bluuebunny/crossref_metadata_2025 huggingface dataset:
Northwestern Argentina: A Center of Genetic Diversity of Lemon Verbena (Aloysia citriodoraPaláu, Verbenaceae)
Authors: Di Leo Lira Paola , van Baren Catalina M. , López Simon , Molina Ana , Heit Cecilia , Viturro Carmen , de Lampasona Marina P. , Catalán Cesar A. , Bandoni Arnaldo
Published: February 2013

The aerial parts of lemon verbena (Aloysia citriodora Paláu) are worldwide used due to their medicinal and aromatic properties. The essential‐oil and acteoside contents have been proposed as the main quality markers for their pharmacological and organoleptic features. The northwestern region of Argentina has been repeatedly proposed as the place of origin for this species. For this reason, the essential‐oil yields and chemical compositions of leaves of 25 populations of lemon verbena from both wild collections and experimental crops from this region were studied. Plants from six different collections were subsequently grown on the same experimental parcel located at Cerrillos, Salta province, during more than seven years. In addition, the acteoside contents determined in all the samples collected in 2010 showed significant variations (from 0.5 to 4.0%). Large differences were observed in the essential‐oil composition and yields, which ranged from 0.4 to 2.1% (v/w). Nevertheless, most of the samples complied with the European Pharmacopoeia specifications. A remarkable chemical diversity with at least four clearly defined chemotypes was detected in this region. Therefore, it would be urgent to encourage actions to protect these genotypes of lemon verbena in the northwestern Argentina.
Chemical Composition and Antimicrobial and Allelopathic Activity of Tunisian Conyza sumatrensis (Retz.) E.Walker Essential Oils
Authors: Mabrouk Samia , Salah Karima Bel Hadj , Elaissi Ameur , Jlaiel Lobna , Jannet Hichem Ben , Aouni Mahjoub , Harzallah‐Skhiri Fethia
Published: February 2013

Conyza sumatrensis (Retz.) E.Walker (Asteraceae) is a spontaneous annual herb, fairly widespread throughout Tunisia, which has rarely been studied or valued in any sector. Essential oils were obtained by hydrodistillation of different parts (flower heads, leaves, stems, and roots) of C. sumatrensis plants, which were collected in autumn (November 2007) at the flowering stage in the area of Monastir, Tunisia. In total, 98 compounds, representing 88.1–99.3% of the oil composition, were identified by GC‐FID and GC/MS analyses. The root essential oil was distinguished by its high content in acetylenes (matricaria ester, 4; 74.3%), while those from flower heads and leaves were dominated by oxygenated sesquiterpenes (61.1 and 50.3%, resp.). The oils of C. sumatrensis from Tunisia belonged to a matricaria ester/caryophyllene oxide chemotype. All the oils were evaluated for antibacterial, antifungal, and allelopathic activities. The results indicate that the leaf oil exhibited significant in vitro antibacterial activity against Enterococcus faecalis, Staphylococcus aureus, and Proteus mirabilis and that the C. sumatrensis oils isolated from the aerial parts presented high mycelia‐growth inhibition of Candida albicans and the filamentous fungi tested. Moreover, the essential oils of the different plant parts inhibited the shoot and root growth of Raphanus sativus (radish) seedlings. Indeed, the inhibition of the hypocotyl growth varied from 28.6 to 90.1% and that of the radicle from 42.3 to 96.2%.
Chemical Diversity among the Essential Oils of Wild Populations of Stachys lavandulifoliaVahl (Lamiaceae) from Iran
Authors: Aghaei Yaqub , Hossein Mirjalili Mohammad , Nazeri Vahideh
Published: February 2013

The variation of the essential‐oil composition among ten wild populations of Stachys lavandulifolia Vahl (Lamiaceae), collected from different geographical regions of Iran, was assessed by GC‐FID and GC/MS analyses, and their intraspecific chemical variability was determined. Altogether, 49 compounds were identified in the oils, and a relatively high variation in their contents was found. The major compounds of the essential oils were myrcene (0.0–26.2%), limonene (0.0–24.5%), germacrene D (4.2–19.3%), bicyclogermacrene (1.6–18.0%), δ‐cadinene (6.5–16.0%), pulegone (0.0–15.1%), (Z)‐hex‐3‐enyl tiglate (0.0–15.1%), (E)‐caryophyllene (0.0–12.9), α‐zingiberene (0.2–12.2%), and spathulenol (1.6–11.1%). For the determination of the chemotypes and the chemical variability, the essential‐oil components were subjected to cluster analysis (CA). The five different chemotypes characterized were Chemotype I (germacrene D/bicyclogermacrene), Chemotype II (germacrene D/spathulenol), Chemotype III (limonene/δ‐cadinene), Chemotype IV (pulegone), and Chemotype V (α‐zingiberene). The high chemical variation among the populations according to their geographical and bioclimatic distribution imposes that conservation strategies of populations should be made appropriately, taking into account these factors. The in situ and ex situ conservation strategies should concern all populations representing the different chemotypes.
Hydrodeoxygenation of Phenol and Derivatives over an Ionic Liquid‐Like Copolymer Stabilized Nanocatalyst in Aqueous Media
Authors: Chen Jinzhu , Huang Jing , Chen Limin , Ma Longlong , Wang Tiejun , Zakai Uzma I.
Published: February 2013

Using phenolic bio‐oil as feedstock for sustainable production of alkane fuels is of great significance. Here, the hydrodeoxygenation of phenol and its derivatives has been systematically investigated in aqueous media with a dual‐functional catalyst system consisting of water‐soluble, ionic liquid‐like copolymer A‐stabilized nanocatalysts and the mineral acid H3PO4. The developed Ru/A‐H3PO4 catalyst system achieved a complete phenol conversion with cyclohexane selectivity higher than 99 %, making it by far one of the most efficient systems for phenol hydrodeoxygenation. Mercury poisoning experiments revealed that the in situ generated Ru nanoparticles are true a heterogeneous catalyst for hydrogenation. The catalytic activity of metal site for phenol hydrodeoxygenation to cyclohexane decreased with the order of Ru>Rh>Pt≫Pd. Our findings also demonstrated the delicate balance between activity and stability of ionic liquid‐like copolymer‐stabilized nanocatalysts. The research highlights an efficient catalyst system of transforming phenols into alkanes.
New Synthesis of A‐Ring Aromatic Strigolactone Analogues and Their Evaluation as Plant Hormones in Pea (Pisum sativum)
Authors: Chen Victor X. , Boyer François‐Didier , Rameau Catherine , Pillot Jean‐Paul , Vors Jean‐Pierre , Beau Jean‐Marie
Published: February 2013

A new general access to A‐ring aromatic strigolactones, a new class of plant hormones, has been developed. The key transformations include in sequence ring‐closing metathesis, enzymatic kinetic resolution and a radical cyclization with atom transfer to install the tricyclic ABC‐ring system. The activity as plant hormones for the inhibition of shoot branching in pea of various analogues synthesized by this strategy is reported.
Group IV Organometallic Compounds Based on Dianionic “Pincer” Ligands: Synthesis, Characterization, and Catalytic Activity in Intramolecular Hydroamination Reactions
Authors: Luconi Lapo , Rossin Andrea , Motta Alessandro , Tuci Giulia , Giambastiani Giuliano
Published: February 2013

Neutral ZrIV and HfIV diamido complexes stabilized by unsymmetrical dianionic N,C,N′ pincer ligands have been prepared through the simplest and convenient direct metal‐induced CarylH bond activation. Simple ligand modification has contributed to highlight the non‐innocent role played by the donor atom set in the control of the cyclometallation kinetics. The as‐prepared bis‐amido catalysts were found to be good candidates for the intramolecular hydroamination/cyclization of primary aminoalkenes. The ability of these compounds to promote such a catalytic transformation efficiently (by providing, in some cases, fast and complete substrate conversion at room temperature) constitutes a remarkable step forward toward catalytic systems that can operate at relatively low catalyst loading and under milder reaction conditions. Kinetic studies and substrate‐scope investigations, in conjunction with preliminary DFT calculations on the real systems, were used to elucidate the effects of the substrate substitution on the catalyst performance and to support the most reliable mechanistic path operative in the hydroamination reaction.
Solid‐State Structural Transformations and Photoreactivity of 1D‐Ladder Coordination Polymers of PbII
Authors: Kole Goutam Kumar , Peedikakkal Abdul Malik Puthan , Toh Belinda Mei Fang , Vittal Jagadese J.
Published: February 2013

An attempt has been made to design double‐stranded ladder‐like coordination polymers (CPs) of hemidirected PbII. Four CPs, [Pb(μ‐bpe)(O2C‐C6H5)2]⋅2H2O (1), [Pb2(μ‐bpe)2(μ‐O2C‐C6H5)2(O2C‐C6H5)2] (2), [Pb2(μ‐bpe)2(μ‐O2C‐p‐Tol)2(O2C‐p‐Tol)2]⋅ 1.5 H2O (3) and [Pb2(μ‐bpe)2(μ‐O2C‐m‐Tol)2(O2C‐m‐Tol)2] (4) (bpe=1,2‐bis(4′‐pyridyl)ethylene), have been synthesised and investigated for their solid‐state photoreactivity. CPs 2–4, having a parallel orientation of bpe molecules in their ladder structures and being bridged by carboxylates, were found to be photoreactive, whereas CP 1 is a linear one‐dimensional (1D) CP with guest water molecules aggregating to form a hydrogen‐bonded 1D structure. The linear strands of 1 were found to pair up upon eliminating lattice water molecules by heating, which led to the solid‐state structural transformation of photostable linear 1D CP 1 into photoreactive ladder CP 2. In the construction of the double‐stranded ladder‐like structures, the parallel alignment of CC bonds in 2–4 is dictated by the chelating and μ2‐η2:η1 bridging modes of the benzoate and toluate ligands. The role of solvents in the formation of such double‐stranded ladder‐like structures has also been investigated. A single‐crystal‐to‐single‐crystal transformation occurred when 4 was irradiated under UV light to form [Pb2(rctt‐tpcb)(μ‐O2C‐m‐Tol)2(O2C‐m‐Tol)2] (5).
Assembly of Framework‐Isomeric 4 d–4 f Heterometallic Metal–Organic Frameworks with Neutral/Anionic Micropores and Guest‐Tuned Luminescence Properties
Authors: Ma Jing‐xin , Huang Xiao‐feng , Song Xue‐qin , Liu Wei‐sheng
Published: February 2013

Framework‐isomeric three‐dimensional (3D) Cd–Ln heterometallic metal–organic frameworks (HMOFs), {[Ln2(ODA)6Cd3(H2O)6]⋅6 H2O}n (Ln=Gd (1 a) and Tb (1 b), ODA=oxydiacetic acid) and {[Cd(H2O)6]⋅[Ln2(ODA)6Cd2]⋅H2O}n (Ln=Gd (2 a), Tb (2 b)), with neutral and anionic pores, respectively, were designed based on a lanthanide metalloligand strategy and synthesized by using a stepwise assembly and a hydrothermal method. Luminescence studies revealed that 1 b and 2 b can act as luminescent metal–organic frameworks and their light‐emitting properties can be modulated by small guest molecules and the manganese counterion, respectively.
Glycosylated Nanoscale Surfaces: Preparation and Applications in Medicine and Molecular Biology
Authors: Kennedy David C. , Grünstein Dan , Lai Chian‐Hui , Seeberger Peter H.
Published: February 2013

Carbohydrates on cell surfaces are critical components of the extracellular landscape and contribute to cell signalling, motility, adhesion and recognition. Multivalent effects are essential to these interactions that are inherently weak. Carbohydrate‐functionalised surfaces meet an important need for studying the multivalent interactions between carbohydrates and other biomolecules. Innovations in nanomaterials are revolutionising how these carbohydrate interfaces are studied and underscore their importance in the cosmos of biochemical interactions.
Laser‐Based Generation of Nanocomposites without Matrix‐Coupling Agents for Bioactive Medical Devices
Authors: Schwenke Andreas , Wagener Philipp , Weiß André , Klimenta Klaus , Wiegel Heinz , Sajti Laszlo , Barcikowski Stephan
Published: February 2013

Zur Ausschöpfung des Potenzials funktionaler Nanomaterialen bedarf es neuartiger Produktionsverfahren, die die Dispersion der Nanopartikel entlang der Prozesskette sicherstellen. Am Beispiel von Medizinprodukten mit antibakteriellem Schutz vor Biofilmbildung auf Basis von Silbernanopartikeln werden die Volumenintegration in Kunststoffe und die Nanopartikelsynthese durch Laserabtrag in Flüssigkeiten vorgestellt. Die antibakterielle Wirksamkeit der Nanokomposite und Verarbeitbarkeit zu Prototypen werden gezeigt.
Development of a Reactor Setup for Continuous Dehydration of Carbohydrates
Authors: Weisgerber Laurent , Palkovits Stefan , Palkovits Regina
Published: February 2013

The shortage of fossil energy carriers demands the use of renewable and sustainable energy resources. Biomass has the potential to fulfill these needs. The chemical transformation of cellulose, being a main part of plant biomass, allows the production of a widespread variety of chemicals. One especially promising candidate as platform molecule is 5‐hydroxymethylfurfural (5‐HMF). Until now 5‐HMF was predominantly produced in batch reactions from fructose as substrate within high boiling solvents. A working setup for producing 5‐HMF continuously out of fructose or in a coupled two‐step reaction, out of glucose, in low boiling solvents is introduced.
Evaluation of Bioavailability and Partitioning of Aluminum in Sediment Samples of Different Ecosystems by Modified Sequential Extraction Methods
Authors: Khan Sumaira , Kazi Tasneem G. , Arain Muhammad B. , Kolachi Nida F. , Baig Jameel A. , Afridi Hassan I. , Shah Abdul Q.
Published: February 2013

Sequential extraction procedures are widely used to characterize the different operational fractions with different potential toxicity of metals in environmental solid samples. The present work describes the application of different analytical approaches for sequential extraction of aluminum to evaluate its mobility, availability, and persistent chemical forms in sediment samples of different fresh water ecosystems (lake, canal, and river). The conventional BCR three‐stage sequential extraction procedure (C‐BCR) was modified at each stage, by applying ultrasonic device (U‐BCR), in order to shorten the required shaking time of 16 h for each three steps (excluding the hydrogen peroxide digestion in step 3, which was not performed with ultrasonic bath), could be completed in 40, 50, and 45 min, respectively. The aluminum in all extracts were determination by atomic absorption spectrometry using nitrous oxide – acetylene flame. The accuracy of results obtained from C‐BCR and proposed U‐BCR was verified with literature reported values of certified sediment sample (BCR 701). The overall recoveries of aluminum obtained by proposed U‐BCR were found in the range of 96.7–113% of those values obtained with C‐BCR for all fractions. Use of ultrasonic device, provided a large saving in extraction time relative to conventional shaking. It was observed that major part of Al in real sediment samples (80–83% of total Al) were bound to residual fraction. The acid soluble fraction of aluminum extracted by 0.11 mol/L CH3COOH has good correlation with aluminum content in corresponding water samples of each ecosystem.
Screening for distress in cancer patients
Authors: Grassi Luigi , Johansen Christoffer , Annunziata Maria Antonietta , Capovilla Eleonora , Costantini Anna , Gritti Paolo , Torta Riccardo , Bellani Marco ,   on behalf of the Italian Society of Psycho‐Oncology Distress Thermometer Study Group
Published: February 2013

BACKGROUND:

Routine screening for distress is internationally recommended as a necessary standard for good cancer care, given its high prevalence and negative consequences on quality of life. The objective of the current study was to contribute to the Italian validation of the Distress Thermometer (DT) to determine whether the single item DT compared favorably with referent criterion measures.

METHODS:

In total, 1108 outpatients with cancer were recruited from 38 representative oncology centers in Italy. Each participant completed the DT and a list of 34 possible cancer‐related problems (the Problem List), the Hospital Anxiety and Depression Scale (HADS), the 18‐item Brief Symptom Inventory (BSI‐18), and a short visual analog scale to determine the understandability of the tools.

RESULTS:

Receiver operating characteristic analysis revealed that DT cutoff scores ≥4 and ≥5 had optimal sensitivity and specificity relative to both HADS and BSI‐18 cutoff scores for general caseness and more severe psychological distress, respectively. Patients with DT scores ≥4 (cases) were more likely to be women; to have had psychological problems in the past; to report more stressful events in the last year; and to currently have more family, emotional, and physical problems related to cancer or cancer treatment. Patients indicated that the DT was easier to fill out and to understand than the HADS, but not the BSI‐18.

CONCLUSIONS:

The DT was identified as a simple and effective screening instrument for detecting distress in Italian cancer patients as a first step toward more properly referring those in need to psychosocial intervention. Cancer 2013. © 2013 American Cancer Society.
Phase 2 study of preoperative image‐guided intensity‐modulated radiation therapy to reduce wound and combined modality morbidities in lower extremity soft tissue sarcoma
Authors: O'Sullivan Brian , Griffin Anthony M. , Dickie Colleen I. , Sharpe Michael B. , Chung Peter W. M. , Catton Charles N. , Ferguson Peter C. , Wunder Jay S. , Deheshi Benjamin M. , White Lawrence M. , Kandel Rita A. , Jaffray David A. , Bell Robert S.
Published: February 2013

BACKGROUND:

This study sought to determine if preoperative image‐guided intensity‐modulated radiotherapy (IG‐IMRT) can reduce morbidity, including wound complications, by minimizing dose to uninvolved tissues in adults with lower extremity soft tissue sarcoma.

METHODS:

The primary endpoint was the development of an acute wound complication (WC). IG‐IMRT was used to conform volumes to avoid normal tissues (skin flaps for wound closure, bone, or other uninvolved soft tissues). From July 2005 to June 2009, 70 adults were enrolled; 59 were evaluable for the primary endpoint. Median tumor size was 9.5 cm; 55 tumors (93%) were high‐grade and 58 (98%) were deep to fascia.

RESULTS:

Eighteen (30.5%) patients developed WCs. This was not statistically significantly different from the result of the National Cancer Institute of Canada SR2 trial (P = .2); however, primary closure technique was possible more often (55 of 59 patients [93.2%] versus 50 of 70 patients [71.4%]; P = .002), and secondary operations for WCs were somewhat reduced (6 of 18 patients [33%] versus 13 of 30 patients [43%]; P = .55). Moderate edema, skin, subcutaneous, and joint toxicity was present in 6 (11.1%), 1 (1.9%), 5 (9.3%), and 3 (5.6%) patients, respectively, but there were no bone fractures. Four local recurrences (6.8%, none near the flaps) occurred with median follow‐up of 49 months.

CONCLUSIONS:

The 30.5% incidence of WCs was numerically lower than the 43% risk derived from the National Cancer Institute of Canada SR2 trial, but did not reach statistical significance. Preoperative IG‐IMRT significantly diminished the need for tissue transfer. RT chronic morbidities and the need for subsequent secondary operations for WCs were lowered, although not significantly, whereas good limb function was maintained. Cancer 2013. © 2013 American Cancer Society.
Synchronous cancers in patients with head and neck cancer
Authors: Jain Kunal S. , Sikora Andrew G. , Baxi Shrujal S. , Morris Luc G. T.
Published: February 2013

BACKGROUND:

Second primary malignancies (SPMs) are the leading cause of death in survivors of head and neck squamous cell carcinoma (HNSCC). Synchronous SPMs are of significant clinical interest because they potentially can be identified by screening procedures at the time of diagnosis of the index cancer. Recently, human papillomavirus (HPV) has emerged as a distinct risk factor for oropharyngeal head and neck squamous cell carcinoma (HNSCC), differing from classic tobacco/alcohol‐associated HNSCC, suggesting that there also may be distinct patterns of synchronous SPMs.

METHODS:

The authors performed a population‐based cohort study in 64,673 patients in the National Cancer Institute Surveillance, Epidemiology, and End Results registry (1979‐2008), defining risks of synchronous SPM in patients with HNSCC who were diagnosed before and after the emergence of prevalent HPV‐associated oropharyngeal HNSCC. Excess risk was calculated using standardized incidence ratios (SIR) and excess absolute risk per 100 patients.

RESULTS:

Among patients with HNSCC, the SIR of synchronous SPM was 5.0, corresponding to 2.62 excess cases per 100 patients. The site with the highest excess risk of a second cancer was the head and neck (SIR, 41.4), followed by the esophagus (SIR, 21.8), and lung (SIR, 7.4). The risk of synchronous SPM changed markedly over time for patients with oropharyngeal HNSCC. In the 1970s and 1980s, oropharyngeal cancers carried the highest risk of SPM. Risk began to dramatically decline in the 1990s; and currently, oropharyngeal cancers carry the lowest risk of synchronous SPM.

CONCLUSIONS:

The current data are consistent with the etiologic shift of oropharyngeal HNSCC, from a primarily tobacco‐associated malignancy associated with significant field cancerization of the upper aerodigestive mucosa, to a malignancy primarily caused by oncogenic human papillomavirus. Cancer 2013. © 2013 American Cancer Society.
Coregistered whole body magnetic resonance imaging‐positron emission tomography (MRI‐PET) versus PET‐computed tomography plus brain MRI in staging resectable lung cancer
Authors: Yi Chin A , Lee Kyung Soo , Lee Ho Yun , Kim Seonwoo , Kwon O Jung , Kim Hojoong , Choi Joon Young , Kim Byung‐Tae , Hwang Hye Sun , Shim Young Mog
Published: February 2013

BACKGROUND:

The objective of this study was to assess whether coregistered whole brain (WB) magnetic resonance imaging‐positron emission tomography (MRI‐PET) would increase the number of correctly upstaged patients compared with WB PET‐computed tomography (PET‐CT) plus dedicated brain MRI in patients with nonsmall cell lung cancer (NSCLC).

METHODS:

From January 2010 through November 2011, patients with NSCLC who had resectable disease based on conventional staging were assigned randomly either to coregistered MRI‐PET or WB PET‐CT plus brain MRI (ClinicalTrials.gov trial NCT01065415). The primary endpoint was correct upstaging (the identification of lesions with higher tumor, lymph node, or metastasis classification, verified with biopsy or other diagnostic test) to have the advantage of avoiding unnecessary thoracotomy, to determine appropriate treatment, and to accurately predict patient prognosis. The secondary endpoints were over staging and under staging compared with pathologic staging.

RESULTS:

Lung cancer was correctly upstaged in 37 of 143 patients (25.9%) in the MRI‐PET group and in 26 of 120 patients (21.7%) in the PET‐CT plus brain MRI group (4.2% difference; 95% confidence interval, −6.1% to 14.5%; P = .426). Lung cancer was over staged in 26 of 143 patients (18.2%) in the MRI‐PET group and in 7 of 120 patients (5.8%) in the PET‐CT plus brain MRI group (12.4% difference; 95% confidence interval, 4.8%‐20%; P = .003), whereas lung cancer was under staged in 18 of 143 patients (12.6%) and in 28 of 120 patients (23.3%), respectively (−10.7% difference; 95% confidence interval, −20.1% to −1.4%; P = .022).

CONCLUSIONS:

Although both staging tools allowed greater than 20% correct upstaging compared with conventional staging methods, coregistered MRI‐PET did not appear to help identify significantly more correctly upstaged patients than PET‐CT plus brain MRI in patients with NSCLC. Cancer 2013. © 2013 American Cancer Society.
Mining batch processing workflow models from event logs
Authors: Wen Yiping , Chen Zhigang , Liu Jianxun , Chen Jinjun
Published: February 2013

The employment of batch processing in workflow is to model and schedule activity instances in multiple workflow cases of the same workflow type to optimize business processes execution dynamically. Although our previous works have preliminarily investigated its model and implementation, it is still necessary to deal with its model design problem. Process mining techniques allow for the automated discovery of process models from event logs and have received notable attentions in researches recently. Following these researches, this paper proposes an approach to mine batch processing workflow models from event logs by considering the batch processing relations among activity instances in multiple workflow cases. The notion of batch processing feature and its corresponding mining algorithm are also presented for discovering the batch processing area in the model by using the input and output data information of activity instances in events. The algorithms presented in this paper can help to enhance the applicability of existing process mining approaches and broaden the process mining spectrum. Copyright © 2013 John Wiley & Sons, Ltd.
Electrochemical Modification of Gold Electrodes with Azobenzene Derivatives by Diazonium Reduction
Authors: Kibena Elo , Marandi Margus , Mäeorg Uno , Venarusso Luna B. , Maia Gilberto , Matisen Leonard , Kasikov Aarne , Sammelselg Väino , Tammeveski Kaido
Published: February 2013

An electrochemical study of Au electrodes electrografted with azobenzene (AB), Fast Garnet GBC (GBC) and Fast Black K (FBK) diazonium compounds is presented. Electrochemical quartz crystal microbalance, ellipsometry and atomic force microscopy investigations reveal the formation of multilayer films. The elemental composition of the aryl layers is examined by X‐ray photoelectron spectroscopy. The electrochemical measurements reveal a quasi‐reversible voltammogram of the Fe(CN)63−/4− redox couple on bare Au and a sigmoidal shape for the GBC‐ and FBK‐modified Au electrodes, thus demonstrating that electron transfer is blocked due to the surface modification. The electrografted AB layer results in strongest inhibition of the Fe(CN)63−/4− response compared with other aryl layers. The same tendencies are observed for oxygen reduction; however, the blocking effect is not as strong as in the Fe(CN)63−/4− redox system. The electrochemical impedance spectroscopy measurements allowed the calculation of low charge‐transfer rates to the Fe(CN)63− probe for the GBC‐ and FBK‐modified Au electrodes in relation to bare Au. From these measurements it can be concluded that the FBK film is less compact or presents more pinholes than the electrografted GBC layer.
Two specific populations of GABAergic neurons originating from the medial and the caudal ganglionic eminences aid in proper navigation of callosal axons
Authors: Niquille Mathieu , Minocha Shilpi , Hornung Jean‐Pierre , Rufer Nathalie , Valloton Delphine , Kessaris Nicoletta , Alfonsi Fabienne , Vitalis Tania , Yanagawa Yuchio , Devenoges Christiane , Dayer Alexandre , Lebrand Cécile
Published: February 2013

The corpus callosum (CC) plays a crucial role in interhemispheric communication. It has been shown that CC formation relies on the guidepost cells located in the midline region that include glutamatergic and GABAergic neurons as well as glial cells. However, the origin of these guidepost GABAergic neurons and their precise function in callosal axon pathfinding remain to be investigated. Here, we show that two distinct GABAergic neuronal subpopulations converge toward the midline prior to the arrival of callosal axons. Using in vivo and ex vivo fate mapping we show that CC GABAergic neurons originate in the caudal and medial ganglionic eminences (CGE and MGE) but not in the lateral ganglionic eminence (LGE). Time lapse imaging on organotypic slices and in vivo analyses further revealed that CC GABAergic neurons contribute to the normal navigation of callosal axons. The use of Nkx2.1 knockout (KO) mice confirmed a role of these neurons in the maintenance of proper behavior of callosal axons while growing through the CC. Indeed, using in vitro transplantation assays, we demonstrated that both MGE‐ and CGE‐derived GABAergic neurons exert an attractive activity on callosal axons. Furthermore, by combining a sensitive RT‐PCR technique with in situ hybridization, we demonstrate that CC neurons express multiple short and long range guidance cues. This study strongly suggests that MGE‐ and CGE‐derived interneurons may guide CC axons by multiple guidance mechanisms and signaling pathways. © 2013 Wiley Periodicals, Inc. Develop Neurobiol 73: 647–672, 2013
Optimization, validation, and the application of liquid chromatography‐tandem mass spectrometry for the analysis of new drugs of abuse in wastewater
Authors: van Nuijs Alexander L. N. , Gheorghe Adriana , Jorens Philippe G. , Maudens Kristof , Neels Hugo , Covaci Adrian
Published: February 2013

Recently it was demonstrated that the analysis of drugs of abuse (DOA) in wastewater can be used to track their use in communities. This paper presents the optimization, validation, and application of an analytical procedure based on solid‐phase extraction (SPE) and liquid chromatography coupled to tandem mass spectrometry (LC‐MS/MS) for the determination of some emerging drugs in influent wastewater. The compounds of interest were the cathinone derivatives methylenedioxypyrovalerone (MDPV) and 4‐methylmethcathinone (mephedrone (MEPH)), ketamine (KET) and its metabolites norketamine (NK) and dehydronorketamine (DHNK), as well as the major metabolite of cannabis, 11‐nor‐9‐carboxy‐delta‐9‐tetrahydrocannabinol (THC‐COOH). Except for DHNK, deuterated analogues were used as internal standards for quantification. The use of a short C18 column (50 mm x 2 mm, 3 µm) allowed a good separation for the compounds analyzed in positive ionization mode (KET, NK, DHNK, MDPV, and MEPH) and for THC‐COOH, which was analyzed in negative ionization mode, with a total run time of 13 min. Sample preparation using SPE was optimized by comparing Oasis HLB and Oasis MCX sorbents. The method was validated for each compound by assessing the following parameters: linearity, accuracy, precision, recovery, and relative process efficiency. The lowest calibration level was considered as the lower limit of quantification (LLOQ) and was 5 ng/l for KET, NK, DHNK, MDPV, and MEPH and 20 ng/l for THC‐COOH. KET, and THC‐COOH could be quantified in the majority of wastewater samples from three large wastewater treatment plants in Belgium. The other compounds were below the LLOQ or could not be detected. Copyright © 2013 John Wiley & Sons, Ltd.
Nitrate‐Intercalated Layered Double Hydroxides – Structure Model, Order, and Disorder
Authors: Marappa Shivanna , Radha S. , Kamath P. Vishnu
Published: February 2013

Layered double hydroxides with a high layer charge (+0.33 per empirical formula unit) intercalate nitrate ions with the molecular plane of the NO3– ion inclined at ca. 70° to the metal hydroxide layer, which results in a basal spacing of 8.8 Å. Three different N–O bond lengths are observed and yield Cs coordination symmetry. At lower charge (0.165 ≤ x ≤ 0.2), a basal spacing of 8.0 Å is observed, which indicates that the nitrate ion is intercalated with its molecular plane parallel to the metal hydroxide layer (coordination symmetry D3h) in a manner isostructural with carbonate‐intercalated layered double hydroxides. Consequently, crystal chemical considerations predict the layer charge corresponding to the idealized composition of the nitrate‐intercalated phase to be +0.165 per empirical formula unit. The [Mg–Al–NO3]0.165 phase is highly ordered with robust crystal growth along [001] and is stable to hydrothermal treatment, in contrast to the carbonate analogue of the same layer charge. Phases obtained with intermediate layer charge (+0.20 to 0.25 per empirical formula unit) exhibit structural disorder arising out of (i) planar faults and (ii) random interstratification of layers comprising nitrate ions in different orientations.
Evidence for elevated emissions from high‐latitude wetlands contributing to high atmospheric CH4concentration in the early Holocene
Authors: Yu Zicheng , Loisel Julie , Turetsky Merritt R. , Cai Shanshan , Zhao Yan , Frolking Steve , MacDonald Glen M. , Bubier Jill L.
Published: February 2013

The major increase in atmospheric methane (CH4) concentration during the last glacial‐interglacial transition provides a useful example for understanding the interactions and feedbacks among Earth's climate, biosphere carbon cycling, and atmospheric chemistry. However, the causes of CH4doubling during the last deglaciation are still uncertain and debated. Although the ice‐core data consistently suggest a dominant contribution from northern high‐latitude wetlands in the early Holocene, identifying the actual sources from the ground‐based data has been elusive. Here we present data syntheses and a case study from Alaska to demonstrate the importance of northern wetlands in contributing to high atmospheric CH4concentration in the early Holocene. Our data indicate that new peatland formation as well as peat accumulation in northern high‐latitude regions increased more than threefold in the early Holocene in response to climate warming and the availability of new habitat as a result of deglaciation. Furthermore, we show that marshes and wet fens that represent early stages of wetland succession were likely more widespread in the early Holocene. These wetlands are associated with high CH4emissions due to high primary productivity and the presence of emergent plant species that facilitate CH4transport to the atmosphere. We argue that early wetland succession and rapid peat accumulation and expansion (not simply initiation) contributed to high CH4emissions from northern regions, potentially contributing to the sharp rise in atmospheric CH4at the onset of the Holocene.
Evolution of the sewage treatment plant model SimpleTreat: Use of realistic biodegradability tests in probabilistic model simulations
Authors: Franco Antonio , Struijs Jaap , Gouin Todd , Price Oliver R
Published: February 2013

Given the large number of chemicals under regulatory scrutiny, models play a crucial role in the screening phase of the environmental risk assessment. The sewage treatment plant (STP) model SimpleTreat 3.1 is routinely applied as part of the European Union System for the Evaluation of Substances to estimate the fate and elimination of organic chemicals discharged via sewage. SimpleTreat estimates tend to be conservative and therefore only useful for lower-tier assessments. A probabilistic version of SimpleTreat was built on the updated version of the model (SimpleTreat 3.2, presented in a parallel article in this issue), embracing likeliest as well as worst-case conditions in a statistically robust way. Probabilistic parameters representing the variability of sewage characteristics, STP design, and operational parameters were based on actual STP conditions for activated sludge plants in Europe. An evaluation study was carried out for 4 chemicals with distinct sorption and biodegradability profiles: tonalide, triclosan, trimethoprim, and linear alkylbenzene sulfonate. Simulations incorporated information on biodegradability simulation studies with activated sludge (OECD 314B and OECD 303A tests). Good agreement for both median values and variability ranges was observed between model estimates and monitoring data. The uncertainty analysis highlighted the importance of refined data on partitioning and biodegradability in activated sludge to achieve realistic estimates. The study indicates that the best strategy to refine the exposure assessment of down-the-drain chemicals is by integrating higher-tier laboratory data with probabilistic STP simulations and, if possible, by comparing them with monitoring data for validation. Integr Environ Assess Manag 2013;9:569–579. © 2013 SETAC
Self‐Healing Dynamic Polymeric Systems
Authors: Tyagi Prashant , Deratani André , Quemener Damien
Published: February 2013

The concept of self‐healing has created a paradigm shift in the development of a new kind of responsive polymeric materials, which have traditionally been used in a passive role. Inspired by nature, the advancements made in this nascent field of research have given materials the ability of not only sensing damage but also responding and mending themselves in an appropriate manner. Self‐healing in polymers can be autonomous, without the need for human intervention, or nonautonomous, requiring some form of external stimulus. The latter type involves the incorporation of dynamic bonds within the polymeric system, giving the ability to heal multiple times. This minireview discusses some of the prominent self‐healing polymeric systems that harness different dynamic bond chemistries, with the aim of highlighting the potential of dynamic bonds to prepare such advanced materials.
DNA as a Platform to Program Assemblies with Emerging Functions in Chemical Biology
Authors: Sadhu Kalyan K. , Röthlingshöfer Manuel , Winssinger Nicolas
Published: February 2013

The programmability of oligonucleotide recognition offers an attractive platform for directing the assembly of ligands that can interact cooperatively with a target or the assembly of reactive partner that can engage in chemical reactions. In both cases, an oligonucleotide directs the assembly, which yields a functional output. In terms of the controlled display of ligands, several examples have shown a significant increase in binding upon ligand assembly using small molecule fragments, peptides, glycans, and protein fragments. Combinatorial approaches to identifying the optimal pairing have also been reported. In terms of nucleic acidtriggered reactions, several robust chemistries have been reported, leading to the unmasking of different fluorophores or bioactive molecules as well as the synthesis of a bioactive compound in response to DNA or even cellular RNA. Herein we present the historical context of this work and summarize recent developments in this area.
Drought disturbances increase temporal variability of zooplankton community structure in floodplains
Authors: Simões Nadson R. , Lansac‐Tôha Fábio A. , Bonecker Claudia C.
Published: February 2013

The present study verified how hydrological regime affects the temporal variability of zooplankton communities in floodplains. Multidimensional methods were employed to characterise community variability, and the temporal trend of the community was also evaluated using a matrices comparison procedure. In connected ponds from the main river, the absence of floods (drought) modified the variability of the zooplankton community by increasing temporal dissimilarity of community. In these environments, the periodic input of water due to floods maintained a lower variability of environmental characteristics, sustaining a lower temporal variability of the community. This observation suggests that, in floodplains, flooding is a component of the system that assists with both the maintenance of ecological processes (temporal variability of the community) and the high biodiversity of these environments. This study therefore suggests that the temporal variability of communities in floodplains is increased by extended droughts, and emphasises the importance of flood dynamics to maintain temporal stability of zooplankton communities in river floodplain systems.
Medications and therapeutic apheresis procedures: Are we doing our best?
Authors: Ibrahim Rami B. , Balogun Rasheed Abiodun
Published: February 2013

Therapeutic apheresis refers to a group of extracorporeal therapies commonly used in the treatment of a variety of neurological, renal, hematological, and other systemic diseases caused by circulating “toxic agents” that cannot be cleared by other means. This article presents an overview of the concepts underlying the effect of therapeutic apheresis procedures on prescription drugs taken by patients and describes key drug‐related and procedure‐related factors that may impact drug disposition during therapeutic apheresis. Therapeutic apheresis, and specifically therapeutic plasma exchange (TPE), is the process involving the extracorporeal separation of plasma from the cellular components of blood, discarding the plasma and exchanging it with replacement physiologic fluids such as albumin or fresh frozen plasma to maintain oncotic pressure and blood volume, and then returning this and the original cellular components of blood back to the patient's circulatory system (Ibrahim and Balogun, Semin Dial 2012;25:176‐189). Over the last 4 decades, modern therapeutic apheresis has been used clinically for the treatment of a host of renal, hematological, and neurological diseases such as Goodpasture's syndrome, thrombotic thrombocytopenic purpura, and myasthenia gravis to name a few (Ibrahim et al., Pharmacotherapy 2007;27:1529‐1549). Because of its ability to remove plasma, TPE can extract circulating drugs residing in this compartment, thereby affecting their disposition and potentially their therapeutic action (Ibrahim and Balogun, Semin Dial 2012;25:176‐189; Ibrahim et al., Pharmacotherapy 2007;27:1529‐1549; Kale‐Pradhan and Woo, Pharmacotherapy 1997;17:684‐695; Kintzel et al., J Clin Apher 2003;18:194‐205). The aim of this article is to shed light on drug‐related and TPE‐related factors that may influence drug removal by TPE. Emphasis is put on areas needing improvement in the way of assessing drug removal by TPE. In addition, a call for an expanded investigation of TPEs influence on select compounds is enlisted. J. Clin. Apheresis 28:73–77, 2013. © 2013 Wiley Periodicals, Inc.
Enhancement of oxygen mass transfer coefficients in a hybrid membrane bioreactor
Authors: Zerari Kamel , Seyssieq Isabelle , Akretche Djamal‐Eddine , Roche Nicolas
Published: February 2013

Background

Oxygen mass transfer is a key parameter for processing aerobic bioreactors in terms of operational costs and efficiency. In membrane bioreactors, a reduction of the aeration capacity is often observed at high solid ratios, caused by the presence of solids and the non‐Newtonian properties of activated sludge.

Results

The aim of this work is to study how oxygen transfer is impacted when a high porosity packing material is added (free bacteria plus fixed bio‐films). Measurements are performed on a pilot scale ‘hybrid membrane bioReactor’ (HMBR), using clear water, a Newtonian solid suspension and a non‐Newtonian solution. The influence on the oxygen transfer coefficient (kLa) of non‐Newtonian properties, the presence of solids, the presence of a packing material and of the air flowrate, are presented. It is observed that the type of fluid used and the presence of a packing material both have a strong influence.

Conclusion

An important drop in kLa (respectively 53% and 31%) is obtained with the non‐Newtonian solution and the physico‐chemical suspension, compared with water. On the contrary, an enhancement in kLa, up to 46% is observed in the presence of a packing material. The air flow rate has little influence in the range of parameters investigated here. © 2013 Society of Chemical Industry
Stereotypic Laryngeal and Respiratory Motor Patterns Generate Different Call Types in Rat Ultrasound Vocalization
Authors: RIEDE TOBIAS
Published: February 2013

Rodents produce highly variable ultrasound whistles as communication signals unlike many other mammals, who employ flow‐induced vocal fold oscillations to produce sound. The role of larynx muscles in controlling sound features across different call types in ultrasound vocalization (USV) was investigated using laryngeal muscle electromyographic (EMG) activity, subglottal pressure measurements and vocal sound output in awake and spontaneously behaving Sprague–Dawley rats. Results support the hypothesis that glottal shape determines fundamental frequency. EMG activities of thyroarytenoid and cricothyroid muscles were aligned with call duration. EMG intensity increased with fundamental frequency. Phasic activities of both muscles were aligned with fast changing fundamental frequency contours, for example in trills. Activities of the sternothyroid and sternohyoid muscles, two muscles involved in vocal production in other mammals, are not critical for the production of rat USV. To test how stereotypic laryngeal and respiratory activity are across call types and individuals, sets of ten EMG and subglottal pressure parameters were measured in six different call types from six rats. Using discriminant function analysis, on average 80% of parameter sets were correctly assigned to their respective call type. This was significantly higher than the chance level. Since fundamental frequency features of USV are tightly associated with stereotypic activity of intrinsic laryngeal muscles and muscles contributing to build‐up of subglottal pressure, USV provide insight into the neurophysiological control of peripheral vocal motor patterns. J. Exp. Zool. 319A:213–224, 2013. © 2013 Wiley Periodicals, Inc.
Native soil bacteria isolates in Mexico exhibit a promising antagonistic effect against Fusarium oxysporum f. sp. radicis‐lycopersici
Authors: Cordero‐Ramírez Jesús Damián , López‐Rivera Raquel , Figueroa‐Lopez Alejandro Miguel , Mancera‐López María Elena , Martínez‐Álvarez Juan Carlos , Apodaca‐Sánchez Miguel Ángel , Maldonado‐Mendoza Ignacio Eduardo
Published: February 2013

Sinaloa state accounts for 23% of Mexico's tomato production. One constraint on this important crop is the Fusarium crown and root rot, caused by Fusarium oxysporum f. sp. radicis‐lycopersici, which has been reported to reduce crop yield by up to 50%. In this study, we set out to identify bacterial populations which could be used to control this disease through natural antagonism. Five tomato rhizospheric soil samples were collected, dried for 1‐week, and homogenized. Sub‐samples were used to prepare an aqueous solution used to isolate microorganisms in pure cultures. Organisms were purified and grown separately, and used to generate a collection of 705 bacterial isolates. Thirty‐four percent from this bank (254 strains) was screened against Forl, finding 27 bacteria displaying in vitro Forl growth inhibition levels from 5% to 60%. These isolates belonged to the genus Bacillus and their 16Sr DNA sequences showed that they are closely related to seven species and they were putatively designated as: B. subtilis, B. cereus, B. amyloliquefaciens, B. licheniformis, B. thuringiensis, B. megaterium, and B. pumilus. One isolate belonged to the genus Acinetobacter. Two B. subtilis isolates (144 and 151) and one B. cereus isolate (171) showed the best antagonistic potential against FCRRT when evaluated on seedlings. Plate and activity assays indicate that these isolates include a diverse repertoire of functional antagonistic traits that might explain their ability to control FCRRT. Moreover, bacteria showed partial hemolytic activity, and future research will be directed at ensuring that their application will be not harmful for humans and effective against Forl in greenhouse or field conditions.
Cultural Difference in Stereotype Perceptions and Performances in Nonverbal Deductive Reasoning and Creativity
Authors: Wong Regine , Niu Weihua
Published: February 2013

A total of 182 undergraduate students from China and the United States participated in a study examining the presence of stereotypical perceptions regarding creativity and deductive reasoning abilities, as well as the influence of stereotype on participants' performance on deductive reasoning and creativity in nonverbal form. The results showed that participants from both China and the United States believed that Americans have better creativity abilities than Chinese and that Chinese have better deductive reasoning skills than Americans. Significant cultural difference in the performances on the measures of creativity was found. The cultural difference in deductive reasoning was found between Chinese participants in China and the Caucasian (not the Asian) participants in the United States, which were somewhat congruent to the stereotypical perceptions. However, the study did not find that stereotypic perceptions directly influenced participants' performance on deductive reasoning and creativity.