bluuebunny/crossref_metadata_2025 huggingface dataset:
Détermination de l'altitude du Zéro des stations hydrométriques en Amazonie brésilienne. Application aux lignes d'eau des Rios Negro, Solimões et Amazone
Authors: Callède Jacques , Moreira Daniel Medeiros , Calmant Stéphane
Published: August 2013

Le rattachement altimétrique d’une station hydrométrique à un repère du Nivellement Général est habituellement effectué dans le but de connaître, lorsqu’il y a plusieurs stations, la pente de la ligne d’eau. Jusqu’à la fin de la décennie 2000, les stations hydrométriques amazoniennes n’étaient pas rattachées car le manque de réseau routier était un obstacle majeur au classique nivellement direct. Mais la fin de cette décennie a vu l'expansion de l'altimétrie satellitaire, et plus particulièrement celle de la méthode utilisant le GPS associé à l'utilisation du modèle de géoïde EGM08. Cette nouvelle technique est particulièrement précieuse pour niveler les stations hydrométriques du bassin amazonien. Nous avons traité ici les stations hydrométriques de l'Amazone depuis son embouchure jusqu’à la frontière Brésil/Pérou et celles des rios Negro et Solimões pour leurs parties brésiliennes. Les pentes moyennes de ces différents biefs décroissent normalement sur le Rio Solimões et l'Amazone, tandis que le bief Moura-Manaus, sur le Rio Negro, présente anormalement une pente très faible (6 mm•km‑1) au risque de provoquer des inversions d'écoulement. Le Bas Amazone est raccordé à l'altitude donnée par la trace de l'orbite 202 des satellites Topex-Poseidon et Jason-1 mais malheureusement nous ne disposons que d'une seule année de relevés limnigraphiques sur ce tronçon. Les comparaisons des pentes de la ligne d’eau avec d’autres fleuves (Volga, Danube, Nil, Mississipi et Rhin) indiquent que la pente de l’Amazone est, avec en moyenne 21 mm•km‑1 de Tabatinga (frontière Brésil/Pérou) à l’Océan Atlantique (soit sur 3 000 km) deux fois moindre que celle de la Volga (qui présente la ligne d’eau de pente la plus faible sur les cinq fleuves étudiés). Ceci, associé au fait que le fond du lit de l’Amazone est, sur 2 000 km à partir de son embouchure, à une quarantaine de mètres en-dessous du niveau de l’océan, nous conduirait à penser que l’écoulement du fleuve subit une poussée des eaux amont, issues de la Cordillère des Andes.
Multivitamin supplementation improves haematologic status in children born to HIV‐positive women in Tanzania
Authors: Liu Enju , Duggan Christopher , Manji Karim P , Kupka Roland , Aboud Said , Bosch Ronald J , Kisenge Rodrick R , Okuma James , Fawzi Wafaie W
Published: August 2013

Introduction

Anaemia is prevalent among children born to HIV‐positive women, and it is associated with adverse effects on cognitive and motor development, growth, and increased risks of morbidity and mortality.

Objective

To examine the effect of daily multivitamin supplementation on haematologic status and mother‐to‐child transmission (MTCT) of HIV through breastfeeding.

Methods

A total of 2387 infants born to HIV‐positive women from Dar es Salaam, Tanzania were enrolled in a randomized, double‐blind, placebo‐controlled trial, and provided a daily oral supplement of multivitamins (vitamin B complex, C and E) or placebo at age 6 weeks for 24 months. Among them, 2008 infants provided blood samples and had haemoglobin concentrations measured at baseline and during a follow‐up period. Anaemia was defined as haemoglobin concentrations<11 g/dL and severe anaemia<8.5 g/dL.

Results

Haemoglobin concentrations among children in the treatment group were significantly higher than those in the placebo group at 12 (9.77 vs. 9.64 g/dL, p=0.03), 18 (9.76 vs. 9.57 g/dL, p=0.004), and 24 months (9.93 vs. 9.75 g/dL, p=0.02) of follow‐up. Compared to those in the placebo group, children in the treatment group had a 12% lower risk of anaemia (hazard ratio (HR): 0.88; 95% CI: 0.79–0.99; p=0.03). The treatment was associated with a 28% reduced risk of severe anaemia among children born to women without anaemia (HR: 0.72; 95% CI: 0.56–0.92; p=0.008), but not among those born to women with anaemia (HR: 1.10; 95% CI: 0.79–1.54; p=0.57; p for interaction=0.007). One thousand seven hundred fifty three infants who tested HIV‐negative at baseline and had HIV testing during follow‐up were included in the analysis for MTCT of HIV. No association was found between multivitamin supplements and MTCT of HIV.

Conclusions

Multivitamin supplements improve haematologic status among children born to HIV‐positive women. Further trials focusing on anaemia among HIV‐exposed children are warranted in the context of antiretroviral therapy.
Future Arctic Research: Integrative Approaches to Scientific and Methodological Challenges
Authors: Schmale Julia , Lisowska Maja , Smieszek Malgorzata
Published: August 2013

Climate change has significant consequences for both the natural environment and the socioeconomics in the Arctic. The complex interplay between the changing atmosphere, cryosphere, and ocean is responsible for a multitude of feedbacks and cascading effects leading to changes in the marine and terrestrial ecosystems, the sea ice cycle, and atmospheric circulation patterns. The warming Arctic has also become a region of economic interest as shipping, natural resource exploitation, and tourism are becoming achievable and lucrative with declining sea ice. Such climatic and anthropogenic developments are leading to profound changes in the Arctic, its people, and their cultural heritage.
Characterizing the dynamics of geyser eruptions
Authors: Balcerak Ernie
Published: August 2013

Some geysers have predictable eruptions that make them ideal for study. Understanding geyser eruption dynamics can provide insight into other intermittent natural processes, such as volcanic eruptions, but most studies of geysers have focused on the processes that trigger geyser eruption. The eruption jet dynamics are less well characterized.
Photonic Crystal Nanocavities Containing Plasmonic Nanoparticles Assembled Using a Laser‐Printing Technique
Authors: Do Jaekwon , Sediq Khalid N. , Deasy Kieran , Coles David M. , Rodríguez‐Fernández Jessica , Feldmann Jochen , Lidzey David G.
Published: August 2013

An optical printing technique is used to accurately position a 150 nm diameter gold nanoparticle onto a submicrometer linear three‐hole defect of a photonic crystal nanocavity. It is shown (using both experiment and finite‐difference time domain modelling), that there is an electromagnetic interaction between the nanoparticle and the cavity mode, with the electromagnetic field within the cavity being dissipated by driving the nanoparticle plasmon resonance. The use of a printing technique to selectively position nanoparticles onto a surface‐accessible cavity potentially allows the hybridisation between electronic, excitonic, and optical states to be explored with high precision. Furthermore, through its scalable nature it also opens possibilities for the routine construction of new types of photonic devices and sensors.
Visible Light‐Mediated Synthesis of (Spiro)anellated Furans
Authors: Kachkovskyi Georgiy , Faderl Christian , Reiser Oliver
Published: August 2013

Visible light‐mediated decarboxylation using N‐acyloxyphthalimides as the source for carbon‐centered radicals was applied for the synthesis of spirobutenolides. The utility of this approach is demonstrated with the formal synthesis of (S)‐(+)‐lycoperdic acid. Alternatively, 2,3‐anellated furans can be obtained in a one‐pot procedure via photocyclization following a regioselective semipinacol rearrangement.

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Efficient One‐Pot Synthesis of Multi‐Substituted Dihydrofurans by Ruthenium(II)‐Catalyzed [3+2] Cycloaddition of Cyclic or Acyclic Diazodicarbonyl Compounds with Olefins
Authors: Xia Likai , Lee Yong Rok
Published: August 2013

Ruthenium(II)‐phosphine complexes‐catalyzed [3+2] cycloadditions were conducted to synthesize a variety of dihydrofurans by reactions of cyclic or acyclic diazodicarbonyl compounds with olefins. This method represents a direct and efficient one‐pot synthesis for multi‐substituted dihydrofurans under mild reaction conditions with an excellent regioselectivity. Furthermore, to reduce reaction times and increase yields of dihydrofurans, microwave‐assisted tris(triphenylphosphine)ruthenium(II) chloride/ 1‐butyl‐3‐methylimidazolium tetrafluoroborate {Ru(PPh3)3Cl2/[Bmim]BF4}‐catalyzed reactions were also developed. The synthesized dihydrofurans can be readily converted into biologically interesting tetrahydroindoles.

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Synthesis of Carbazoles via One‐Pot Copper‐Catalyzed Amine Insertion into Cyclic Diphenyleneiodoniums as a Strategy to Generate a Drug‐Like Chemical Library
Authors: Zhu Daqian , Liu Qi , Luo Bingling , Chen Meihui , Pi Rongbiao , Huang Peng , Wen Shijun
Published: August 2013

Carbazoles have attracted high interest among synthetic chemists due to their unique structural features and potential pharmacological activities. Compared to linear aryliodoniums, cyclic diphenyleneiodoniums are more inert and have not attracted much attention to their application as building blocks. Employing our synthetic strategy, diversified carbazoles can be efficiently obtained from a single cyclic diphenyleneiodonium under mild conditions. The reactions catalyzed by copper(II) acetate have provided a variety of carbazoles in modest to good yields with a broad range of amines including anilines, aliphatic amines and sulfonamides. Moreover, one of the obtained carbazoles has displayed an outstanding ability to protect HT‐22 neuronal cells from the damage induced by neurotoxins glutamate and homocysteic acid.

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N‐Benzylation/Benzylic CH Amidation Cascade by the (η3‐Benzyl)palladium System in Aqueous Media: An Effective Pathway for the Direct Construction of 3‐Phenyl‐3,4‐dihydro‐ (2H)‐1,2,4‐benzothiadiazine 1,1‐Dioxides
Authors: Hikawa Hidemasa , Matsuda Naoya , Suzuki Hideharu , Yokoyama Yuusaku , Azumaya Isao
Published: August 2013

We demonstrate a unique strategy for a benzylation/benzylic CH amidation cascade reaction by the (η3‐benzyl)palladium system derived from a palladium catalyst and benzyl alcohol. This tandem process is devised as a new synthetic route for 3‐phenyl‐3,4‐dihydro‐(2H)‐1,2,4‐benzothiadiazine‐1,1‐dioxide. Water plays an important role for the smooth generation of the (η3‐benzyl)palladium species, and a bis‐benzylated Pd(II) intermediate would be formed in our catalytic system. Atom economical processes such as benzylic CH activation, cascade reactions and chemoselective reactions in aqueous media have been developed.

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Dehydrogenative Heck Reaction (Fujiwara–Moritani Reaction) of Unactivated Olefins with Simple Dihydropyrans under Aprotic Conditions
Authors: Pawar Govind Goroba , Singh Gaurav , Tiwari Virendra Kumar , Kapur Manmohan
Published: August 2013

The dehydrogenative Heck coupling (Fujiwara–Moritani reaction) of unactivated olefins with 3,4‐dihydro‐2H‐pyrans is described. The two main highlights of the work are the use of unconventional unactivated olefins as coupling partners in the palladium‐catalyzed reaction and the use of aprotic conditions for the coupling reaction of the acid‐labile dihydropyrans.

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Switchable Synthesis of 3‐Cyanoindoles and 3‐Amidylindoles via a Palladium‐Catalyzed Reaction of N,N‐Dimethyl‐2‐alkynylaniline with Isocyanide
Authors: Qiu Guanyinsheng , Qiu Xiaochen , Liu Jianping , Wu Jie
Published: August 2013

A palladium‐catalyzed reaction of N,N‐dimethyl‐2‐alkynylanilines with isocyanides is reported, leading to the formation of 3‐cyanoindoles and 3‐amidylindoles. The isocyanide insertion is the key step during the process, and the presence of water is essential for the formation of 3‐amidylindoles.

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Stereoselective Synthesis with Carbon Dioxide
Authors: Kielland Nicola , Whiteoak Christopher J. , Kleij Arjan W.
Published: August 2013

Homogeneous catalysis employing carbon dioxide (CO2) as a carbon‐based renewable feedstock has been and continues to be a flourishing area of research, providing new and improved synthetic methodologies towards a range of organic products. Since CO2 is inexpensive, non‐toxic and available in virtually unlimited amounts, the progress in CO2 catalysis is of widespread academic, industrial and societal interest. This interest is sparked by the demanding necessity to provide viable alternatives for fossil fuel‐derived organic precursors and their post‐modification. Whereas most of the advances have been made in the area of CO2 conversion focusing on simple organic structures, the more challenging and gratifying stereoselective syntheses have only recently become a subject of increasing attention. This review therefore aims at presenting a concise overview of the most recent achievements in the field of stereoselective transformations where CO2 is used as a key reagent. As such, it should empower the synthetic community with a starting point for expansion of the toolbox leading to a greater variety of value‐added organic matter based on CO2.

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Palladium nanoparticles supported on silica diphenylphosphinite as efficient catalyst for C‐O and C‐S arylation of aryl halides
Authors: Iranpoor Nasser , Firouzabadi Habib , Rostami Abed
Published: August 2013

Silica diphenylphosphinite (SDPP) can be easily obtained through direct phosphorylation of silica gel. Further reaction of SDPP with Pd(II) produces nano Pd(0)/SDPP. This nano Pd(0) catalyst exhibits excellent reactivity for the C‐O and C‐S arylation of different aryl iodides, bromides and chloride with phenols and thiophenols. This heterogeneous catalyst shows excellent recyclability and can be easily recovered and reused for several runs. Copyright © 2013 John Wiley & Sons, Ltd.
Physical properties of poly lactic acid/clay nanocomposite films: Effect of filler content and annealing treatment
Authors: Russo Pietro , Cammarano Sara , Bilotti Emiliano , Peijs Ton , Cerruti Pierfrancesco , Acierno Domenico
Published: August 2013

Polylactic acid (PLA)‐based nanocomposite films, containing up to 5% by weight of two types of nanoclays: sepiolite needle‐like clay and halloysite nanotube clay, were prepared via industrially viable melt processing route. Clays modify the crystallinity of the hosting PLA affecting its gas barrier and mechanical properties. Annealing treatments of composite films were found to be critical in the optimization of these properties with an additional enhancement in crystallinity and stiffness especially in presence of clays. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39798.
Hydrothermal Realization of a Hierarchical, Flowerlike MnWO4@MWCNTs Nanocomposite with Enhanced Reversible Li Storage as a New Anode Material
Authors: Shim Hyun‐Woo , Lim Ah‐Hyeon , Kim Jae‐Chan , Lee Gwang‐Hee , Kim Dong‐Wan
Published: August 2013

A phase‐pure MnWO4‐based nanocomposite, MnWO4@MWCNTs (MWCNTs=multiwalled carbon nanotubes), was successfully synthesized through a simple hydrothermal reaction at 180 °C by adjusting the pH of the precursor medium. The resulting nanocomposite maintains the original flowerlike morphology of MnWO4 with hierarchical structures composed of numerous single‐crystalline nanorods that drive growth preferentially along the [001] direction. The growth mechanism for the flowerlike formations is also discussed. In addition, the Li electroactivity of pure MnWO4 and MnWO4@MWCNTs electrodes was investigated. As an anode for Li‐ion batteries, the MnWO4@MWCNTs nanocomposite showed enhanced electrochemical performance in reversible Li storage relative to that shown by bare MnWO4 electrodes, including a high capacity of 425 mAh g−1 and superior rate performance. This performance can be attributed to the synergistic effect of the nanocomposite combined with the MWCNTs, which provide efficient electron transport in their role as a conductor.
Neural interconnections between portio minor and portio major at the porus trigeminus: Application to failed surgical treatment of trigeminal neuralgia
Authors: Tubbs R. Shane , Griessenauer Christoph J. , Hogan Elizabeth , Loukas Marios , Cohen‐Gadol Aaron A.
Published: August 2013

Recalcitrant trigeminal neuralgia following surgical treatment can be a life‐altering condition. To explore alternative anatomic reasons for such a complication, the authors examined the potential for nerve connections between the sensory and motor roots of the trigeminal nerve at the opening of Meckel's cave (porus trigeminus). In 15 embalmed adult cadavers (30 sides), the authors performed microdissection of the skull base and specifically at the opening of Meckel's cave. Two sides (6.67%) were found to have interneural connections between the sensory and motor roots at Meckel's cave. These occurred in one male and one female cadaver, both on right sides. Both connections were histologically verified to be neural and were 0.5 mm in diameter and 2.2 and 3.2 mm in length, respectively. Both connections traveled in an oblique fashion from the portio major to the portio minor. On the basis of authors' findings, the sensory and motor components of the trigeminal nerve at the opening of Meckel's cave may be interconnected with a neural anastomosis. Such findings may be of use during the surgical treatment of trigeminal neuralgia or other surgery of the posterior fossa so that inadvertent transection or traction does not occur. Clin. Anat. 27:94–96, 2014. © 2013 Wiley Periodicals, Inc.
Soft Scorpionate Anions as Platforms for Novel Heterocycles
Authors: Rajasekharan‐Nair Rajeev , Marckwordt Annemarie , Lutta Samuel T. , Schwalbe Matthias , Biernat Anne , Armstrong David R. , Watson Allan J. B. , Kennedy Alan R. , Reglinski John , Spicer Mark D.
Published: August 2013

Soft scorpionates have thus far been seen mainly as a family of ligands. Their chemistry is extended here to the production of novel cationic macrocycles using dihaloalkanes. By replacing the dihaloalkanes with mild oxidising agents (NO+, I2) we obtain two unique polycyclic heterocycles. The mechanism which leads to the formation of these polycyclic heterocycles is investigated using ab initio DFT calculations.
Polymeric Micelles for Multidrug Delivery and Combination Therapy
Authors: Aw Moom Sinn , Kurian Mima , Losic Dusan
Published: August 2013

The use of conventional therapy based on a single therapeutic agent is not optimal to treat human diseases. The concept called “combination therapy”, based on simultaneous administration of multiple therapeutics is recognized as a more efficient solution. Interestingly, this concept has been in use since ancient times in traditional herbal remedies with drug combinations, despite mechanisms of these therapeutics not fully comprehended by scientists. This idea has been recently re‐enacted in modern scenarios with the introduction of polymeric micelles loaded with several drugs as multidrug nanocarriers. This Concept article presents current research and developments on the application of polymeric micelles for multidrug delivery and combination therapy. The principles of micelle formation, their structure, and the developments and concept of multidrug delivery are introduced, followed by discussion on recent advances of multidrug delivery concepts directed towards targeted drug delivery and cancer, gene, and RNA therapies. The advantages of various polymeric micelles designed for different applications, and new developments combined with diagnostics and imaging are elucidated. A compilation work from our group based on multidrug‐loaded micelles as carriers in drug‐releasing implants for local delivery systems based on titania nanotubes is summarized. Finally, an overview of recent developments and prospective outlook for future trends in this field is given.
EnantioselectiveToxic Effects and Degradation of Myclobutanil Enantiomers in Scenedesmus obliquus
Authors: Cheng Cheng , Huang Ledan , Diao Jinling , Zhou Zhiqiang
Published: August 2013

Research on the enantioselective environmental behavior of chiral pesticides has been a hot spot of environmental chemistry recently. In this study, the acute toxicity of myclobutanil enantiomers was investigated with the aquatic algae Scendesmus obliquus. After exposure for 96 h, the EC50 values for (−)‐myclobutanil, rac‐myclobutanil and (+)‐myclobutanil were 3.951, 2.760, and 2.128 mg/L, respectively. The photosynthetic pigment (chlorophyll a, chlorophyll b, and carotenoids) and antioxidant enzyme activities catalase (CAT) were determined to evaluate the different toxic effects when S. obliquus were exposed to 1.5, 5 and 15 mg/L of rac‐myclobutanil, (−)‐myclobutanil, and (+)‐myclobutanil for 96 h, respectively. In addition, the degradation of myclobutanil enantiomers in S. obliquus was also studied. Myclobutanil in the medium inoculated with algae degraded faster than in the uninoculated medium. The degradation of (−)‐myclobutanil was faster than that of (+)‐myclobutanil at a concentration of 3 mg/L. On the basis of these data, the acute toxicity and toxic effects of myclobutanil against S. obliquus were concluded to be enantioselective, and such enantiomeric differences should be taken into consideration in pesticide risk assessment. Chirality 25:858–864, 2013. © 2013 Wiley Periodicals, Inc.
Adjuvant leuprolide with or without docetaxel in patients with high‐risk prostate cancer after radical prostatectomy (TAX‐3501)
Authors: Schweizer Michael T. , Huang Peng , Kattan Michael W. , Kibel Adam S. , de Wit Ronald , Sternberg Cora N. , Epstein Jonathan I. , Eisenberger Mario A.
Published: August 2013

BACKGROUND

The current trial evaluated 2 common therapies for patients with advanced prostate cancer, docetaxel and hormonal therapy (HT), in the surgical adjuvant setting.

METHODS

TAX‐3501 was a randomized, phase 3, adjuvant study post‐radical prostatectomy (RP) in high‐risk patients with prostate cancer (n = 228) comparing 18 months of HT with (CHT) without docetaxel chemotherapy either immediately (I) or deferred (D). High‐risk disease was defined as a 5‐year freedom‐from‐disease‐progression rate of ≤ 60% as predicted by a post‐RP nomogram. Progression‐free survival (PFS), including prostate‐specific antigen disease recurrence, was the primary endpoint. The authors also assessed the accuracy of the nomogram and analyzed testosterone recovery in 108 patients treated with HT who had at least 1 posttreatment testosterone value.

RESULTS

Between December 2005 and September 2007, 228 patients were randomized between the treatment cohorts. TAX‐3501 was terminated prematurely because of enrollment challenges, leaving it underpowered to detect differences in PFS. After a median follow‐up of 3.4 years (interquartile range, 2.3‐3.8 years), 39 of 228 patients (17%) demonstrated PSA disease progression, and metastatic disease progression occurred in 1 patient. The median time to baseline testosterone recovery after the completion of treatment was prolonged at 487 days (95% confidence interval, 457‐546 days). The nomogram's predicted versus observed freedom from disease progression was significantly different for the combination D(HT) and D(CHT) group (P < .00001).

CONCLUSIONS

TAX‐3501 illustrated several difficulties involved in conducting postoperative adjuvant systemic trials in men with high‐risk prostate cancer: the lack of consensus regarding patient selection and treatment, the need for long follow‐up time, nonvalidated intermediate endpoints, evolving standard approaches, and the need for long‐term research support. Except for selected patients at very high‐risk of disease recurrence and death, surgical adjuvant trials in patients with prostate cancer may not be feasible. Cancer 2013;119:3610–3618. © 2013 American Cancer Society.
Isolation and Enrichment of Pathogens with a Surface‐Modified Aluminium Chip for Raman Spectroscopic Applications
Authors: Pahlow Susanne , Kloß Sandra , Blättel Verena , Kirsch Konstantin , Hübner Uwe , Cialla Dana , Rösch Petra , Weber Karina , Popp Jürgen
Published: August 2013

We developed a Raman‐compatible chip for isolating microorganisms from complex media. The isolation of bacteria is achieved by using antibodies as capture molecules. Due to the very specific interaction with the targets, this approach is promising for isolation of bacteria even from complex matrices such as body fluids. Our choice of capture molecules also enabled the investigation of samples containing yet unidentified bacteria, as the antibodies can capture a large variety of bacteria based on their analogue cell wall surface structures. The capability of our system is demonstrated for a broad range of different Gram‐positive and Gram‐negative germs. Subsequent identification is done by recording Raman spectra of the bacteria. Further, it is shown that classification with chemometric methods is possible.
The Mechanism of Glucose Isomerization to Fructose over Sn‐BEA Zeolite: A Periodic Density Functional Theory Study
Authors: Yang Gang , Pidko Evgeny A. , Hensen Emiel J. M.
Published: August 2013

The isomerization of glucose to fructose in the presence of Sn‐containing zeolite BEA (beta polymorph A) was studied by periodic DFT calculations. Focus was placed on the nature of the active site and the reaction mechanism. The reactivities of the perfect lattice SnIV site and the hydroxylated SnOH species are predicted to be similar. The isomerization activity of the latter can be enhanced by creating an extended silanol nest in its vicinity. Besides the increased Lewis acidity and coordination flexibility of the Sn center, the enhanced reactivity in this case is ascribed to the reaction environment that promotes activation of the confined sugar intermediates through hydrogen bonding. The resulting multidentate activation of the substrate favors the rate‐determining hydrogen‐shift reaction. These findings suggest the important role of defect lattice sites in Sn‐BEA for catalytic glucose isomerization.
Optimization of the C11‐BODIPY581/591 dye for the determination of lipid oxidation in Chlamydomonas reinhardtii by flow cytometry
Authors: Cheloni Giulia , Slaveykova Vera I.
Published: August 2013

Lipid oxidation is a recognized end point for the study of oxidative stress and is an important parameter to describe the mode of micropollutant action on aquatic microorganisms. Therefore, the development of quick and reliable methodologies probing the oxidative stress and damage in living cells is highly sought. In the present proof‐of‐concept work, we examined the potential of the fluorescent dye C11‐BODIPY591/581 to probe lipid oxidation in the green microalga Chlamydomonas reinhardtii. C11‐BODIPY591/581 staining was combined with flow cytometry measurements to obtain multiparameter information on cellular features and oxidative stress damage within single cells. First, staining conditions were optimized by exploring the capability of the dye to stain algal cells under increasing cell and dye concentrations and different staining procedures. Then lipid oxidation in algae induced by short‐ and long‐term exposures to the three metallic micropollutants, copper, mercury, and nanoparticulate copper oxide, and the two organic contaminants, diethyldithiocarbamate (DDC) and diuron was determined. In this work we pointed out C11‐BODIPY591/581 applicability in a wide range of exposure conditions, including studies of oxidation as a function of time and that it is suitable for in vivo measurements of lipid oxidation due to its high permeation and stability in cells and its low interference with algal autofluorescence. © 2013 International Society for Advancement of Cytometry
From “Click” to “Fenton” chemistry for 5‐bromo‐2′‐deoxyuridine determination
Authors: Cappella Paolo , Giansanti Vincenzo , Pulici Maurizio , Gasparri Fabio
Published: August 2013

Ascorbic acid (AA) and copper have been increasingly employed in flow cytometry (FCM) and high content analysis (HCA) since the introduction of “click chemistry” as a non‐destructive alternative to classical 5‐bromo‐2′‐deoxyuridine (BrdU) immunodetection for DNA synthesis and proliferation assays. Mixtures of ascorbate and catalytic copper, under certain experimental conditions, act as oxidizing agent, catalyzing the formation of reactive hydroxyl radicals through hydrogen peroxides decomposition via Fenton reaction. We developed a procedure for BrdU incorporation detection based on the use of AA and cupric ions as DNA damaging agents. Optimal DNA damaging conditions were identified and found to provide results comparable with “click” 5‐ethynyl‐deoxyuridine (EdU) cycloaddition approach and classical BrdU immunodetection. Scavenger agents were found to prevent hydroxyl‐induced DNA damages, providing the proof‐of‐concept for the use of this procedure for DNA denaturation prior to BrdU detection. We demonstrated hydroxyl radicals' reaction to be readily applicable to HCA and FCM assays, for both classical BrdU immunostaining and EdU cycloaddition procedure. This technique was successfully employed for BrdU pulse‐chase experiments and in multiparametric immunofluorescence assays for the simultaneous detection of labile phosphoproteins in intact cells. The use of AA/Cu prior to immunodetection for BrdU incorporation assays is a viable alternative to chemical/physical DNA denaturing agents (acids or heat), since it allows preservation of labile epitopes such as phosphoproteins, and over enzymatic agents (digestion with DNases) for its lower cost. © 2013 International Society for Advancement of Cytometry
C–S and C–Se Bond Formation at Bridging Vinyliminium Ligands in Diiron Complexes
Authors: Marchetti Fabio , Zacchini Stefano , Zanotti Valerio
Published: August 2013

The vinyliminium complexes [Fe2{μ‐η1:η3‐C(R)C(R)CN(Me)2}(μ‐CO)(CO)(Cp)2][SO3CF3] (R = Me, 3a; R = CO2Me, 3b; R = Ph, 3c) were treated with S8 in the presence of tBuLi, undergoing fragmentation and affording the corresponding six‐membered metallacyclic complexes [Fe(Cp)(CO){SC(R)=C(R)C(NMe2)S}] (5a–c). Complexes 5a–c result from cleavage of the diiron precursor and addition of S to the vinyliminium ligand to generate a dithiochelating ligand. Analogous reactions of the vinyliminium complexes [Fe2{μ‐η1:η3‐C(R)C(R)CN(Me)(Xyl)}(μ‐CO)(CO)(Cp)2][SO3CF3] (R = Me, 3d; R = CO2Me, 3e), which contain a Xyl group (Xyl = 2,6‐Me2C6H3) in place of a methyl, displayed a different outcome. Complex 3d afforded the diiron complex [Fe2{μ‐η1:η3‐C(Me)=C(CS2)C=N(Me)(Xyl)}(μ‐CO)(CO)(Cp)2] (10), whereas 3e led to the formation of the five‐membered metallacycle [Fe(Cp)(CO){C{N(Me)(Xyl)}C(CO2Me)C(CO2Me)S}] (11) together with the diiron complex [Fe2{μ‐η1:η3‐C(CO2Me)=C(S)C=N(Me)(Xyl)}(μ‐CO)(CO)(Cp)2] (12). The formation of 10 and 12 implies C–H and C–C cleavage, respectively, and C–S bond formation without rupture of the diiron framework. The vinyliminium complexes 3a–d and also [Fe2{μ‐η1:η3‐C(Et)C(Et)CN(Me)(CH2Ph)}(μ‐CO)(CO)(Cp)2][SO3CF3] (3f) reacted with gray selenium in the presence of tBuLi to afford the five‐membered metallacycles [Fe(Cp)(CO){C{N(Me)R}C(R′)C(R′)Se}] (R = R′ = Me, 13a; R = Me, R′ = CO2Me, 13b; R = Me, R′ = Ph, 13c; R = Xyl, R′ = Me, 13d; R = CH2Ph, R′ = Et, 13f) in which one Se atom has been incorporated into the chelating ligand. The X‐ray molecular structures of 5a and 13a have been determined.
Syntheses and Solid‐State Structures of Bis(dialkylstibanyl)sulfanes and ‐telluranes
Authors: Heimann Stefan , Schulz Stephan , Bläser Dieter , Wölper Christoph
Published: August 2013

Distibines Sb2R4 (R = Me, Et) react with elemental chalcogens (E = S, Se, Te) with insertion into the Sb–Sb bond and formation of the corresponding bis(dialkylstibanyl)sulfanes, ‐selenanes, and ‐telluranes (R2Sb)2E. The structures of (Et2Sb)2S (1), (Et2Sb)2Te (3), and (Me2Sb)2Te (4) were determined by single‐crystal X‐ray diffraction. The complexes either adopt a syn–syn (1, 4) or syn–anti conformation (3) in the solid state. In addition, the compounds have different intermolecular interaction modes, which depend on the bridging chalcogen and the organic substituent bound to the Sb atoms.
Intercomparability of isotropic and anisotropic solar radiation models for different climatic zones of India
Authors: Karakoti Indira , Das Prasun Kumar
Published: August 2013

In present communication, a methodology is described to compute total radiation falling on inclined plane by employing the measured global and diffuse radiation data on horizontal surface of India. Five stations Jodhpur, Kolkata, Bangalore, New Delhi, and Srinagar representative of five different climatic zones—hot and dry, hot and humid, temperate, composite and cold, respectively are chosen for the study.

The measured data of 15 years (from 1986 to 2000) are exploited and statistical analysis is carried out for the monthly mean daily data. Isotropic model of Liu and Jordan and anisotropic model of Hay are applied in the estimation of total radiation on tilted plane facing south with various slopes and an inter‐comparison between these two models is made to ensure their adaptability in different climatic regions of India. Four tilt angles viz. latitude, latitude +15°N, latitude‐15°N and 22.5°N are considered and both the models are used for computation of total radiation to test whether variation in tilt angles affect the reliability of models for any particular climatic zone.

Furthermore, for realistic predictions, accuracy of isotropic and anisotropic models is tested through three statistical parameters and isotropic model is found fit for first four climatic zones of India while for cold region, performance of anisotropic seems better. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 925–932, 2014
Rational Krylov approximation of matrix functions: Numerical methods and optimal pole selection
Authors: Güttel Stefan
Published: August 2013

Matrix functions are a central topic of linear algebra, and problems of their numerical approximation appear increasingly often in scientific computing. We review various rational Krylov methods for the computation of large‐scale matrix functions. Emphasis is put on the rational Arnoldi method and variants thereof, namely, the extended Krylov subspace method and the shift‐and‐invert Arnoldi method, but we also discuss the nonorthogonal generalized Leja point (or PAIN) method. The issue of optimal pole selection for rational Krylov methods applied for approximating the resolvent and exponential function, and functions of Markov type, is treated in some detail. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Interplay between discretization and algebraic computation in adaptive numerical solutionof elliptic PDE problems
Authors: Arioli Mario , Liesen Jörg , Miçdlar Agnieszka , Strakoš Zdeněk
Published: August 2013

The Adaptive Finite Element Method (AFEM) for approximating solutions of PDE boundary value and eigenvalue problems is a numerical scheme that automatically and iteratively adapts the finite element space until a sufficiently accurate approximate solution is found. The adaptation process is based on a posteriori error estimators, and at each step of this process an algebraic problem (linear or nonlinear algebraic system or eigenvalue problem) has to be solved. In practical computations the solution of the algebraic problem cannot be obtained exactly. As a consequence, the algebraic error should be incorporated in the context of the AFEM and its a posteriori error estimators. The goal of this paper is to survey some existing approaches in the AFEM context that consider the interplay between the finite element discretization and the algebraic computation. We believe that a better understanding of this interplay is of great importance for the future development in the area of numerically solving large‐scale real‐world motivated problems. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Predictors of suicidal ideation in older individuals receiving home‐care services
Authors: Park Jong‐Il , Han Myeong‐il , Kim Myung Sig , Yoon Myeong‐Sook , Ko Sung‐Hee , Cho Hye‐Chung , Chung Young‐Chul
Published: August 2013

Objectives

Despite the importance of tending to older individuals who are vulnerable to suicide, little is known about suicidal ideation in the portion of this population receiving home‐care services in Asian countries. The objective of this cross‐sectional study was to examine predictors of suicidal ideation in older individuals using home‐care service.

Method

Participants were randomly selected from the individuals 50 years old and over using home‐care services across Jeollabuk‐do Province, Korea. A total of 697 subjects participated in this study. Each participant completed the short version of the Geriatric Depression Scale, the Scale for Suicidal Ideation, the Multidimensional Scale of Perceived Social Support, and the World Health Organization Disability Assessment Schedule II.

Results

Hierarchical regression analyses revealed that depression, perceived social support, and disability were significant predictors of suicidal ideation, whereas the roles of subjective health status and fish consumption remained ambiguous in this regard. In terms of social support, we also found that less perceived social support from family members was related to higher levels of suicidal ideation. The associations between various categories of disability and suicidal ideation disappeared after controlling for depression. Our investigation of the mediating effect of depression on the relationship between disability and suicidal ideation revealed that depression was either a complete (disability related to cognition, self‐care, getting along with others, and life activities) or partial (disability related to participation) mediator.

Conclusions

Preventive strategies focusing on depression, social support, and disability should be emphasized during encounters with older people receiving home‐care services. Copyright © 2013 John Wiley & Sons, Ltd.
Plutonium‐238 observations as a test of modeled transport and surface deposition of meteoric smoke particles
Authors: Dhomse S. S. , Saunders R. W. , Tian W. , Chipperfield M. P. , Plane J. M. C.
Published: August 2013

There are large uncertainties in the transport and surface deposition of upper atmospheric particles used to construct climate proxies. Here we use a 3‐D chemistry‐climate model (CCM) to simulate the transport and deposition of plutonium‐238 oxide nanoparticles formed after the ablation of a power unit in the upper stratosphere (~11°S) in 1964. The model reproduces both the observed hemispheric asymmetry and time scale of Pu‐238 deposition. We then use the CCM to investigate the transport of meteoric smoke particles (MSPs) from the upper mesosphere. The strongest MSP deposition is predicted to occur at middle latitudes, providing a significant source of Fe fertilization to the Southern Ocean. The model also predicts substantially more deposition in Greenland than in Antarctica (by a factor of ~15, in agreement with ice core measurements), showing that climate proxy measurements from a limited number of sites must be interpreted with care.
Development of probability distributions for urban hydrologic model parameters and a Monte Carlo analysis of model sensitivity
Authors: Knighton James , White Eric , Lennon Edward , Rajan Rajesh
Published: August 2013

This paper proposes an approach to estimating the uncertainty related to EPA Storm Water Management Model model parameters, percentage routed (PR) and saturated hydraulic conductivity (Ksat), which are used to calculate stormwater runoff volumes. The methodology proposed in this paper addresses uncertainty through the development of probability distributions for urban hydrologic parameters through extensive calibration to observed flow data in the Philadelphia collection system. The established probability distributions are then applied to the Philadelphia Southeast district model through a Monte Carlo approach to estimate the uncertainty in prediction of combined sewer overflow volumes as related to hydrologic model parameter estimation.

Understanding urban hydrology is critical to defining urban water resource problems. A variety of land use types within Philadelphia coupled with a history of cut and fill have resulted in a patchwork of urban fill and native soils. The complexity of urban hydrology can make model parameter estimation and defining model uncertainty a difficult task. The development of probability distributions for hydrologic parameters applied through Monte Carlo simulations provided a significant improvement in estimating model uncertainty over traditional model sensitivity analysis. Copyright © 2013 John Wiley & Sons, Ltd.
Hydrochemical variability during flood events within a small forested catchment in Basque Country (Northern Spain)
Authors: Martínez‐Santos M. , Antigüedad I. , Ruiz‐Romera E.
Published: August 2013

Understanding runoff processes is critical to issues of water quality. Therefore, the main purpose of this paper is to test a methodology that can be used when continuous electrical conductivity (EC) data are recorded in a single control point and no more data are available along the catchment. Although both non‐tracer‐based and tracer‐based techniques have been used for two‐component hydrograph separation, EC‐based method proved to be more suitable to gain further insight into the runoff generation and can help clarifying water sources and flowpaths to the river. So the use of EC has allowed the separation of pre‐event (Qp) and event (Qe) water contribution in different types of flood events, the assessment of temporal behaviour of related elements and the calculation of Qp/Qe ratio and regression equations. However, the weaker correlations of some elements with discharge and with this ratio lead us to admit the existence of at least one third component of flow, which is characterized by dissolved organic carbon, SO42− and Cl−. This component presumably comes from a far‐stream source and through a subsurface flow and is the key for advancing in new findings on the catchment hydrology. Copyright © 2013 John Wiley & Sons, Ltd.
Modeling the effects of climate change projections on streamflow in the Nooksack River basin, Northwest Washington
Authors: Dickerson‐Lange Susan E. , Mitchell Robert
Published: August 2013

The Nooksack River has its headwaters in the North Cascade Mountains and drains an approximately 2000 km2 watershed in northwestern Washington State. The timing and magnitude of streamflow in a snowpack‐dominated drainage basin such as the Nooksack River basin are strongly influenced by temperature and precipitation. Projections of future climate made by general circulation models (GCMs) indicate increases in temperature and variable changes in precipitation for the Nooksack River basin. Understanding the response of the river to climate change is crucial for regional water resources planning because municipalities, tribes, and industry depend on the river for water use and for fish habitat.

We combine three different climate scenarios downscaled from GCMs and the Distributed‐Hydrology‐Soil‐Vegetation Model to simulate future changes to timing and magnitude of streamflow in the higher elevations of the Nooksack River. Simulations of future streamflow and snowpack in the basin project a range of magnitudes, which reflects the variable meteorological changes indicated by the three GCM scenarios and the local natural variability employed in the modeling. Simulation results project increased winter flows, decreased summer flows, decreased snowpack, and a shift in timing of the spring melt peak and maximum snow water equivalent. These results are consistent with previous regional studies, but the magnitude of increased winter flows and total annual runoff is higher. Increases in temperature dominate snowpack declines and changes to spring and summer streamflow, whereas a combination of increases in temperature and precipitation control increased winter streamflow. Copyright © 2013 John Wiley & Sons, Ltd.
Understanding the impacts of allocation approaches during process-based life cycle assessment of water treatment chemicals
Authors: Alvarez-Gaitan Juan P , Peters Gregory M , Short Michael D , Schulz Matthias , Moore Stephen
Published: August 2013

Chemicals are an important component of advanced water treatment operations not only in terms of economics but also from an environmental standpoint. Tools such as life cycle assessment (LCA) are useful for estimating the environmental impacts of water treatment operations. At the same time, LCA analysts must manage several fundamental and as yet unresolved methodological challenges, one of which is the question of how best to “allocate” environmental burdens in multifunctional processes. Using water treatment chemicals as a case study example, this article aims to quantify the variability in greenhouse gas emissions estimates stemming from methodological choices made in respect of allocation during LCA. The chemicals investigated and reported here are those most important to coagulation and disinfection processes, and the outcomes are illustrated on the basis of treating 1000 ML of noncoagulated and nondisinfected water. Recent process and economic data for the production of these chemicals is used and methodological alternatives for solving the multifunctionality problem, including system expansion and mass, exergy, and economic allocation, are applied to data from chlor-alkali plants. In addition, Monte Carlo simulation is included to provide a comprehensive picture of the robustness of economic allocation results to changes in the market price of these industrial commodities. For disinfection, results demonstrate that chlorine gas has a lower global warming potential (GWP) than sodium hypochlorite regardless of the technique used to solve allocation issues. For coagulation, when mass or economic allocation is used to solve the multifunctionality problem in the chlor-alkali facility, ferric chloride was found to have a higher GWP than aluminum sulfate and a slightly lower burden where system expansion or exergy allocation are applied instead. Monte Carlo results demonstrate that when economic allocation is used, GWP results were relatively robust and resilient to the changes in commodity prices encountered during the study period, with standard deviations less than 6% for all chlor-alkali-produced chemicals reported here. Overall outcomes from the study demonstrate the potential variability in LCA results according to the allocation approach taken and emphasize the need for a consensus approach to water sector LCAs. Integr Environ Assess Manag 2013;X:000–000. © 2013 SETAC Integr Environ Assess Manag 2014;10:87–94. © 2013 SETAC
FACTORS CONTROLLING WATER DELIVERY BY PITCHER IRRIGATION
Authors: Vasudevan Padma , Thapliyal Alka , Tandon Mamta , Dastidar M. G. , Sen P. K.
Published: August 2013

Pitcher irrigation is particularly useful for horticulture in arid zones. It is of interest to see the correlation of water flow (WF) through the pitcher wall into air, water, and soil with the moisture deficit in air (MD). The pattern of WF into the three media was studied for four pitchers filled with water up to the neck, under natural atmospheric conditions and under hydraulic head (HH). WF without HH was in the order air > soil > water, the amount being negligible in water. WF under HH was also in the same order, but with a significant increase in WF. In all cases WF correlated linearly to level of dryness of the air. Hydraulic conductivity (Ks) for all the pitchers also varied in the order air > soil > water. Ks in water was independent of MD, whereas Ks in soil and air increased with MD. Thus total WF through capillary pores of the pot is due to pressure of hydraulic head only when WF is into the water medium. In air and soil there is an additional WF due to the MD in the medium. This is seen as a negative pressure or an equivalent negative hydraulic head. Copyright © 2013 John Wiley & Sons, Ltd.