bluuebunny/crossref_metadata_2025 huggingface dataset:
Metabolism of Halogenated Alkanes by Cytochrome P450 enzymes. Aerobic Oxidation versus Anaerobic Reduction
Authors: Ji Li , Zhang Jing , Liu Weiping , de Visser Sam P.
Published: February 2014

The cytochromes P450 are a large class of heme‐containing enzymes that catalyze a broad range of chemical reactions in biosystems, mainly through oxygen‐atom transfer to substrates. A relatively unknown reaction catalyzed by the P450s, but very important for human health, is the activation of halogenated substrates, which may lead to toxicity problems. However, its catalytic mechanism is currently unknown and, therefore, we performed a detailed computational study. To gain insight into the metabolism of halogenated compounds by P450 enzymes, we have investigated the oxidative and reductive P450‐mediated activation of tetra‐ and trichloromethane as halogenated models with density functional theory (DFT) methods. We propose an oxidative halosylation mechanism for CCl4 under aerobic conditions by Compound I of P450, which follows the typical Groves‐type rebound mechanism. By contrast, the metabolism of CHCl3 occurs preferentially via an initial hydrogen‐atom abstraction rather than halosylation. Kinetic isotope effect studies should, therefore, be able to distinguish the mechanistic pathways of CCl4 versus CHCl3. We find a novel mechanism that is different from the well accepted P450 substrate activation mechanisms reported previously. Moreover, the studies highlight the substrate specific activation pathways by P450 enzymes leading to different products. These reactivity differences are rationalized using Marcus theory equations, which reproduce experimental product distributions.
Evidence of a LNOX influence on middle/upper troposphere ozone‐mixing ratios at Dakar, Senegal during Northern Hemisphere summer season
Authors: Jenkins Gregory S. , Gueye Moussa , Drame Mamadou S. , Ndiaye Seydi A.
Published: February 2014

We present results for the vertical distribution of tropospheric ozone from 40 measurements at Dakar, Senegal (14.59°N, 17.5°W) from June to September of 2008, 2010, 2011 and 2012. Under pre‐monsoon conditions (June), many dry air intrusions are found in the lower troposphere transitioning to humid conditions during July, August and September. Measurements show the highest ozone‐mixing ratios (50–100 ppb) in the 400–200 hPa layer and easterly wind flow during each month. Lightning‐NOX (LNOX) is the only viable source to explain the vertical distribution of ozone, with a large amount of upstream lightning over West Africa during summer.
George Box and Bayesian inference
Authors: Meyer R. Daniel
Published: February 2014

The Bayesian paradigm was fundamental to George Box's philosophy of statistics. Box's scholarship in statistics was driven by his engagement with other scientists in the process of scientific discovery. In his view, scientific discovery was represented elegantly by Bayes' theorem, in which information from the latest experiment is combined with current knowledge. Applications to real problems was the focus of his research in Bayesian methods, especially problems that were less accessible to classical methods based on sampling theory. These problems typically related to the design of experiments and analysis of experimental data, hierarchical models, the sensitivity of inferences to assumptions about the data, and the use of non‐informative priors. His work with a network of collaborators laid the groundwork for widespread application of Bayesian methods facilitated by later advances in computational methods. Copyright © 2014 John Wiley & Sons, Ltd.
Natural products – learning chemistry from plants
Authors: Staniek Agata , Bouwmeester Harro , Fraser Paul D. , Kayser Oliver , Martens Stefan , Tissier Alain , van der Krol Sander , Wessjohann Ludger , Warzecha1 Heribert
Published: February 2014

Plant natural products (PNPs) are unique in that they represent a vast array of different structural features, ranging from relatively simple molecules to very complex ones. Given the fact that many plant secondary metabolites exhibit profound biological activity, they are frequently used as fragrances and flavors, medicines, as well as industrial chemicals. As the intricate structures of PNPs often cannot be mimicked by chemical synthesis, the original plant providers constitute the sole source for their industrial, large‐scale production. However, sufficient supply is not guaranteed for all molecules of interest, making the development of alternative production systems a priority. Modern techniques, such as genome mining and thorough biochemical analysis, have helped us gain preliminary understanding of the enzymatic formation of the valuable ingredients in planta. Herein, we review recent advances in the application of biocatalytical processes, facilitating generation of complex PNPs through utilization of plant‐derived specific enzymes and combinatorial biochemistry. We further evaluate the options of employing heterologous organisms harboring PNP biosynthetic pathways for the production of secondary metabolites of interest.
Peptide microarrays enable rapid mimotope optimization for pharmacokinetic analysis of the novel therapeutic antibody IMAB362
Authors: Schnatbaum Karsten , Schmoldt Hans‐Ulrich , Daneschdar Matin , Plum Laura M. , Jansong Janina , Zerweck Johannes , Kühne Yvonne , Masch Antonia , Wenschuh Holger , Fiedler Markus , Türeci Özlem , Sahin Ugur , Reimer Ulf
Published: February 2014

As membrane proteins play an important role in a variety of life‐threatening diseases, the development of therapeutic monoclonal antibodies against membrane proteins is of significant interest. Among many other requirements, the process of antibody drug development requires a set of tailor‐made assays for the characterization of the antibodies and for monitoring their activity. Designing assays to characterize antibodies directed to membrane proteins is challenging, because the natural targets are often not available in a format that is compatible with a biochemical assay setup. Thus, alternatives that mimic the targeted membrane proteins are needed. In this study, we developed optimal peptidic mimotopes for the ELISA‐based detection of the novel therapeutic antibody IMAB362 in biological samples. Initial hits were identified using phage display and these hits were optimized with the help of structure‐activity relationship analysis on peptide microarrays. The optimized peptides showed binding constants in the low nanomolar to picomolar range, an improvement by a factor of up to 30 compared to the initial hits. The best mimotope (apparent KD = 0.15 nM) was successfully used for the ELISA‐based quantification of IMAB362 in samples from a mouse pharmacokinetic study. The process described allows the rapid discovery of mimotopes for target proteins that are difficult to produce or handle, which can then be used in pre‐clinical and clinical assays or for the purification of biological products.
Lanthanoid–Transition‐Metal Bonding in Bismetallocenes
Authors: Butovskii Mikhail V. , Oelkers Benjamin , Bauer Tobias , Bakker Jacinta M. , Bezugly Viktor , Wagner Frank R. , Kempe Rhett
Published: February 2014

Bismetallocenes [Cp2LuReCp2] and [Cp*2LaReCp2] (Cp=cyclopentadienyl; Cp*=pentamethylcyclopentadienyl) were prepared using different synthetic strategies. Salt metathesis—performed in aromatic hydrocarbons to avoid degradation pathways caused by THF—were identified as an attractive alternative to alkane elimination. Although alkane elimination is more attractive in the sense of its less elaborate workup, the rate of the reaction shows a strong dependence on the ionic radius of Ln3+ (Ln=lanthanide) within a given ligand set. Steric hindrance can cause a dramatic decrease in the reaction rate of alkane elimination. In this case, salt metathesis should be considered the better alternative. Covalent bonding interactions between the Ln and transition‐metal (TM) cations has been quantified on the basis of the delocalization index. Its magnitude lies within the range characteristic for bonds between transition metals. Secondary interactions were identified between carbon atoms of the Cp ligand of the transition metal and the Ln cation. Model calculations clearly indicated that the size of these interactions depends on the capability of the TM atom to act as an electron donor (i.e., a Lewis base). The consequences can even be derived from structural details. The observed clear dependency of the LuRu and interfragment LuC bonding on the THF coordination of the Lu atom points to a tunable Lewis acidity at the Ln site, which provides a method of significantly influencing the structure and the interfragment bonding.
Aptamer‐Based Luminescence Energy Transfer from Near‐Infrared‐to‐Near‐Infrared Upconverting Nanoparticles to Gold Nanorods and Its Application for the Detection of Thrombin
Authors: Yuan Fei , Chen Hongqi , Xu Juan , Zhang Yiyan , Wu Yong , Wang Lun
Published: February 2014

A new luminescence energy transfer (LET) system has been designed for the detection of thrombin in the near‐infrared (NIR) region by utilizing NIR‐to‐NIR upconversion lanthanide nanophosphors (UCNPs) as the donor and gold nanorods (Au NRs) as the acceptor. The use of upconverting NaYF4:Yb3+,Tm3+ nanoparticles with sharp NIR emission peaks upon NIR excitation by an inexpensive infrared continuous wave laser diode provided large spectral overlap between the donor and the acceptor. Both the Au NRs and carboxyl‐terminated NaYF4:Yb3+,Tm3+ UCNPs were first modified with different thrombin aptamers. When thrombin was added, a LET system was then formed because of the specific recognition between the thrombin aptamers and thrombin. The LET system was used to monitor thrombin concentrations in aqueous buffer and human blood samples. The limits of detection for thrombin are as low as 0.118 nM in buffer solution and 0.129 nM in human serum. The method was also successfully applied to thrombin detection in blood samples.
Palladium/Copper‐Catalyzed Oxidative Arylation of Terminal Alkenes with Aroyl Hydrazides
Authors: Zhang Yong‐Gang , Liu Xiang‐Lei , He Zeng‐Yang , Li Xi‐Ming , Kang Hong‐Jian , Tian Shi‐Kai
Published: February 2014

An unprecedented oxidative arylation reaction of terminal alkenes with simple aroyl hydrazides has been developed under aerobic conditions for the stereoselective synthesis of 1,2‐disubstituted alkenes. A range of aroyl hydrazides underwent palladium/copper‐catalyzed oxidative Mizoroki–Heck reaction with terminal alkenes open to air in a 1:1 mixture of dimethyl sulfoxide and acetonitrile to give structurally diverse 1,2‐disubstituted alkenes in moderate to excellent yields with excellent regio‐ and E‐selectivity. The reaction tolerated a wide variety of functional groups, such as alkoxy, hydroxy, amino, fluoro, chloro, bromo, cyano, nitro, ester, amide, imide, phosphine oxide, and sulfone groups, and, moreover, molecular oxygen and dimethyl sulfoxide were demonstrated to serve as terminal oxidants. This study provides a useful method for the stereoselective synthesis of 1,2‐disubstituted alkenes through direct transformation of the vinylic CH bonds in terminal alkenes.
Mein Weg zum Wissenschaftsjournalismus
Authors: Groß Michael
Published: February 2014

Dem Wissenschaftsjournalismus kommt angesichts der rasanten Fortschritte in Wissenschaft und Technik eine wichtige Rolle zu. Die freiberufliche Tätigkeit in diesem Bereich bietet zwar wenig finanzielle Sicherheit aber viel kreativen Spielraum. Neugier und Freude am Schreiben sind die wichtigsten Qualifikationen.
Stickstoffreduktion mit Titan‐Clustern
Authors: Jaenicke Lothar
Published: February 2014

Stickstoff (genauer Distickstoff, N2) ist ein sehr inertes Element, daher das verbreitetste auf Erden. Und doch ist es in reduzierter Form als Ammoniak (NH3) lebenswichtig zur Biosynthese der Protein‐Aminosäuren und ihrer direkten Polymerisate, den Biostrukturmaterialien (Proteine und Bindegewebe) oder indirekten Abkömmlinge, den hochmolekularen Biokatalysatoren (Enzyme) und niedermolekularen Biowirkstoffen (Vitamine, Hormone, Signalstoffe). Ohne mikrobiell oder chemisch fixierten Stickstoff geht nichts in dieser Welt.
Characterization of Dry‐Spun Acrylic Fiber Wastewater by Particle Size Distribution, Biodegradability, and Chemical Composition
Authors: Wang Qinghong , Yan Guangxu , Cai Bin , Chen Chunmao , Guo Shaohui
Published: February 2014

Dry‐spun acrylic fiber wastewater of large volume, high organic concentration, and low biodegradability is difficult to be treated by traditional treatment process. Detailed characterization of the wastewater is necessary to provide valuable information on designing effective treatment processes. The objective of this paper was to investigate particle size distribution and the associated biodegradability and chemical composition of dry‐spun acrylic fiber wastewater. For this purpose, gradient membrane separation was carried out, the evaluation of biochemical oxygen demand over a 5‐day period/chemical oxygen demand (COD) and tetrazolium chloride‐dehydrogenase activity was investigated and analysis of Fourier transform infrared spectroscopy, gas chromatography‐mass spectrometry and electrospray ionization‐Fourier transform ion cyclotron resonance mass spectrometer was characterized. It is appeared that the particles are consecutive distributed in the wastewater. The main pollutants are soluble organics accounting for 61.4% of COD, followed by colloidal compounds (25.7% COD) and settleable/supracolloidal compounds (12.9% COD). The organics distributed in the range of 2–10 nm are easily to be biodegraded, but soluble and settleable/supracolloidal fractions are biorefractory. The reason could be high molecular polymers containing NH, OH, CO groups were exited in the settleable/supracolloidal fractions, and some toxic components including C6H6N2, C7H8O2, and some NSO heterocycles were dissolved in the soluble fractions. The results indicated that removing the settleable or supracolloidal substances and improving biodegradability of the soluble organics by pretreatment are necessary for the treatment of dry‐spun acrylic fiber wastewater.
A new directionality tool for assessing microtubule pattern alterations
Authors: Liu Wenhua , Ralston Evelyn
Published: February 2014

The cytoskeleton (microtubules, actin and intermediate filaments) has a cell type‐specific spatial organization that is essential and reflects cell health. We are interested in understanding how changes in the organization of microtubules contribute to muscle diseases such as Duchenne muscular dystrophy (DMD). The grid‐like immunofluorescence microtubule pattern of fast‐twitch muscle fibers lends itself well to visual assessment. The more complicated pattern of other fibers does not. Furthermore, visual assessment is not quantitative. Therefore we have developed a robust software program for detecting and quantitating microtubule directionality. Such a tool was necessary because existing methods focus mainly on local image features and are not well suited for microtubules. Our tool, texture detection technique (TeDT), is based on the Haralick texture method and takes into account both local and global features with more weight on the latter. The results are expressed in a graphic form responsive to subtle variations in microtubule distribution, while a numerical score allows quantitation of directionality. Furthermore, the results are not affected by imaging conditions or post‐imaging procedures. TeDT successfully assesses test images and microtubules in fast‐twitch fibers of wild‐type and mdx mice (a model for DMD); TeDT also identifies and quantitates microtubule directionality in slow‐twitch fibers, in the fibers of young animals, and in other mouse models which could not be assessed visually. TeDT might also contribute to directionality assessments of other cytoskeletal components. Published 2014 Wiley Periodicals Inc. This article is a US government work and, as such, is in the public domain in the United States of America.
Synthesis, Antimalarial Properties, and SAR Studies of Alkoxyurea‐Based HDAC Inhibitors
Authors: Hansen Finn K. , Skinner‐Adams Tina S. , Duffy Sandra , Marek Linda , Sumanadasa Subathdrage D. M. , Kuna Krystina , Held Jana , Avery Vicky M. , Andrews Katherine T. , Kurz Thomas
Published: February 2014

Histone deacetylase (HDAC) inhibitors are an emerging class of potential antimalarial drugs. We investigated the antiplasmodial properties of 16 alkoxyurea‐based HDAC inhibitors containing various cap and zinc binding groups (ZBGs). Ten compounds displayed sub‐micromolar activity against the 3D7 line of Plasmodium falciparum. Structure–activity relationship studies revealed that a hydroxamic acid ZBG is crucial for antiplasmodial activity, and that the introduction of bulky alkyl substituents to cap groups increases potency against asexual blood‐stage parasites. We also demonstrate that selected compounds cause hyperacetylation of P. falciparum histone H4, indicating inhibition of one or more PfHDACs. To assess the selectivity of alkoxyurea‐based HDAC inhibitors for parasite over normal mammalian cells, the cytotoxicity of representative compounds was evaluated against neonatal foreskin fibroblast (NFF) cells. The most active compound, 6‐((3‐(4‐(tert‐butyl)phenyl)ureido)oxy)‐N‐hydroxyhexanamide (1 e, Pf3D7 IC50: 0.16 μM) was 31‐fold more toxic against the asexual blood stages than towards normal mammalian cells. Moreover, a subset of four structurally diverse HDAC inhibitors revealed moderate activity against late‐stage (IV–V) gametocytes.
Synthetic Chromatin Approaches To Probe the Writing and Erasing of Histone Modifications
Authors: Fierz Beat
Published: February 2014

Posttranslational modifications (PTMs) of chromatin are involved in gene regulation, thereby contributing to cell differentiation, lineage determination, and organism development. Discrete chromatin states are established by the action of a large set of enzymes that catalyze the deposition, propagation, and removal of histone PTMs, thereby modulating gene expression. Given their central role in determining and maintaining cellular phenotype, as well as in controlling chromatin processes such as DNA repair, the dysregulation of these enzymes can have serious consequences, and can result in cancer and neurodegenerative diseases. Thus, such chromatin regulator proteins are promising drug targets. However, they are often present in large, modular protein complexes that specifically recognize target chromatin regions and exhibit intricate regulation through preexisting histone marks. This renders the study of their enzymatic mechanisms complex. Recent developments in the chemical production of defined chromatin substrates show great promise for improving our understanding of the activity of chromatin regulator complexes at the molecular level. Herein I discuss examples highlighting the application of synthetic chromatin to study the enzymatic mechanisms and regulatory pathways of these crucial protein complexes in detail, with potential implications for assay development in pharmacological research.
Efficient Plasmonic Dye‐Sensitized Solar Cells with Fluorescent Au‐Encapsulated C‐Dots
Authors: Narayanan Remya , Deepa Melepurath , Srivastava Avanish Kumar , Shivaprasad Sonnada Math
Published: February 2014

A simple strategy to improve the efficiency of a ZnO‐nanorod‐based dye‐sensitized solar cell (DSSC) by use of Au‐encapsulated carbon dots (Au@C‐dots) in the photoanode is presented. The localized surface plasmonic resonance of Au in the 500–550 nm range coupled with the ability of C‐dots to undergo charge separation increase the energy‐harvesting efficiency of the DSSC with ZnO/N719/Au@C‐dots photoanodes. Charge transfer from N719 dye to Au@C‐dots is confirmed by fluorescence and lifetime enhancements of Au@C‐dots. Forster resonance energy transfer (FRET) from the gap states of ZnO nanorods to N719 dye is also ratified and the energy transfer rate is 4.4×108 s−1 and the Forster radius is 1.89 nm. The overall power conversion efficiency of the plasmonic and FRET‐enabled DSSC with ZnO/N719/Au@C‐dots as the photoanode, I2/I− as the electrolyte and multiwalled carbon nanotubes as the counter electrode is 4.1 %, greater by 29 % compared to a traditional ZnO/N719 cell.
Coordinate‐Targeted and Coordinate‐Stochastic Super‐Resolution Microscopy with the Reversibly Switchable Fluorescent Protein Dreiklang
Authors: Jensen Nickels A. , Danzl Johann G. , Willig Katrin I. , Lavoie‐Cardinal Flavie , Brakemann Tanja , Hell Stefan W. , Jakobs Stefan
Published: February 2014

Diffraction‐unlimited far‐field super‐resolution fluorescence (nanoscopy) methods typically rely on transiently transferring fluorophores between two states, whereby this transfer is usually laid out as a switch. However, depending on whether this is induced in a spatially controlled manner using a pattern of light (coordinate‐targeted) or stochastically on a single‐molecule basis, specific requirements on the fluorophores are imposed. Therefore, the fluorophores are usually utilized just for one class of methods only. In this study we demonstrate that the reversibly switchable fluorescent protein Dreiklang enables live‐cell recordings in both spatially controlled and stochastic modes. We show that the Dreiklang chromophore entails three different light‐induced switching mechanisms, namely a reversible photochemical one, off‐switching by stimulated emission, and a reversible transfer to a long‐lived dark state from the S1 state, all of which can be utilized to overcome the diffraction barrier. We also find that for the single‐molecule‐based stochastic GSDIM approach (ground‐state depletion followed by individual molecule return), Dreiklang provides a larger number of on–off localization events as compared to its progenitor Citrine. Altogether, Dreiklang is a versatile probe for essentially all popular forms of live‐cell fluorescence nanoscopy.
Contrasting responses of non‐small cell lung cancer to antiangiogenic therapies depend on histological subtype
Authors: Larrayoz Marta , Pio Ruben , Pajares María J , Zudaire Isabel , Ajona Daniel , Casanovas Oriol , Montuenga Luis M , Agorreta Jackeline
Published: February 2014

The vascular endothelial growth factor (VEGF) pathway is a clinically validated antiangiogenic target for non‐small cell lung cancer (NSCLC). However, some contradictory results have been reported on the biological effects of antiangiogenic drugs. In order to evaluate the efficacy of these drugs in NSCLC histological subtypes, we analyzed the anticancer effect of two anti‐VEGFR2 therapies (sunitinib and DC101) in chemically induced mouse models and tumorgrafts of lung adenocarcinoma (ADC) and squamous cell carcinoma (SCC). Antiangiogenic treatments induced vascular trimming in both histological subtypes. In ADC tumors, vascular trimming was accompanied by tumor stabilization. In contrast, in SCC tumors, antiangiogenic therapy was associated with disease progression and induction of tumor proliferation. Moreover, in SCC, anti‐VEGFR2 therapies increased the expression of stem cell markers such as aldehyde dehydrogenase 1A1, CD133, and CD15, independently of intratumoral hypoxia. In vitro studies with ADC cell lines revealed that antiangiogenic treatments reduced pAKT and pERK signaling and inhibited proliferation, while in SCC‐derived cell lines the same treatments increased pAKT and pERK, and induced survival. In conclusion, this study evaluates for the first time the effect of antiangiogenic drugs in lung SCC murine models in vivo and sheds light on the contradictory results of antiangiogenic therapies in NSCLC.
Review of Methods for Improving the Cyclic Stability of Li–Air Batteries by Controlling Cathode Reactions
Authors: Zhao Ning , Li Chilin , Guo Xiangxin
Published: February 2014

The rechargeable Li–air battery (as well as the Li–O2 battery) is a promising candidate for energy storage applications, especially in application of electrical vehicles. However, many technical obstacles such as the limited cyclic stability, low electrical energy efficiency, and poor rate capability must be solved prior to its practical use. In this review, we focus on methods for extension of the cycle lifetime by controlling the key operation parameters. The important influence of working parameters on the cycle operation and the underlying mechanism related to cathode reactions are addressed. It is demonstrated that battery technology in combination with knowledge of the cathode material characteristics is essential for improvement of battery performance. Prospective utilization of battery technology for overcoming other problems of Li–air batteries is also discussed.
Effect of slurry dilution, structural carbohydrates, and exogenous archaea supply on in vitro anaerobe fermentation and methanogens population of swine slurry
Authors: Morazán Henris , Seradj Ahmad Reza , Alvarez‐Rodriguez Javier , Abecia Leticia , Babot Daniel , Yañez‐Ruiz David R. , Balcells Joaquim
Published: February 2014

Artificial slurry (4% dry matter) was prepared using fresh feces and urine obtained from four pregnant sows fed with commercial diet. Freeze‐dried dairy cattle feces were used (external archaea) as co‐inoculum (Co‐i) and structural carbohydrates (CHO: apple pulp; sugar beet pulp; and wheat straw) as substrates. Bottles were incubated (39 ± 1°C for 56 days), and the gas production was measured (mbar) and converted to the volume. A sample of produced gas was taken and analyzed for methane concentration using a gas chromatography. Bottles were opened at days 0, 25, and 56 to determine total bacteria, total, and hydrogenotrophic methanogens archaea (HMA) concentrations using quantitative polymerase chain reaction and population biodiversity using denaturing gradient gel electrophoresis (DGGE). Incubation time reduced the titers of total bacteria and archaea (P < 0.01) but did not modify HMA population. Doses of Co‐i showed a positive correlation with HMA titers, although interacted with an incubation period (P < 0.001); at 5% Co‐inoculation, total bacteria decreased significantly (0–25 days) but remained steady until day 56 (P > 0.05), whereas at 10% Co inoculation, titers decreased constantly. Most of the archaeal DGGE bands were observed in all samples, suggesting a common microbial population origin but Co‐i supply altered the DGGE structure of archaea populations. © 2014 American Institute of Chemical Engineers Environ Prog, 34: 54–64, 2015
Eolian Deposition and Soil Fertility in a Prehistoric Agricultural Complex in Central Arizona, USA
Authors: Nakase Dana K. , Hartshorn Anthony S. , Spielmann Katherine A. , Hall Sharon J.
Published: February 2014

Prehistoric farmers in arid and semiarid ecosystems commonly used rock alignments to concentrate water and sediments on their fields. Previous research has emphasized the importance of runoff from organic matter‐rich uplands as a mechanism for soil nutrient replenishment. However, eolian inputs to these dryland ecosystems might also contribute substantially to mineral‐derived nutrient pools. We explored the relative importance of eolian deposition, prehistoric agriculture, and the presence of rock alignments on soil properties in a semiarid grassland in Arizona. Subsurface soils behind natural rock alignments are finer in texture than soils unbound by rock alignments, while subsurface soils behind agricultural rock alignments coarsen relative to unbound soils. Neither rock alignments nor estimated crop yields had detectable effects on mineral‐derived nutrient pools. In contrast, eolian deposition is an important source of soil mass and nutrients to modern soils. While dust deposition likely reduced soil heterogeneity across this landscape, it could have also contributed to the sustainability of prehistoric agriculture.
Impact of the introduction of rituximab in first‐line follicular lymphoma: a retrospective study of 247 unselected patients referred to a single institution with a long‐term follow‐up
Authors: Nicolas‐Virelizier Emmanuelle , Ségura‐Ferlay Céline , Ghesquières Herve , Chassagne‐Clément Catherine , Gargi Thérèse , Biron Pierre , Belhabri Amine , Rey Philippe , Faurie Pierre , Chabaud Sylvie , Sebban Catherine
Published: February 2014

Rituximab was approved in France in 2004, following randomized trials that demonstrated efficacy in newly diagnosed high tumour burden follicular lymphoma (FL). This retrospective study compared the management and outcome of FL in unselected patients treated in a single institution before and after rituximab approval. Two hundred and forty‐seven adult patients were referred with first‐line FL between 1996 and 2010 and are included in this study. The 103 pre‐rituximab patients comprising cohort 1 were diagnosed between January 1996 and December 2003; cohort 2 includes the 144 patients diagnosed after the approval of rituximab between January 2004 and December 2010. Baseline clinical and biological data, type of therapy, treatment response, progression‐free survival (PFS) and overall survival (OS) rates were compared. There were no statistically significant differences between the two cohorts with respect to baseline clinical and disease characteristics, including FL International Prognostic Index score. The major difference between the two cohorts is the use of rituximab in first line. Seventy‐one per cent of patients in cohort 2 received rituximab (19% alone, 52% with chemotherapy) versus 10% in cohort 1 (2% alone, 8% with chemotherapy;p < 0.0001). The objective response rate (ORR) was significantly higher for cohort 2 (ORR84% compared with 72% for cohort 1;p = 0.03). The PFS and OS rates were also significantly better: 3‐yearPFS72% [95% confidence interval (CI) 64–80%] versus 55% (95% CI 45–64%),p = 0.0039 and 3‐yearOS98% (95% CI 94–99%) versus 83% (95% CI 74–90%),p = 0.0007. Effect of period of study is significant when using multivariate analysis on PFS and OS and lactate dehydrogenase level (PFS and OS) and age (OS). These data from everyday practice confirm the benefit for patients with FL treated in the last decade through availability of rituximab in first line used alone or in association with various chemotherapy regimens. Copyright © 2014 John Wiley & Sons, Ltd.
ADOPTION POLICY AND EVIDENCE‐BASED DOMESTIC ADOPTION PRACTICE: A COMPARISON OF ROMANIA, UKRAINE, INDIA, GUATEMALA, AND ETHIOPIA
Authors: Groza Victor , Bunkers Kelley M.
Published: February 2014

The United Nations Convention on the Rights of the Child (1989), The Hague Convention on the Protection of Children and Co‐operation in Respect of Intercountry Adoption (The Hague Permanent Bureau, 1993), and the Guidelines for the Alternative Care of Children (2009) have provided a comprehensive, rights‐based framework and guidance for developing domestic adoption and alternative, family based care programs. Domestic adoption is a critical component of any child‐protection system and a core part of the range of alternative care options that the United Nations and other international organizations recommend be developed, resourced, and made accessible to children without parental care. This article uses data collected from adoptive parents’ postadoption and governmental data in Romania, Ukraine, India, Guatemala, and Ethiopia to focus on domestic adoption in each of these countries. The article highlights both promising practices in domestic adoption as well as policies and practices that require additional research.
Explicit proton transfer in classical molecular dynamics simulations
Authors: Wolf Maarten G. , Groenhof Gerrit
Published: February 2014

We present Hydrogen Dynamics (HYDYN), a method that allows explicit proton transfer in classical force field molecular dynamics simulations at thermodynamic equilibrium. HYDYN reproduces the characteristic properties of the excess proton in water, from the special pair dance, to the continuous fluctuation between the limiting Eigen and Zundel complexes, and the water reorientation beyond the first solvation layer. Advantages of HYDYN with respect to existing methods are computational efficiency, microscopic reversibility, and easy parameterization for any force field. © 2014 Wiley Periodicals, Inc.
Integrating open‐source software applications to build molecular dynamics systems
Authors: Allen Bruce M. , Predecki Paul K. , Kumosa Maciej
Published: February 2014

Three open‐source applications, NanoEngineer‐1, packmol, and mis2lmp are integrated using an open‐source file format to quickly create molecular dynamics (MD) cells for simulation. The three software applications collectively make up the open‐source software (OSS) suite known as MD Studio (MDS). The software is validated through software engineering practices and is verified through simulation of the diglycidyl ether of bisphenol‐a and isophorone diamine (DGEBA/IPD) system. Multiple simulations are run using the MDS software to create MD cells, and the data generated are used to calculate density, bulk modulus, and glass transition temperature of the DGEBA/IPD system. Simulation results compare well with published experimental and numerical results. The MDS software prototype confirms that OSS applications can be analyzed against real‐world research requirements and integrated to create a new capability. © 2014 Wiley Periodicals, Inc.
Effects of predictability and competition on group and individual choice in a free‐ranging foraging environment
Authors: Tan Lavinia , Sosa Frank , Talbot Eric , Berg Donald , Eversz Dawniris , Hackenberg Timothy D.
Published: February 2014

The present study examined the social foraging of rats in an open arena. The relative quantity of food varied across two food sources, or “patches.” Five food quantity ratios (1:1, 1:2, 1:8, 8:1, 2:1) were presented in a series of 30‐min sessions. Ratios varied randomly across 6‐min components within sessions (Phase 1), or in a consistent order across sessions (Phase 2). Group and individual preferences were well described by the ideal free distribution and the generalized matching law, respectively, with evidence of undermatching at both group and individual levels. Sensitivity of individual and collective behavior to the relative quantities of food was higher in Phase 2 than in Phase 1. Competitiveness rankings, assessed before and after experimental sessions by delivering food in rapid succession from a single feeder, was positively related to sensitivity values in Phase 1, but less consistently so in Phase 2. This study illustrates a promising experimental method for investigating foraging in a social context.
Cellular basis of differential limb growth in postnatal gray short‐tailed opossums (Monodelphis domestica)
Authors: Beiriger Anastasia , Sears Karen E.
Published: February 2014

While growth has been studied extensively in invertebrates, the mechanisms by which it is controlled in vertebrates, particularly in mammals, remain poorly understood. In this study, we investigate the cellular basis of differential limb growth in postnatal Monodelphis domestica, the gray short‐tailed opossum, to gain insights into the mechanisms regulating mammalian growth. Opossums are an ideal model for the study of growth because they are born with relatively large, well‐developed forelimbs and small hind limbs that must “catch up” to the forelimb before the animal reaches adulthood. Postnatal Days 1–17 were identified as a key period of growth for the hind limbs, during which they undergo accelerated development and nearly quadruple in length. Histology performed on fore‐ and hind limbs from this period indicates a higher rate of cellular differentiation in the long bones of the hind limbs. Immunohistochemical assays indicate that cellular proliferation is also occurring at a significantly greater rate in the long bones of the hind limb at 6 days after birth. Taken together, these results suggest that a faster rate of cellular proliferation and differentiation in the long bones of the hind limb relative to those of the forelimb generates a period of accelerated growth through which the adult limb phenotype of M. domestica is achieved. Assays for gene expression suggest that the molecular basis of this differential growth differs from that previously identified for differential pre‐natal growth in opossum fore‐ and hind limbs. J. Exp. Zool. (Mol. Dev. Evol.) 322B: 221–229, 2014. © 2014 Wiley Periodicals, Inc.
Stakeholder Network Integrated Analysis: The Specific Case of Rural Tourism in the Portuguese Peneda‐Gerês National Park
Authors: Nogueira Sónia , Pinho José Carlos
Published: February 2014

This study addresses the structure, nature and composition of stakeholder networks related to rural tourism in a Portuguese National Park (Peneda‐Gerês National Park). In particular, it examines their interactions along the following dimensions: marketing information (marketing exchanges such as flyers, tourism information and information on specific events), administrative resources (logistic and technical support), human resources (allocation of human resources), training (training of local stakeholders in the area of promotion) and financial resources (financial support). In terms of methodology, it uses both qualitative and quantitative techniques.

The analysis of the type and nature of interactions among different stakeholders within a specific rural tourism destination is the main focus of this study. Among these, the marketing information network shows both a high number of connections and high centrality indices, which may indicate that there is a significant share of information about common projects, products and services among stakeholders. In contrast, the training network evidenced the opposite behavior pattern. The study also contributes to a better understanding of how different local stakeholders are positioned in a complex structure of interactions that are critical in providing useful directions to maximize potential opportunities that may contribute to promote rural tourism and local development efficiently. Several limitations and implications are offered in the final section. Copyright © 2014 John Wiley & Sons, Ltd.
Minimally invasive functional approach for cholesteatoma surgery
Authors: Hanna Bassem M. , Kivekäs Ilkka , Wu Yi‐Hsuan , Guo Lee J. , Lin Huang , Guidi Jessica , Poe Dennis
Published: February 2014

Objectives/Hypothesis

Report the efficacy of a functional minimally invasive approach for cholesteatoma surgery.

Study Design

Retrospective review of surgical cases performed between 1996 and 2008.

Methods

One hundred sixty‐nine patient charts were reviewed in which ears with primary cholesteatomas that extended beyond the mesotympanum were operated on with a plan for canal wall up (CWU) mastoidectomy. The surgical approach consisted of progressive exposure from transcanal to postauricular tympanoplasty to CWU mastoidectomy, as needed, to identify and lyse the fibrous attachments that bind the capsule to the surrounding mucosa. Endoscopic guidance was employed as appropriate to minimize exposure needs. Any planned second‐stage operations were attempted with a transcanal approach if appropriate and with endoscopic assistance.

Results

One hundred eighty‐four ears of 169 patients were included. The median age was 32 years (range, 1–79 years). The mean follow‐up was 3.2 years (range, 1–11 years). Eighty‐three (45%) were planned for a second‐look operation, and three (2%) required unplanned second operations. The overall recurrence rate was 24/184 (13%), and the unexpected residual rate was 5/184 (3%). The residual rate with endoscopy (5/119, 4%,) or without endoscopy (1/65, 2%), were not significantly different. Hearing results in 156 ears improved significantly, from a preoperative pure‐tone average (PTA) of 41 dB to a postoperative PTA average of 29 dB (P < .0001).

Conclusions

A functional minimally invasive approach to cholesteatoma surgery provided equivalent residual rates but higher recurrence rates compared to published canal wall down mastoidectomy. Endoscopic techniques were helpful in providing adequate views while minimizing exposure.

Level of Evidence

4 Laryngoscope, 124:2386–2392, 2014
Matrices of completely Ramsey sets with infinitely many rows
Authors: Tsarpalias Athanasios
Published: February 2014

The main result of the present article is the following: Let N be an infinite subset of , , and let be a matrix with infinitely many rows of completely Ramsey subsets of such that for every n, . Then there exist , a sequence of nonempty finite subsets of N, and an infinite subset T of such that for every infinite subset I of . We also give an application of this result to partitions of an uncountable analytic subset of a Polish space X into sets belonging to the σ‐algebra generated by the analytic subsets of X.
High frequency of exon 15 deletion in the FANCA gene in Tunisian patients affected with Fanconi anemia disease: implication for diagnosis
Authors: Amouri Ahlem , Talmoudi Faten , Messaoud Olfa , d'Enghien Catherine D. , Rekaya Mariem B. , Allegui Ines , Azaiez Héla , Kefi Rym , Abdelhak Ahlem , Meseddi Sondes H. , Torjemane Lamia , Ouederni Monia , Mellouli Fethi , Abid Héla B. , Aissaoui Lamia , Bejaoui Mohamed , Othmen Tarek B. , Lyonnet Dominique S. , Soulier Jean , Hachicha Mongia , Dellagi Koussay , Abdelhak Sonia ,   Tunisian Fanconi Anemia Study Group
Published: February 2014

Tunisian population is characterized by its heterogeneous ethnic background and high rate of consanguinity. In consequence, there is an increase in the frequency of recessive genetic disorders including Fanconi anemia (FA). The aim of this study was to confirm the existence of a founder haplotype among FA Tunisian patients and to identify the associated mutation in order to develop a simple tool for FA diagnosis. Seventy‐four unrelated families with a total of 95 FA patients were investigated. All available family members were genotyped with four microsatellite markers flanking FANCA gene. Haplotype analysis and homozygosity mapping assigned 83 patients belonging to 62 families to the FA‐A group. A common haplotype was shared by 42 patients from 26 families at a homozygous state while five patients from five families were heterozygous. Among them, 85% were from southern Tunisia suggesting a founder effect. Using multiplex ligation‐dependent probe amplification (MLPA) technique, we have also demonstrated that this haplotype is associated with a total deletion of exon 15 in FANCA gene. Identification of a founder mutation allowed genetic counseling in relatives of these families, better bone marrow graft donor selection and prenatal diagnosis. This mutation should be investigated in priority for patients originating from North Africa and Middle East.
Bunte Aspekte: Häm und seine Abbauprodukte
Authors: Ohlenschläger Oliver , Schiller Alexander , Jahns Franziska , Heinemann Stefan H.
Published: February 2014

Ein tödlicher Hirnschlag oder ein harmloser blauer Fleck unter der Haut — in beiden Fällen sind Häm‐Moleküle und deren Spaltprodukte beteiligt. Die regulatorischen Funktionen des Häms und seiner Abbauprodukte im Organismus aufzudecken, ist das Ziel neuer Forschungen.
Chrom‐Autorisierung unter Reach für kleine und mittlere Betriebe
Authors: König Uwe
Published: February 2014

Wie können Unternehmen mit der europäischen Chemikalienregelung umgehen, damit ihre Fertigung in den nächsten Jahren gesichert ist? Eine Lösung ist, die Kommunikation und Kooperation entlang der Lieferkette zu stärken, wie dies bei der Verwendung von Chrom(VI)‐Verbindungen angestrebt wird.
Erfolg für Oberstufenschüler
Authors: Tausch Michael W.
Published: February 2014

Schulen aus Deutschland beteiligen sich am internationalen Chemiewettbewerb “Australian National Chemistry Quiz”.
Nucleation effects of sodium and ammonium salts of 2,2′‐methylene‐bis‐(4,6‐di‐t‐butylphenylene)phosphate in isotactic polypropylene
Authors: Long Lijuan , He Wentao , Zhang Minmin , Zhang Kai , Qin Shuhao , Yu Jie
Published: February 2014

The nucleation ability of isotactic poly(propylene) (iPP) to ammonium 2,2′‐methylene‐bis‐(4,6‐di‐t‐butylphenylene) phosphate (An) was investigated in the present work comparing with sodium 2,2′‐methylene‐bis‐(4,6‐di‐t‐butylphenylene) phosphate (NA‐11). Scanning electron microscope (SEM) revealed the crystalline morphology of both An and NA‐11 with planar surface characteristics. The observation of the fracture surface of nucleation iPP samples by SEM showed An particles were dispersed uniformly in polymer and had a better compatibility with iPP matrix than NA‐11 particles. Differential scanning calorimeter (DSC) showed that the melting temperature of An was 262°C significantly lower than that measured from NA‐11 group (above 400°C). Crystallization behaviors of iPP/NA‐11 and iPP/An were also investigated by DSC analysis, respectively. The results showed the crystallization peak temperature and the crystallinity of iPP/An were almost near to that of iPP/NA‐11. Furthermore, mechanical and optical properties of iPP were strongly improved in the presences of An and NA‐11. The flexural strength of iPP was elevated 34 and 35% and the haze value was reduced from 40.4 to 15.1 and 14.9% by the addition of 0.15 wt% NA‐11 and An, respectively. These results demonstrate that the nucleating agent of An described here is a good nucleating agent for the crystallization of iPP as well as NA‐11. POLYM. ENG. SCI., 55: 22–28, 2015. © 2014 Society of Plastics Engineers
Mechanical and thermal properties of toughened PA6/HDPE/SEBS‐g‐MA/Clay nanocomposite
Authors: Attari Marzieh , Arefazar Ahmad , Bakhshandeh Gholamreza
Published: February 2014

Preparation and morphology of Polyamide 6 (PA6)/high density polyethylene (HDPE)/Styrene/Ethylene–Butylene/Styrene grafted with maleic anhydride (SEBS‐g‐MA)/Modified clay nanocomposites were studied. Mixing was performed using melting process in an extruder co‐rotating twin screw. After etching the materials with boiling toluene and THF at room temperature, the morphology of sample checked by scanning electron microscopy (SEM) analyses. X‐ray diffraction (XRD) used for evaluation of the effects of organo‐clay addition in the structure of nanocomposites. XRD traces showed that the characteristic (001) peak of the nanocomposites shifted to the lower degree region. XRD and SEM results showed more uniformly distribution and dispersion of HDPE in the PA6 matrix. Better sample morphology obtained, regarding less distance, and more uniformity between nanoparticles. The mechanical properties like tensile strength, impact strength, hardness and thermal properties of these toughened nanocomposites are discussed in terms of the nanoclay, SEBS‐g‐MA contents and morphology. Adding nanoclay improved hardness of nanocomposites product but reduced toughness and thermal properties. Meanwhile the presence of SEBS‐g‐MA as a compatibilizer improved toughness, thermal properties, hardness property, and the balance properties are achieved. POLYM. ENG. SCI., 55:29–33, 2015. © 2014 Society of Plastics Engineers