bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploratory Factor Analysis and Structural Equation Modeling
Authors: Ockey Gary J.
Published: November 2013

This chapter discusses exploratory factor analysis (EFA) and structural equation modeling (SEM) techniques, two quantitative analytic methods commonly used in the field of language assessment. EFA is a data‐driven approach which is generally used as an investigative technique to identify relationships among variables. SEM is an a priori theory approach which is most often used to determine the extent to which an already established theory about relationships among variables is supported by empirical data. The chapter provides guidelines for using each of the techniques. Conducting an EFA requires screening and preparing the data for analysis, extracting eigenvalues, determining the number of factors for a solution, rotating the factors to a more interpretable solution, and providing an interpretation for the solution. Conducting an SEM analysis requires identifying the model, collecting and screening data appropriate for the analyses, estimating the parameters of the model, assessing the fit of the model to the data, interpreting the model's parameters, and evaluating the plausibility of competing models.

To illustrate the principles and concepts of EFA, a self‐assessment of academic abilities data set is analyzed. A four‐factor model is found to be the most defensible factor structure. A second self‐assessment of academic abilities data set is then analyzed with an SEM approach with the aim of confirming or disconfirming the four‐factor structure identified with the EFA approach. Discussion and justification for decisions made during each step in the two analyses, along with an interpretation of the results, are provided. Common uses of EFA and SEM in language testing along with a brief historical overview of these techniques are also included in the chapter. The chapter concludes with a call for researchers to follow appropriate guidelines and principles when using one or the other of the techniques.
AssessingKorean
Authors: Kim Chungsook , Lee Junho
Published: November 2013

The purpose of this chapter is to introduce the assessment tools and the systems, which evaluate a test taker's Korean language ability, and to diagnose the present state of assessments. The chapter introduces Korean assessment for both native speakers and non‐native speaker,s focusing on evaluation methods, assessment tools, and evaluation categories.

As the Republic of Korea's official language, the number of Korean speakers has steadily increased and currently 770 million people around the world use it. By population, Korean is in the top 13 languages in the world. With such an increase in the number of Korean speakers and international status, the importance of Korean proficiency assessments is increasing and demand for assessment is also increasing internally and externally. In addition, the results of the Korean proficiency test are being used as a major qualification for admission or employment of Korean native speakers as well as non‐native speakers, so the social impact of the assessment of Korean proficiency is growing. In this chapter, current Korean language proficiency assessment is studied analytically to describe a more positive development direction. In particular, the Korean section of the College Scholastic Aptitude Test, the major academic skills assessment tool for native speakers, and the Test of Proficiency in Korean, for non‐native speakers, are intensively analyzed.
Assessing Heritage Language Learners
Authors: Llosa Lorena
Published: November 2013

In the last few decades, research on how to best teach and assess heritage language (HL) learners has grown as enrollment of these students in language classes has increased. Recent work on the assessment of HL learners has been conducted in the context of higher education in the USA and has focused almost exclusively on placement testing. This chapter first reviews the various characterizations and characteristics of the heritage language population. The next section discusses approaches to placement testing of HL learners and reviews specific studies that have been conducted related to these different approaches. The approaches include the use of self‐placements and demographic questionnaires, standardized foreign language exams, and locally developed placement tests. Finally, the chapter concludes by discussing challenges in the placement testing of HL learners and future directions for research.
Assessing
Malayalam
Authors: Sadanandan Suchitra
Published: November 2013

This chapter examines the assessment of Malayalam in schools and in the workplace. It begins with a brief description of the language, highlighting areas like orthography and dialectal variations that are pertinent to the assessment practices examined. This is followed by a description of language education in schools in the state of Kerala in India (where the language is mainly spoken). The Malayalam language component in two examination systems in schools—the Secondary School Leaving Certificate exam administered by the Kerala Curriculum Board and the exam administered by the Central Board of Secondary Education—are taken up for an in‐depth analysis. Similarly the Malayalam language component of two examinations in the workplace—the LDC exam that is necessary for employment in the Kerala Public Service Commission and the Indian Administrative Services exam—are also examined. Analyses of these examinations show that they include both skills‐based and memory‐based assessments. A striking omission in all of them is the absence of listening and speaking assessments. The chapter concludes with a call for research on the validity, reliability, and fairness of the assessments and an appeal for reports of these research studies to be made available to the public.
Language Testing for Immigration to Europe
Authors: Van Avermaet Piet , Pulinx Reinhilde
Published: November 2013

Since the beginning of the 21st century, integration and citizenship discourses and policies have become more and more intertwined in contemporary superdiverse societies in Western Europe. Flanders (Belgium) is a clear example of how integration is gradually being replaced by virtual or moral citizenship. The concept of citizenship is used in multiple ways: citizenship as nationality, but also citizenship as a set of norms and values (which immigrants particularly have to comply with) and citizenship as identification with the host society. The authors argue that the “integration policy” in Flanders is in fact a hidden “citizenship policy” that includes the old, obsolete, and static concepts and definitions of monolingualism, nationality, and ethnicity. In these renewed integration policies, proficiency in the dominant language and knowledge of the host society are seen as conditions for social participation, therefore new immigrants have to take a compulsory integration course and “older” migrants are made to enroll in Dutch language courses. Increasingly, standardized tests—and especially language tests—are used to determine the learning outcomes of these courses and to regulate possibilities of social and economic participation. The authors advocate looking at citizenship and the use of plurilingual repertoires in the city as dynamic and contextualized processes, shaped in daily practice through negotiation in social networks. In a context where “superdiversity” is becoming the norm, it is important to reflect on the boundaries of the current recipes—integration policies including obligatory language tests—that are being used to promote and strengthen social and civic activity.
Language Testing in the Dock
Authors: Fulcher Glenn
Published: November 2013

The practice of language testing for purposes other than second language learning research is primarily concerned with making decisions about education and employment. The purpose of the test is to generate a score, the meaning of which is both relevant to, and useful for, the decision to be taken. Individuals who obtain sufficiently high scores gain access to educational programs or jobs, or obtain certification that allows mobility to other institutions or countries; those who do not achieve these cut scores are denied the same benefits. Large‐scale testing is therefore a social tool for rationing limited resources and opportunities.

It is therefore inevitable that some individuals or groups will challenge either the meaning or the use of the test scores. This is most likely to happen if they feel that the test outcomes are “unfair” because they perceive their score as unrepresentative of their true ability. They are most likely to succeed if they can successfully argue that they have been discriminated against. Discrimination occurs where the test score is construct irrelevant or under‐representative, and significantly varies according to some protected factor, such as ethnicity or disability. It is also possible to challenge the relevance of the score to the decision context, particularly if the score is not predictive of likely future performance.

This chapter sets out the conditions under which legal challenges may be brought against test providers or users on the basis of discrimination or test misuse, and argues that litigation in language testing is likely to grow as the market value of test scores increases.
Mixed Methods Research
Authors: Turner Carolyn E.
Published: November 2013

Since the early 1990s, mixed methods research (MMR) has evolved into the third research paradigm alongside quantitatively oriented inquiry (numeric data) and qualitatively oriented inquiry (narrative data). MMR is interested in both quantitative and qualitative analyses and primarily works from a pragmatic stance to use what works best in order to answer research questions. The research question, rather than a preconceived paradigm (e.g., post‐positivist, positivist, constructivist), is central and drives the choice of design. The interest in and practice of MMR have emerged rapidly and spread across many domains in the social and behavioral sciences. Within this context, the focus of this chapter is on discussing MMR as it has manifested itself within the language testing/assessment (LT) research community. In some ways MMR's evolution in LT parallels its general emergence, but in other ways there are developments specific to the LT field. For example, MMR is increasingly being employed for instrument development, classroom‐based assessment, and large‐scale assessment studies. In addition, MMR designs are being used to address issues such as construct definition and rater effects in language assessments. To help explain this evolution, the chapter situates MMR from an historical perspective and discusses how LT research designs are increasingly situating themselves in this third research community. As this trajectory is traced in LT research, the chapter also describes the nature, conventions, practice, and research designs that are emerging and becoming specific to the LT field. It is interesting, however, that any debate or discussion of MMR issues seems less prevalent in LT, whereas it is abundant in the general MMR literature. What is important to note is that LT's rationale for the use of MMR follows closely the philosophical orientation most often associated with it, that is, pragmatism.
The Role of the Face and Body in Unfamiliar Person Identification
Authors: Rice Allyson , Phillips P. Jonathon , O'Toole Alice
Published: November 2013

Information useful for identifying a person can be found both in the face and body. Previous studies indicate that when an entire person is visible, we rely strongly on the face for identification, even if the body can be useful. We measured the utility of the face versus body for identification, by using images of unfamiliar people that varied in the quality of identity information in the face. Face quality was varied using similarity scores generated by state‐of‐the‐art face recognition algorithms from an international competition. These algorithms estimated the similarity of faces in a large set (>1 000 000) of image pairs that showed ‘people’, including the face and the top half of the body. By using these similarity scores, image pairs were stratified into three groups representing good, moderate, and poor performance for the face recognition algorithm. Participants matched identity in image pairs sampled from the three groups, by using versions of the stimuli edited digitally to show only the face or body. Consistent with the algorithm stratifications, performance with the face declined across the three conditions. The face supported more accurate identification than the body in the good and moderate conditions. In the poor condition, performance from the face and body was comparable. Using data from a previous study, we compared the face‐only and body‐only identity judgments with judgments based on the original image. The original unedited image supported the best overall performance in the good and moderate conditions. Notably, performance in the poor condition was equivalent for the face, body, and original images. The results indicate that in poor viewing conditions, identification decisions from the body may be as accurate as those made from the face or the entire person. Copyright © 2013 John Wiley & Sons, Ltd.
Active fault tolerant control of piecewise affine systems with reference tracking and input constraints
Authors: Gholami M. , Cocquempot V. , Schiøler H. , Bak T.
Published: November 2013

An active fault tolerant control (AFTC) method is proposed for discrete‐time piecewise affine (PWA) systems. Only actuator faults are considered. The AFTC framework contains a supervisory scheme, which selects a suitable controller in a set of controllers such that the stability and an acceptable performance of the faulty system are held. The design of the supervisory scheme is not considered here. The set of controllers is composed of a normal controller for the fault‐free case, an active fault detection and isolation controller for isolation and identification of the faults, and a set of passive fault tolerant controllers (PFTCs) modules designed to be robust against a set of actuator faults. In this research, the piecewise nonlinear model is approximated by a PWA system. The PFTCs are state feedback laws. Each one is robust against a fixed set of actuator faults and is able to track the reference signal while the control inputs are bounded. The PFTC problem is transformed into a feasibility problem of a set of LMIs. The method is applied on a large‐scale live‐stock ventilation model. Copyright © 2013 John Wiley & Sons, Ltd.
A reduced MIMO Wiener model for recursive identification of the depth of anesthesia
Authors: Silva Margarida M. , Wigren Torbjörn , Mendonça Teresa
Published: November 2013

This paper presents a modeling and identification strategy for the depth of anesthesia using the propofol and remifentanil rates as the system inputs, and the bispectral index and state entropy measurements as the systems outputs. The standard model used for this purpose has twenty two patient‐dependent parameters. This high number of parameters, the little input excitation, and the small amount of output data make classical system identification approaches unsuccessful. To overcome these issues, the new model presented in this paper has six parameters, thereby meeting the parsimony principle of system identification. An extended Kalman filter algorithm is also developed and applied to real data. The good fitting results, combined with noise suppression and a recursive update of the model parameters, are promising for the design of the depth of anesthesia controllers to be used in real time platforms. Copyright © 2013 John Wiley & Sons, Ltd.
Highly Porous Magnesium Alloy Structures and Their Properties Regarding Degradable Implant Application
Authors: Morgenthal Ingrid , Andersen Olaf , Kostmann Cris , Stephani Günter , Studnitzky Thomas , Witte Frank , Kieback Bernd
Published: November 2013

Magnesium alloys offer excellent properties with regard to application as degradable implant. For bone implants, it is often desirable to use porous materials. However, the preparation of high‐porosity magnesium implants has been difficult so far. The present study uses melt extracted magnesium fibers as the starting material for the sintering of highly porous magnesium bodies, i.e., from alloys MgY4 (W4) and MgY2Zn1CaMn (WZ21). Single short fibers of these alloys with an equivalent diameter between 100 and 250 µm and a length of 4–8 mm are manufactured by melt extraction. Thermodynamic calculations are used to determine the best conditions for liquid phase sintering of these Mg alloys. As no organic or other substances are needed in the process, it is possible to obtain high‐purity, high‐porosity (up to 75%) bodies with exclusively open porosity. Metallographic studies as well as mechanical and corrosion testing experiments complete this work.
Convenient and Reliable Routes Towards 2‐Aminothiazoles: Palladium‐Catalyzed versus Copper‐Catalyzed Aminations of Halothiazoles
Authors: Toulot Stéphanie , Heinrich Timo , Leroux Frédéric R.
Published: November 2013

Two efficient methods for the amination of 2‐halothiazoles are presented here. A first protocol requires a Pd/L system. Several 2‐aminothiazoles were synthesized under optimized conditions and isolated in good yields. The first palladium‐catalyzed CN coupling reactions between 2‐halothiazoles and primary alkylamines are presented. In a second part, ligand‐free copper‐catalyzed aminations of 2‐halothiazoles by alkylamines and aniline in a green solvent have been developed. The protocol is very effective for primary and secondary amines and perfectly tolerates the presence of another halide moiety on the 2‐halothiazole. The reaction occurs under the assistance of microwave irradiation, which drastically decreases the reaction time. The reaction leads to the formation of 2‐aminothiazoles, key molecules in pharmaceutical research.

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Palladium(0)‐Catalyzed Regioselective Synthesis of Macrocycles from Allenes with a Nucleophilic Functionality and Organic Iodides
Authors: Huang Xin , Jiang Xinpeng , Fu Chunling , Ma Shengming
Published: November 2013

A highly regioselective synthesis of 15–20‐membered macrocycles via Pd(0)‐catalyzed coupling cyclization of allenes bearing a carbon or nitrogen nucleophilic functionality and organic iodides is reported. After oxidative addition and carbopalladation, anti‐π‐allyl palladium intermediates were formed, which was followed by the exclusive intramolecular nucleophilic attack at the terminal carbon atom of the allene moiety to afford products with yields ranging from 44–92% and E/Z ratios of up to 97/3.

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Generation of 4‐Cyanoisoquinolines and 4‐Amidylisoquinolines via a Palladium‐Catalyzed Cyanative Reaction of 2‐Alkynylbenzaldimines with Isocyanides
Authors: Qiu Guanyinsheng , Qiu Xiaochen , Wu Jie
Published: November 2013

An efficient route to 4‐cyanoquinolines via a palladium‐catalyzed cyanative reaction of 2‐alkynylbenzaldimines with isocyanides has been developed. The transformation proceeds through 6‐endo cyclization, isocyanide insertion, and cyanation. 4‐Amidylisoquinolines can be generated as well if water is involved in the reaction.

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Sulfoxide‐to‐Sulfilimine Conversions: Use of Modified Burgess‐Type Reagents
Authors: Hendriks Christine M. M. , Lamers Philip , Engel Julien , Bolm Carsten
Published: November 2013

Sulfoxides can directly be converted into N‐cyanosulfilimines using a new Burgess‐type reagent. By applying this strategy with a related reagent variant, synthetically valuable NH‐sulfoximines have been prepared from sulfoxides via N‐protected sulfilimines. The practical three‐step reaction sequence is generally high yielding and applicable to a wide range of substrates. The sulfoxide‐to‐sulfilimine conversion can also be performed under solvent‐reduced conditions in a ball mill.

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Influence of Thermal Annealing on PCDTBT:PCBM Composition Profiles
Authors: Synooka Olesia , Eberhardt Kai‐Rudi , Singh Chetan Raj , Hermann Felix , Ecke Gernot , Ecker Bernhard , von Hauff Elizabeth , Gobsch Gerhard , Hoppe Harald
Published: November 2013

A variety of measurement techniques including photothermal deflection spectroscopy (PDS), auger electron spectroscopy (AES), (sub–bandgap) external quantum efficiency (EQE), and impedance spectroscopy are applied to poly[N‐900‐hepta‐decanyl‐2,7‐carbazole‐alt‐5,5‐(40,70‐di‐2‐thienyl‐20,10,30‐benzothiadiazole (PCDTBT)/[6,6]‐phenyl C71 butyric acid methyl ester (PC71BM) films and devices to probe the stability under thermal annealing. Upon annealing, solar cell performance is drastically decreased for temperatures higher than 140 °C. Detailed investigation indicate changes in polymer:fullerene interactions resulting in the formation of a polymer wetting layer upon annealing at temperatures higher than 140 °C. Upon device completion this wetting layer is located close to the metal electrode and therefore leads to an increase in recombination and a decrease in charge carrier extraction, providing an explanation for the reduced fill factor (FF) and power conversion efficiency (PCE).
Partial dysfunction of Treg activation in sickle cell disease
Authors: Vingert Benoît , Tamagne Marie , Desmarets Maxime , Pakdaman Sadaf , Elayeb Rahma , Habibi Anoosha , Bernaudin Françoise , Galacteros Frédéric , Bierling Philippe , Noizat‐Pirenne France , Cohen José
Published: November 2013

Sickle cell disease (SCD) is a chronic inflammatory disease associated with multiple organ damage, chronic anemia, and infections. SCD patients have a high rate of alloimmunization against red blood cells (RBCs) following transfusion and may develop autoimmune diseases. Studies in mouse models have suggested that regulatory T cells (Treg) play a role in alloimmunization against RBC antigens. We characterized the phenotype and function of the Treg cell population in a homogeneous cohort of transfused SCD patients. We found that the distribution of Treg subpopulations differed significantly between SCD patients and healthy blood donors. SCD patients have a particular Treg phenotype, with strong CTLA‐4 and CD39 expression and weak HLA‐DR and CCR7 expression. Finally, we show that this particular phenotype is related to SCD rather than alloimmunization status. Indeed, we observed no difference in Treg phenotype or function in vitro using autologous feeder cells between strong and weak responders to alloimmunization. Am. J. Hematol. 89:261–266, 2014. © 2013 Wiley Periodicals, Inc.
Role of endogenous IL‐18 in the lung during endotoxin‐induced systemic inflammation
Authors: Takahara Miki , Aoyama‐Ishikawa Michiko , Shuno Katsuhito , Yamauhi Chisato , Miyoshi Makoto , Maeshige Noriaki , Usami Makoto , Yamada Taihei , Osako Takaaki , Nakao Atsunori , Kotani Joji
Published: November 2013

Background

Overactivated neutrophils are causes of acute lung injury, which is a major clinical problem with significant morbidity and mortality in sepsis. Serum interleukin (IL)‐18 levels correspond to severity of systemic inflammation.

Aim

To elucidate the roles of endogenous IL‐18 in lung injury during endotoxin‐induced systemic inflammation.

Methods

Wild‐type (WT) and IL‐18 gene knockout (KO) mice were injected with lipopolysaccharide (40 mg/kg) intraperitoneally and killed. Lungs were collected at 0 and 12 h to assess mRNA for intercellular adhesion molecule (ICAM)‐1, inducible nitric oxide synthase, myeloperoxidase, immunohistochemistry (cleaved caspase‐3, 8‐hydroxy‐2‐deoxyguanosine), and wet/dry ratio. Blood was collected at 0, 1, 12, 18, and 24 h to assess plasma cytokine levels.

Results

The survival rates at 24 h were approximately 43% and 76% in the WT and KO mice, respectively. Plasma IL‐18 levels were induced time‐dependently only in the WT mice. Plasma interferon‐γ levels were significantly higher in the WT than in the KO mice at 12 h, but IL‐6 and tumor necrosis factor‐α levels did not differ between the WT and KO mice. At 12 h, the WT mice showed higher myeloperoxidase activity (P < 0.05), ICAM‐1, and wet/dry ratios than KO mice. Cleaved caspase‐3 positive neutrophils, which migrated in the lung interstitium, were lower in WT mice than in KO mice.

Conclusions

Endogenous IL‐18 induced neutrophil accumulation, accompanied by induction of ICAM‐1 expression, inhibition of neutrophil apoptosis, and increased inducible nitric oxide synthase‐induced oxidative tissue injury in the lung, leading to lung edema and poor outcome during endotoxemia.
Symmetry‐Guided Synthesis of Highly Porous Metal–Organic Frameworks with Fluorite Topology
Authors: Zhang Muwei , Chen Ying‐Pin , Bosch Mathieu , Gentle Thomas , Wang Kecheng , Feng Dawei , Wang Zhiyong U. , Zhou Hong‐Cai
Published: November 2013

Two stable, non‐interpenetrated MOFs, PCN‐521 and PCN‐523, were synthesized by a symmetry‐guided strategy. Augmentation of the 4‐connected nodes in the fluorite structure with a rigid tetrahedral ligand and substitution of the 8‐connected nodes by the Zr/Hf clusters yielded MOFs with large octahedral interstitial cavities. They are the first examples of Zr/Hf MOFs with tetrahedral linkers. PCN‐521 has the largest BET surface area (3411 m2 g‐1), pore size (20.5×20.5×37.4 Å) and void volume (78.5%) of MOFs formed from tetrahedral ligands. This work not only demonstrates a successful implementation of rational design of MOFs with desired topology, but also provides a systematic way of constructing non‐interpenetrated MOFs with high porosity.
Mastication behavior of cis‐1,4‐polyisoprene as a model for natural rubber
Authors: Wortmann Christopher , Lindner Patrick , Dettmer Fabian , Steiner Frank , Scheper Thomas
Published: November 2013

The mastication behavior of synthetic cis‐1,4‐polyisoprene (IR), deproteinized natural rubber (DPNR), and natural rubber (NR) in an internal mixer has been investigated at mixing temperatures from 88 to 186°C and different levels of mechanical energy, using Mooney viscosity and size exclusion chromatography (SEC). An envelope‐shaped mastication efficiency curve and high similarity in the mastication behavior can be observed for IR and NR but not for DPNR. The minimum of the envelope‐shaped curve shifts to lower temperatures when the mechanical energy is increased. Based on these findings, a mathematical description for the contribution of mechanical and thermo‐oxidative mastication mechanisms has been established. Distinct statistical distribution of thermo‐oxidative scission can only be observed in SEC measurements of materials masticated at high temperatures over 170°C. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39989.
Synthesis and Evaluation of Novel 2,3‐Dihydrobenzo[b][1,4]dioxin‐ and Indolealkylamine Derivatives as Potential Antidepressants
Authors: Wang Songlin , Chen Yin , Liu Xinghua , Xu Xiangqing , Liu Xin , Liu Bi‐Feng , Zhang Guisen
Published: November 2013

A series of 2,3‐dihydrobenzo[b][1,4]dioxin‐ and indolealkylamine derivatives were synthesized and the target compounds were evaluated for their binding affinities at the 5‐HT1A receptor and serotonin transporter. Antidepressant‐like activities of the compounds were screened using the tail suspension and forced swim tests in mice. Preliminary results indicated that the target compounds exhibited high binding affinities at the 5‐HT1A receptor and serotonin transporter, and produced marked antidepressant‐like effects. The best example from this study, compound 5, exhibited high binding affinities for the 5‐HT1A receptor (Ki = 96 nM) and serotonin transporter (Ki = 9.8 nM). The intrinsic activity of compound 5 showed agonistic property to the 5‐HT1A receptor and inhibition of the 5‐HT transporter. Furthermore, compound 5 exhibited greater antidepressant efficacy than fluoxetine and showed acceptable pharmacokinetic properties.
Dipyrido[3,2‐a:2′,3′‐c]phenazine‐Based Donor–Acceptor Aromatic Heterocyclic Compounds with Thienyl and Triphenylamino Chromophores at the 2,7‐ and/or 10,13‐Positions
Authors: Wang Xiao‐Xu , Tao Tao , Geng Jiao , Ma Bin‐Bin , Peng Yu‐Xin , Huang Wei
Published: November 2013

A series of T‐ and H‐shaped donor–acceptor (D–A) types of dipyrido[3,2‐a:2′,3′‐c]phenazine (DPPZ)‐based molecules, extended by thienyl and triphenylamino chromophores at the 2,7‐(bottom) and/or 10,13‐positions (top), have been designed and prepared successfully. Synthetic, structural, thermal, spectral, and computational comparisons have been carried out for related compounds because of their adjustable intramolecular charge‐transfer properties. It is noted that a pair of structural isomers (5 and 6) has been obtained, respectively, where distinguishable UV/Vis and fluorescence spectra, electrochemical activity, thermal stability, and bandgaps are observed. Furthermore, compounds 6, 8, 10, 11, 13, and 15 exhibit excellent thermal stability, and the Td10 values for them are found to range from 524 to 646 °C, which can be regarded as one of the best groups of thermally stable compounds among organic small molecules. In addition, theoretical calculations were performed, and the structure–property relationships were examined to reveal the effects of the position and number of donor arms on the DPPZ acceptor core.
Linking physiology to toxicity using DILIsym®, a mechanistic mathematical model of drug‐induced liver injury
Authors: Shoda Lisl K. M. , Woodhead Jeffrey L. , Siler Scott Q. , Watkins Paul B. , Howell Brett A.
Published: November 2013

The drug development industry faces multiple challenges in the realization of safe effective drugs. Computational modeling approaches can be used to support these efforts. One approach, mechanistic modeling, is new to the realm of drug safety. It holds the promise of not only predicting toxicity for novel compounds, but also illuminating the mechanistic underpinnings of toxicity. To increase the scientific community's familiarity with mechanistic modeling in drug safety, this article seeks to provide perspective on the type of data used, how they are used and where they are lacking. Examples are derived from the development of DILIsym® software, a mechanistic model of drug‐induced liver injury (DILI). DILIsym® simulates the mechanistic interactions and events from compound administration through the progression of liver injury and regeneration. Modeling mitochondrial toxicity illustrates the type and use of in vitro data to represent biological interactions, as well as insights on key differences between in vitro and in vivo conditions. Modeling bile acid toxicity illustrates a case in which the over‐arching mechanism is well accepted, but many mechanistic details are lacking. Modeling was used to identify measurements predicted to strongly impact toxicity. Finally, modeling innate immune responses illustrates the importance of time‐series data, particularly in the presence of positive and negative feedback loops, as well as the need for data from different animal species for better translation. These concepts are germane to most mechanistic models, although the details will vary. The use of mechanistic models is expected to improve the rational design of new drugs. Copyright © 2013 John Wiley & Sons, Ltd.
Platinum N‐Heterocyclic Carbene Nanoparticles as New and Effective Catalysts for the Selective Hydrogenation of Nitroaromatics
Authors: Lara Patricia , Suárez Andrés , Collière Vincent , Philippot Karine , Chaudret Bruno
Published: November 2013

In this communication, we report the first synthesis of Pt NPs stabilized with NHC ligands and their investigation as catalysts in the chemoselective hydrogenation of nitroarenes. The results in catalysis show that by a proper choice of the NHC stabilizer and the adjustment of the NHC/metal ratio, these NHC‐capped Pt NPs exhibit high levels of activity and selectivity in the hydrogenation reactions. In particular, Pt NPs stabilized with 2 equiv. of IPr carbene (PtIPr0.2) catalyze the chemoselective reduction of a series of functionalized nitroarenes under mild conditions (1 bar H2, 30 °C). This catalyst tolerates the presence of a range of functional groups including hydroxyl, benzyloxy, carbonyl and olefinic moeities as well as halogens.
Combined Fixed‐Bed Reactor and In Situ DRIFTS Tests of NO Adsorption on a NOx Storage‐Reduction System Catalyst
Authors: Wu Dong L. , Tschamber Valerie , Limousy Lionel , Michelin Laure , Westermann Alexandre , Azambre Bruno , Fechete Ioana , Garin François
Published: November 2013

The effect of water on NOx storage performance of a Pt/BaO/Al2O3 catalyst was investigated. The adsorption capacity of a model NOx storage‐reduction system (NSR) catalyst was studied in the presence of NO, oxygen, and water in nitrogen. Fixed‐bed and in situ DRIFTS adsorption tests were carried out in order to evaluate the influence of water on the adsorption capacity of the catalyst, adsorbed species on the surface of the catalyst, and stability of these species. The presence of water slightly reduces the NOx storage capacity of the NSR catalyst. A decrease of platinum oxidation activity was observed which was correlated to a slowdown of surface bidentate nitrate formation, detected by in situ DRIFTS tests. On the other hand, surface monodentate nitrates were favored and formation of bulk nitrates was not affected. A set of reactions corresponding to these observations is proposed.
Wavelet‐based self‐organizing maps for classifying multivariate time series
Authors: D'Urso Pierpaolo , De Giovanni Livia , Maharaj Elizabeth Ann , Massari Riccardo
Published: November 2013

Following a nonparametric approach, we suggest a time‐series clustering method. Our clustering approach combines the benefits connected to the interpretative power of the nonparametric representation of the time series, and the clustering and vector quantization informational gain produced by the adopted unsupervised neural networks technique, enhanced with the self‐organizing maps ordering and topological preservation abilities. The proposed clustering method takes into account a composite wavelet‐based information of the multivariate time series by adding to the information connected to the wavelet variance, namely the influence of variability of individual univariate components of the multivariate time series across scales, the information associated to wavelet correlation, represented by the interaction between pairs of univariate components of the multivariate time series at each scale, and then suitably tuning the combination of these pieces of information. In order to assess the effectiveness of the proposed clustering approach, a simulation study and an empirical application are shown. Copyright © 2013 John Wiley & Sons, Ltd.
Polycationic Pillar[5]arene Derivatives: Interaction with DNA and Biological Applications
Authors: Nierengarten Iwona , Nothisen Marc , Sigwalt David , Biellmann Thomas , Holler Michel , Remy Jean‐Serge , Nierengarten Jean‐François
Published: November 2013

Dendritic pillar[5]arene derivatives have been efficiently prepared by grafting dendrons with peripheral Boc‐protected amine subunits onto a preconstructed pillar[5]arene scaffold. Upon cleavage of the Boc‐protected groups, water‐soluble pillar[5]arene derivatives with 20 (13) and 40 (14) peripheral ammonium groups have been obtained. The capability of these compounds to form stable nanoparticles with plasmid DNA has been demonstrated by gel electrophoresis, transmission electron microscopy (TEM), and dynamic light scattering (DLS) investigations. Transfection efficiencies of the self‐assembled 13/pCMV‐Luc and 14/pCMV‐Luc polyplexes have been evaluated in vitro with HeLa cells. The transfection efficiencies found for both compounds are good, and pillar[5]arenes 13 and 14 show very low toxicity if any.
The Effect of Humic Acids on Zymogenous Microbial Consortia Growth
Authors: Miletić Srdjan B. , Spasić Snežana D. , Avdalović Jelena , Beškoski Vladimir , Ilić Mila , Gojgić‐Cvijović Gordana , Vrvić Miroslav M.
Published: November 2013

This paper describes experiments with standard humic acids (HA‐S) and humic acids (HA) isolated from soil that was contaminated with mazut and treated with a consortium of microorganisms for the process of bioremediation (HA‐E). Both acids inhibited the toxicity of ferric chloride and increased the growth of a zymogenous microbial consortia compared with controls. Electron paramagnetic resonance spectroscopy showed that HA‐S and HA‐E exhibit high anti‐oxidative activity involving free radical scavenging and iron sequestration. HA additionally promote microbial consortium growth by providing protection from oxidative stress.
Budget and Fate of Phosphorus and Trace Metals in a Heavily Loaded Shallow Reservoir (Shahe, Beijing City)
Authors: Zhang Hong , Pernet‐Coudrier Benoît , Wen Shengfang , Müller Beat , Shan Baoqing
Published: November 2013

Shahe Reservoir in the headwater of the Wenyu River, Beijing City, was selected for a case study evaluating the effects of both urbanization and agricultural intensification on the cycling of phosphorus (P), as well as Cr, Cu, and Ni. This study showed that the construction of the reservoir in 1960 resulted in an increased retention of P, Cr, Cu, and Ni in its sediment. The load of these elements to the river system has sharply increased since the 1980s. For P, the mean sediment content was 890 ± 270 mg/kg before 1980, but thereafter increased to 1540 ± 700 mg/kg. Most of the sedimentary P was apatite P (47%). The average sediment contents of Cu and Ni increased from 37.3 and 28.8 g/kg to 61.6 and 60.7 mg/kg, respectively. According to mass balance calculations, the actual annual input loads were 110 t P, 500 kg Cr, 520 kg Cu, and 600 kg Ni. Whereas the reservoir retained about 50% of the trace metal loads in its sediment, P retention was only 7%. Hence, the sediment contribution to the P balance of the reservoir is almost negligible and sediment manipulation cannot be a measure for the mitigation of eutrophication in this reservoir.
Sublethal Effect of Arsenic on Oxidative Stress and Antioxidant Status in Scylla serrata
Authors: Saha Sanjib , Ray Sajal
Published: November 2013

Estuarine edible crab, Scylla serrata (Crustacea: Decapoda) occupy diverse habitats and their strategy of survival is correlated to multidimensional immune responses and its inhabiting in bio‐unsafe environment is under constant threat of physiological stress caused by diverse xenobiotics including arsenic. Experimental crabs, exposed to 1–3 ppm of sodium arsenite for a maximum period of 30 days in controlled laboratory condition indicated that arsenic as cytotoxicant as well as immunotoxicant causes damage and an alteration in cytotoxic status and antioxidant status in hemocytes. In this study, we investigated the intrahemocytic production of phenoloxidase, super oxide anion, nitric oxide, and its subsequent scavenging under the exposure of sodium arsenite. Arsenic induced variations in generation of cytotoxic molecules as well as antioxidant enzymes activity in intrahemocyte is indicative to possible immune‐alteration of the animal distributed in bio‐unsafe environment. Arsenic induced impairment of immune response may initiate an opportunistic growth of microbes in crab. Chronic exposure of S. serrata to arsenic may lead to decline of this economically important endemic species in Sundarbans Biosphere Reserve of West Bengal.
Effects of pH Manipulation, Biological Reduction, and Plant Growth on Cu2+ and Zn2+ Removal from Mine Drainage Using Iron‐Oxide‐Enriched Red Earth Soils
Authors: Zhang Youchi , Hu Chaohua , Luo Wensui
Published: November 2013

Constructed wetland is an efficient method used to control heavy metal pollution from acidic wastewater, especially when local soils could be used as filling material to reduce construction cost. This study investigated the effects of pH manipulation, biological reduction, and plant growth on the removal of heavy metals (Cu2+ and Zn2+) using iron‐oxide‐enriched red earth soils. Results indicated that red earth soils had limited metal retention capacity (MRC), whereas CaCO3 alteration significantly improved MRC. In the batch experiment, MRCs of Cu2+ and Zn2+ in 3% CaCO3 alteration were 420 and 291 mg/kg, respectively, compared with values of 246 and 117 mg/kg without alteration. In column studies, the effluent concentrations of Cu2+ and Zn2+ remained <0.03 and 0.13 mg/L, respectively, compared with over 0.96 and 10.81 mg/L without alteration. Biological reduction caused iron‐oxide mineral dissolution, but heavy metals remained within the soils. The growth of Canna (Canna indica) prompted Cu2+ transport deep into soil layers. However, the metal transport was retarded by CaCO3 alteration. In, conclusion, red earth soils with CaCO3 alteration could be cost‐effective filling materials to attenuate heavy metal pollution from mining drainage using constructed wetland even under biological reduction and plant growth conditions.
Adsorption of Copper and Zinc on Activated Carbon Prepared from Typha latifolia L.
Authors: Song Jinfeng , Zhang Riqing , Li Kelin , Li Bing , Tang Chunfang
Published: November 2013

The physicochemical characteristic of activated carbon, prepared from Typha latifolia L. by phosphoric acid, was analyzed by spectroscopic analysis. Batch sorption of Cu2+ and Zn2+ ions in aqueous solutions was investigated under different pH value, adsorption time, original content of metal ions, sorbent amount, and temperature. Results showed that adsorption capacity of Cu2+ and Zn2+ increased with the increase of pH value of solution. It needed only about 10 min to reach equilibrium adsorption and pseudo second‐order sorption model was used to depict the adsorption process. The thermodynamics studies suggested that the adsorption process was spontaneous and endothermic. Equilibrium adsorption data of both metal ions fitted reasonably well with the Langmuir and Freundlich isotherms. The maximum adsorption capacity of Cu2+ and Zn2+ obtained from the Langmuir adsorption isotherm studies was found to be 34.48 and 28.57 mg g−1, respectively, at pH 6 and temperature of 25°C. Wastewater treatment showed that cattail‐based activated carbon prepared by phosphoric acid activation is a promising material for the treatment of metal ions out of industrial wastewater.
Synthesis, Characterization, and Antimicrobial Activity of Silver(I) and Copper(II) Complexes of Phosphate Derivatives of Pyridine And Benzimidazole
Authors: Kalinowska‐Lis Urszula , Szewczyk Eligia M. , Chęcińska Lilianna , Wojciechowski Jakub M. , Wolf Wojciech M. , Ochocki Justyn
Published: November 2013

Two silver(I) complexes—{[Ag(4‐pmOpe)]NO3}n and [Ag(2‐bimOpe)2]NO3—and three copper(II) complexes—[Cu4Cl6O(2‐bimOpe)4], [CuCl2(4‐pmOpe)2], and [CuCl2(2‐bis(pm)Ope]—were synthesized by reaction of silver(I) nitrate or copper(II) chloride with phosphate derivatives of pyridine and benzimidazole, namely diethyl (pyridin‐4‐ylmethyl)phosphate (4‐pmOpe), 1H‐benzimidazol‐2‐ylmethyl diethyl phosphate (2‐bimOpe), and ethyl bis(pyridin‐2‐ylmethyl)phosphate (2‐bis(pm)Ope). These compounds were characterized by 1H, 13C, and 31P NMR as well as IR spectroscopy, elemental analysis, and ESIMS spectrometry. Additionally, molecular and crystal structures of {[Ag(4‐pmOpe)]NO3}n and [Cu4Cl6O(2‐bimOpe)4] were determined by single‐crystal X‐ray diffraction analysis. The antimicrobial profiles of synthesized complexes and free ligands against test organisms from the ATCC and clinical sources were determined. Silver(I) complexes showed good antimicrobial activities against Candida albicans strains (MIC values of ∼19 μM). [Ag(2‐bimOpe)2]NO3 was particularly active against Pseudomonas aeruginosa and methicillin‐resistant Staphylococcus epidermidis, with MIC values of ∼5 and ∼10 μM, respectively. Neither copper(II) complexes nor the free ligands inhibited the growth of test organisms at concentrations below 500 μg mL−1.
Supporting multidimensional range queries in Hierarchically Distributed Tree
Authors: Gu Yunfeng , Boukerche Azzedine , De Grande Robson E.
Published: November 2013

An examination of the multidimensional range query in existing peer‐to‐peer (P2P) overlay networks indicates that multidimensional range queries are sensitive to underlying topologies; this is because partitioning and mapping of multidimensional data space are two interconnected parts of a process that must be carried out cooperatively. The first section focuses on how to preserve data localities, whereas the second section concerns how to accommodate and maintain data localities at the P2P overlay layer. There are many studies that have been conducted on the first section since 1966, and those works that are well accepted are mostly based on recursive decomposition, which forms a tree structure in nature. However, less effort has been made to provide comparable support from the P2P overlay layer. In our previous work, we proposed the Hierarchically Distributed Tree (HD Tree) in order to better support multidimensional range queries in the P2P overlay network. This paper further explores error‐resilient routing and load balancing strategies that can be employed in the HD Tree. We also provide a complete set of experimental results for all routing operations: Join and Leave of nodes, range queries at different levels of selectivity, and the dynamic load balancing scheme. Comparisons are made by conducting simulations under both the ideal and the error‐prone routing environment and within various ary HD Trees. The experimental results show that load balancing in the HD Tree can be adjusted dynamically and globally, and it is actually a trade‐off between distributing the basic load and the involvement of nodes in range querying. The experimental results also indicate that a maximum of 10 percent of routing nodes’ failures do not have significant effects on the performance of range queries. However, a lower ary HD Tree appears to have better routing performance, whereas a higher ary HD Tree achieves a higher fault‐tolerant capacity. Nevertheless, the performance of range queries in a higher ary HD Tree can be further optimized if all possible routing options can be fully explored in the error‐prone routing environment. Copyright © 2013 John Wiley & Sons, Ltd.
Selective Production of Methane from Aqueous Biocarbohydrate Streams over a Mixture of Platinum and Ruthenium Catalysts
Authors: Neira D'Angelo Maria Fernanda , Ordomsky Vitaly , van der Schaaf John , Schouten Jaap C. , Nijhuis Tjeerd Alexander
Published: November 2013

A one‐step process for the selective production of methane from low‐value aqueous carbohydrate streams is proposed. Sorbitol, used herein as a model compound, is fully converted to methane, CO2, and a minor amount of H2 by using a physical mixture of Pt and Ru (1:5 in mass basis) at 220 °C and 35 bar. This conversion is the result of hydrogenolysis of part of the sorbitol over Ru and the in situ production of H2 through the aqueous‐phase reforming of the remaining carbohydrate over Pt. A synergistic effect of the combination of these two catalysts results in the rapid and highly selective conversion of the carbohydrate to methane. This process offers the possibility of upgrading a low‐value carbohydrate stream into a valuable fuel with no addition of H2. Exergy analysis reveals that nearly 80 % of the exergy of the reactant is recovered as methane.