independent from collagen XVIII expression. Furthermore, serum endostatin levels may provide prognostic information independent from histopathological parameters and may therefore help to optimize therapy decisions. Loss of endostatin expression in tumor associated blood vessels might represent an important step supporting tumor‐induced angiogenesis.
Elucidation of the methyl transfer mechanism catalyzed by chalcone O‐methyltransferase: A density functional study
Authors: Cui Feng‐Chao , Pan Xiao‐Liang , Liu Wei , Liu Jing‐Yao
Published: August 2011

The mechanism of the methyl transfer catalyzed by chalcone O‐methyltransferase has been computationally investigated by employing the hybrid functional B3LYP. Two models are constructed based on the two conformations of the substrate isoliquiritigenin in the X‐ray structure. Our calculations show that the overall reaction is divided into two elementary steps: the water‐assisted deprotonation of the substrate by His278 as a catalytic base, followed by the methyl transfer from S‐adenosyl‐L‐methionine (SAM) to the substrate. The calculated rate‐limiting barriers for the methyl‐transfer step indicate that the catalytic reactions are energetically feasible for both conformations adopted by the substrate. Copyright for JCC Journal: © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
IMPACT OF FARMER FIELD SCHOOLS ON AGRICULTURAL INCOME AND SKILLS: EVIDENCE FROM AN AID‐FUNDED PROJECT IN RURAL ETHIOPIA
Authors: Todo Yasuyuki , Takahashi Ryo
Published: August 2011

This study estimates the effect of farmer field schools in rural Ethiopia on income from agriculture. The farmer field schools were established in association with participatory forest management associations for forest protection funded by Japanese aid. We employ a difference‐in‐differences propensity score matching approach to correct for possible biases due to selection of participants. We find that by participating in the farmer field schools, agricultural households increased their real income per worker by about 60‐160 US dollars in two years on average, which is equivalent to, or even more than, the average income per worker before the project. We also find evidence that the large increase in income is due to the use of new agricultural practices, such as new varieties, taught and promoted in the farmer field schools. Copyright © 2011 John Wiley & Sons, Ltd.
Tracking mesoscale convective systems in the Sahel: relation between cloud parameters and precipitation
Authors: Goyens Clémence , Lauwaet Dirk , Schröder Marc , Demuzere Matthias , Van Lipzig Nicole P. M.
Published: August 2011

Although mesoscale convective systems (MCSs) are the main source of precipitation in the semi‐arid Sahel region, the relationship between MCS characteristics and their generated precipitation remain unclear. However, a thorough understanding of this relation is essential to work towards a classification scheme for MCSs and eventually to improve quantitative precipitation estimates in which cloud parameters are used as proxy variables for the total or maximum intense rainfall from a system. Accordingly, this study aims to analyse the cloud parameters and rain variables distributions and their concurrence before quantifying the relationships between them. This is done using hourly EUMETSAT's Meteosat‐8 infrared (10.8 µm) images, 3‐hourly precipitation data from National Aeronautics and Space Administration (NASA)'s Tropical Rainfall Measuring Mission and an MCS tracking algorithm. The period of interest extends from 1 June till 22 September 2006 and the area of interest covers the Lake Chad region. Results indicate that MCSs in the Sahel region generally show a maximum cloud coverage around 57 000 km2, a life duration of 9 h, an embedded convective core during 6 h and precipitation peaks around 12.3 mm h−1. A recurrent sequence of cloud and rain variables is also noticed; maximum in cloud coverage is mostly preceded by a minimum in brightness temperature in the cold convective core and is followed by a peak in precipitation. Longer‐lived and larger MCSs as well as MCSs embedding very cold and long‐lived convective cores exhibit an increased likelihood to induce more intense precipitation. Focussing on the characteristics of the cold convective core rather than on the characteristics of the entire system appears to be more relevant to predict the precipitation as the former are better correlated with the generated precipitation and can be used as proxy parameter for estimations of maximum intense precipitation using two‐dimensional nonlinear regression models. Copyright © 2011 Royal Meteorological Society
Implant stability in the treatment of MRSA bone implant infections with linezolid versus vancomycin in a rabbit model
Authors: Schroeder Kerstin , Simank Hans‐Georg , Lorenz Helga , Swoboda Stefanie , Geiss Heinrich K. , Helbig Lars
Published: August 2011

The increasing prevalence of methicillin‐resistant Staphylococcus aureus (MRSA) infections represents a significant healthcare burden. Vancomycin and linezolid exhibit potent clinical and microbiological activity in MRSA infections. Our purpose was to investigate the efficacy of linezolid versus vancomycin in experimental implant infections and the influence on implant stability in a rabbit model. Thirty‐six female New Zealand White rabbits received surgical insertion of titanium implants into their distal femurs and were randomly assigned to six groups (A: infected, no treatment; B: infected, vancomycin; C: infected, linezolid; D: no infection, no treatment; E/F: no infection, vancomycin or linezolid, respectively). Antibiotics were administered, and plasma levels determined. Bone‐implant specimens were tested for mechanical stability of fixation. Quantitative histomorphometry of bone and soft tissue was performed using computerized image analysis. Plasma levels of linezolid and vancomycin were within the respective therapeutic ranges. Microbiological analysis of specimens from infected rabbits showed MRSA tissue colonization in all untreated animals, in two of six vancomycin‐treated animals, and in none of the linezolid‐treated animals. Antibiotic treatment improved mechanical stability significantly (p = 0.004) with both vancomycin and linezolid. Mechanical testing correlated with histomorphometry results. A significant negative correlation was found between displacement of the implant and the percentage of calcified tissue around the implant, and a significant positive correlation was found between displacement of the implant and the amount of noncalcified tissue. Our data indicate that both treatment regimens improved implant stability. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:190–195, 2012
Use of near‐infrared spectroscopy to distinguish carbon and nitrogen originating from char and forest‐floor material in soils: usefulness of a genetic algorithm
Authors: Vohland Michael , Michel Kerstin , Ludwig Bernard
Published: August 2011

Several algorithms exist for the calibration procedures of near‐infrared spectra in soil‐scientific studies, but the potential of a genetic algorithm (GA) for spectral feature selection and interpretation has not yet been sufficiently explored. Objectives were (1) to test the usefulness of near‐infrared spectroscopy (NIRS) for a prediction of C and N from char and forest‐floor Oa material in soils using either a partial least squares (PLS) method or a GA‐PLS approach and (2) to discuss the mechanisms of GA feature selection for the examined constituents. Calibration and validation were carried out for measured reflectance spectra in the visible and near‐IR region (400–2500 nm) on an existing set of 432 artificial mixtures of C‐free soil, char (lignite, anthracite, charcoal, or a mixture of the three coals), and forest‐floor Oa material. For all constituents (total C and N, C and N from all coals and from the Oa material, C derived from mixed coal, charcoal, lignite, and anthracite), the GA‐PLS approach was superior over the full‐spectrum PLS method. The RPD values (ratio of standard deviation of the laboratory results to standard error of prediction) ranged from 2.4 to 5.1 in the validation and indicated a better category of prediction for three constituents: “approximate quantitative” instead of a “distinction between high and low” for C derived from mixed coal and “good” instead of “approximate quantitative” for C and N derived from all coals. Overall, this study indicates that the approach using GA may have a greater potential than the PLS method in NIRS.
Cadmium‐ and barium‐toxicity effects on growth and antioxidant capacity of soybean (Glycine max L.) plants, grown in two soil types with different physicochemical properties
Authors: Melo Leônidas Carrijo Azevedo , Alleoni Luís Reynaldo Ferracciú , Carvalho Giselle , Azevedo Ricardo Antunes
Published: August 2011

The pollution of agricultural soils by metals is of growing concern worldwide, and is increasingly subject to regulatory limits. However, the effect of metal pollutants on the responses of plants can vary with soil types. In this study, we examined the growth and antioxidant responses of soybean plants exposed to contrasting soils (Oxisol and Entisol), which were artificially contaminated with cadmium (Cd) or barium (Ba). Cadmium reduced plant growth at concentrations higher than 5.2 mg (kg soil)–1, while Ba only affected plant growth at 600 mg kg–1. Such levels are higher than the limits imposed by the Brazilian environmental legislation. Lipid peroxidation was increased only at a Cd concentration of 10.4 mg kg–1 in the Oxisol, after 30 d of exposure. Twelve superoxide dismutase (SOD; EC 1.15.1.1) isoenzymes were evaluated, most of which were classified as Cu/Zn forms. The SOD activity in the leaves of plants grown in the Oxisol decreased over time, whilst remaining high in the Entisol. Catalase (CAT; EC 1.11.1.6) activity in the leaves exhibited little response to Cd or Ba, but increased over time. Glutathione reductase (GR; EC 1.6.4.2) activity was reduced over time when exposed to the higher Cd concentrations, but increased following Ba exposure in the Oxisol. The enzyme‐activity changes were mainly dependent on soil type, time of exposure and, to a lesser extent, the metal concentration of the soil. Soybean plants grown in a sandy soil with a low buffering capacity, such as Entisol, suffer greater oxidative stress than those grown in a clay soil, such as Oxisol.
Using Moran's I and geostatistics to identify spatial patterns of soil nutrients in two different long‐term phosphorus‐application plots
Authors: Fu Weijun , Zhao Keli , Zhang Chaosheng , Tunney Hubert
Published: August 2011

The spatial variation of soil nutrients especially the soil test phosphorus (STP) in grassland soils is becoming important because of the use of soil‐nutrients information as a basis for policies such as the recently EU‐introduced Nitrates Directive. Up to now, the small‐scale spatial variation of soil nutrients in grassland has not been studied. The main aim of this study was to investigate the spatial patterns of soil nutrients in two grazed grassland plots with a long‐term (38 y) P‐application experiment, in order to better understand the spatial variation of soil nutrients and the correlation among soil nutrients in grasslands. Two small areas (one from a high‐P background and the other from a medium‐P background) were selected. Soil samples (304 per study area) were collected based on a 1 m × 1 m grid system. The samples were analyzed for STP, Mg, K, pH, and lime requirement (LR). The results were analyzed using conventional statistics, Moran's I, geostatistics, and a GIS.

Based on the global Moran's I values, significant positive spatial autocorrelations were found for STP, Mg, pH, and LR in both study areas. Spatial clusters and spatial outliers were detected using the local Moran's I index. Clear linear‐shaped high‐high or low‐low value clusters of the studied variables except K were observed in the study areas due to long‐term usage of machine spreader or other agricultural‐management methods in the past. The corresponding linear patterns were further found in the spatial‐distribution maps. Small spatial patches were found for soil K revealing that it had a random spatial distribution related to the relatively uniform K fertilizer in the study areas. The spatial clusters revealed by local Moran's I were in line with the spatial patterns in the distribution maps.
Near‐infrared spectroscopy for rapid estimation of microbial properties in reclaimed mine soils
Authors: Chodak Marcin
Published: August 2011

Several chemical and microbial properties of mine soils need to be measured for comprehensive assessment of the reclamation success. The objective of this study was to evaluate the ability of NIR spectroscopy to predict organic C (Corg), total N (Nt), and several microbial properties of mine soils reclaimed for forestry. Soils samples (n = 154) were collected at two reclaimed areas in central and S Poland, and their spectra in the NIR region (including the visible range, 400–2500 nm) were recorded. A half of the samples was used to develop calibration equations, and another half was used for validation. The modified partial least squares regression was applied to build calibration equations using the whole spectrum (0 to 2nd derivative). The best predictions were obtained for Corg and Nt (ratio of standard deviation to standard error of prediction in the validation stage [RPD] = 3.4 and 4.1; the regressions coefficients [a] of linear regression [measured against predicted values] = 0.94 and 0.96; correlation coefficients [r] = 0.96 and 0.97, respectively). Very well predictive models applicable for quantitative measurements were obtained also for microbial biomass, basal respiration, and the activities of dehydrogenase and acid phosphatase (RPD = 2.3–2.5, a = 0.90–0.99, r = 0.90–0.92). Prediction of urease activity was slightly worse (RPD = 2.1, a = 0.88, r = 0.87) but sufficient for rough estimation. The obtained results indicated the ability of NIR spectroscopy to predict complex soil microbial properties. Therefore, application of this analytical method may improve the assessment of recovery of microbial functions in reclaimed post‐mining barrens.
Effects of lignin‐modified Populus tremuloides on soil organic carbon
Authors: Roque‐Rivera Raysa , Talhelm Alan F. , Johnson Dale W. , Chiang Vincent L. , Pregitzer Kurt S.
Published: August 2011

Several genes in the aspen genome have been modified to generate stem wood with lower lignin content and an altered lignin composition. Lower lignin in wood reduces the time and energy required for pulping. Further, this modification can also increase the allocation of photosynthate to cellulose and total biomass production, potentially increasing CO2‐sequestration capacity. However, widespread planting of trees with altered lignin content and composition could alter soil organic‐C dynamics in complex ways. To further examine the effects of altered lignin biosynthesis on plant growth and accrual of soil organic C (SOC), we conducted a repeated greenhouse study with four lines of transgenic aspen (Populus tremuloides Michx.) and one wild‐type (control) aspen. Accrual of aspen‐derived SOC was quantified by growing aspen trees (C3 plants) in C4 soil and measuring changes in the natural abundance of δ13C. We measured plant growth, biomass, and C content and combined these data with SOC measurements to create C budgets for the plant mesocosms. Lignin modifications resulted in differences in the accrual of aspen‐derived SOC and total mesocosm C, primarily due to differences in biomass between genetically modified lines of aspen. One genetic alteration (low lignin, line 23) was able to perform similarly or better than the wild‐type aspen (control, line 271) without altering SOC. Alterations in lignin structure (S : G ratios) had negative effects on biomass production and SOC formation. The addition of new (aspen‐derived) SOC was proportional to the loss of existing SOC, evidence for a priming effect. The pool of new SOC was related to total plant biomass, suggesting that the effects of lignin modification on SOC are driven by changes in plant growth.
Developing Interpretation Plans to Promote Traditional Rural Buildings as Built Heritage Attractions
Authors: Porto Simona M. C. , Leanza Paola M. , Cascone Giovanni
Published: August 2011

The present study suggests an innovative method that could be applied by local authorities to develop heritage interpretation plans aimed at promoting traditional rural buildings (TRBs) as built heritage attractions, while preserving their original features. Cultural heritage interpretation (CHI) methods and tools were used. They offer the advantage to create a kind of ‘understanding’ that would lead tourists and local communities to protect TRBs from inappropriate alterations and modifications that often occur when TRBs are reused also for tourism purposes.

The proposed method was applied to TRBs located in an area of the South‐Eastern Sicily (Italy). Copyright © 2011 John Wiley & Sons, Ltd.
Effects of outdoor advertising: Does location matter?
Authors: Wilson Rick T. , Till Brian D.
Published: August 2011

The growth and success of outdoor advertising is in large part due to the medium's ability to reach an increasingly elusive and mobile consumer. However, this success has come with a price. Public pressure and regulation have begun to eliminate or curtail many outdoor advertising locations, leading practitioners to question the effectiveness of the remaining outdoor advertising sites. Using associative learning techniques, these studies investigate what effect, if any, the environment in which outdoor advertising appears has on the attitudes, beliefs, and purchase intent of the advertised brand. The results of four experiments presented here suggest that the background environment does not impact advertising effectiveness, and practitioner concern of such may be unfounded. © 2011 Wiley Periodicals, Inc.
Happiness as a predictor of service quality and commitment for utilitarian and hedonic services
Authors: Hellén Katarina , Sääksjärvi Maria
Published: August 2011

In services research, little attention has been devoted to long‐term intrinsic personality traits. Long‐term personality traits predict short‐term affective states and thus understanding them is important from a service standpoint. Further, identifying long‐term personality traits facilitates the targeting of customers who are predisposed to evaluate services in a positive manner. This study focuses on one long‐term affective trait, happiness, and examines its impact on service evaluation and commitment, as it has been shown that the level of happiness affects whether people perceive life events, both great and small, in a positive or negative manner. Three studies were conducted to research the issue. The first study shows that customers who are happier evaluate service quality in utilitarian services in a more positive manner than do customers who are less happy. The second study shows that for hedonic services, involvement serves as an antecedent to perceived service quality; happier customers are also more involved in hedonic services, and thus perceive service quality in a more positive manner. Study 3 examines the link between happiness and commitment and shows that customers who are happier are also more prone to be committed to hedonic services. These results contribute to the marketing literature by showing that customers are predisposed to evaluate service quality in line with their level of happiness in the case of both utilitarian and hedonic services. Thus, marketing scholars and practitioners ought to recognize that service quality and commitment are partially predetermined by the personality of the customer and that some customers are more difficult to please than others. © 2011 Wiley Periodicals, Inc.
Optimization of Structure Based Virtual Screening Protocols Against Thymidine Monophosphate Kinase Inhibitors as Antitubercular Agents
Authors: Ul‐Haq Zaheer , Uddin Reaz , Gul Sana
Published: August 2011

Thymidine monophosphate kinase from Mycobacterium tuberculosis (TMPKMtub) is an established drug target against tuberculosis. The enzyme TMPKMtub is responsible for the survival of bacterium MTB and required to synthesize an essential building block of the bacterial DNA which is thymidine triphosphate (TTP). There are several potent inhibitors available against the target enzyme but the majority are substrate analogues. Recently, three dimensional structures of the enzyme TMPKMtub inhibitor complexes were resolved using X‐ray crystallography. These available crystal structures were the basis of initiating a structure based lead identification campaign against TMPKMtub. The available information was utilized to perform structure‐based virtual screening against TMPKMtub with the hope to diversify the structures of the current inhibitors. In order to setup the protocol, 10 000 out of 45 000 drug‐like molecules were randomly selected from National Cancer Institute’s (NCI) database. Additionally 105 known inhibitors along with 11 natural substrates were mixed with the 10 000 selected compounds. For the current study, a rigid based docking algorithm, i.e., FRED has been utilized to set up an efficient docking and scoring protocol. The methods including enrichment curves, consensus scoring and ROC curves are providing useful insights into the setting up of a suitable structure‐based docking protocol against TMPKMtub. As a result, an optimum docking and scoring function has been identified for future large scale virtual screening. In the present work, we have demonstrated a rational choice of protocol for structure based virtual screening of chemical libraries and help to understand the influence of receptor flexibility by using multiple geometries.
Coenzyme Q10 suppresses oxLDL‐induced endothelial oxidative injuries by the modulation of LOX‐1‐mediated ROS generation via the AMPK/PKC/NADPH oxidase signaling pathway
Authors: Tsai Kun‐Ling , Chen Li‐Hsin , Chiou Shih‐Hwa , Chiou Guang‐Yuh , Chen Yu‐Chih , Chou Hsiang‐Yun , Chen Liang‐Kung , Chen Hsiao‐Yun , Chiu Tsan‐Hung , Tsai Chiou‐Sheng , Ou Hsiu‐Chung , Kao Chung‐Lan
Published: August 2011

Scope: The lectin‐like oxidized low‐density lipoprotein receptor (LOX‐1) is one pivot receptor for oxidized low‐density lipoprotein (oxLDL) in human endothelial cells. Co‐enzyme Q10 (Co Q10) has been widely used in clinical intervention. However, the molecular mechanisms underlying its protective effects against oxidative stress in endothelial cells are still largely unknown. This study was designed to test the hypothesis that Co Q10 mitigates oxLDL‐induced endothelial oxidative injuries via modulation of LOX‐1‐mediated reactive oxygen species (ROS) generation and explored the role of AMP‐activated protein kinase (AMPK), a negative regulator of NADPH oxidase.

Methods and results: Human umbilical vein endothelial cells (HUVECs) were pretreated with Co Q10 and then incubated with oxLDL for 24 h. Co Q10 attenuated oxLDL‐elicited LOX‐1 expression and ROS generation by suppression of NADPH oxidase activation. Co Q10 rescued dephosphorylation of AMPK caused by oxLDL that in turn led to an activation of NADPH oxidase by PKC. The results were confirmed using AMPK siRNA. Moreover, oxLDL‐suppressed Akt/eNOS and enhanced p38 phosphorylation, which in turn activated NF‐κB pathway. These detrimental events were ameliorated by Co Q10.

Conclusion: These results provide new highlight onto the possible molecular mechanisms of how Q10 suppresses oxLDL‐induced endothelial oxidative injuries by the modulation of LOX‐1‐mediated ROS generation via the AMPK/PKC/NADPH oxidase signaling pathway.
The effects of acrolein on the thioredoxin system: Implications for redox‐sensitive signaling
Authors: Myers Charles R. , Myers Judith M. , Kufahl Timothy D. , Forbes Rachel , Szadkowski Adam
Published: August 2011

The reactive aldehyde acrolein is a ubiquitous environmental pollutant and is also generated endogenously. It is a strong electrophile and reacts rapidly with nucleophiles including thiolates. This review focuses on the effects of acrolein on thioredoxin reductase (TrxR) and thioredoxin (Trx), which are major regulators of intracellular protein thiol redox balance. Acrolein causes irreversible effects on TrxR and Trx, which are consistent with the formation of covalent adducts to selenocysteine and cysteine residues that are key to their activity. TrxR and Trx are more sensitive than some other redox‐sensitive proteins, and their prolonged inhibition could disrupt a number of redox‐sensitive functions in cells. Among these effects are the oxidation of peroxiredoxins and the activation of apoptosis signal regulating kinase (ASK1). ASK1 promotes MAP kinase activation, and p38 activation contributes to apoptosis and a number of other acrolein‐induced stress responses. Overall, the disruption of the TrxR/Trx system by acrolein could be significant early and prolonged events that affect many aspects of redox‐sensitive signaling and oxidant stress.
Two‐step anomalous diffusion tensor imaging
Authors: Hall Matt G. , Barrick Thomas R.
Published: August 2011

We extend the formalism of anomalous diffusion imaging to include directional anisotropy of fitted parameters. The resulting technique is termed anomalous diffusion tensor imaging (aDTI), and allows the directional properties of the distributed diffusion coefficient (α) and the anomalous diffusion exponent, (γ) to be analysed using the same analytical techniques as regular diffusion tensor imaging (DTI). Together, these parameters quantify the rate of diffusion (α) and the complexity of the diffusion environment (γ).

We generated tensor images for the anomalous exponent tensor (Γ) and distributed diffusivity tensor (A) from in vivo human brain data and present images of eigenvalues, eigenvectors, Trace/3 (Tr), fractional anisotropy (FA) and tensor shape measures. In white matter, A is found to have a median Tr = 0.56 × 10− 3mm2s− 1, FA = 0.58 and Γ Tr = 0.69, FA = 0.13.

We observed that white matter shows a similar anisotropic geometry for the distributed diffusion tensor as for the regular diffusion tensor, whereas the anomalous exponent tensor exhibits a different shape characteristic which may be informative of tissue microstructure. Copyright © 2011 John Wiley & Sons, Ltd.
The semantics of alarm definitions: enabling systematic reasoning about alarms
Authors: Wallin Stefan , Leijon Viktor , Nordlander Johan , Bystedt Nicklas
Published: August 2011

The development and integration of an alarm interface between network elements and a network management system is a costly process, largely because of the informal way in which alarm interfaces are expressed and communicated. Low‐quality alarm documentation and confusion around fundamental concepts like alarm states and alarm types are typical consequences of current practices. If alarm interfaces were expressed in a more formal manner, costs could be reduced and more advanced analysis and automation would be enabled. We present a novel approach to alarm interfaces by providing a formal alarm model together with a domain‐specific language that allows us to specify both the alarm models and the constraints placed on the alarm models in a consistent manner. This means that we can verify the consistency of an alarm interface and automatically generate artifacts such as alarm correlation rules or alarm documentation based only on the model. Copyright © 2011 John Wiley & Sons, Ltd.
Hsa‐miR‐375 is differentially expressed during breast lobular neoplasia and promotes loss of mammary acinar polarity
Authors: Giricz Orsi , Reynolds Paul A , Ramnauth Andrew , Liu Christina , Wang Tao , Stead Lesley , Childs Geoffrey , Rohan Thomas , Shapiro Nella , Fineberg Susan , Kenny Paraic A , Loudig Olivier
Published: August 2011

Invasive lobular carcinoma (ILC) of the breast, characterized by loss of E‐cadherin expression, accounts for 5–15% of invasive breast cancers and it is believed to arise via a linear histological progression. Genomic studies have identified a clonal relationship between ILC and concurrent lobular carcinoma in situ (LCIS) lesions, suggesting that LCIS may be a precursor lesion. It has been shown that an LCIS diagnosis confers a 15–20% risk of progression to ILC over a lifetime. Currently no molecular test or markers can identify LCIS lesions likely to progress to ILC. Since microRNA (miRNA) expression changes have been detected in a number of other cancer types, we explored whether their dysregulation might be detected during progression from LCIS to ILC. Using the Illumina miRNA profiling platform, designed for simultaneous analysis of 470 mature miRNAs, we analysed the profiles of archived normal breast epithelium, LCIS lesions found alone, LCIS lesions concurrent with ILC, and the concurrent ILCs as a model of linear histological progression towards ILC. We identified two sets of differentially expressed miRNAs, the first set highly expressed in normal epithelium, including hsa‐miR‐224, ‐139, ‐10b, ‐450, 140, and ‐365, and the second set up‐regulated during lobular neoplasia progression, including hsa‐miR‐375, ‐203, ‐425‐5p, ‐183, ‐565, and ‐182. Using quantitative RT‐PCR, we validated a trend of increasing expression for hsa‐miR‐375, hsa‐miR‐182, and hsa‐miR‐183 correlating with ILC progression. As we detected increased expression of hsa‐miR‐375 in LCIS lesions synchronous with ILC, we sought to determine whether hsa‐miR‐375 might induce phenotypes reminiscent of lobular neoplasia by expressing it in the MCF‐10A 3D culture model of mammary acinar morphogenesis. Increased expression of hsa‐miR‐375 resulted in loss of cellular organization and acquisition of a hyperplastic phenotype. These data suggest that dysregulated miRNA expression contributes to lobular neoplastic progression. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Direct access midwifery booking for prenatal care and its role in Down syndrome screening
Authors: Nawaz Tariq S. , Tringham Gillian M. , Holding Stephen , McFarlane Jane , Lindow Stephen W.
Published: August 2011

Objective

To compare the uptake of Down syndrome screening by women following referral by direct access and general practitioner (GP) modes.

Methods

The method of referral by either GP or direct access, for women who booked into prenatal care in Hull and East Yorkshire in 2010, was analysed using data collected from the Protos database at the Women and Children's Hospital, Hull. Subsequently, the uptake of first and second trimester screening for Down syndrome was reviewed by combining the Protos database to the screening data collected by the Clinical Biochemistry Laboratory at Hull Royal Infirmary, Hull.

Results

Women booked into prenatal care significantly earlier when referred by GP in comparison to direct access with a significant difference in screening uptake of 49.5 and 42.7%, respectively. The ratio of uptake between first and second trimester screening was not significantly different.

Conclusions

Further research on the new direct access method of referral is required, as it may have a role in the uptake of prenatal screening for Down syndrome. More time is needed to show a definitive effect. Copyright © 2011 John Wiley & Sons, Ltd.
Characterization of rigid polypropylene‐based microcellular foams produced by batch foaming processes
Authors: Velasco José Ignacio , Antunes Marcelo , Realinho Vera , Ardanuy Mónica
Published: August 2011

The properties of polypropylene (PP) foams can be extended by controlling the cellular structure and adding functional fillers. PP‐based microcellular foams having an interesting combination of mechanical and transport properties were prepared by two different batch foaming processes. The batch processes employed were a semisolid state CO2 dissolution physical foaming process and a chemical one based on the dissolution of the gases generated by the thermal decomposition of a chemical blowing agent in the molten state. The role of the cellular structure and nanofillers (5 wt% of organoclay and 10–20 wt% of cellulosic fibers) on the foam properties and CO2 diffusion rate was discussed. Foams with expansion ratios around 3 but different cell structures were prepared and studied concerning their structural characteristics. For unfilled foams prepared by CO2 dissolution, the microcellular structure resulted in the highest values of the specific storage modulus. A fraction of organically‐treated montmorillonite dispersed into the PP matrix resulted in superior mechanical properties due to the combined effect of a finer cell structure and inherent higher stiffness of the silicate layers. Despite displaying an open‐cell structure, foams reinforced with high contents of cellulosic fibers showed increased specific storage moduli with respect to the unfilled foams. POLYM. ENG. SCI., 2011. ©2011 Society of Plastics Engineers
Plasticizer migration from cross‐linked flexible PVC: Effects on tribology and hardness
Authors: Ambrogi Veronica , Brostow Witold , Carfagna Cosimo , Pannico Marianna , Persico Paola
Published: August 2011

Uses of flexible poly(vinyl chloride) (PVC) are restricted by plasticizer migration affecting material properties. Moreover, the use of phthalate‐based plasticizers is being questioned worldwide because of their potential toxicity to humans and environment. Chemical modification of PVC structure is one of the most effective tools for reduction of plasticizer diffusion. In this work, a flexible dry blend based on cross‐linked PVC was obtained using a difunctional amine, namely isophoron diamine (IPDA) as the cross‐linking agent. The gel fraction was evaluated from insoluble portions obtained by means of solvent extraction; the efficiency of cross‐linking in reducing the plasticizer leaching was evaluated by migration tests. Effects of addition of IPDA on PVC thermal stability were determined by thermogravimetric analysis (TGA). The cross‐linking reaction turned out to be responsible for accelerating thermal degradation. Tribological properties of flexible uncross‐linked, cross‐linked and rigid PVC were determined. Flexible formulations were held in contact for 32 days with rigid PVC sheets. Plasticizer migration towards the interface caused an increase of dynamic friction compared to that of the reference rigid PVC.Vickers microhardness hVickers values of rigid PVC sheets decreased due to plasticizer surface absorption. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Thermal and combustion behavior of ethylene‐vinyl acetate/aluminum trihydroxide/Fe‐montmorillonite composites
Authors: Chen Xilei , Jiao Chuanmei , Zhang Jun
Published: August 2011

The flammability characterization and synergistic flame‐retardant effect of Fe‐montmorillonite (Fe‐OMT) in the ethylene‐vinyl acetate/aluminum hydroxide (EVA/ATH) compounds were studied using limiting oxygen index (LOI), UL‐94 test, cone calorimeter, microscale combustion calorimetry (MCC), and thermogravimetric analysis (TGA). The results showed that addition of Fe‐OMT increases the LOI value and improves the UL 94 rating. Cone calorimeter data indicate that the addition of Fe‐OMT greatly reduced the heat release rate and carbon monoxide production rate. Furthermore a compact char residue formed on the surface of the sample with a suitable of Fe‐OMT during the combustion. The MCC results indicate that addition of Fe‐OMT reduced the heat release rate and catalyzed the decomposition of EVA. The TGA data showed further evidence that Fe‐OMT can catalyze carbonization reactions. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Synthesis and characterization of water‐dispersible, superparamagnetic single‐wall carbon nanotubes decorated with iron oxide nanoparticles and well‐defined chelating diblock copolymers
Authors: Papaphilippou Petri , Turcu Rodica , Krasia‐Christoforou Theodora
Published: August 2011

A novel approach for the fabrication of magneto‐active carbon nanotubes (CNTs) stabilized in aqueous media, involving the combination of carboxylated single‐wall carbon nanotubes (SWCNTs) with a new class of methacrylate‐based chelating diblock copolymers, is described. More precisely, a well‐defined diblock copolymer consisting of hexa(ethylene glycol) methyl ether methacrylate (hydrophilic and thermo‐responsive) and 2‐(acetoacetoxy)ethyl methacrylate (hydrophobic and metal‐chelating) synthesized by reversible addition‐fragmentation chain transfer polymerization has been used to prepare polymer‐coated magneto‐active SWCNTs decorated with iron oxide nanoparticles. Further to the characterization of the compositional and thermal properties using transmission electron microscopy, Fourier transform infrared spectroscopy, X‐ray diffraction spectroscopy and thermal gravimetric analysis, assessment of the magnetic characteristics by vibrational sample magnetometry disclosed superparamagnetic behavior at room temperature. The latter, combined with the thermo‐responsive properties of the polymeric coating and the unique, inherent properties of the carbon nanotubes may allow for their future exploitation in the biomedical field. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 49: 1389–1396, 2011
Investigation of Adhesion Between Metal and Plasma‐Modified Polyethylene
Authors: Horakova Marta , Spatenka Petr , Hladik Jan , Hornik Jakub , Steidl Josef , Polachova Alena
Published: August 2011

The polyethylene (PE) coatings could be very promising for various branches of industry due to their chemical stability and impact resistance. Plasma modification of powder has recently attracted much interest because of new prospects to control the interfacial properties. Plasma modification also significantly enhanced the adhesion of the polymer to the substrate. Powders find wide application in various branches of industry like paintings, biotechnology, filling for composite materials etc., but the plasma modification of powder surface has not found such application as plasma modification of flat solid materials. This is due to problems connected with the three dimensional geometry, necessity of solid mixing (due to the aggregation phenomenon) and the large surface area of powders which should be treated. We investigated plasma modification of PE powder, its adhesion properties on steel surface and mechanism influencing this adhesion. PE powder was modified using various working gases and chemicals. It was found that adhesion properties were strongly influenced by concentration of oxygen containing groups and also by PE crosslinking after modification. The value of crosslinking depends on used working gas and chemicals. The ternary mixture of O2/H2O/methanol was found to be an appropriate working gas for plasma treatment of PE for adhesion purposes. The treated PE had good wettability, low crosslinking and very high adhesion to the steel substrate.

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