bluuebunny/crossref_metadata_2025 huggingface dataset:
The Roles of Angiogenesis in Malignant Melanoma: Trends in Basic Science Research over the Last 100 Years
Authors: Dewing D. , Emmett M. , Pritchard Jones R.
Published: June 2012

Blood vessels arose during evolution carrying oxygen and nutrients to distant organs via complex networks of blood vessels penetrating organs and tissues. Mammalian cells require oxygen and nutrients for survival, of which oxygen has a diffusion limit of 100 to 200 μm between cell and blood vessel. For growth beyond this margin, cells must recruit new blood vessels, first by vasculogenesis, where embryonic vessels form from endothelial precursors, then angiogenesis which is the sprouting of interstitial tissue columns into the lumen of preexisting blood vessels. Angiogenesis occurs in many inflammatory diseases and in many malignant disease states, including over 90% of solid tumours. Malignant melanoma (MM) is the most lethal skin cancer, highly angiogenic, highly metastatic, and refractory to all treatments. Raised serum levels of vascular endothelial growth factor (VEGF) strongly correlate MM disease progression and poor prognosis. Melanoma cells secrete several proangiogenic cytokines including VEGF-A, fibroblast growth factor (FGF-2), platelet growth factor (PGF-1), interleukin-8 (IL-8), and transforming growth factor (TGF-1) that modulate the angiogenic switch, changing expression levels during tumour transition from radial to invasive vertical and then metastatic growth. We highlight modern and historical lines of research and development that are driving this exciting area of research currently.
Inferring Biologically Relevant Models: Nested Canalyzing Functions
Authors: Hinkelmann Franziska , Jarrah Abdul Salam
Published: June 2012

Inferring dynamic biochemical networks is one of the main challenges in systems biology. Given experimental data, the objective is to identify the rules of interaction among the different entities of the network. However, the number of possible models fitting the available data is huge, and identifying a biologically relevant model is of great interest. Nested canalyzing functions, where variables in a given order dominate the function, have recently been proposed as a framework for modeling gene regulatory networks. Previously, we described this class of functions as an algebraic toric variety. In this paper, we present an algorithm that identifies all nested canalyzing models that fit the given data. We demonstrate our methods using a well-known Boolean model of the cell cycle in budding yeast.
Aqueous Photo-Living Radical Polymerization of Sodium Methacrylate Using a Water-Soluble Nitroxide Mediator
Authors: Yoshida Eri
Published: June 2012

The aqueous photo-living radical polymerization of sodium methacrylate (NaMA) was attained using 2,2′-azobis2-methyl-N-[1,1-bis(hydroxymethyl)-2-hydroxyethyl]-propionamide (V-80) as the initiator and 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (HTEMPO) as the mediator in the presence of (4-fluorophenyl)diphenylsulfonium triflate (FS). The polymerization was carried out in water at room temperature by irradiation using a high-pressure mercury lamp. Whereas the polymerization by V-80 and/or FS in the absence of HTEMPO produced polymers with very high molecular weights and broad molecular weight distributions, the HTEMPO-mediated polymerization provided still lower-molecular-weight distributions using both V-80 and FS. The first-order time-conversion plots had an induction period up to 2.5 h; however, they thereafter showed a linear increase. The conversion-molecular weight plots also exhibited a linear correlation. A linear correlation was also obtained for the plots of the molecular weights versus the reciprocal of the initiator concentration. Based on these three correlations, it was found that the HTEMPO-mediated photopolymerization proceeded by a living mechanism.
Degradation Kinetics of Fe-EDTA in Hydrogen Sulfide Removal Process
Authors: Saelee R. , Bunyakan C.
Published: June 2012

Available data on the degradation of Fe-EDTA liquid redox H2S removal processes are reviewed, and the effect of H2S molar flow rate, the initial concentration of Fe(III)EDTA, and the presence of sodium citrate in Fe-EDTA solution were investigated in this study. The semibatch with continuous flow of H2S containing biogas was used under a wide range of experimental conditions; , H2S molar flow rate, (1.08 × 10−3–3.40 × 10−3 mol/h), the initial concentration of Fe(III)EDTA, (2.17–8.16 mol/m3), and the concentration of sodium citrate, (0–300 mol/m3). The result showed that sodium citrate acted as stabilizer with a good ability to reduce the degradation rate. The degradation rate of Fe-EDTA was found to follow pseudo first-order kinetics. Empirical correlations expressed the degradation rate constant as a function of significant H2S molar flow rate, and the initial Fe(III)EDTA and sodium citrate concentration were successfully developed for the prediction of Fe-EDTA degradation rate. Moreover, the precipitated solid, called sulfur cake, was recovered, and its composition was investigated. The result revealed that the sulfur cake contained more than 98% sulfur element and almost balances with iron, and no significant EDTA was degraded into the solid form.
Renal Cell Carcinoma Update: News from the AUA, EAU, and ASCO Annual Meetings 2011
Authors: Schrader Andres Jan , Steffens Sandra
Published: June 2012

Renal cell carcinoma (RCC) is one of the most important urologic malignancies with a continuously growing incidence and health economic relevance. In 2011, several hundred articles, abstracts, and lectures have been presented at the leading global urooncologic congresses. This review was composed to give an overview on the flood of novel findings dealing with diagnostics and therapy of both localized and advanced RCC. The most clinically relevant data are discussed in detail.
Modified PWM Technique for Harmonic Reduction
Authors: Hoseinpour Alireza , Ghazi Reza
Published: June 2012

This paper presents a Shunt Active Filter (SAF) based on the Variable Index Pulse Width Modulation approach. In the proposed method of Pulse Width Modulation (PWM), the triangular wave is derived by integration of the reference signals. This method introduces two basic advantages; the first one is that the triangular signal contains the information of the signal to be obtained in output and the second advantage is that its amplitude is varied in proportion to the amplitude of the reference signal. Therefore, in this PWM method, the modulation index is varied according to the variation of the reference signal, so it is termed as Variable Index Pulse Width Modulation. In order to demonstrate the validity of the proposed method, the obtained simulation results are compared with results of the Space Vector Modulation (SVM) approach. Furthermore, it is shown that in the case of nonsinusoidal voltages, the SAF with the proposed control strategy can provide the filtering action. This method is quite easy to implement and requires lower circuitry. The results show that the proposed method can satisfy the IEEE-519 standard regarding the reduction of harmonics.
Colorectal Cancer in Northwestern Iran
Authors: Mahmodlou Rahim , Mohammadi Payvand , Sepehrvand Nariman
Published: June 2012

Background. Colorectal cancer is the third most prevalent cancer worldwide, which is less common in the Middle East; its prevalence demonstrated to be 7 persons per 100,000 populations in Iran. In this study, we aimed to investigate the clinicopathologic features of CRC patients in West Azerbaijan province of Iran. Methods. In this crosssectional study, 546 patients who underwent surgical procedures with the pathologic diagnosis of colorectal cancer in both academic and private hospitals of Urmia were enrolled. Results. The mean age at diagnosis was 55.2 ± 11.5 years. 23% had an age lower than forty years old. Rectal bleeding (26%), abdominal pain (25%), and large bowel obstruction (23%) were three most common presenting symptoms. 26% of patients presented with acute abdomen. 95% of tumors were adenocarcinoma, 4% were lymphoma, and 1% was other rare tumors. Regarding the stage of cancer according to TNM staging system, 6% of patients were in stage I, followed by 37% in stage II, 33% in stage III, and 24% in stage IV. In 44.5% of patients, the tumor was located in rectum. Conclusion. In west Azerbaijan province of Iran, patients with colorectal cancer present in younger age and more advanced stages in comparison with the developed countries.
Determination of Some Trace Elements in Food and Soil Samples by Atomic Absorption Spectrometry After Coprecipitation with Holmium Hydroxide
Authors: Saracoglu Sibel , Soylak Mustafa , Çabuk Dilek , Topalak Zeynep , Karagozlu Yasemin
Published: June 2012

The determination of trace elements in food and soil samples by atomic absorption spectrometry was investigated. A coprecipitation procedure with holmium hydroxide was used for separation- preconcentration of trace elements. Trace amounts of copper(II), manganese(II), cobalt(II), nickel(II), chromium(III), iron(III), cadmium(II), and lead(II) ions were coprecipitated with holmium hydroxide in 2.0 M NaOH medium. The optimum conditions for the coprecipitation process were investigated for several commonly tested experimental parameters, such as amount of coprecipitant, effect of standing time, centrifugation rate and time, and sample volume. The precision, based on replicate analysis, was lower than 10% for the analytes. In order to verify the accuracy of the method, the certified reference materials BCR 141 R calcareous loam soil and CRM 025-050 soil were analyzed. The procedure was successfully applied for separation and preconcentration of the investigated ions in various food and soil samples. An amount of the solid samples was decomposed with 15 mL concentrated hydrochloric acid–concentrated nitric acid (3 + 1). The preconcentration procedure was then applied to the final solutions. The concentration of trace elements in samples was determined by atomic absorption spectrometry.
Quantitative Determination of Prednisone in Tablets by Infrared Attenuated Total Reflection and Raman Spectroscopy
Authors: Mazurek Sylwester , Szostak Roman
Published: June 2012

The quantification of prednisone in tablets was performed using partial least squares (PLS) models based on FTIR-attenuated total reflection (ATR) and FT-Raman spectra. To compare the predictive ability of these models, the relative standard error of prediction (RSEP) values were calculated. In the case of prednisone determination from the FT-Raman data, RSEP values of 3.1 and 3.2% for the calibration and validation data sets were obtained. For FTIR-ATR models, which were constructed using five spectra for each sample, these errors amounted to 2.6 and 2.9%, respectively. Four commercial products containing 1, 5, 10, and 20 mg prednisone/tablet were quantified. Concentrations derived from the elaborated models correlated strongly with the results of reference analyses and with the declared values (in parentheses). The analyses gave recoveries of 100.0–101.6% (100.1–103.0%) and 98.1–103.2% (100.4–102.9%) for FTIR-ATR and FT-Raman data, respectively. A successful quantification of prednisolone in tablets containing 5 mg active ingredient/tablet was also performed using the PLS model, which was based on FTIR-ATR spectra, with a recovery of 99.8 (98.8%). Both reported spectroscopic techniques can be used as fast and convenient alternatives to the standard pharmacopeial methods of prednisone and prednisolone quantification in solid dosage forms. However, in the case of FTIR-ATR spectroscopy, it is necessary to repeat measurements several times to obtain sufficiently low quantification errors.
Development and Optimization of an HPLC Analysis of Citalopram and Its Four Nonchiral Impurities Using Experimental Design Methodology
Authors: Tadić Svetlana , Nikolić Katarina , Agbaba Danica
Published: June 2012

In this study, the RP-HPLC method was investigated for the separation of citalopram and its four impurities by use of statistical experimental design. Initially, the influence of different experimental conditions (buffer pH, flow rate, and column temperature) on the chromatographic behavior of citalopram and its four impurities was investigated by use of partial least squares regression (PLSR) and multilayer perceptron (MLP) artificial neural networks (ANNs) trained by back-propagation. The developed models and the corresponding response surface plots were used to select the optimal HPLC conditions, buffer pH 7.0, flow rate 1.0 mL/min, and column temperature 25°C, for an efficient separation of citalopram and its four impurities. The elaborated HPLC method was found to be linear, specific, sensitive, precise, accurate, and robust. Retention times of citalopram and its impurities, obtained with the developed HPLC method, and the computed molecular parameters of the examined compounds were used in a quantitative structure retention relationship (QSRR) study. The PLSR and ANN algorithms were applied for the development of the QSRR methods. The MLP-two layers-ANN-QSRR model with root mean square error of prediction 0.105 and r2 (observed versus predicted) 0.978 was selected. Since many different reaction conditions are applied for the synthesis of citalopram, different impurities and degradation products can be formed. Therefore, the developed QSRR model can be extended to the prediction of the retention times with the other citalopram impurities, degradation products, and metabolites.
Disorder and Everyday Life in Barrancabermeja
Authors: Gill Lesley
Published: June 2012

This article examines how years of political violence and neoliberal restructuring have disorganized social life in Barrancabermeja. How, it asks, can working people grasp the future without the stability to understand the present and the ways that it both emerges and is different from the past? It explores how an extreme form of neoliberalism fragmented various forms of social solidarity, infused social life with fear, and generated violent, clientelistic networks that flourished in the absence of rights. It argues that unrestrained power and violence deprived people of the coherence needed to take care of themselves and to grasp the connections between the past, present, and future that are necessary “to make history.”
El nivel de nacionalización del sistema de partidos colombiano: una mirada a partir de las elecciones legislativas de 2010
Authors: Batlle Margarita , Ricardo Puyana V. José
Published: June 2012

This article deals with the changes and continuities in the levels of nationalization of the Colombian party system, in relation to the literature on the link between political parties, competition, and territory. The article observes the levels of nationalization of political parties: on the one side, those considered traditional, such as the Liberal and Conservative parties, and on the other the new or third parties.
Consideraciones sobre la gobernabilidad como determinante del comportamiento electoral en Colombia: elecciones presidenciales de 2010
Authors: Barrero Fredy A. , Meléndez Carlos
Published: June 2012

This article makes a contribution in the literature on electoral behavior in Colombia. Previous explanations have employed theories that emphasize the explanatory power of income, psico-social considerations and retrospective evaluation in order to assess the impact of programmatic, clientelistic and personalistic party-voter linkages on vote-choice. There is a gap in the literature that we propose to fill through the inclusion of governability appeals as a criterion that electors use when defining their electoral preferences. The fact that certain candidates are perceived with better conditions (or not) to overcome challenges to governability based on their links with powerful veto players is another factor that influences vote choice in addition to key variables (e.g. ideology). Original empirical information, based on the analysis of a national survey data, confirms the hypothesis proposed.
Elecciones parlamentarias de 2010: análisis de la inclusión de mujeres
Authors: Bernal Olarte Angélica
Published: June 2012

The article discusses the results of legislative elections in 2010 in order to assess the political/electoral inclusion of women. It seeks to show how the way of counting votes and allocating seats, the type of constituency and list, affect the degree of incorporation of women in Congress. Addition, it outlines some hypotheses about how certain dynamics within political parties influence the inclusion of women. Besides, proposes to elaborate some hypotheses about the political success of women and their political careers in Congress. The central thesis of the text is that an explanation for the low presence of women in Congress cannot be upheld in the isolated analysis of either of these factors, but requires a complex look that allows seeing the degree of influence of each factor in the political presence of women at this level.
Cuba y Bolivia: dos procesos distintos, ¿una sola revolución verdadera?
Authors: Salazar Boris
Published: June 2012

This article claims that the Bolivian revolutionary process of 2000-2005 did not follow on the steps of the Cuban Revolution’s strategy. The sheer strength and autonomy of its social mobilization, the absence of a maximum leader, and the meshing of democratic elections with mass mobilization have given a turn of the screw on revolutionary strategy in Latin America, producing stable majorities through a lock-in process, whose ultimate outcome has not been the assault on state power. The emergence of a dictator and a unique party in Cuba, and their absence in Bolivia, are explained by the size of their autonomous sociabilities: very large in Bolivia, and very weak in Cuba.
Embodied learning and patient education: From nurses' self‐awareness to patient self‐caring
Authors: Swartz Ann L.
Published: June 2012

This article looks to embodied cognition and embodied cognitive science to explore education for self‐care.
Nanoscale Insight Into Lead‐Free BNT‐BT‐xKNN
Authors: Dittmer Robert , Jo Wook , Rödel Jürgen , Kalinin Sergei , Balke Nina
Published: June 2012

Piezoresponse force microscopy (PFM) is used to afford insight into the nanoscale electromechanical behavior of lead‐free piezoceramics. Materials based on Bi1/2Na1/2TiO3 exhibit high strains mediated by a field‐induced phase transition. Using the band excitation technique the initial domain morphology, the poling behavior, the switching behavior, and the time‐dependent phase stability in the pseudo‐ternary system (1–x)(0.94Bi1/2Na1/2TiO3‐0.06BaTiO3)‐xK0.5Na0.5NbO3 (0 <= x <= 18 mol%) are revealed. In the base material (x = 0 mol%), macroscopic domains and ferroelectric switching can be induced from the initial relaxor state with sufficiently high electric field, yielding large macroscopic remanent strain and polarization. The addition of KNN increases the threshold field required to induce long range order and decreases the stability thereof. For x = 3 mol% the field‐induced domains relax completely, which is also reflected in zero macroscopic remanence. Eventually, no long range order can be induced for x >= 3 mol%. This PFM study provides a novel perspective on the interplay between macroscopic and nanoscopic material properties in bulk lead‐free piezoceramics.
Transfer Printing of Cell Layers with an Anisotropic Extracellular Matrix Assembly using Cell‐Interactive and Thermosensitive Hydrogels
Authors: Jun Indong , Kim Seok Joo , Lee Ji‐Hye , Lee Young Jun , Shin Young Min , Choi Eunpyo , Park Kyung Min , Park Jungyul , Park Ki Dong , Shin Heungsoo
Published: June 2012

The structure of tissue plays a critical role in its function and therefore a great deal of attention has been focused on engineering native tissue‐like constructs for tissue engineering applications. Transfer printing of cell layers is a new technology that allows controlled transfer of cell layers cultured on smart substrates with defined shape and size onto tissue‐specific defect sites. Here, the temperature‐responsive swelling‐deswelling of the hydrogels with groove patterns and their versatile and simple use as a template to harvest cell layers with anisotropic extracellular matrix assembly is reported. The hydrogels with a cell‐interactive peptide and anisotropic groove patterns are obtained via enzymatic polymerization. The results show that the cell layer with patterns can be easily transferred to new substrates by lowering the temperature. In addition, multiple cell layers are stacked on the new substrate in a hierarchical manner and the cell layer is easily transplanted onto a subcutaneous region. These results indicate that the evaluated hydrogel can be used as a novel substrate for transfer printing of artificial tissue constructs with controlled structural integrity, which may hold potential to engineer tissue that can closely mimic native tissue architecture.
Initial Growth Mode, Nanostructure, and Molecular Stacking of a ZnPc:C60 Bulk Heterojunction
Authors: Kim Hyo Jung , Kim Ji Whan , Lee Hyun Hwi , Lee Byeongdu , Kim Jang‐Joo
Published: June 2012

The initial growth modes of ZnPc films is examined, revealing the previously undescribed nanoscale crystal structure evolution and the nanograins of the ZnPc:C60 mixed layers in the thin films. Initially, the ZnPc molecules are stacked in the preferred γ(200) configuration, similar to the structures of CuPc. The ZnPc thin film growth display 2D planar to 3D island growth after the initial compressive strain had relaxed in films 7–8 MLs thick. 3D island formation decreases the prevalence of the preferred ordering in the γ(200) crystals. The ZnPc films consist of randomly distributed ellipsoid nanograins during the initial growth stages. The ellipsoid nanograins transition to an ordered state later in the growth process. Insertion of C60 changes the preferred molecular stacking of ZnPc, and β(100) forms in the ZnPc:C60 layers fabricated at room temperature, which is usually observed at high annealing temperatures (200 °C) in a single ZnPc film. The ellipsoid ZnPc nanograins also retain their shapes in the ZnPc:C60 mixed layers. The formation of β(100) and the presence of ellipsoid nanograins in the mixed layer are related to improvements relative to planar devices in the organic photovoltaic device performance.
Neuropathologic substrates of Parkinson disease dementia
Authors: Irwin David J. , White Matthew T. , Toledo Jon B. , Xie Sharon X. , Robinson John L. , Van Deerlin Vivianna , Lee Virginia M.‐Y. , Leverenz James B. , Montine Thomas J. , Duda John E. , Hurtig Howard I. , Trojanowski John Q.
Published: June 2012

Objective:

A study was undertaken to examine the neuropathological substrates of cognitive dysfunction and dementia in Parkinson disease (PD).

Methods:

One hundred forty patients with a clinical diagnosis of PD and either normal cognition or onset of dementia 2 or more years after motor symptoms (PDD) were studied. Patients with a clinical diagnosis of dementia with Lewy bodies were excluded. Autopsy records of genetic data and semiquantitative scores for the burden of neurofibrillary tangles, senile plaques, Lewy bodies (LBs), and Lewy neurites (LNs) and other pathologies were used to develop a multivariate logistic regression model to determine the independent association of these variables with dementia. Correlates of comorbid Alzheimer disease (AD) were also examined.

Results:

Niney‐two PD patients developed dementia, and 48 remained cognitively normal. Severity of cortical LB (CLB)/LN pathology was positively associated with dementia (p < 0.001), with an odds ratio (OR) of 4.06 (95% confidence interval [CI], 1.87–8.81), as was apolipoprotein E4 (APOE4) genotype (p = 0.018; OR, 4.19; 95% CI, 1.28–13.75). A total of 28.6% of all PD cases had sufficient pathology for comorbid AD, of whom 89.5% were demented. The neuropathological diagnosis of PDD+AD correlated with an older age of PD onset (p = 0.001; OR, 1.12; 95% CI, 1.04–1.21), higher CLB/LN burden (p = 0.037; OR, 2.48; 95% CI, 1.06–5.82), and cerebral amyloid angiopathy severity (p = 0.032; OR, 4.16; 95% CI, 1.13–15.30).

Interpretation:

CLB/LN pathology is the most significant correlate of dementia in PD. Additionally, APOE4 genotype may independently influence the risk of dementia in PD. AD pathology was abundant in a subset of patients, and may modify the clinical phenotype. Thus, therapies that target α‐synuclein, tau, or amyloid β could potentially improve cognitive performance in PD. ANN NEUROL 2012;72:587–598
The matrix protein CCN1/CYR61 is required for αVβ5‐mediated cancer cell migration
Authors: Jandova Jana , Beyer Tracey E. , Meuillet Emmanuelle J. , Watts George S.
Published: June 2012

CYR61 is one of the six proteins of the CCN family of proteins known to play diverse roles in angiogenesis, cellular proliferation, survival, migration and wound healing. However, the specific function of CYR61 in cancer is unclear, and the literature remains controversial. We used quantitative real‐time PCR to establish the expression profile of CYR61 and integrin αVβ5 in three non–small cell lung cancer, five colorectal cancer, one breast cancer and one oesophageal squamous carcinoma cell lines. We showed that the levels of CYR61 were significantly increased in oesophageal squamous carcinoma cell line along with the enhanced levels of αVβ5 integrin. Further, we investigated whether tumour cell–secreted CYR61 can facilitate cell migration by interacting with the αVβ5 integrin. Using tumour cell lines with low, intermediate and high CYR61 expression and their isogenic variants as a cellular model, we determined that integrin αVβ5 expressed on these tumour cells is required for cell migration. Moreover, we showed that the modulation of expression levels of CYR61 in these cancer cells affected their capacity for migration. These results represent an advance to the understanding of the role of CYR61 and αvβ5 integrin as proteins that cooperate to mediate cancer cell migration. Copyright © 2012 John Wiley & Sons, Ltd.
Asymmetric Synthesis of Pochonin E and F, Revision of Their Proposed Structure, and Their Conversion to Potent Hsp90 Inhibitors
Authors: Karthikeyan Ganesan , Zambaldo Claudio , Barluenga Sofia , Zoete Vincent , Karplus Martin , Winssinger Nicolas
Published: June 2012

A concise and modular synthesis of pochonin E and F, and their epimers at C‐6 established the correct stereochemistry of these two natural products. Several members of the pochonin family have been shown to bind the heat shock protein 90 (Hsp90), which has been the focus of intense drug discovery efforts. Pochonin E and F as well as their epimers were derivatized into the corresponding pochoximes and further modified at the C‐6 position. Molecular dynamics simulations, docking studies, and Hsp90 affinity measurements were performed to evaluate the impact of these modifications.
Testing for intercept‐scale switch in linear autoregression
Authors: Ketterer Florian , Holzmann Hajo
Published: June 2012

Autoregressive models with switching regime are a frequently used class of nonlinear time series models, which are popular in finance, engineering, and other fields. We consider linear switching autoregressions in which the intercept and variance possibly switch simultaneously, while the autoregressive parameters are structural and hence the same in all states, and we propose quasi‐likelihood‐based tests for a regime switch in this class of models. Our motivation is from financial time series, where one expects states with high volatility and low mean together with states with low volatility and higher mean. We investigate the performance of our tests in a simulation study, and give an application to a series of IBM monthly stock returns. The Canadian Journal of Statistics 40: 427–446; 2012 © 2012 Statistical Society of Canada
Kinetics and Reaction Engineering of Levulinic Acid Production from Aqueous Glucose Solutions
Authors: Weingarten Ronen , Cho Joungmo , Xing Rong , Conner William Curtis , Huber George W.
Published: June 2012

We have developed a kinetic model for aqueous‐phase production of levulinic acid from glucose using a homogeneous acid catalyst. The proposed model shows a good fit with experimental data collected in this study in a batch reactor. The model was also fitted to steady‐state data obtained in a plug flow reactor (PFR) and a continuously stirred tank reactor (CSTR). The kinetic model consists of four key steps: (1) glucose dehydration to form 5‐hydroxymethylfurfural (HMF); (2) glucose reversion/degradation reactions to produce humins (highly polymerized insoluble carbonaceous species); (3) HMF rehydration to form levulinic acid and formic acid; and (4) HMF degradation to form humins. We use our model to predict the optimal reactor design and operating conditions for HMF and levulinic acid production in a continuous reactor system. Higher temperatures (180–200 °C) and shorter reaction times (less than 1 min) are essential to maximize the HMF content. In contrast, relatively low temperatures (140–160 °C) and longer residence times (above 100 min) are essential for maximum levulinic acid yield. We estimate that a maximum HMF carbon yield of 14 % can be obtained in a PFR at 200 °C and a reaction time of 10 s. Levulinic acid can be produced at 57 % carbon yield (68 % of the theoretical yield) in a PFR at 149 °C and a residence time of 500 min. A system of two consecutive PFR reactors shows a higher performance than a PFR and CSTR combination. However, compared to a single PFR, there is no distinct advantage to implement a system of two consecutive reactors.
Yeast‐Based Microporous Carbon Materials for Carbon Dioxide Capture
Authors: Shen Wenzhong , He Yue , Zhang Shouchun , Li Junfen , Fan Weibin
Published: June 2012

A hierarchical microporous carbon material with a Brunauer–Emmett–Teller surface area of 1348 m2 g−1 and a pore volume of 0.67 cm3 g−1 was prepared from yeast through chemical activation with potassium hydroxide. This type of material contains large numbers of nitrogen‐containing groups (nitrogen content >5.3 wt %), and, consequently, basic sites. As a result, this material shows a faster adsorption rate and a higher adsorption capacity of CO2 than the material obtained by directly carbonizing yeast under the same conditions. The difference is more pronounced in the presence of N2 or H2O, showing that chemical activation of discarded yeast with potassium hydroxide could afford high‐performance microporous carbon materials for the capture of CO2.
A European phylogeography of Rhinanthus minor compared to Rhinanthus angustifolius: unexpected splits and signs of hybridization
Authors: Vrancken Jérôme , Brochmann Christian , Wesselingh Renate A.
Published: June 2012

Rhinanthus minor and Rhinanthus angustifolius (Orobanchaceae) are annual hemiparasites, which occur sympatrically in Europe and are known to hybridize. We studied chloroplast and nuclear (amplified fragment length polymorphism [AFLP]) diversity in R. minor and compared genetic structuring in this species with R. angustifolius by analyzing the AFLP data for both species simultaneously. The AFLP data revealed that populations in Italy, Greece, and southeast Russia initially identified as R. minor were so distant from the other R. minor populations that they probably belong to another, yet unidentified taxon, and we refer to them as Rhinanthus sp. R. minor s.s. showed a clear geographic genetic structure in both the chloroplast DNA (cpDNA) and nuclear genome. The simultaneous analysis of both species shed new light on the previously published findings for R. angustifolius, because some populations now turned out to belong to R. minor. The admixture analysis revealed very few individuals of mixed R. minor–R.angustifolius ancestry in the natural populations in the west of Europe, while admixture levels were higher in the east. The combined haplotype network showed that haplotype H1 was shared among all species and is likely to be ancestral. H2 was more abundant in R. angustifolius and H3 in R. minor, and the latter probably arose from H1 in this species in the east of Europe. The occurrence of H3 in R. angustifolius may be explained by introgression from R. minor, but without interspecific admixture, these are likely to have been old hybridization events. Our study underlines the importance of including related species in phylogeographic studies.
Long‐term breeding phenology shift in royal penguins
Authors: Hindell Mark A. , Bradshaw Corey J. A. , Brook Barry W. , Fordham Damien A. , Kerry Knowles , Hull Cindy , McMahon Clive R.
Published: June 2012

The Earth's climate is undergoing rapid warming, unprecedented in recent times, which is driving shifts in the distribution and phenology of many plants and animals. Quantifying changes in breeding phenology is important for understanding how populations respond to these changes. While data on shifts in phenology are common for Northern Hemisphere species (especially birds), there is a dearth of evidence from the Southern Hemisphere, and even fewer data available from the marine environment. Surface air temperatures at Macquarie Island have increased by 0.62°C during the 30‐year study period (0.21°C decade−1) and royal penguins (Eudyptes schlegeli) commenced egg laying on average three days earlier in the 1990s than during the 1960s. This contrasts with other studies of Southern Ocean seabirds; five of nine species are now breeding on average 2.1 days later than during the 1950s. Despite the different direction of these trends, they can be explained by a single underlying mechanism: resource availability. There was a negative relationship between the Southern Annular Mode (SAM) and median laying date of royal penguins, such that low‐productivity (low SAM) years delayed laying date. This accords with the observations of other seabird species from the Antarctic, where later laying dates were associated with lower sea ice and lower spring productivity. The unifying factor underpinning phenological trends in eastern Antarctica is therefore resource availability; as food becomes scarcer, birds breed later. These changes are not uniform across the region, however, with resource increases in the subantarctic and decreases in eastern Antarctica.
P‐OR Functional Phosphanido and/or Li/OR Phosphinidenoid Complexes?
Authors: Duan Lili , Schnakenburg Gregor , Daniels Jörg , Streubel Rainer
Published: June 2012

P‐H,P‐OR‐substituted phosphane complexes 3a–e have been synthesized by two methods: (1) the thermal reaction of 2H‐azaphosphirene complex 1 with methanol, n‐butanol, or ethylene glycol monomethyl ether (3b,c,e) or (2) the reaction of P‐chlorophosphane complex 2 with appropriate sodium phenolate salts (3a,d). All the complexes 3a–e were obtained in good yields and fully characterized by NMR, IR, MS, and elemental analysis. Furthermore, the structures of 3a, 3d and 3e were confirmed unambiguously by X‐ray analysis. The deprotonation of complexes 3a–e by using lithium diisopropylamide in the presence of 12‐crown‐4 led to phosphinidenoid complexes 4a–e, which exhibit downfield 31P resonances and small tungsten–phosphorus coupling constants. Studies on the reactivity of complexes 4a–c,e revealed a “phosphanido‐type” reactivity, and only for complex 4d, a thermally labile complex, was evidence found for a “phosphinidene‐type” reactivity.
Total Synthesis of Potent Antitumor Macrolide (–)‐Zampanolide: An Oxidative Intramolecular Cyclization‐Based Strategy
Authors: Ghosh Arun K. , Cheng Xu , Bai Ruoli , Hamel Ernest
Published: June 2012

A detailed account of the enantioselective total synthesis of (–)‐zampanolide, a macrolide marine natural product with high anticancer activity, is described. For the synthesis of the 4‐methylenetetrahydropyran unit of (–)‐zampanolide, we initially relied upon an oxidative C–H activation of an alkenyl ether and intramolecular cyclization to provide the substituted tetrahydropyran ring. However, this strategy was unsuccessful. Subsequently, we found that a cinnamyl ether is critical for the successful oxidative intramolecular cyclization reaction. The synthesis also features a cross‐metathesis reaction for the construction of a trisubstituted olefin, a ring‐closing metathesis to form a highly functionalized macrolactone, and a chiral phosphoric acid promoted formation of an N‐acyl aminal to furnish (–)‐zampanolide stereoselectively and in good yield. The synthetic (–)‐zampanolide had effects on cultured cells and on tubulin assembly consistent with the properties reported for the natural product.
Monte Carlo simulations on the thermodynamic properties of high‐density gases
Authors: Hu Shide
Published: June 2012

The thermodynamic properties of Ar, H2 and CH4 at high‐density conditions are studied using Monte Carlo simulations. The isotherms of Ar at 500K, H2 at 1000K and CH4 at 500K are obtained respectively. To validate the accuracy of the simulation results, the thermodynamic properties of these gases are also studied with van der Waals equation and compared with the reference data. The agreement with reference shows that Monte Carlo method can produce reliable thermodynamic properties of high‐density gases based on the accurate intermolecular potential model. Therefore, the accuracy of the simulations depends primarily on the accuracy of the potential model, and this dependence is also discussed. Copyright © 2012 John Wiley & Sons, Ltd.
Preliminary country‐scale assessment of carbon dioxide storage potential in Iran
Authors: Movagharnejad Kamyar , Emamgholivand Azadeh , Mousavi Hamed , Kordkheili Masoud Sheikhi
Published: June 2012

This study is a country‐scale assessment of the CO2 storage potential in Iran. Estimates are given of the CO2 storage capacity in saline water‐bearing sedimentary rocks and enhanced oil and gas recovery operations. The results suggest that of the order of 70 Gt CO2 storage capacity may be present in saline aquifers, approximately 19 Gt CO2 storage capacity could result from enhanced oil recovery, and 1.1 Gt capacity could result from enhanced gas recovery, indicating great potential for CO2 storage in Iran. These results must be treated with great caution however, due to the scoping nature of the study. More detailed studies of the most promising basins are recommended. Enhanced oil recovery appears to be the most promising route to geological CO2 storage in Iran because of the potential economic benefits. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd
Spatiotemporal distribution of cortical processing of first and second languages in bilinguals. I. Effects of proficiency and linguistic setting
Authors: Pratt Hillel , Abbasi Dalal Abu‐Amneh , Bleich Naomi , Mittelman Nomi , Starr Arnold
Published: June 2012

The study determined how spatiotemporal distribution of cortical activity to words in first and second language is affected by language, proficiency, and linguistic setting. Ten early bilinguals and 14 late adult bilinguals listened to pairs of words presented in Arabic (L1), Hebrew (L2), or in mixed pairs and indicated whether both words had the same meaning or not. Source current densities of event‐related potentials were estimated. Activity to first words in the pair lateralized to right hemisphere, higher to L1 than L2 during early processing (<300 ms) among both groups but only among late bilinguals during late processing (>300 ms). During early and late processing, activities were larger in mixed than monolinguistic settings among early bilinguals but lower in mixed than in monolinguistic settings among late bilinguals. Late processing in auditory regions was of larger magnitude in left than right hemispheres among both groups. Activity to second words in the pair was larger in mixed than in monolinguistic settings during both early and late processing among both groups. Early processing of second words in auditory regions lateralized to the right among early bilinguals and to the left among late bilinguals, whereas late processing did not differ between groups. Wernicke's area activity during late processing of L2 was larger on the right, while on the left no significant differences between languages were found. The results show that cortical language processing in bilinguals differs between early and late processing and these differences are modulated by linguistic proficiency and setting. Hum Brain Mapp 34:2863–2881, 2013. © 2012 Wiley Periodicals, Inc.
Lab on a chip technologies for algae detection: a review
Authors: Schaap Allison , Rohrlack Thomas , Bellouard Yves
Published: June 2012

Over the last few decades, lab on a chip technologies have emerged as powerful tools for high‐accuracy diagnosis with minute quantities of liquid and as tools for exploring cell properties in general. In this paper, we present a review of the current status of this technology in the context of algae detection and monitoring. We start with an overview of the detection methods currently used for algae monitoring, followed by a review of lab on a chip devices for algae detection and classification, and then discuss a case study based on our own research activities. We conclude with a discussion on future challenges and motivations for algae‐oriented lab on a chip technologies. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Estradiol protects adipose tissue–derived stem cells against H2O2‐induced toxicity
Authors: Taskiran Dilek , Evren Vedat
Published: June 2012

Oxidative stress is associated with various pathophysiological processes, including cell survival, adhesion, apoptosis, and cancer. In the present study, we aimed to evaluate the effects of H2O2‐induced toxicity on adipose tissue–derived stem cells (ADSCs) and whether 17β‐estradiol (E2) has protective effects on these cells. ADSCs derived from adult Sprague–Dawley rats were pretreated with different doses of E2 for 24 h and then exposed to 200 µM H2O2 for 4 h. Incubation of ADSCs with H2O2‐decreased cell viability in a concentration‐dependent fashion (p < 0.0001), whereas pretreatment of these cells with E2 significantly reversed toxicity (p < 0.05), inhibited apoptotic changes, and decreased lipid peroxidation (p < 0.0005). Our findings suggest that E2 protects ADSCs from oxidative‐induced cell death, and therefore, it may be used to improve the survival rate and regenerative capacity of stem cells. © 2012 Wiley Periodicals, Inc. J Biochem Mol Toxicol 26:301–307, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.21421
On orthogonality constrained multiple core‐hole states and optimized effective potential method
Authors: Glushkov V. N. , Assfeld X.
Published: June 2012

An attempt to construct a multiple core‐hole state within the optimized effective potential (OEP) methodology is presented. In contrast to the conventional Δ‐self‐consistent field method for hole states, the effects of removing an electron is achieved using some orthogonality constraints imposed on the orbitals so that a Slater determinant describing a hole state is constrained to be orthogonal to that of a neutral system. It is shown that single, double, and multiple core‐hole states can be treated within a unified framework and can be easily implemented for atoms and molecules. For this purpose, a constrained OEP method proposed earlier for excited states (Glushkov and Levy, J. Chem. Phys. 2007, 126, 174106) is further developed to calculate single and double core ionization energies using a local effective potential expressed as a direct mapping of the external potential. The corresponding equations, determining core‐hole orbitals from a one‐particle Schrödinger equation with a local potential as well as correlation corrections derived from the second‐order many‐body perturbation theory are given. One of the advantages of the present direct mapping formulation is that the effective potential, which plays the role of the Kohn–Sham potential, has the symmetry of the external potential. Single and double core ionization potentials computed with the presented scheme were found to be in agreement with data available from experiment and other calculations. We also discuss core‐hole state local potentials for the systems studied. © 2012 Wiley Periodicals, Inc.
Diffusion‐tensor MRI reveals the complex muscle architecture of the human forearm
Authors: Froeling Martijn , Nederveen Aart J. , Heijtel Dennis F.R. , Lataster Arno , Bos Clemens , Nicolay Klaas , Maas Mario , Drost Maarten R. , Strijkers Gustav J.
Published: June 2012

Purpose:

To design a time‐efficient patient‐friendly clinical diffusion tensor MRI protocol and postprocessing tool to study the complex muscle architecture of the human forearm.

Materials and Methods:

The 15‐minute examination was done using a 3 T system and consisted of: T1‐weighted imaging, dual echo gradient echo imaging, single‐shot spin‐echo echo‐planar imaging (EPI) diffusion tensor MRI. Postprocessing comprised of signal‐to‐noise improvement by a Rician noise suppression algorithm, image registration to correct for motion and eddy currents, and correction of susceptibility‐induced deformations using magnetic field inhomogeneity maps. Per muscle one to five regions of interest were used for fiber tractography seeding. To validate our approach, the reconstructions of individual muscles from the in vivo scans were compared to photographs of those dissected from a human cadaver forearm.

Results:

Postprocessing proved essential to allow muscle segmentation based on combined T1‐weighted and diffusion tensor data. The protocol can be applied more generally to study human muscle architecture in other parts of the body.

Conclusion:

The proposed protocol was able to visualize the muscle architecture of the human forearm in great detail and showed excellent agreement with the dissected cadaver muscles. J. Magn. Reson. Imaging 2012. © 2012 Wiley Periodicals, Inc.
Shifting imaging targets in multiple sclerosis: From inflammation to neurodegeneration
Authors: Vigeveno René M. , Wiebenga Oliver T. , Wattjes Mike P. , Geurts Jeroen J.G. , Barkhof Frederik
Published: June 2012

Classically multiple sclerosis (MS) has been regarded as an auto‐immune disease of the white matter in the central nervous system leading to severe disability over the course of several decades. Current therapeutic strategies in MS are mostly based on either immune suppression or immune modulation. Although effective in decreasing relapse frequency and severity as well as delaying disease progression, MS pathology ensues nonetheless. In the last decade it became evident that gray matter pathology plays an important role in disease progression and helps explaining certain aspects of MS‐related disability such as cognitive decline. Conventional MRI outcome measures commonly used in clinical trials are sufficient to demonstrate an anti‐inflammatory drug‐effect but lack pathological specificity and are poor to moderate predictors of disability. In this article, we review new insights in gray matter pathology and functional reorganization in MS and how these novel fields in MS research may validate and establish new MRI outcome measures, aid in the development of new therapeutic strategies for neuroprotection and neurorepair, and may lead to development of novel predictive measures of disability and disease progression in MS. J. Magn. Reson. Imaging 2012; 36:1–19. © 2012 Wiley Periodicals, Inc.