bluuebunny/crossref_metadata_2025 huggingface dataset:
A statistical approach to modelling permafrost distribution in the European Alps or similar mountain ranges
Authors: Boeckli L. , Brenning A. , Gruber S. , Noetzli J.
Published: January 2012

Abstract. Estimates of permafrost distribution in mountain regions are important for the assessment of climate change effects on natural and human systems. In order to make permafrost analyses and the establishment of guidelines for e.g. construction or hazard assessment comparable and compatible between regions, one consistent and traceable model for the entire Alpine domain is required. For the calibration of statistical models, the scarcity of suitable and reliable information about the presence or absence of permafrost makes the use of large areas attractive due to the larger data base available. We present a strategy and method for modelling permafrost distribution of entire mountain regions and provide the results of statistical analyses and model calibration for the European Alps. Starting from an integrated model framework, two statistical sub-models are developed, one for debris-covered areas (debris model) and one for steep bedrock (rock model). They are calibrated using rock glacier inventories and rock surface temperatures. To support the later generalization to surface characteristics other than those available for calibration, so-called offset terms have been introduced into the model that allow doing this in a transparent and traceable manner. For the debris model a generalized linear mixed-effect model (GLMM) is used to predict the probability of a rock glacier being intact as opposed to relict. It is based on the explanatory variables mean annual air temperature (MAAT), potential incoming solar radiation (PISR) and the mean annual sum of precipitation (PRECIP), and achieves an excellent discrimination (area under the receiver-operating characteristic, AUROC = 0.91). Surprisingly, the probability of a rock glacier being intact is positively associated with increasing PRECIP for given MAAT and PISR conditions. The rock model is based on a linear regression and was calibrated with mean annual rock surface temperatures (MARST). The explanatory variables are MAAT and PISR. The linear regression achieves a root mean square error (RMSE) of 1.6 °C. The final model combines the two sub-models and accounts for the different scales used for model calibration. The modelling approach provides a theoretical basis for estimating mountain permafrost distribution over larger mountain ranges and can be expanded to more surface types and sub-models than considered, here. The analyses performed with the Alpine data set further provide quantitative insight into larger-area patterns as well as the model coefficients for a later spatial application. The transfer into a map-based product, however, requires further steps such as the definition of offset terms that usually contain a degree of subjectivity.
Interpersonal Rejection Sensitivity and Regulatory Focus Theory to Explain College Students' Class Engagement
Authors: Roscheck David , Schweinle William E.
Published: January 2012

The current study investigated the relationship between undergraduate students' sensitivity to rejection and their level of participation in positive classroom engagement. One hundred and thirty-five undergraduate students from an upper-Midwest university volunteered to participate in a survey as part of their Psychology 101 course. As hypothesized, there was a negative correlation between students' sensitivity to rejection and their level of participation in positive class behaviors. We also found that this relationship was moderated by the regulatory focus, “prevention pride”. The greater a student's prevention pride was, the more likely the student was to have an average amount of participation in positive class behaviors, regardless of their sensitivity to rejection. These findings suggest that students who do not become engaged in positive classroom behaviors may be afraid to do so for fear of rejection by peers and/or instructors, and that this relationship is moderated to a large degree by the students' prevention pride.
International Education Studies: Increasing Their Linguistic Comparability by Developing Judgmental Reviews
Authors: Arffman Inga
Published: January 2012

In international education studies, the different-language test versions need to be equally difficult to read and answer for the test to be valid. To ensure comparability, several quality control procedures have been developed. Among these, surprisingly little attention has been paid to judgmental reviews and their ability to identify language-related sources of bias. Also, the reviews have often failed in identifying biases. This paper explored whether it is possible to improve the ability of judgmental reviews to identify language-related sources of bias. A new review was made of two Finnish items which in the PISA (Programme for International Student Assessment) 2000 reading test showed differential item functioning but for which no clear language-related explanations were found in the review in 2000. The items were compared systematically, at all linguistic levels, to the corresponding items in the English and French source versions, at the same time taking into account the cognitive processes required to answer them and students’ written responses to them. Language-related explanations were found for both items which may have led to differences in performance, suggesting that it is possible to make judgmental reviews better able to identify language-related bias. Suggestions are given on how to do this.
Possible Impact of the Fourth-Generation Quarks on Production of a Charged Higgs Boson at the LHC
Authors: Çiftçi R. , Çiftçi A. K. , Sultansoy S.
Published: January 2012

We investigate the impact of the fourth-generation quarks on production and decays of the charged Higgs boson at CERN Large Hadron Collider (LHC) with 14 TeV center of mass energy. The signal is the process gg→u4¯u4, followed by u4¯→W−b¯ and u4→h+b decays with subsequent h+→tb̅ and corresponding hermitic conjugates. It is shown that if mu4=400 GeV, then considered process will provide unique opportunity to discover charged Higgs boson with mass range of 200 to 350 GeV at the LHC.
The Association between Alcohol Dependence and Depression before and after Treatment for Alcohol Dependence
Authors: Kuria Mary W. , Ndetei David M. , Obot Isodore S. , Khasakhala Lincoln I. , Bagaka Betty M. , Mbugua Margaret N. , Kamau Judy
Published: January 2012

The presence of depression in alcohol-dependent persons is likely to influence treatment process and outcomes. Identification of depression is important though not every depressed alcohol-dependent person requires treatment with antidepressants. Understanding the association between depression and alcohol dependence is essential for proper management of alcohol dependence. Objectives. To determine the prevalence of depression among alcohol-dependent persons before and after alcohol detoxification and rehabilitation. Design. Clinical trial with pre-/postmeasurements. Method. The CIDI and WHO-ASSIST were administered to 188 alcohol-dependent persons at intake and after six months. A researcher-designed sociodemographic questionnaire was also administered at intake. Results. The prevalence of depression among alcohol-dependent persons is high (63.8%) with a significant association between depression and the mean AUDIT score. At posttest, depressed participants had a statistically significant craving for alcohol. Conclusion. Alcohol dependence is associated with major depression.
HIV and AIDS Programmes in Zimbabwe: Implications for the Health System
Authors: Chevo Tafadzwa , Bhatasara Sandra
Published: January 2012

This paper analyzes the implications of HIV and AIDS prevention, treatment, and care programmes on the health system in Zimbabwe. The programmes have been spearheaded by various stakeholders that include the public and private sectors, nongovernmental organizations, formal and informal institutions, and intergovernmental organizations. There has been a tremendous increase of the programmes as they adapt to local contexts, accommodate new funders, and changes in population attitudes, and expectations in the country. Through a comprehensive literature review, this paper focuses on Behaviour Change, the Antiretroviral Therapy, Home-Based Care, Prevention to Mother To Child Transmission and Voluntary Counselling and Testing programmes and services in relation to the components of the health system that include health service delivery, human resources, finance, leadership and governance, and the medical products and technologies. Thus far, the implications are uneven throughout the health system and there is need to integrate the HIV and AIDS programmes within the health system in order to achieve positive heath outcomes.
Development and Stability Studies of Novel Liposomal Vancomycin Formulations
Authors: Muppidi Krishna , Pumerantz Andrew S. , Wang Jeffrey , Betageri Guru
Published: January 2012

A promising strategy to improve the therapeutic efficiency of antimicrobial agents is targeted therapy. Although vancomycin has been considered a gold standard for the therapy of MRSA pneumonia, clinical failure rates have also been reported owing to its slow, time-dependent bactericidal activity, variable lung tissue penetration and poor intracellular penetration into macrophages. Liposomal encapsulation has been established as an alternative for antimicrobial delivery to infected tissue macrophages and offers enhanced pharmacodynamics, pharmacokinetics and decreased toxicity compared to standard preparations. The aim of the present work is to prepare vancomycin in two different liposomal formulations, conventional and PEGylated liposomes using different methods. The prepared formulations were optimized for their particle size, encapsulation efficiency and physical stability. The dehydration-rehydration was found to be the best preparation method. Both the conventional and PEGylated liposomal formulations were successfully formulated with a narrow particle size and size distribution and % encapsulation efficiency of and , respectively. Both the formulations were stable at C for 3 months. These formulations were successfully used to evaluate for their intracellular killing of MRSA and in vivo pharmacokinetic and bio-distribution studies.
Decreased Vitamin B12Levels in Children with Nocturnal Enuresis
Authors: Altunoluk Bülent , Davutoglu Mehmet , Garipardic Mesut , Bakan Vedat
Published: January 2012

Objectives. Nocturnal enuresis is a common pediatric problem, the etiology of which is unclear. In the present study, vitamin B12and folate levels were measured in children with nocturnal enuresis and compared with those in healthy control group children to investigate whether there was any relation with enuresis and neurogenic maturation as a first time in the literature.Methods. In this cross-sectional study, we included thirty children (16 girls, 14 boys) who had presented with primary nocturnal enuresis (PNE) complaints in the study group and 31 children (13 girls, 18 boys) in the control group. Body weight and height measurements were obtained and complete blood counts and vitamin B12and folate levels were measured in all children.Results. No difference was found in age, height, and weight between study and control groups. Also the mean levels of the hemoglobin, hematocrit, and mean corpuscular volume (MCV) were not different between the two groups. Significantly lower mean vitamin B12and folate levels were found in the enuresis group compared with the control group.Conclusions. Further studies are needed to clarify B12and folate deficiency in larger series so that these tests can be included in routine investigations of enuretic children.
Maximize Post‐Treatment to Stabilize Desalinated Water
Authors: Duranceau Steven
Published: January 2012

A growing number of water utilities turning to desalination emphasize the importance of understanding the behavior of desalted permeate within a distribution system and the potential problems if proper post‐treatment processes aren't practiced.
Energy Audits Pour Out Savings
Authors: Reguly Ted
Published: January 2012

This article discusses how a comprehensive pilot program in California is shifting the energy‐efficiency focus from consumers to water agencies.
Improving Slow Sand Filters for Water‐Limited Communities
Authors: Erazo‐Oliveras Angélica , May Ol‐Bracero Olga L. , Ríos‐Dávila Rafael A.
Published: January 2012

Slow sand filtration offers a natural alternative for obtaining potable water. A recent project in Puerto Rico explored ways to improve construction of slow sand filters and develop a simple, low‐cost sand‐cleaning method that didn't require large quantities of water.
Mentors Pay It Forward
Authors: Copeland Ari
Published: January 2012

Being a good supervisor and mentor will help your employees enhance their job skills and enrich your own career. Here are some tips for those who are or will be mentoring or supervising others.
Create a Water Tank Sustainability Plan
Authors: Henderson Erika
Published: January 2012

When creating a sustainability plan for a potable water tank, consider the type of tank, its location, and maintenance requirements.
A New Approach to Model‐Based Simulation of Disordered Polymer Blend Solar Cells
Authors: Stenzel Ole , Koster L. Jan Anton , Thiedmann Ralf , Oosterhout Stefan D. , Janssen René A. J. , Schmidt Volker
Published: January 2012

The 3D nanomorphology of blends of two different (organic and inorganic) solid phases as used in bulk heterojunction solar cells is described by a spatial stochastic model. The model is fitted to 3D image data describing the photoactive layer of poly(3‐hexylthiophene)‐ZnO (P3HT‐ZnO) solar cells fabricated with varying spin‐coating velocities. A scenario analysis is performed where 3D morphologies are simulated for different spin‐coating velocities to elucidate the correlation between processing conditions, morphology, and efficiency of hybrid P3HT‐ZnO solar cells. The simulated morphologies are analyzed quantitatively in terms of structural and physical characteristics. It is found that there is a tendency for the morphology to coarsen with increasing spin‐coating velocity, creating larger domains of P3HT and ZnO. The impact of the spin‐coating velocity on the connectivity of the morphology and the existence of percolation pathways for charge carriers in the resulting films appears insignificant, but the quality of percolation pathways, considering the charge carrier mobility, strongly varies with the spin‐coating velocity, especially in the ZnO phase. Also, the exciton quenching efficiency decreases significantly for films deposited at large spin‐coating velocities. The stochastic simulation model investigated is compared to a simulated annealing model and is found to provide a better fit to the experimental data.
Robust Hollow Spheres Consisting of Alternating Titania Nanosheets and Graphene Nanosheets with High Photocatalytic Activity for CO2 Conversion into Renewable Fuels
Authors: Tu Wenguang , Zhou Yong , Liu Qi , Tian Zhongping , Gao Jun , Chen Xiaoyu , Zhang Haitao , Liu Jianguo , Zou Zhigang
Published: January 2012

Robust hollow spheres consisting of molecular‐scale alternating titania (Ti0.91O2) nanosheets and graphene (G) nanosheets are successfully fabricated by a layer‐by‐layer assembly technique with polymer beads as sacrificial templates using a microwave irradiation technique to simultaneously remove the template and reduce graphene oxide into graphene. The molecular scale, 2D contact of Ti0.91O2 nanosheets and G nanosheets in the hollow spheres is distinctly different from the prevenient G‐based TiO2 nanocomposites prepared by simple integration of TiO2 and G nanosheets. The nine times increase of the photocatalytic activity of G‐Ti0.91O2 hollow spheres relative to commercial P25 TiO2 is confirmed with photoreduction of CO2 into renewable fuels (CO and CH4). The large enhancement in the photocatalytic activity benefits from: 1) the ultrathin nature of Ti0.91O2 nanosheets allowing charge carriers to move rapidly onto the surface to participate in the photoreduction reaction; 2) the sufficiently compact stacking of ultrathin Ti0.91O2 nanosheets with G nanosheets allowing the photogenerated electron to transfer fast from the Ti0.91O2 nanosheets to G to enhance lifetime of the charge carriers; and 3) the hollow structure potentially acting as a photon trap‐well to allow the multiscattering of incident light for the enhancement of light absorption.
Atomic Layer Deposition of Nanostructured Materials for Energy and Environmental Applications
Authors: Marichy Catherine , Bechelany Mikhael , Pinna Nicola
Published: January 2012

Atomic layer deposition (ALD) is a thin film technology that in the past two decades rapidly developed from a niche technology to an established method. It proved to be a key technology for the surface modification and the fabrication of complex nanostructured materials. In this Progress Report, after a short introduction to ALD and its chemistry, the versatility of the technique for the fabrication of novel functional materials will be discussed. Selected examples, focused on its use for the engineering of nanostructures targeting applications in energy conversion and storage, and on environmental issues, will be discussed. Finally, the challenges that ALD is now facing in terms of materials fabrication and processing will be also tackled.
Spray‐Assisted Polyelectrolyte Multilayer Buildup: from Step‐by‐Step to Single‐Step Polyelectrolyte Film Constructions
Authors: Schaaf Pierre , Voegel Jean‐Claude , Jierry Loïc , Boulmedais Fouzia
Published: January 2012

The alternate deposition of polyanions and polycations on a solid substrate leads to the formation of nanometer to micrometer films called Polyelectrolyte Multilayers. This step‐by‐step construction of organic films constitutes a method of choice to functionalize surfaces with applications ranging from optical to bioactive coatings. The method was originally developed by dipping the substrate in the different polyelectrolyte solutions. Recent advances show that spraying the polyelectrolyte solutions onto the substrate represents an appealing alternative to dipping because it is much faster and easier to adapt at an industrial level. Multilayer deposition by spraying is thus greatly gaining in interest. Here we review the current literature on this deposition method. After a brief history of polyelectrolyte multilayers to place the spraying method in its context, we review the fundamental issues that have been addresses so far. We then give an overview the different fields where the method has been applied.
Optimization of Electrodeposited p‐Doped Sb2Te3 Thermoelectric Films by Millisecond Potentiostatic Pulses
Authors: Schumacher Christian , Reinsberg Klaus G. , Akinsinde Lewis , Zastrow Sebastian , Heiderich Sonja , Toellner William , Rampelberg Geert , Detavernier Christophe , Broekaert José A. C. , Nielsch Kornelius , Bachmann Julien
Published: January 2012

A systematic optimization of p‐type Sb2Te3 thermoelectric films made by potentiostatic electrodeposition on Au and stainless steel substrates is presented. The influence of the preparative parameters of deposition voltage, concentration, and the deposition method are investigated in a nitric acid solution. As a postdeposition step, the influence of annealing the films is investigated. The use of a potential‐controlled millisecond‐pulsed deposition method could improve both the morphology and the composition of the films. The samples are characterized in terms of composition, crystallinity, Seebeck coefficient, and electrical resistivity. Pulsed‐deposited films exhibit Seebeck coefficients of up to 160 μV K−1 and an electrical conductivity of 280 S cm−1 at room temperature, resulting in power factors of about 700 μW m−1 K−2. After annealing, power factors of maximum 852 μW m−1 K−2 are achieved. Although the annealing of DC‐deposited films significantly increased the power factor, they do not reach the values of the pulsed‐deposited films in the preannealing state. Structural analysis is performed with X‐ray diffraction and shows the crystalline structure of Sb2Te3 films. The performance is tuned by annealing of deposited films up to 300 °C under He atmosphere while performing in‐situ X‐ray diffraction and resistivity measurements. The chemical analysis of the films is performed by inductively coupled plasma optical emission spectroscopy (ICP‐OES) as well as scanning electron microscope energy dispersive X‐ray analysis (SEM‐EDX).
Exact results with the Kotliar‐Ruckenstein slave‐boson representation
Authors: Frésard R. , Kopp T.
Published: January 2012

Radial slave boson representations have the particular advantage that the expectation values of their respective fields are finite even without the formal introduction of spurious Bose condensates for each of the bosonic fields. The expectation values of the radial (real) fields are in fact to be interpreted as the density of empty or singly occupied sites. Whereas the radial representation of the Barnes slave bosons has been investigated before, a setup for the functional integral of radial bosonic fields in the more physical Kotliar‐Ruckenstein representation has not been accomplished to date. We implement a path integral procedure with suitable renormalization factors for a strongly correlated two‐site model which allows to control the formal steps in the intricate evaluation, as the results for the partition function and the expectation values are known from exact diagonalization for such a minimal single impurity Anderson model. The partition function is shown to be a trace over a product of matrices local in time and therefore can be calculated analytically. Eventually, we establish the scheme for the evaluation of correlation functions and thermodynamic properties.
Impurity diffusion, point defect engineering, and surface/interface passivation in germanium
Authors: Chroneos A. , Schwingenschlögl U. , Dimoulas A.
Published: January 2012

In recent years germanium has been emerging as a mainstream material that could have important applications in the microelectronics industry. The principle aim of this study is to review investigations of the diffusion of technologically important p‐ and n‐type dopants as well as surface and interface passivation issues in germanium. The diffusion of impurities in germanium is interrelated to the formation of clusters whenever possible, and possibilities for point defect engineering are discussed in view of recent results. The importance of electrically active defects on the Ge surface and interfaces is addressed considering strategies to suppress them and to passivate the surfaces/interfaces, bearing in mind their importance for advanced devices.
Organophosphine/phosphite‐stabilized silver(I) complexes bearing N‐hydroxysuccinimide ligand: synthesis, solid state structure and their potential use as MOCVD precursors
Authors: Tao Xian , Shen Ke‐Cheng , Tang Qing‐Yun , Feng Meng , Fang Jiang‐Tao , Wang Yu‐Long , Shen Ying‐Zhong
Published: January 2012

Six organophosphine/phosphite‐stabilized silver(I) N‐hydroxysuccinimide complexes of type [C4H4NO3Ag⋅Ln] (L = PPh3; n = 1, 2a; n = 2, 2b; L = P(OEt)3; n = 1, 2c; n = 2, 2 d; L = P(OMe)3; n = 1, 2e; n = 2, 2f) were prepared. These complexes were obtained in high yields and characterized by elemental analysis, 1H NMR, 13 C{1H} NMR and IR spectroscopy, respectively. The molecular structure of 2b has been determined by X‐ray single‐crystal analysis in which the silver atom is in a distorted tetrahedral geometry. An interstitial methanol solvent molecule is hydrogen bonded to the oxygen atom of N‐hydroxysuccinimide molecule. Complex 2f was used to deposit silver films by metal‐organic chemical vapor deposition (MOCVD) for the first time. The silver film obtained at 480 °C is dense and homogeneous, which is composed of many well‐isolated, granular particulates spreading all over the substrate surface. Copyright © 2012 John Wiley & Sons, Ltd.
Polylactide latex/nanofibrillated cellulose bionanocomposites of high nanofibrillated cellulose content and nanopaper network structure prepared by a papermaking route
Authors: Larsson Karolina , Berglund Lars A. , Ankerfors Mikael , Lindström Tom
Published: January 2012

Previous attempts to use polylactide (PLA) latex particles and nanofibrillated cellulose (NFC) in papermaking processing have been limited to low NFC content. In the present study, a bionanocomposite material was successfully produced using a PLA latex and NFC. The components were mixed using a wet mixing method and bionanocomposite films were made by filtration followed by hot pressing. In composite materials, the dispersion of the reinforcing component in the matrix is critical for the material properties. Biopolymers such as PLA are non‐polar and soluble only in organic solvents; NFC is, however, highly hydrophilic. By utilizing latex, i.e., an aqueous dispersion of biopolymer micro‐particles, wet mixing is possible and the problem of aggregation of the hydrophilic nanocellulose in organic solvent is avoided. The properties of the resulting NFC/PLA latex bionanocomposite films were analyzed. Thorough blending resulted in good dispersion of the reinforcing component within the matrix. Adding increasing amounts of NFC improved the Young's modulus, tensile strength, and strain at break of the bionanocomposite material. The increase in the tensile properties was linear with increasing NFC content as a result of the good dispersion. The NFC also improved the thermal stability of the bionanocomposite material. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Alcohol‐induced change of “reverse osmosis” polyamide membrane surface
Authors: Agrawal Vinod K. , Singh Puyam S.
Published: January 2012

An analysis method based on Attenuated total reflectance infra‐red spectroscopy was used to measure water and alcohol sorption from water–methanol and water–isopropanol aqueous solutions in the “reverse osmosis” polyamide membrane. Preferential sorption of water over alcohol was observed in the membrane. As alcohol concentration in the solution increases, the sorption selectivity of water over methanol increases from 4 to 375, whereas the sorption selectivity water over isopropanol increases only from 2 to 8. However, as water is nonsolvent for polyamide, the membrane surface structure remains unaffected by the water sorption. On the other hand, the sorption of alcohol in the membrane leads to decrease in characteristic IR band intensities of the polyamide implying a change in membrane surface structure which corroborates with the change in membrane surface roughness as observed by atomic force microscopy (AFM) and scanning electron microscopy (SEM) images. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Impact and prospective of fungal pre‐treatment of lignocellulosic biomass for enzymatic hydrolysis
Authors: Tian Xiao‐fei , Fang Zhen , Guo Feng
Published: January 2012

The presence of lignin in lignocellulosic biomass leads to a protective barrier which prevents enzymes from being accessible to cellulose and hemicellulose for hydrolysis. As a result, pre‐treatment is a ‘must’ step for subsequent enzymatic hydrolysis. Bio pre‐treatment is normally conducted at low temperatures and low pressures without using expensive equipment, chemical agents, reactors, and additional energy for lignin removal and biomass structure destruction. Therefore, it is a green, safe, and inexpensive method. White‐rot fungi (WRF), a group of fungi (more than 1500 different species) are successfully applied in bioconversion processes such as sewage treatment, biopulping, conversion of forest and agricultural residues to animal feeds, and the production of edible or medicinal mushrooms. In the bio pre‐treatment process, WRF are mostly used for secreting ligninolytic enzymes, a variety of donor substrates and selective degradation of lignin. Current research related to WRF bio pre‐treatment is mainly focusing on the following four aspects: (i) selection of candidate strains for certain biomass materials; (ii) optimization of cultivation methods; (iii) characterization of fungal treated materials; and (iv) evaluation of combining bio pre‐treatment with chemical or physicochemical approaches. Future prospects and recommended research work on applying WRF in bio pre‐treatment are also briefly introduced and summarized in this review. These include (i) integrated methods (i.e. co‐treatment with organic solvents, diluted acids, supercritical CO2 and ionic liquids) to resolve problems existing in fungal pre‐treatment applications; (ii) mutation breeding and crossbreeding of fungal mycelia to obtain engineering strains; and (iii) integration of fungal pre‐treatment with simultaneous saccharification and fermentation to produce biofuels and value‐added products. © 2012 Society of Chemical Industry and John Wiley & Sons, Ltd
RGB Small Molecules Based on a Bipolar Molecular Design for Highly Efficient Solution‐Processed Single‐layer OLEDs
Authors: Yao Liang , Xue Shanfeng , Wang Qi , Dong Wenyue , Yang Wei , Wu Hongbin , Zhang Ming , Yang Bing , Ma Yuguang
Published: January 2012

In this paper, we describe a bipolar molecular design for small molecule solution‐processed organic light emitting diodes (OLEDs). Combining the rigidity of the conjugated emissive cores and the flexibility of the peripheral alkyl‐linked carbazole groups, two series of highly efficient bipolar RGB (red, green, blue) emitters have been synthesized and characterized. The emissive cores are composed of electron‐withdrawing groups; the carbazole groups endow the materials electron‐donating units. Such bipolar structures are advantageous for the carrier injection and balance. Four peripheral carbazole groups are introduced in T‐series materials (TCDqC, TCSoC, TCBzC, TCNzC), and another four in O‐series materials (OCDqC, OCSoC, OCBzC, OCNzC). With the single‐layer device configuration of ITO/PEDOT:PSS/emitting layer/CsF/Al, two green devices exhibited excellent performance with a maximum luminescence efficiency of over 6.4 cd A−1, and a high maximum luminance of more than 6700 cd m−2. In addition, compared with the T‐series, the luminescence efficiency of blue and red devices based on O‐series materials increased from 1.6 to 2.8 cd A−1 and 0.2 to 1.3 cd A−1, respectively. To our knowledge, the performance of the blue device based on OCSoC is among the best of the blue small‐molecule solution‐processed single‐layer devices reported so far.
pH‐Tunable Hydrogelators for Water Purification: Structural Optimisation and Evaluation
Authors: Wood Daniel M. , Greenland Barnaby W. , Acton Aaron L. , Rodríguez‐Llansola Francisco , Murray Claire A. , Cardin Christine J. , Miravet Juan F. , Escuder Beatriu , Hamley Ian W. , Hayes Wayne
Published: January 2012

A focused library of potential hydrogelators each containing two substituted aromatic residues separated by a urea or thiourea linkage have been synthesised and characterized. Six of these novel compounds are highly efficient hydrogelators, forming gels in aqueous solution at low concentrations (0.03–0.60 wt %). Gels were formed through a pH switching methodology, by acidification of a basic solution (pH 14 to ≈4) either by addition of HCl or via the slow hydrolysis of glucono‐δ‐lactone. Frequently, gelation was accompanied by a dramatic switch in the absorption spectra of the gelators, resulting in a significant change in colour, typically from a vibrant orange to pale yellow. Each of the gels was capable of sequestering significant quantities of the aromatic cationic dye, methylene blue, from aqueous solution (up to 1.02 g of dye per gram of dry gelator). Cryo‐transmission electron microscopy of two of the gels revealed an extensive network of high aspect ratio fibers. The structure of the fibers altered dramatically upon addition of 20 wt % of the dye, resulting in aggregation and significant shortening of the fibrils. This study demonstrates the feasibility for these novel gels finding application as inexpensive and effective water purification platforms.
Rare‐Earth‐Metal–Hydrocarbyl Complexes Bearing Linked Cyclopentadienyl or Fluorenyl Ligands: Synthesis, Catalyzed Styrene Polymerization, and Structure–Reactivity Relationship
Authors: Jian Zhongbao , Cui Dongmei , Hou Zhaomin
Published: January 2012

A series of rare‐earth‐metal–hydrocarbyl complexes bearing N‐type functionalized cyclopentadienyl (Cp) and fluorenyl (Flu) ligands were facilely synthesized. Treatment of [Y(CH2SiMe3)3(thf)2] with equimolar amount of the electron‐donating aminophenyl‐Cp ligand C5Me4H‐C6H4‐o‐NMe2 afforded the corresponding binuclear monoalkyl complex [({C5Me4‐C6H4‐o‐NMe(μ‐CH2)}Y{CH2SiMe3})2] (1 a) via alkyl abstraction and CH activation of the NMe2 group. The lutetium bis(allyl) complex [(C5Me4‐C6H4‐o‐NMe2)Lu(η3‐C3H5)2] (2 b), which contained an electron‐donating aminophenyl‐Cp ligand, was isolated from the sequential metathesis reactions of LuCl3 with (C5Me4‐C6H4‐o‐NMe2)Li (1 equiv) and C3H5MgCl (2 equiv). Following a similar procedure, the yttrium‐ and scandium–bis(allyl) complexes, [(C5Me4‐C5H4N)Ln(η3‐C3H5)2] (Ln=Y (3 a), Sc (3 b)), which also contained electron‐withdrawing pyridyl‐Cp ligands, were also obtained selectively. Deprotonation of the bulky pyridyl‐Flu ligand (C13H9‐C5H4N) by [Ln(CH2SiMe3)3(thf)2] generated the rare‐earth‐metal–dialkyl complexes, [(η3‐C13H8‐C5H4N)Ln(CH2SiMe3)2(thf)] (Ln=Y (4 a), Sc (4 b), Lu (4 c)), in which an unusual asymmetric η3‐allyl bonding mode of Flu moiety was observed. Switching to the bidentate yttrium–trisalkyl complex [Y(CH2C6H4‐o‐NMe2)3], the same reaction conditions afforded the corresponding yttrium bis(aminobenzyl) complex [(η3‐C13H8‐C5H4N)Y(CH2C6H4‐o‐NMe2)2] (5). Complexes 1–5 were fully characterized by 1H and 13C NMR and X‐ray spectroscopy, and by elemental analysis. In the presence of both [Ph3C][B(C6F5)4] and AliBu3, the electron‐donating aminophenyl‐Cp‐based complexes 1 and 2 did not show any activity towards styrene polymerization. In striking contrast, upon activation with [Ph3C][B(C6F5)4] only, the electron‐withdrawing pyridyl‐Cp‐based complexes 3, in particular scandium complex 3 b, exhibited outstanding activitiy to give perfectly syndiotactic (rrrr >99 %) polystyrene, whereas their bulky pyridyl‐Flu analogues (4 and 5) in combination with [Ph3C][B(C6F5)4] and AliBu3 displayed much‐lower activity to afford syndiotactic‐enriched polystyrene.
Long‐term outcome of the treatment of high‐risk tenosynovial giant cell tumor/pigmented villonodular synovitis with radiotherapy and surgery
Authors: Griffin Anthony M. , Ferguson Peter C. , Catton Charles N. , Chung Peter W. M. , White Lawrence M. , Wunder Jay S. , Bell Robert S. , O'Sullivan Brian
Published: January 2012

BACKGROUND:

The treatment of diffuse tenosynovial giant cell tumor (TGCT) requires extensive surgical resection of the hypertrophic synovium and multiple soft tissue masses yet still may result in high rates of local failure. The authors of this report examined their experience in treating patients with advanced/multiply recurrent TGCT with a combination of surgery and external‐beam radiotherapy.

METHODS:

Fifty patients who were treated for TGCT with radiotherapy and surgery from 1972 to 2006 were identified. Patient demographics, radiotherapy treatment parameters, surgical treatment, and oncologic and functional outcomes were evaluated. All patients had pathologic review at presentation and required at least 1 year follow‐up.

RESULTS:

Forty‐nine patients had diffuse TGCT with both intra‐articular and extra‐articular disease (1 had malignant TGCT). Twenty‐eight patients (56%) were referred after at least 1 local recurrence. Thirty patients (60%) underwent at least 2 operations before radiotherapy. The mean dose of radiation delivered was 39.8 gray. At a mean follow‐up of 94 months (range, 19‐330 months), 47 patients (94%) had not developed a recurrence or had stable disease/signal characteristics on serial cross‐sectional imaging (for those patients who had gross residual disease at the time of radiotherapy). Two patients required subsequent total hip arthroplasty because of progressive osteoarthritis, and there were 4 cases of avascular necrosis (only 1 post‐treatment). Forty‐one patients had good/excellent function.

CONCLUSIONS:

For patients with extensive or multiple local relapses or when surgery alone would result in a large burden of residual disease or major functional loss, the addition of moderate‐dose adjuvant radiotherapy provided excellent local control while maintaining good function with low treatment‐related morbidity. Cancer 2012. © 2012 American Cancer Society.
Oncogene status predicts patterns of metastatic spread in treatment‐naive nonsmall cell lung cancer
Authors: Doebele Robert C. , Lu Xian , Sumey Christopher , Maxson DeLee A. , Weickhardt Andrew J. , Oton Ana B. , Bunn Paul A. , Barón Anna E. , Franklin Wilbur A. , Aisner Dara L. , Varella‐Garcia Marileila , Camidge D. Ross
Published: January 2012

BACKGROUND:

The discovery of distinct subsets of nonsmall cell lung cancer (NSCLC) characterized by activation of driver oncogenes has greatly affected personalized therapy. It is hypothesized that the dominant oncogene in NSCLC would be associated with distinct patterns of metastatic spread in NSCLC at the time of diagnosis.

METHODS:

A total of 209 consecutive patients with stage IV nonsquamous NSCLC with an EGFR (epidermal growth factor receptor) mutation (N = 39), KRAS (v‐Ki‐ras2 Kirsten rat sarcoma viral oncogene homolog) mutation (N = 49), ALK (anaplastic lymphoma receptor tyrosine kinase) gene rearrangement (N = 41), or wild‐type for all 3 (triple negative, N = 80) were included. The percentage of patients with metastatic disease at a given site was compared between each molecular cohort (EGFR, KRAS, or ALK) and the triple negative cohort.

RESULTS:

ALK gene rearrangement was significantly associated with pericardial disease (odds ratio [OR] = 4.61; 95% confidence interval [CI] = 1.30, 16.37; P = .02) and pleural disease (OR = 4.80; 95% CI = 2.10, 10.97; P < .001). Patients with ALK gene rearrangements (OR = 5.50; 95% CI = 1.76, 17.18; P = .003) and patients with EGFR mutations (OR = 5.17; 95% CI = 1.63, 16.43; P = .006) were predisposed to liver metastasis compared to the triple negative cohort. No molecular cohort had a predisposition to pulmonary nodules, or adrenal, bone, or brain metastasis compared to the triple negative cohort. The mean number of metastatic disease sites in patients within the ALK rearranged cohort was significantly greater than that of the triple negative cohort (mean = 3.6 sites vs 2.5 sites, P < .0001).

CONCLUSIONS:

The results support the hypothesis that the dominant molecular oncogenes in NSCLC are associated with different biological behaviors manifesting as distinct patterns of metastatic spread at the time of diagnosis. Cancer 2012. © 2012 American Cancer Society.
Correlations between the percentage of tumor cells showing an anaplastic lymphoma kinase (ALK) gene rearrangement, ALK signal copy number, and response to crizotinib therapy in ALK fluorescence in situ hybridization–positive nonsmall cell lung cancer
Authors: Camidge D. Ross , Theodoro Mariana , Maxson DeLee A. , Skokan Margaret , O'Brien Tara , Lu Xian , Doebele Robert C. , Barón Anna E. , Varella‐Garcia Marileila
Published: January 2012

BACKGROUND:

Fluorescence in situ hybridization (FISH), using break‐apart red (3′) and green (5′) ALK (anaplastic lymphoma kinase) probes, consistently shows rearrangements in <100% of tumor cells in ALK‐positive (ALK+) nonsmall cell lung cancer (NSCLC). Increased copy numbers of fused and rearranged signals also occur. Here, correlations are explored between the percentage of ALK+ cells and signal copy number and their association with response to ALK inhibition.

METHODS:

Ninety ALK+ NSCLC cases were evaluated. The percentage of positive cells, pattern of positivity (split, single red, or both), and copy number of fused, isolated red and green signals were recorded. Thirty patients had received crizotinib.

RESULTS:

Increased isolated red signal copy number (contributing to both single red and split patterns of positivity) correlated with a higher percentage of ALK+ cells (r = 0.743, P < .0001). Mean fused copy number was negatively associated with isolated red signal copy number (r = −0.409, P < .0001). Neither percentage of positive cells (r = 0.192, P = .3), nor copy number of isolated red signal (r = 0.274, P = .195) correlated with maximal tumor shrinkage with crizotinib.

CONCLUSIONS:

The strong association between increased copy number of key ALK signals and percentage of positive cells suggests that the <100% rate of cellular positivity in ALK+ tumors is due to technical factors, not biological factors. In ALK+ tumors, neither the percentage of positive cells nor signal copy number appear to be informative variables for predicting benefit from ALK inhibition. The inverse relationship between fused and isolated red copy number suggests ALK+ may be a distinct “near‐diploid” subtype of NSCLC that develops before significant chromosomal aneusomy occurs. Cancer 2012. © 2012 American Cancer Society.
Prognostic implication of metastasis limited to segmental (level 13) and/or subsegmental (level 14) lymph nodes in patients with surgically resected nonsmall cell lung carcinoma and pathologic N1 lymph node status
Authors: Maeshima Akiko Miyagi , Tsuta Koji , Asamura Hisao , Tsuda Hitoshi
Published: January 2012

BACKGROUND:

In patients with nonsmall cell lung carcinoma (NSCLC) who have with pathologic N1 (pN1) lymph node status, the prognostic significance of segmental lymph node (level 13) metastasis and/or subsegmental lymph node (level 14) metastasis is unknown.

METHODS:

Lymph node metastasis patterns were analyzed in 230 patients with NSCLC who had pN1 status. Clinical outcomes were examined for 230 patients with pN1 status and 700 patients with pN0 status. The pN1 group was stratified into 4 subgroups according to the highest level of lymph node involvement.

RESULTS:

The 5‐year disease‐free survival (5DFS) rates for pN1 and pN0 patients were 50.1% and 90.5%, respectively. The highest level of lymph node involvement was a significant prognostic indicator; the 5DFS rates for patients with pN1 status who had level 13/14, lobar (level 12), interlobar (level 11), and hilar (level 10) lymph node metastasis were 69.4%, 46.4%, 46.7%, and 37%, respectively. Patient outcomes were significantly worse for those with pN1 status who had only level 13/14 lymph node metastasis than for patients with pN0 status (P = .0034), and outcomes were significantly worse for patients with pN1 status who had level 11/12 lymph node metastasis than for patients who had only level 13/14 lymph node metastasis (P = .021). The median number of level 13/14 lymph nodes examined was 3 (range, 0‐22 level 13/14 lymph nodes), and metastases to these lymph nodes were detected in 61% of patients who had pN1 status. A single lymph node pN1 disease, single‐level pN1 status, and squamous cell carcinoma histopathology also were indicators of a better patient outcome.

CONCLUSIONS:

The current results indicated that the highest level of lymph node involvement may be used to stratify the outcome of patients who have NSCLC with pN1 status. Patients with pN1 status who had only level 13/14 lymph node metastasis had an intermediate 5DFS rate between that of patients with pN0 status and other patients with pN1 status. Routine examination of level 13/14 lymph nodes is important for accurate pathologic staging and for the predicting clinical outcome of patients with NSCLC. Cancer 2012. © 2012 American Cancer Society.
Identification of candidate genes carrying polymorphisms associated with the risk of colorectal cancer by analyzing the colorectal mutome and microRNAome
Authors: Landi Debora , Gemignani Federica , Pardini Barbara , Naccarati Alessio , Garritano Sonia , Vodicka Pavel , Vodickova Ludmila , Canzian Federico , Novotny Jan , Barale Roberto , Landi Stefano
Published: January 2012

BACKGROUND:

The presence of single‐nucleotide polymorphisms (SNPs) within the 3′‐untranslated regions of genes could affect the binding between a microRNA (miRNA) and its target, with consequences on gene expression regulation. Considering the important role of miRNAs in carcinogenesis, it is hypothesized here that these SNPs could also affect the individual risk of colorectal cancer (CRC).

METHODS:

To test this hypothesis, a list was developed of 140 somatically mutated genes deduced from previous works on the mutome of the CRC. A further selection was conducted of SNPs within target sites for miRNAs that are expressed only in the colorectum (the colorectal microRNAome) and having adequate population frequencies. This yielded 12 SNPs that were genotyped in a case‐control association study on 717 colorectal cases and 1171 controls from the Czech Republic.

RESULTS:

Statistically significant associations were found between the risk of CRC and the variant alleles of KIAA0182 (rs709805) (odds ratio = 1.57; 95% confidence interval = 1.06‐2.78, for the variant homozygotes) and NUP210 genes (rs354476) (odds ratio = 1.36; 95% confidence interval = 1.02‐1.82, for the variant homozygotes).

CONCLUSIONS:

The results support the study hypothesis and highlight the importance of SNPs within miRNA‐dependent regulatory regions. Further studies on the role exerted by NUP210 and KIAA0182 in colorectal carcinogenesis are warranted. Cancer 2012. © 2012 American Cancer Society.
Measuring the overhead of Intel C++ Concurrent Collections over Threading Building Blocks for Gauss–Jordan elimination
Authors: Tang Peiyi
Published: January 2012

The most efficient way to parallelize computation is to build and evaluate the task graph constrained only by the data dependencies between the tasks. Both Intel's C++ Concurrent Collections (CnC) and Threading Building Blocks (TBB) libraries allow such task‐based parallel programming. CnC also adapts the macro data flow model by providing only single‐assignment data objects in its global data space. Although CnC makes parallel programming easier, by specifying data flow dependencies only through single‐assignment data objects, its macro data flow model incurs overhead. Intel's C++ CnC library is implemented on top of its C++ TBB library. We can measure the overhead of CnC by comparing its performance with that of TBB. In this paper, we analyze all three types of data dependencies in the tiled in‐place Gauss–Jordan elimination algorithm for the first time. We implement the task‐based parallel tiled Gauss–Jordan algorithm in TBB using the data dependencies analyzed and compare its performance with that of the CnC implementation. We find that the overhead of CnC over TBB is only 12%– 15% of the TBB time, and CnC can deliver as much as 87%– 89% of the TBB performance for Gauss–Jordan elimination, using the optimal tile size. Copyright © 2012 John Wiley & Sons, Ltd.
Flexible and energy‐efficient duty cycling in wireless networks with MacZ
Authors: Christmann Dennis , Gotzhein Reinhard , Krämer Marc , Winkler Martin
Published: January 2012

In wireless networks formed of battery‐powered nodes, energy consumption is a major concern. On the communication side, energy can be saved by switching transceivers to idle or power‐down mode when not needed. To this end, duty cycling protocols located at medium access control level have been devised. These protocols have in common that they define modified carrier sense multiple access with collision avoidance schemes and that they assume the availability of some time synchronization mechanism. This strongly limits their potential to reduce energy consumption, as well as their flexibility regarding activity phases. In this paper, we propose a more flexible and energy‐efficient solution for duty cycling, which is based on our experimental wireless medium access control protocol MacZ. Flexibility is strengthened by the possibility to define weakly periodic activity periods. Energy efficiency is improved by the possibility to assign exclusive transmission slots, thereby switching transceivers to active mode only when needed. Both measures are supported by an underlying protocol for accurate, deterministic tick and time synchronization. We assess our solution and compare it to well‐known duty cycling protocols on the basis of real‐life scenarios. Copyright © 2012 John Wiley & Sons, Ltd.