bluuebunny/crossref_metadata_2025 huggingface dataset:
Palladium on Carbon: An Efficient, Heterogeneous and Reusable Catalytic System for Carbonylative Synthesis of N‐Substituted Phthalimides
Authors: Khedkar Mayur V. , Khan Shoeb R. , Sawant Dinesh N. , Bagal Dattatraya B. , Bhanage Bhalchandra M.
Published: December 2011

The application of palladium on carbon (Pd/C) as a heterogeneous recyclable catalyst was investigated for the double carbonylation of o‐dihaloarenes with amines providing excellent yield of N‐substituted phthalimides in shorter reaction time as compared to earlier reported homogeneous protocols. Furthermore, the scope of the developed protocol was applied for the synthesis N‐substituted phthalimides from o‐halobenzoates and o‐halobenzoic acid via a single step carbonylative cyclization reaction. The developed methodology describes an efficient one‐step approach for the synthesis of an important class of heterocycles and tolerates a wide variety of functional groups. It circumvents the use of phosphine ligands with an additional advantage of catalyst recyclability for up to eight consecutive cycles.
Metal‐Free, Radical Addition to Alkenes via Desulfitative Chlorine Atom Transfer
Authors: Cao Lidong , Weidner Karin , Renaud Philippe
Published: December 2011

An efficient method for radical additions to unactivated alkenes via desulfitative chlorine‐atom transfer is described. The reaction is based on the use of readily available sulfonyl chlorides as starting materials and cheap radical initiators such as azobisisobutyronitrile (AIBN), di‐tert‐butyldiazene (DTBD), and dilauroyl peroxide (DLP). No transition metal catalyst is required and the reaction takes place under mild conditions at temperatures ≤85 °C.
Gold versus Silver‐Catalyzed Intermolecular Hydroaminations of Alkenes and Dienes
Authors: Giner Xavier , Nájera Carmen , Kovács Gábor , Lledós Agustí , Ujaque Gregori
Published: December 2011

Comparative studies about the hydroamination of unactivated alkenes and dienes catalyzed by either cationic gold(I) triphenyl phosphite complexes or silver salts were performed using sulfonamides, anilines and carbamates as nucleophiles. Gold‐catalyzed reactions generally, need lower loadings than those carried out with silver salts. Simple alkenes react only with sulfonamides and weak aromatic amines such as p‐nitroaniline, whereas for conjugated dienes carbamates can also be used. Carbon‐carbon double bond isomerization is observed only with gold similarly to when triflic acid was used, affording mixtures of regioisomeric products in the same cases. Silver‐catalyzed hydroaminations failed with terminal alkenes, except with styrenes. Conjugate dienes can be hydroaminated either at 85 °C in toluene or at room temperature in dichloromethane. Non‐conjugated 1,4‐ and 1,5‐dienes suffer double hydroamination leading to saturated N‐tosylated heterocyclic amines The catalytic cycle for the silver(I)‐catalyzed hydroamination process has been computationally analyzed, resembling gold(I)‐catalyzed processes, although with some significant differences.
An Alternative to Nitromethane as Solvent: The Promoting Influence of Nitro‐Functionalized Imidazolium Salts for Synthesis and Catalysis
Authors: Ren Yajun , Li Minghao , Yang Jie , Peng Jiajian , Gu Yanlong
Published: December 2011

Nitromethane, a volatile and toxic organic compound, is commonly used as solvent for organic and catalytic reactions. In order to find an alternative for this specific nitro‐containing organic solvent, the performance of some nitro‐functionalized imidazolium salts such as 1‐methyl‐3‐(4‐nitrobenzyl)imidazolium hexafluorophosphate, 1‐methyl‐3‐(4‐nitrobenzyl)imidazolium tetrafluoroborate, 1‐methyl‐3‐(4‐nitrobenzyl)imidazolium bis(trifluoromethanesulfonyl)amide and 1,2‐dimethyl‐3‐(4‐ nitrobenzyl)imidazolium hexafluorophosphate, was examined in some reactions including trimethylsilylation of alcohols with hexamethyldisilazane, ring‐opening reactions of 2‐aryl‐3,4‐dihydropyrans with thiophenols or thiols, and a copper‐ mediated oxidative coupling of alkynes. As expected, these imidazolium salts can indeed replace nitromethane in these reactions. Particularly, the imidazolium salt along with the metal catalyst, if involved, can be easily recovered and reused without significant loss of activity. The use of these nitro‐functionalized imidazolium salts as alternative solvents for nitromethane not only confers a green aspect to the reaction system, but also facilitates a rational design of a catalytic system with the concept of green chemistry.
Interspecies scaling: prediction of human biliary clearance and comparison with QSPKR
Authors: Morris Marilyn E. , Yang Xinning , Gandhi Yash A. , Bhansali Suraj G. , Benincosa Lisa J.
Published: December 2011

The aim of this study was to evaluate the prediction performance of various allometric scaling methods in predicting human biliary clearance (CLb) from data in rats or multiple animal species and to compare the prediction performance with that of quantitative structure pharmacokinetic relationship (QSPKR) models. CLb data of parent drugs in rats and humans were collected from the literature for 18 compounds. A simple allometric approach was applied to CLb or unbound CLb using 0.75 or 0.66 as the allometric exponent. For scaling from rat studies alone, the prediction using 0.66 as the exponent was better than that using 0.75, and a better prediction was obtained for unbound CLb than CLb. For a subset of compounds, six multiple‐species scaling methods were compared, with the best prediction achieved with the simple unbound CLb approach. However, in the absence of protein binding data, the correction with maximum life‐span potential (MLP) or ‘Rule of exponent’ (ROE) method offered the best prediction. Overall, multiple species had better predictability than scaling with the rat alone. Comparison of predicted human CLb values using multiple animal species and QSPKR offered similar prediction performance. In conclusion, the results of the present study, although based on limited data, suggested that the prediction for human CLb by allometry was greatly improved by the incorporation of protein binding. Human CLb prediction using rat data alone was not satisfactory. Additionally, QSPKR provides an alternative approach to allometry for the prediction of human biliary clearance. Copyright © 2011 John Wiley & Sons, Ltd.
Size‐Determining Dependencies in Supramolecular Organometallic Host–Guest Chemistry
Authors: Schindler Andrea , Heindl Claudia , Balázs Gábor , Gröger Christian , Virovets Alexander V. , Peresypkina Eugenia V. , Scheer Manfred
Published: December 2011

Treatment of the pentaphosphaferrocene [Cp*Fe(η5‐P5)] with CuIhalides in the presence of different templates leads to novel fullerene‐like spherical molecules that serve as hosts for the templates. If ferrocene is used as the template the 80‐vertex ball [Cp2Fe]@[{Cp*Fe(η5‐P5)}12{CuCl}20] (4), with an overall icosahedral C80topological symmetry, is obtained. This result shows the ability of ferrocene to compete successfully with the internal template of the reaction system [Cp*Fe(η5‐P5)], although the 90‐vertex ball [{Cp*Fe(η5:η1:η1:η1:η1:η1‐P5)}12(CuCl)10(Cu2Cl3)5{Cu(CH3CN)2}5] (2 a) containing pentaphosphaferrocene as a guest is also formed as a byproduct. With use of the triple‐decker sandwich complex [(CpCr)2(μ,η5‐As5)] as a template the reaction between [Cp*Fe(η5‐P5)] and CuBr leads to the 90‐vertex ball [(CpCr)2(μ,η5‐As5)]@[{Cp*Fe(η5‐P5)}12{CuBr}10{Cu2Br3}5{Cu(CH3CN)2}5] (6), in which the complete molecule acts as a template. However, if the corresponding reaction is instead carried out with CuCl, cleavage of the triple‐decker complex is found and the 80‐vertex ball [CpCr(η5‐As5)]@[{Cp*Fe(η5‐P5)}12{CuCl}20] (5) is obtained. This accommodates as its guest [CpCr(η5‐As5)], which has only 16 valence electrons in a triplet ground state and is not known as a free molecule. The triple‐decker sandwich complex [(CpCr)2(μ,η5‐As5)] requires 53.1 kcal mol−1to undergo cleavage (as calculated by DFT methods) and therefore this reaction is clearly endothermic. All new products have been characterized by single‐crystal X‐ray crystallography. A favoured orientation of the guest molecules inside the host cages has been identified, which shows π⋅⋅⋅π stacking of the five‐membered rings (Cp andcyclo‐As5) of the guests and thecyclo‐P5rings of the nanoballs of the hosts.
Elucidation of the Structure–Activity Relationships of Apelin: Influence of Unnatural Amino Acids on Binding, Signaling, and Plasma Stability
Authors: Murza Alexandre , Parent Alexandre , Besserer‐Offroy Elie , Tremblay Hugo , Karadereye Félix , Beaudet Nicolas , Leduc Richard , Sarret Philippe , Marsault Éric
Published: December 2011

Apelin is the endogenous ligand of the APJ receptor, a member of the G‐protein‐coupled receptor family. The apelin–APJ complex has been detected in many tissues and is emerging as a promising target for several pathophysiological conditions. There is currently little information on the structure–activity relationship (SAR) of the apelin hormone. In an effort to better delineate SAR, we synthesized analogues of apelin‐13 modified at selected positions with unnatural amino acids, with a particular emphasis on the C‐terminal portion. Analogues were then tested in binding and functional assays by evaluating Gi/o‐mediated decreases in cAMP levels and by assessing β‐arrestin2 recruitment to the APJ receptor. The plasma stability of new compounds was also assessed. Several analogues were found to possess increased binding and higher stability than the parent peptide.
Clinical outcomes of oncologic gastrointestinal resections in patients with cirrhosis
Authors: Artinyan Avo , Marshall Christy L. , Balentine Courtney J. , Albo Daniel , Orcutt Sonia T. , Awad Samir S. , Berger David H. , Anaya Daniel A.
Published: December 2011

BACKGROUND:

Cirrhosis is a risk factor for postoperative morbidity and mortality after general surgical procedures. However, the impact of cirrhosis on outcomes of surgical resection for gastrointestinal (GI) malignancies has not been described. The authors' objective was to characterize early postoperative and transitional outcomes in cirrhotic patients undergoing GI cancer surgery.

METHODS:

Query of the National Inpatient Sample Database (2005‐2008) identified 106,729 patients who underwent resection for GI malignancy; 1479 (1.4%) had cirrhosis. The association of cirrhosis with postoperative outcomes was examined. The primary outcome measure was in‐hospital mortality. Secondary outcomes included length‐of‐stay (LOS) and discharge to long‐term care facility (LTCF).

RESULTS:

Cirrhotic patients had higher risk of in‐hospital mortality (8.9% vs 2.8%, P < .001), longer LOS (11.5 ± 0.26 vs 10.0 ± 0.03 days, P < .001), and higher rate of discharge to LTCF (19.0% vs 15.7%, P < .001). Mortality was highest in patients with moderate to severe liver dysfunction (21.5% vs 6.5%, P < .001). On multivariate analysis, cirrhosis was an independent predictor of in‐hospital mortality (odds ratio [OR], 3.0; 95% confidence interval [CI] 2.5‐3.7) and nonhome discharge (OR, 1.7; 95% CI, 1.4‐2.0). In cirrhotic patients, moderate to severe liver dysfunction was the only independent predictor of in‐hospital mortality (OR, 4.03; 95% CI, 2.7‐5.9), but did not predict discharge disposition.

CONCLUSIONS:

Resection of GI malignancy in cirrhotics is associated with poor early postoperative and transitional outcomes, with severity of liver disease being the primary determinant of postoperative mortality. These data suggest that GI cancer operations can be performed safely in well‐selected cirrhotic patients with mild liver dysfunction. Cancer 2012;3494–3500. © 2011 American Cancer Society.
Hypofractionated stereotactic body radiotherapy in low‐risk prostate adenocarcinoma
Authors: McBride Sean M. , Wong Douglas S. , Dombrowski John J. , Harkins Bonnie , Tapella Patricia , Hanscom Heather N. , Collins Sean P. , Kaplan Irving D.
Published: December 2011

BACKGROUND:

Recent reports using extreme hypofractionated regimens in the treatment of low‐risk prostate adenocarcinoma have been encouraging. Here, the authors report on their own multi‐institutional experience with extreme hypofractionated stereotactic radiotherapy for early stage disease.

METHODS:

In total, at 4 centers, 45 patients with National Comprehensive Cancer Network‐defined, low‐risk prostate adenocarcinoma were enrolled in a phase 1, multi‐institutional trial of hypofractionated radiosurgery with a proprietary radiosurgical device (CyberKnife). Thirty‐four patients received 7.5 grays (Gy) delivered in 5 fractions, 9 patients received 7.25 Gy delivered in 5 fractions, and 2 patients received other regimens. The variables evaluated were biochemical progression‐free survival (bPFS), prostate‐specific antigen (PSA) bounce, and toxicities. Health‐related quality of life was evaluated using the Sexual Health Inventory for Men (SHIM), American Urological Association (AUA), and Expanded Prostate Cancer Index Composite (EPIC) questionnaires.

RESULTS:

The median follow‐up for surviving patients was 44.5 months (range, 0‐62 months). The bPFS rate at 3 years was 97.7%. The median PSA declined from 4.9 ng/mL at diagnosis to 0.2 ng/mL at last follow‐up, and the median percentage PSA decline at 12 months was 80%. Nine patients experienced at least 1 PSA bounce ≥0.4 ng/mL, and 4 patients experienced 2 PSA bounces. The median time to first PSA bounce was 11.6 months (range, 7.2‐18.2 months), and the mean percentage PSA bounce was 1.07 ng/mL. There was 1 episode of late grade 3 urinary obstruction, and there were 2 episodes of late grade 3 proctitis. There was a significant late decline in SHIM and EPIC sexual scores and a small, late decline in the EPIC Bowel domain score.

CONCLUSIONS:

In a select population, extreme hypofractionation with stereotactic radiosurgery was safe and effective for the treatment of low‐risk prostate adenocarcinoma. Cancer 2012. © 2011 American Cancer Society.
Sequential Continuous Flow Processes for the Oxidation of Amines and Azides by using HOF⋅MeCN
Authors: McPake Christopher B. , Murray Christopher B. , Sandford Graham
Published: December 2011

The generation and use of the highly potent oxidising agent HOF⋅MeCN in a controlled single continuous flow process is described. Oxidations of amines and azides to corresponding nitrated systems by using fluorine gas, water and acetonitrile by sequential gas–liquid/liquid–liquid continuous flow procedures are reported.
Automated identification of circulating tumor cells by image cytometry
Authors: Scholtens Tycho M. , Schreuder Frederik , Ligthart Sjoerd T. , Swennenhuis Joost F. , Greve Jan , Terstappen Leon W. M. M.
Published: December 2011

Presence of circulating tumor cells (CTC), as detected by the CellSearch® System, in patients with metastatic carcinomas is associated with poor survival prospects. CellTracks TDI, a dedicated image cytometer, was developed to improve the enumeration of these rare CTC. The CellSearch System was used to enumerate CTC in 7.5 mL blood of 68 patients with cancer and 9 healthy controls. Cartridges containing the fluorescently labeled CTC from this system were reanalyzed using the image cytometer, which acquires images with a TDI camera using a 40×/0.6 NA objective and lasers as light source. Automated classification of events was performed by the Random Forest method using Matlab. An automated classifier was developed to classify events into CTC, apoptotic CTC, CTC debris, leukocytes, and debris not related to CTC. A high agreement in classification was obtained between the automated classifier and five expert reviewers. Comparison of images from the same events in CellTracks TDI and CellTracks Analyzer II shows improved resolution in fluorescence images and improved classification by adding bright‐field images. Improved detection efficiency for CD45‐APC avoids the classification of leukocytes nonspecifically binding to cytokeratin as CTC. The correlation between number of CTC detected in CellTracks TDI and CellTracks Analyzer II is good with a slope of 1.88 and a correlation coefficient of 0.87. Automated classification of events by CellTracks TDI eliminates the operator error in classification of events as CTC and permits quantitative assessment of parameters. The clinical relevance of various CTC definitions can now be investigated. © 2011 International Society for Advancement of Cytometry
Identification of a cross‐reacting, monoclonal anti‐human CD233 antibody for identification and sorting of rhesus macaque erythrocytes
Authors: Byrnes Colleen , Terry Lee Y. , Donahue Robert E. , Miller Jeffery L.
Published: December 2011

Erythroid biology research involving rhesus macaques has been applied to several topics including malaria, hemoglobinopathy and gene therapy research. However, analyses of the rhesus red blood cells are limited by the inability to identify and sort those cells in research blood samples using flow cytometry. Here it is reported that the BRIC 6 hybridoma clone raised to the human erythroid surface molecule (referred to as CD233, Band 3, AE1, or SLC4A1) produces cross‐reactive and erythroid‐specific antibodies for flow cytometric detection and sorting of rhesus macaque erythrocytes. © 2011 International Society for Advancement of Cytometry
Conventional disease‐modifying antirheumatic drugs to treat rheumatoid arthritis
Authors: Rath T. , Sander O. , Rubbert A.
Published: December 2011

Rheumatoid arthritis (RA) is characterized by a symmetric polyarthritis of unknown etiology that, if untreated or unresponsive to therapy, typically leads to deformities and destruction of joints through the erosion of cartilage and bone. Currently available disease‐modifying antirheumatic drugs (DMARDs) can control synovitis and may slow, or even stop, radiographic progression, improve function and quality of life, and normalize mortality rates. This review gives a brief overview on commonly used conventional DMARDs and their role in the current management of RA. Methotrexate is still considered the gold standard among the DMARDs, and is widely accepted as first‐line treatment in the management of RA. Other DMARDs are less frequently used in monotherapy or as first‐line agents but continue to have a role as antirheumatic agents in select patients. DMARD combination therapy may still represent a valuable therapeutic option in patients who fail to DMARD monotherapy or in whom combination therapy is considered initially. This review will focus on a better understanding of the critical importance of early DMARD treatment, the goal of remission and the need for tight control and adaptive modification in case of inadequate response or intolerance. Drug Dev Res 72:657–663, 2011. © 2011 Wiley Periodicals, Inc.
Bosentan treatment of digital ulcers related to autoimmune disorders
Authors: Cantisani Carmen , Mattozzi Carlo , Giancristoforo Simona , D'Epiro Sara , Richetta Antonio G.
Published: December 2011

Endothelin 1, a powerful endogenous vasoconstrictor and mitogen, may be causal to pulmonary hypertension. Evidence also suggests that endothelin (ET) may have a fundamental role in scleroderma pathogenesis, including pulmonary arterial hypertension (PAH), a leading cause of death in patients with scleroderma. The development of a new class of drug, ET receptor antagonists, provides an improved outlook for patients with scleroderma and related diseases. Increasing vigilance toward early detection of PAH in scleroderma and a multidisciplinary approach to diagnosis and treatment may improve the clinical outcome for these patients. We describe the efficacy and safety of bosentan, an orally active dual ET‐receptor antagonist, in patients with digital ulcers. Bosentan increases exercise capacity and improves hemodynamics in patients with pulmonary hypertension, suggesting that ET has an important role in pulmonary hypertension but in our experience also for refractory skin ulcers. Drug Dev Res 72:750–755, 2011. © 2011 Wiley Periodicals, Inc.
Beyond transitional selection: New roles for BLyS in peripheral tolerance
Authors: Oropallo Michael A. , Kiefer Kerstin , Marshak‐Rothstein Ann , Cancro Michael P.
Published: December 2011

B‐cell targeted therapies have enjoyed recent success in the treatment of systemic autoimmune diseases. Among these, Belimumab, which blocks the B‐cell survival cytokine BLyS, was recently approved for the treatment of systemic lupus erythematosus. It is therefore important to consider the roles BLyS plays in B‐cell tolerance. Herein, we review how BLyS contributes to the negative selection of autoreactive B‐cell clones from the preimmune repertoire as well as its role in regulating both germinal center and extrafollicular peripheral B‐cell responses. We further examine the complex role of Toll‐like receptors (TLRs) in humoral autoimmunity, pointing out potential crosstalk between BLyS and TLR pathways. Drug Dev Res 72:779–787, 2011. © 2011 Wiley Periodicals, Inc.
Expression of nitrous oxide reductase from Pseudomonas stutzeri in transgenic tobacco roots using the root‐specific rolD promoter from Agrobacterium rhizogenes
Authors: Wan Shen , Johnson Amanda M. , Altosaar Illimar
Published: December 2011

The nitrous oxide (N2O) reduction pathway from a soil bacterium, Pseudomonas stutzeri, was engineered in plants to reduce N2O emissions. As a proof of principle, transgenic plants expressing nitrous oxide reductase (N2OR) from P. stutzeri, encoded by the nosZ gene, and other transgenic plants expressing N2OR along with the more complete operon from P. stutzeri, encoded by nosFLZDY, were generated. Gene constructs were engineered under the control of a root‐specific promoter and with a secretion signal peptide. Expression and rhizosecretion of the transgene protein were achieved, and N2OR from transgenic Nicotiana tabacum proved functional using the methyl viologen assay. Transgenic plant line 1.10 showed the highest specific activity of 16.7 µmol N2O reduced min−1 g−1 root protein. Another event, plant line 1.9, also demonstrated high specific activity of N2OR, 13.2 µmol N2O reduced min−1 g−1 root protein. The availability now of these transgenic seed stocks may enable canopy studies in field test plots to monitor whole rhizosphere N flux. By incorporating one bacterial gene into genetically modified organism (GMO) crops (e.g., cotton, corn, and soybean) in this way, it may be possible to reduce the atmospheric concentration of N2O that has continued to increase linearly (about 0.26% year−1) over the past half‐century.
Role of recent and old riverine barriers in fine‐scale population genetic structure of Geoffroy's tamarin (Saguinus geoffroyi) in the Panama Canal watershed
Authors: Díaz‐Muñoz Samuel L.
Published: December 2011

The role of physical barriers in promoting population divergence and genetic structuring is well known. While it is well established that animals can show genetic structuring at small spatial scales, less well‐resolved is how the timing of the appearance of barriers affects population structure. This study uses the Panama Canal watershed as a test of the effects of old and recent riverine barriers in creating population structure in Saguinus geoffroyi, a small cooperatively breeding Neotropical primate. Mitochondrial sequences and microsatellite genotypes from three sampling localities revealed genetic structure across the Chagres River and the Panama Canal, suggesting that both waterways act as barriers to gene flow. F‐statistics and exact tests of population differentiation suggest population structure on either side of both riverine barriers. Genetic differentiation across the Canal, however, was less than observed across the Chagres. Accordingly, Bayesian clustering algorithms detected between two and three populations, with localities across the older Chagres River always assigned as distinct populations. While conclusions represent a preliminary assessment of genetic structure of S. geoffroyi, this study adds to the evidence indicating that riverine barriers create genetic structure across a wide variety of taxa in the Panama Canal watershed and highlights the potential of this study area for discerning modern from historical influences on observed patterns of population genetic structure.
TiIV Complexes of Redox‐Active Schiff Bases
Authors: Donzelli Alberto , Potvin Pierre G.
Published: December 2011

Isopropoxy‐ and tert‐butoxy‐(salicylideneamino‐2‐thiophenolato)titanium(IV) complexes from seven different salicylaldehydes were prepared and characterized. Two examples,diisopropoxy(4′‐methoxysalicylideneamino‐2‐thiophenolato)titanium(IV) and di‐tert‐butoxy(salicylideneamino‐2‐thiophenolato)titanium(IV), were also characterized crystallographically. Three other examples crystallized as L2Ti species, one of which was an unusual dinuclear complex in which the ligands had dimerized through S–S interactions and formed amino linkages in an unexpected redox exchange. In all cases, cyclic voltammetry in CH2Cl2 showed irreversible oxidations at +1.2–1.4 V vs. Ag/AgCl. 2‐Propanol induced a cathodic shift of the first oxidation potentials without apparent decomposition.
MOFs for Use in Adsorption Heat Pump Processes
Authors: Henninger Stefan K. , Jeremias Felix , Kummer Harry , Janiak Christoph
Published: December 2011

Thermally driven heat pumps can significantly help to minimize primary energy consumption and greenhouse gas emissions generated by industrial or domestic heating and cooling processes. This is achieved by using solar or waste heat as the operating energy rather than electricity or fossil fuels. One of the most promising technologies in this context is based on the evaporation and consecutive adsorption of coolant liquids, preferably water, under specific conditions. The efficiency of this process is first and foremost governed by the microporosity, hydrophilicity, and hydrothermal stability of the sorption material employed. Traditionally, inorganic porous substances like silica gel, aluminophosphates, or zeolites have been investigated for this purpose. However, metal–organic frameworks (MOFs) are emerging as the newest and by far the most capable class of microporous materials in terms of internal surface area and micropore volume as well as structural and chemical variability. With further exploration of hydrothermally stable MOFs, a large step forward in the field of sorption heat pumps is anticipated. In this work, an overview of the current investigations, developments, and possibilities of MOFs for use in heat pumps is given.
Ruthenium Hydride Complexes with Zwitterionic Quinonoid Ligands – Isomer Separation, Structural Properties, Electrochemistry, and Catalysis
Authors: Hohloch Stephan , Braunstein Pierre , Sarkar Biprajit
Published: December 2011

Reactions of [Ru(PPh3)3(CO)(H)Cl] with the zwitterionic p‐benzoquinonemonoimine‐type ligands 4‐(n‐butylamino)‐6‐(n‐butylimino)‐3‐oxocyclohexa‐1,4‐dien‐1‐olate (Q1), 4‐(isopropylamino)‐6‐(isopropylimino)‐3‐oxocyclohexa‐1,4‐dien‐1‐olate (Q2), and 4‐(benzylamino)‐6‐(benzylimino)‐3‐oxocyclohexa‐1,4‐dien‐1‐olate (Q3) in the presence of a base led to the formation of mononuclear complexes [Ru(PPh3)2(CO)(H)(Q1–H)] (1a and 1b), [Ru(PPh3)2(CO)(H)(Q2–H)] (2a and 2b), and [Ru(PPh3)2(CO)(H)(Q3–H)] (3a and 3b), respectively. The positional isomers (a and b) that were formed in each case were separated by preparative TLC. The structural characterization of 2a and 3a·MeCN helped to identify the isomers, and established the distorted octahedral coordination geometry around the ruthenium center. The bond lengths in the complexes are consistent with localization of the double bonds in Q2–H and Q3–H in both their monodeprotonated and metal‐coordinated forms. The Ru–C–O(carbonyl) bond angle is almost linear. Cyclic voltammetry of the complexes showed one oxidation and one reduction process. These are predominantly centered on the quinonoid ligands, which shows their redox‐noninnocent character. Studies of transfer hydrogenation with 2a as a precatalyst showed that, in the presence of KOH, acetophenone could be converted to 1‐phenylethanol within 10 h in over 90 % yield.
Determination of L‐Lactic Acid Content in Foods by Enzyme‐Based Amperometric Bioreactor
Authors: Bori Zsuzsanna , Csiffáry Gábor , Virág Diána , Tóth‐Markus Marianna , Kiss Attila , Adányi Nóra
Published: December 2011

A thermostable lactate oxidase (from Aerococcus viridans) based bioreactor was elaborated for L‐lactate determination in dairy products. The enzyme was immobilised in a thin‐layer enzyme cell connected into a flow injection system with an amperometric detector. The linear measuring range was 0.1–1 mmol/L L‐lactate (R2=0.99; linear regression equation: y=81.2x+3.3). The detection limit was 0.05 mmol/L. 40 Samples were analyzed per hour. Considering reproducibility: the signals measured were very stable for over 800 injections, after this period the activity of the cell decreased slowly. The method was used for the control of dairy products and for monitoring milk freshness.
Potentiometric Sensor Array for Analysis of Complex Rare Earth Mixtures
Authors: Kirsanov Dmitry , Khaydukova Maria , Tkachenko Lyudmila , Legin Andrey , Babain Vasily
Published: December 2011

An approach for simultaneous quantification of several rare earth elements (RE) in complex mixtures, using an array of cross‐sensitive potentiometric sensors with plasticized polymeric membranes, is reported. 14 different ligands suggested in liquid extraction systems for separation of lanthanides/actinides were employed as membrane active compounds in the polymeric sensors. The sensors of the array were found to have high potentiometric sensitivity towards lanthanide ions in acidic solutions with pH 1.5. The array of 28 sensors was applied for simultaneous determination of three RE metals in four sets of model mixtures simulating technological solutions of spent nuclear fuel reprocessing process. Multivariate calibration models calculated with PLS1 algorithm revealed that analysis of Y, La and Gd in mixtures with uranyl nitrate is possible with RMSEP values 0.29, 0.17 and 0.28 logCMe correspondingly (confirmed by independent test set). Determination of Nd, Sm and Gd in mixtures with uranyl (RMSEP=0.25–0.26 logCMe) and with thorium (RMSEP=0.28–0.37 logCMe) is also possible.
Application of F−‐Selective Ionophores in Carboxylated or Aminated Poly(Vinyl Chloride)‐Based Membranes of Ion‐Selective Electrodes
Authors: Pietrzak Mariusz , Mroczkiewicz Monika , Malinowska Elżbieta
Published: December 2011

In this work, complexes of Zr(IV) and Al(III) cations with tert‐butyl substituted tetraphenylporphyrin or tetraazaporphine were tested as F−‐selective ionophores in plasticized aminated or carboxylated PVC membranes of ion‐selective electrodes. It was found that functional groups present in the backbone of applied polymers influence the complexing properties of tested ligands, causing changes of F−‐selectivity of electrodes prepared with their use in comparison with the electrodes with unmodified PVC membranes. This work shows, that application of functionalized PVC can eliminate the need of relatively expensive ionic sites addition to ion‐selective membranes doped with metallocomplexes.
Impedimetric DNA Aptasensor for Sensitive Detection of Ochratoxin A in Food
Authors: Castillo Gabriela , Lamberti Ilaria , Mosiello Lucia , Hianik Tibor
Published: December 2011

We report a high sensitive biosensor based on DNA aptamers for detection of ochratoxin A (OTA). The thiolated DNA aptamers specific to OTA of different configurations have been immobilized by chemisorption to the surface of a gold electrode. Electrochemical impedance spectroscopy (EIS) in the presence of a redox probe [Fe(CN)6]−3/−4 has been used for the determination of the charge transfer resistance, Rct, followed by addition of OTA. The Rct increased with increasing OTA concentration in the range of 0.1–100 nM. The limit of detection (0.12–0.40 nM) depended on the configuration of the aptamers. The sensor was regenerable and validated in food samples with satisfactory recovery.
Towards Protein Assays on Paper Platforms with Potentiometric Detection
Authors: Szűcs Júlia , Gyurcsányi Róbert E.
Published: December 2011

Microfluidic paper‐based assays represent a new approach to address the need for simple and cost‐effective medical diagnostics. In an effort to couple paper‐based assays with a similarly simple signal transduction, here we explored the feasibility of using potentiometric detection as a new modality to quantify affinity assays performed on a paper platform. As proof of principle a dot‐blot model assay based on using IgE aptamer‐gold nanoparticle conjugates was developed for the quantitative determination of IgE. The gold nanoparticle conjugates further catalyzed the deposition of silver nanoparticles that by oxidative dissolution generated silver ions. The silver ions were detected directly in the wet paper matrix by using a silver ion selective electrode. The analytical performance of potentiometric dot‐blot assay matched that of reflectance‐based assays, which suggests that potentiometric detection might represent a viable alternative to the conventionally used optical detection.
A novel open‐tubular capillary electrochromatography with magnetic nanoparticle coating as stationary phase
Authors: Zhu Yaxian , Zhou Chaoran , Qin Sasa , Ren Zhiyu , Zhang Lingyi , Fu Honggang , Zhang Weibing
Published: December 2011

A novel open‐tubular capillary electrochromatography (OT‐CEC) with modified core/shell magnetic nanoparticles coating as stationary phase was introduced using external magnetic force to fix magnetic nanoparticles. The magnetic nanoparticles coating inside the capillary columns could be easily regenerated by removing and re‐applying the external magnetic field. Magnetic field intensity, concentration and flow rate of nanoparticles suspension were investigated to achieve simple and stable preparation. Mixture of five organic acids was used as the marker sample to evaluate the OT‐CEC system, and the relative column efficiency of anthranilic acid reaches 220 000 plates/m. The excellent within‐column and between‐column repeatability has been testified with the RSDs of retention time of less than 1.51 and 5.29%, respectively. The aqueous extract of rhizoma gastrodiae was analyzed by the OT‐CEC system, and 23 peaks were eluted in 30 min. Compared with conventional open‐tubular capillary column, this new system shows faster separation speed and higher column efficiency from the larger surface area of nanoparticles. It has great potential in the method development for the analysis of complex samples, since magnetic coating can effectively prolong the column life by expediently replacing stationary phase to eliminate the pollution or irreversible adsorption.
Predicting physical equations of soil detachment by simulated concentrated flow in Ultisols (subtropical China)
Authors: Wang Jun‐guang , Li Zhao‐xia , Cai Chong‐fa , Yang Wei , Ma Ren‐ming , Zhang Guo‐biao
Published: December 2011

Soil detachment in concentrated flow is due to the dislodging of soil particles from the soil matrix by surface runoff. Both aggregate stability and shear strength of the topsoil reflect the erosion resistance of soil to concentrated runoff, and are important input parameters in predicting soil detachment models. This study was conducted to develop a formula to predict soil detachment rate in concentrated flow by using the aggregate stability index (As), root density (Rd) and saturated soil strength (σs) in the subtropical Ultisols region of China. The detachment rates of undisturbed topsoil samples collected from eight cultivated soil plots were measured in a 3.8 m long, 0.2 m wide hydraulic flume under five different flow shear stresses (τ = 4.54, 9.38, 15.01, 17.49 and 22.54 Pa). The results indicated that the stability index (As) was well related with soil detachment rate, particularly for results obtained with high flow shear stress (22.54 Pa), and the stability index (As) has a good linear relationship with concentrated flow erodibility factors (Kc). There was a positive linear relationship between saturated soil strength (σs) and critical flow shear stress (τc) for different soils. A significant negative exponential relationship between erodibility factors (Kc) and root density (Rd) was detected. This study yielded two prediction equations that allowed comparison of their efficiency in assessing soil detachment rate in concentrated flow. The equation including the root density (Rd) may have a better correlation coefficient (R2 = 0.95). It was concluded that the formula based on the stability index (As), saturated soil strength (σs) and root density (Rd) has the potential to improve methodology for assessing soil detachment rate in concentrated flow for the subtropical Chinese Ultisols. Copyright © 2012 John Wiley & Sons, Ltd.
Heun und Hamel – Repräsentanten der Mechanik um 1900
Authors: Bremer Hartmut
Published: December 2011

Zu Beginn des zwanzigsten Jahrhunderts, zu einer Zeit, in der die klassische Mechanik längst als abgeschlossen propagiert wurde, treten Karl Heun und Georg Hamel auf den Plan. Ihnen ist wesentlich der weitere Ausbau der analytischen Mechanik mit zu verdanken, insbesondere im Neuland der nichtholonomen Systeme (Hamelsche Gleichungen, heute meist Hamel‐Boltzmann‐Gleichungen genannt). Es wird gezeigt, welche Auswirkungen ihre Forschertätigkeit auf das zwanzigste Jahrhundert, ja, bis heute hat (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Chemical and isotopic methods for management of artificial recharge in Mazraha Station (Damascus Basin, Syria)
Authors: Zakhem Boulos Abou , Hafez Rania
Published: December 2011

Artificially enhancing recharge rate into groundwater aquifer at specially designed facilities is an attractive option for increasing the storage capacity of potable water in arid and semi‐arid region such as Damascus basin (Syria). Two dug wells (I and II) for water injection and 24 wells for water extraction are available in Mazraha station for artificial recharge experiment. Chemical and stable isotopes (δ2H and δ18O) were used to evaluate artificial recharge efficiency. 400 to 500*103 m3 of spring water were injected annually into the ambient shallow groundwater in Mazraha station, which is used later for drinking purpose. Ambient groundwater and injected spring water are calcium bicarbonate type with EC about 880 ± 60 μS/cm and 300 ± 50 μS/cm, respectively. The injected water is under saturated versus calcite and the ambient groundwater is over saturated, while the recovered water is near equilibrium. It was observed that the injection process formed a chemical dilution plume that improves the groundwater quality. Results demonstrate that the hydraulic conductivity of the aquifer is estimated around 6.8*10−4 m/s. The effective diameter of artificial recharge is limited to about 250 m from the injection wells. Mixing rate of 30% is required in order to reduce nitrate concentration below 50 mg/l which is considered the maximum concentration limit for potable water. Deuterium and oxygen‐18 relationship demonstrates that mixing line between injected water and ambient groundwater has a slope of 6.1. Oxygen‐18 and Cl− plot indicates that groundwater salinity origin is from mixing process, and no dissolution and evaporation were observed. These results demonstrate the efficiency of the artificial recharge experiments to restore groundwater storage capacity and to improve the water quality. Copyright © 2011 John Wiley & Sons, Ltd.
Glycated hemoglobin and cancer incidence and mortality in the Atherosclerosis in Communities (ARIC) Study, 1990–2006
Authors: Joshu Corinne E. , Prizment Anna E. , Dluzniewski Paul J. , Menke Andy , Folsom Aaron R. , Coresh Josef , Yeh Hsin C. , Brancati Frederick L. , Platz Elizabeth A. , Selvin Elizabeth
Published: December 2011

Diabetes is a risk factor for many cancers; chronic hyperglycemia is hypothesized to be, in part, explanatory. We evaluated the association between glycated hemoglobin, a time‐integrated glycemia measure, and cancer incidence and mortality in nondiabetic and diabetic men and women. We conducted a prospective study of 12,792 cancer‐free participants attending the second visit (1990–1992) of the Atherosclerosis Risk in Communities (ARIC) Study. We measured glycated hemoglobin in whole‐blood samples using HPLC. Incident cancers were ascertained from registries and hospital records through 2006. We estimated multivariable‐adjusted hazard ratios (HR) of cancer incidence and mortality for nondiabetic participants with values ≥5.7% (elevated), nondiabetic participants with <5.0% (low) and diabetic participants all compared with nondiabetic participants with 5.0–5.6% (normal). We ascertained 2,349 incident cancer cases and 887 cancer deaths. Compared with nondiabetic women with normal glycated hemoglobin, nondiabetic women with elevated values had an increased risk of cancer incidence (HR:1.24; 95% CI:1.07,1.44) and mortality (HR:1.58; 95% CI:1.23,2.05) as did diabetic women (incidence, HR:1.30; 95% CI:1.06,1.60, mortality, HR:1.96; 95% CI:1.40,2.76). Nondiabetic women with low values also had increased risk. Diabetic women with good glycemic control (<7.0%) had a lower cancer risk than those with higher values. Glycated hemoglobin in nondiabetic and diabetic men, and diabetes were not statistically significantly associated with total cancer risk. Our findings support the hypothesis that chronic hyperglycemia, even in the nondiabetic range, increases cancer risk in women. Maintaining normal glycated hemoglobin overall, and good glycemic control among diabetic adults, may reduce the burden of cancer, especially in women.
Quantifying Photoinitiation Efficiencies in a Multiphotoinitiated Free‐Radical Polymerization
Authors: Voll Dominik , Hufendiek Andrea , Junkers Tanja , Barner‐Kowollik Christopher
Published: December 2011

Online size exclusion chromatography–electrospray ionization–mass spectrometry (SEC/ESI–MS) is employed for quantifying the overall initiation efficiencies of photolytically generated radical fragments. In a unique experiment, we present the first quantitative and systematic study of methyl‐substituted acetophenone‐type photoinitiators being employed in a single cocktail to initiate the free‐radical polymerization of methyl methacrylate (MMA) in bulk. The photoinitiators are constituted of a set of two known and four new molecules, which represent an increasing number of methyl substituents on their benzoyl fragment, that is, benzoin, 4‐methylbenzoin, 2,4‐dimethylbenzoin, 2,4,6‐trimethylbenzoin, 2,3,5,6‐tetramethylbenzoin, and 2,3,4,5,6‐pentamethylbenzoin. The absolute quantitative evaluation of the mass spectra shows a clear difference in the initiation ability of the differently substituted benzoyl‐type radical fragments: Increasing the number of methyl substituents leads to a decrease in incorporation of the radical fragments.
On the stability of 2D state‐space models
Authors: Bouagada Djillali , Dooren Paul Van
Published: December 2011

In this paper, we consider the problem of stability of two‐dimensional linear systems. New sufficient conditions for the asymptotic stability are derived in terms of linear matrix inequalities. Copyright © 2011 John Wiley & Sons, Ltd.
A note on stable perturbations of Moore–Penrose inverses
Authors: Li Zhao , Xu Qingxiang , Wei Yimin
Published: December 2011

Perturbation bounds for Moore–Penrose inverses of rectangular matrices play a significant role in the perturbation analysis for linear least squares problems. In this note, we derive a sharp upper bound for Moore–Penrose inverses, which is better than a well known existing one. Copyright © 2011 John Wiley & Sons, Ltd.
Early impact of smoking on lung function, health, and well‐being in adolescents
Authors: Rosewich Martin , Schulze Johannes , Eickmeier Olaf , Adler Susanne , Rose Markus A. , Schubert Ralf , Zielen Stefan
Published: December 2011

Background

Smoking is the single most important risk factor for the development of chronic obstructive pulmonary disease, and more than 80% of adult smokers started smoking before the age of 20. The aim of our study was to evaluate the early impact of smoking on lung function, health, and well‐being in adolescents.

Methods

Twenty‐four non‐smokers (10 male, 14 female, mean age 17.6 years) and 24 smokers (mean of 3.5 pack‐years; 15 male, 9 female, mean age 17.8 years) were compared in terms of lung function, bronchial hyperreactivity (BHR), levels of exhaled carbon monoxide (eCO), exhaled nitric oxide (eNO), and blood counts. A questionnaire containing items from the ISAAC study was used to detect differences in health and well‐being.

Results

There were no significant differences in lung function values between non‐smokers and smokers (VC 95% vs. 103%, FEV1 106% vs. 116%, FEV1%/VC MAX 94.6% vs. 95.2%), whereas BHR significantly differed (P < 0.05). Furthermore, significant differences were found for eCO, eNO, Hb, leukocytes, and neutrophils. Health and well‐being in terms of sleep and physical activity were significantly worse in smokers.

Conclusion

Our results suggest an early impact of smoking on health after as few as 3.5 pack‐years. Early signs of smoking are an increase in BHR, changes in blood count and a decrease of eNO even before changes in lung function become apparent. Pediatr Pulmonol. 2012; 47:692–699. © 2011 Wiley Periodicals, Inc.
Relationship of adherence determinants and parental spirituality in Cystic Fibrosis
Authors: Grossoehme Daniel H. , Opipari‐Arrigan Lisa , VanDyke Rhonda , Thurmond Sophia , Seid Michael
Published: December 2011

The course of cystic fibrosis (CF) progression in children is affected by parent adherence to treatment plans. The Theory of Reasoned Action (TRA) posits that intentions are the best behavioral predictors and that intentions reasonably follow from beliefs (“determinants”). Determinants are affected by multiple “background factors,” including spirituality. This study's purpose was to understand whether two parental adherence determinants (attitude towards treatment and self‐efficacy) were associated with spirituality (religious coping and sanctification of the body). We hypothesized that parents' attitudes toward treatment adherence are associated with these spiritual constructs. A convenience sample of parents of children with CF aged 3–12 years (n = 28) participated by completing surveys of adherence and spirituality during a regular outpatient clinic visit. Type and degree of religious coping was examined using principal component analysis. Adherence measures were compared based on religious coping styles and sanctification of the body using unpaired t‐tests. Collaborative religious coping was associated with higher self‐efficacy for completing airway clearance (M = 1070.8; SD = 35.8; P = 0.012), for completing aerosolized medication administration (M = 1077.1; SD = 37.4; P = 0.018), and for attitude towards treatment utility (M = 38.8; SD = 2.36; P = 0.038). Parents who attributed sacred qualities to their child's body (e.g., “blessed” or “miraculous”) had higher mean scores for self‐efficacy (airway clearance, M = 1058.6; SD = 37.7; P = 0.023; aerosols M = 1070.8; SD = 41.6; P = 0.020). Parents for whom God was manifested in their child's body (e.g., “My child's body is created in God's image”) had higher mean scores for self‐efficacy for airway clearance (M = 1056.4; SD = 59.0; P = 0.039), aerosolized medications (M = 1068.8; SD = 42.6; P = 0.033) and treatment utility (M = 38.8; SD = 2.4; P = 0.025). Spiritual constructs show promising significance and are currently undervalued in chronic disease management. Pediatr Pulmonol. 2012; 47:558–566. © 2011 Wiley Periodicals, Inc.