bluuebunny/crossref_metadata_2025 huggingface dataset:
Is the degree of clonality of forest herbs dependent on gap age? Using fingerprinting approaches to assess optimum successional stages for montane forest herbs
Authors: Patsias Kathrin , Bruelheide Helge
Published: October 2011

Using molecular fingerprinting (amplified fragment length polymorphism [AFLP] method), we explored the potential of small‐scale population analysis for understanding colonization patterns of herb layer species in forests after canopy disturbance. We investigated three common forest understorey species with different life forms (Trientalis europaea, Calamagrostis villosa, and Vaccinium myrtillus) in the Harz Mountains in Germany in three different gap age classes and undisturbed forest. For two of them (T. europaea and C. villosa), we analyzed clone sizes and clonal structure. We hypothesized that clone sizes depend on age since gap formation and are affected by light availability. Mean patch sizes of V. myrtillus, T. europaea, and C. villosa formed were 3.7 m2, 27.9 m2, and 40.6 m2, respectively. Trientalis europaea and C. villosa patches consisted mostly of more than one genet. Largest clone sizes of T. europaea were encountered in gaps of intermediate successional age (15–60 years, averaged minimum estimation of clone sizes: 6.56 m2) whereas clone size of C. villosa was found to be independent from gap age and had a mean minimum clone size of 0.49 m2. In both species, clone size was positively related to light availability. Additionally, there was a positive relationship between clone size and ramet density for T. europaea and C. villosa. Genetic variation was higher within populations of T. europaea and C. villosa than among populations. Trientalis europaea was the only species with a clear genetic isolation by distance, pointing at an equilibrium between gene flow and genetic drift. In conclusion, we showed that forest canopy gap dynamics clearly affect the small‐scale structure of populations of understorey plants. Species with high lateral growth rates, such as T. europaea offer the possibility to serve as “ecological clock” for dating ecological processes.
Genetic and phenotypic differentiation between invasive and native Rhododendron (Ericaceae) taxa and the role of hybridization
Authors: Erfmeier Alexandra , Tsaliki Marina , Roß Christel A. , Bruelheide Helge
Published: October 2011

Hybridization has been repeatedly put forward to explain the invasiveness of Rhododendron ponticum L. in the British Isles. The present study investigates the pattern of ecotypic differentiation and hybridization among native North American R. catawbiense and R. maximum, native R. ponticum from Georgia and Spain, and invasive R. ponticum from Ireland and aims to assess the contribution of hybridization for Rhododendron invasion in the British Isles. Six populations per taxon were analyzed with AFLP markers for genetic dissimilarity, subjected to germination and growth experiments, and tested for frost hardiness. We assessed variation in morphological and ecological characteristics to identify traits displaying evidence of hybridization, thus, promoting invasiveness. Molecular marker analyses revealed a clear distinction between North American R. catawbiense and R. maximum on the one hand, and all R. ponticum populations on the other hand, displaying a complete intermixture of native Spanish and invasive Irish populations. Multivariate analyses of traits revealed leaf length–width ratio, relative growth rates (RGRs) in leaf length, root biomass, and shoot–root ratio to significantly discriminate between the different taxa and unequivocally assigned invasive Irish R. ponticum to the Spanish phenotypes. While the Irish R. ponticum had similar growth traits as conspecific native R. ponticum provenances, germination and biomass allocation were more similar to North American R. catawbiense and R. maximum. Hybridization did not contribute to explaining invasiveness of R. ponticum in Ireland. The similarity in germination and biomass allocation of invasive Irish R. ponticum and North American species has evolved independently and can more probably be attributed to an independent shift within the Ponticum cluster in Ireland.
Sustainable Building in Japan – Observations on a Market Transformation Policy
Authors: Sunikka‐Blank Minna , Iwafune Yumiko
Published: October 2011

Despite the lack of mandatory thermal requirements in the housing sector, an average Japanese household consumes around one‐third of the energy for heating and cooling compared with a UK or German household. Based on a policy analysis and interviews, this paper identifies the concept and policies for sustainable building in Japan considering the characteristics of the building stock and household energy use behaviour. Energy and housing policies are described in terms of regulations, fiscal instruments and labels, and visualized in the context of a market transformation. The research shows that the Japanese policy has a clear preference for market‐based instruments. Thermal regulations are limited to large developments only (over 300 m2) and exclude most of the residential sector. The market transformation is likely to work with appliances, and the Top Runner programme has proved to be an effective policy in making a current market leader a future standard, but the ‘scrap and build’ housing policy leaves little incentive for energy investments in the building sector; in 24 years the resale value of a Japanese home declines to almost zero and the payback time of most environmental measures exceeds the life‐cycle of a building. As the implementation of environmental policies is voluntary, and the insulation levels low, the low heating demand per household seem to be due to different behavioural culture. The research concludes the necessity of introducing mandatory thermal regulations in housing in addition to market based instruments in order to gain further savings in the housing sector. Copyright © 2011 John Wiley & Sons, Ltd and ERP Environment.
Tectonic framework of southern Bastar Craton, Central India: a study based on different spatial information data sets
Authors: Yellappa T. , Chetty T. R. K. , Santosh M.
Published: October 2011

We present here a regional tectonic fabric analysis of the southern margin of the Bastar Craton, Central India, obtained from different spatial data sets that include Shuttle Radar Topographic Mission (SRTM), Landsat ETM+ (Enhanced Thematic Mapper) and IRS (Indian Remote sensing Satellite) P6‐LISS3, integrated with available geological information, as well as field and microscopic observations. The southern margin of the Bastar Craton exhibits large‐scale structures, such as regional‐scale folds, major shear zones and associated tectonic fabric affected by strong brittle–ductile deformation. The deformational features are related to large‐scale thrusting, regional compression, and episodic igneous activity during the Precambrian, and display a major tectonic control on magmatism and the evolution of a shear zone system. The NW–SE to E–W and NE–SW trending brittle to ductile shear zones traversing the craton display both dextral as well as sinistral displacements. Well‐developed kinematic indicators include, sheared quartz veins, tension gashes, rotated porphyroblasts, S–C fabrics, pinch‐and‐swell structures, sigmoidal foliations and riedel fractures that are well preserved in the basement Sukma–Bengpal supracrustals, as well as in the younger granitoids of the Dongargarh Supergroup. Large‐scale well‐developed NW–SE trending isoclinal folding in the basement gneisses and major folding in mafic intrusions in the south‐western margin and tight, upright doubly‐plunging large‐scale folds in the eastern margins of the craton represent two major tectonic events. These events can be correlated to large‐scale thrusts and suggest an initial N–S compression of the craton followed by E–W thrusting at different intervals during the tectonic evolution of the craton. The occurrence of several NW–SE trending mafic dykes parallel to the shear zones indicate that regional‐scale tensile stresses were operating during the Proterozoic, associated with a possible continental rift environment in the centre of the craton. The structural pattern obtained, together with the structures mapped with the coherence of remote sensing images, give significant information and an opportunity to reconstruct the timing, style of deformation and its kinematics in the southern part of the Bastar Craton and provide important constraints on the kinematics of the shear zone system and evolution of the craton. Copyright © 2011 John Wiley & Sons, Ltd.
Potential role of nonstatin cholesterol lowering agents
Authors: Trapani Laura , Segatto Marco , Ascenzi Paolo , Pallottini Valentina
Published: October 2011

Although statins, 3β‐hydroxy‐3β‐methylglutaryl coenzyme A reductase (HMGR) inhibitors, have revolutionized the management of cardiovascular diseases by lowering serum low density lipoproteins, many patients suffer from their side effects. Whether the statin side effects are related to their intrinsic toxicity or to the decrease of HMGR main isoprenoid end products, which are essential compounds for cell viability, is still debated. In addition to HMGR, the key and rate limiting step of cholesterol synthesis, many enzymes are involved in this multi‐step pathway whose inhibition could be taken into account for a “nonstatin approach” in the management of hypercholesterolemia. In particular, due to their unique position downstream from HMGR, the inhibition of squalene synthase, farnesyl diphosphate farnesyltransferase (FDFT1), squalene epoxidase (SQLE), and oxidosqualene cyclase:lanosterol synthase (OSC) should decrease plasma levels of cholesterol without affecting ubiquinone, dolichol, and isoprenoid metabolism. Thus, although FDFT1, SQLE and OSC are little studied, they should be considered as perspective targets for the development of novel drugs against hypercholesterolemia. Here, structure–function relationships of FDFT1, SQLE, and OSC are reviewed highlighting the advantages that the downstream inhibition of HMGR could provide when compared to the statin‐based therapy. © 2011 IUBMB IUBMB Life, 63(11): 964–971, 2011
Genetic basis of antibiotic resistance in pathogenic Acinetobacter species
Authors: Poirel Laurent , Bonnin Rémy A. , Nordmann Patrice
Published: October 2011

Antibiotic resistance in Acinetobacter spp., particularly Acinetobacter baumannii, is increasing rapidly. A. baumannii possesses two intrinsic β‐lactamase genes, in addition to weak permeability and efflux systems, that together confer a natural reduced susceptibility to antibiotics. In addition, numerous acquired mechanisms of resistance have been identified in A. baumannii. The very high genetic plasticity of A. baumannii allows an accumulation of resistance determinants that give rise to multidrug resistance at an alarming rate. The role of novel genetic elements, such as resistance islands, in concentrating antibiotic resistance genes in A. baumannii requires detailed investigation in the near future. © 2011 IUBMB IUBMB Life, 63(12): 1061–1067, 2011
Peroxisome degradation in mammals
Authors: Ezaki Junji , Kominami Eiki , Ueno Takashi
Published: October 2011

This review summarizes the historical aspects of the study of peroxisome degradation in mammalian cells. Peroxisomes have diverse metabolic roles in response to environmental changes and are degraded in a preferential manner, by comparison with cytosolic proteins. This review introduces three hypotheses on the degradation mechanisms: (a) the action of the peroxisome‐specific Lon protease; (b) the membrane disruption effect of 15‐lipoxygenase; and (c) autophagy that sequesters and degrades the organelles by lysosomal enzymes. Among these hypotheses, autophagy is now recognized as the most important mechanism for excess peroxisome degradation. One of the most striking characteristics of peroxisomes is that they are markedly proliferated in the liver by the administration of hypolipidemic drugs and industrial plasticizers. The effects of these substances were fully reversed after withdrawal of the substances, and most of the excess peroxisomes were selectively degraded and recovered to a normal number and size. Autophagic degradation of peroxisomes has been examined using this characteristic phenomenon. Excessive peroxisome degradation that occurs after cessation of hypolipidemic drugs has been extensively investigated biochemically and morphologically. The evidence shows that the degradation of excess peroxisomes and peroxisomal enzymes is inhibited by 3‐methyladenine (3‐MA), a specific inhibitor of autophagy. Furthermore, in liver‐specific autophagy‐deficient mice, rapid removal of peroxisomes was exclusively impaired, and degradation of peroxisomal enzymes was not detected. Thus, the significant contribution of autophagic machinery to peroxisomal degradation in mammals was confirmed. However, the important question of the mechanism for the selective recognition of peroxisomes by autophagosomes remains to be fully elucidated. © 2011 IUBMB IUBMB Life, 63(11): 1001–1008, 2011
Spectrophotometric Determination of U(VI) with Rifampicin in Soil Samples
Authors: Lutfullah  , Sharma Saurabh , Rahmana Nafisur , Hejaz Azmi Syed Najmul
Published: October 2011

A validated spectrophotometric method has been developed for the determination of uranyl ion in soil samples. The method is based on the complexation reaction between uranyl ion and rifampicin in methanol‐water medium at room temperature. The method is followed spectrophotometrically by measuring the absorbance at 375 nm. Under the optimized experimental conditions, Beer's law is obeyed in the concentration range of 1.35–20.25 μg mL‐1 with apparent molar absorptivity and Sandell's sensitivity of 8.0 × 103 L mol‐1cm‐1 and 0.042 μg/cm2/0.001 absorbance unit, respectively. The interference of a large number of anions and cations has been investigated and the optimized conditions developed have been utilized for the determination of uranium(VI) in soil samples. The three sigma detection limit (n = 9) for uranyl ion was found to be 0.20 μg mL‐1. The proposed method was successfully applied to the determination of uranyl ion in soil samples.
Simultaneous Determination of 1,4‐Benzodiazepines and Tricyclic Antidepressants in Saliva after Sequential SPE Elution by the Same HPLC Conditions
Authors: Uddin Mohammad Nasir , Samanidou Victoria F. , Papadoyannis Ioannis N.
Published: October 2011

A new method has been described to determine both benzodiazepines (six) and tricyclic antidepressants (four) simultaneously in saliva by HPLC with a UV detector set at 240 nm using cholchicine as the internal standard. A careful specific sequential solid‐phase elution was optimized and performed to elute benzodiazepines using a mixture of methanol‐acetonitrile (1:1 v/v) followed by the elution of tricyclic antidepressants with methanol. Separation of the compounds was performed on a Kromasil column (250 × 4 mm, 5 μm) by a gradient eluents consisting of 0.05 M CH3COONH4‐acetonitrile‐methanol (55:15:30 v/v/v). The results were linear for both benzodiazepines and tricyclic antidepressants up to 20 ng μL‐1 with the correlation coefficients greater than 0.998. The sensitivity limits, LOD and LOQ were 0.08‐0.34 ng μL‐1 and 0.28‐1.13 ng μL‐1, respectively. The method is simple, fast and reliable with good specificity and sensitivity, will be suitable for use in a clinical setting, where there is a concomitant use of 1,4‐benzodiazepines and tricyclic antidepressants.
Synthesis and Biological Evaluation of New Fused Isoxazolo[4,5‐d] Pyridazine Derivatives
Authors: Faidallah Hassan M. , Khan Khalid A. , Makki Mohammed S. I.
Published: October 2011

Three new heterocyclic ring systems, isoxazolo[4,5‐d]‐1,2,4‐triazolopyridazines 12‐15, tetrazolo‐[4,3‐b]pyridazine 18 and isoxazolo[4,5‐d]pyridazino[2,3‐c]2H‐triazines 16,17 along with isoxazolo[4,5‐d]pyridazines 2, 5‐10 have been synthesized. Preliminary screening of these tricyclic heterocycles revealed that some of them possess significant antibacterial and antifungal activity.
Determination of Imidacloprid in Tomato Grown in Greenhouse Based on Copper(II) Phthalocyanine Modified Carbon Ceramic Electrode by Differential Pulse Voltammetry
Authors: Majidi Mir Reza , Asadpour‐Zeynali Karim , Bamorowat Mehdi , Nazarpur Mohammad
Published: October 2011

A new sol‐gel derived electrocatalytic carbon ceramic electrode was prepared by incorporating copper(II) phthalocyanine (CuPc) in a carbon ceramic network. This electrode was used as a sensitive electrochemical sensor for determination of the insecticide Imidacloprid (1‐(6‐chloro‐3‐pyridylmethyl)‐N‐nitro‐imidazolidin‐2‐ylideneamine) by differential pulse voltammetry (DPV). The resulting modified electrode exhibits a cathodic peak potential shifted positively and an increasing in cathodic peak current in comparison with unmodified electrode. The redox properties of this modified electrode at various pH values and CuPc percentage were investigated. The catalytic current obtained from differential pulse voltammetry is linearly dependent on Imidacloprid concentration over the two linear ranges of 0.67‐17 μM and 17‐93 μM with correlation coefficient of R2 = 0.9999 and R2 = 0.990, respectively. The detection limit for Imidacloprid was found to be 0.28 μM according to lower linear range. Possible interferences from several common pesticides were also evaluated. The inherent stability, high sensitivity, low detection limit and low cost for each preparation are advantages of this sensor. Determination of Imidacloprid in commercial formulation and residual Imidacloprid in tomato grown in greenhouse (protected cultivation) was also conducted. The results obtained from commercial formulation were completely consistent with those obtained through the standard high‐performance liquid chromatography (HPLC) method.
Immobilized Fullerene C60‐Enzyme‐Based Electrochemical Glucose Sensor
Authors: Lin Li‐Hsin , Shih Jeng‐Shong
Published: October 2011

A mixed‐valence cluster of cobalt(II) hexacyanoferrate and fullerene C60‐enzyme‐based electrochemical glucose sensor was developed. A water insoluble fullerene C60‐glucose oxidase (C60‐GOD) was prepared and applied as an immobilized enzyme on a glassy carbon electrode with cobalt(II) hexacyanoferrate for analysis of glucose. The glucose in 0.1 M KCl/phosphate buffer solution at pH = 6 was measured with an applied electrode potential at 0.0 mV (vs Ag/AgCl reference electrode). The C60‐GOD‐based electrochemical glucose sensor exhibited efficient electro‐catalytic activity toward the liberated hydrogen peroxide and allowed cathodic detection of glucose. The C60‐GOD electrochemical glucose sensor also showed quite good selectivity to glucose with no interference from easily oxidizable biospecies, e.g. uric acid, ascorbic acid, cysteine, tyrosine, acetaminophen and galactose. The current of H2O2 reduced by cobalt(II) hexacyanoferrate was found to be proportional to the concentration of glucose in aqueous solutions. The immobilized C60‐GOD enzyme‐based glucose sensor exhibited a good linear response up to 8 mM glucose with a sensitivity of 5.60 × 102 nA/mM and a quite short response time of 5 sec. The C60‐GOD‐based glucose sensor also showed a good sensitivity with a detection limit of 1.6 × 10‐6 M and a high reproducibility with a relative standard deviation (RSD) of 4.26%. Effects of pH and temperature on the responses of the immobilized C60‐GOD/cobalt(II) hexacyanoferrate‐based electrochemical glucose sensor were also studied and discussed.
Isocratic Separation of Dansylated Biogenic Amines on a C8‐Bonded Silica Column under the LC Elution of Methanol‐Based Mobile Phase
Authors: Yeh Jian‐De , Chen Shushi
Published: October 2011

Under the elution of methanol‐based mobile phase, the isocratic resolution of 12 biogenic amines, including 1 aromatic, 2 heterocyclic and 9 aliphatic amines, as the dansylated derivatives has been accomplished in less than 25 minutes on a 15 cm C8‐bonded column. The resolution can not be reproduced on other examined alkyl‐bonded phases (e.g., C4 and C18) under the same chromatographic conditions, or in the reversed‐phase mode. The retention, mainly as a result of hydrophobic interaction between analyte and stationary phase, can be adjusted by varying the percentage of methanol in the mobile phase. Also, incorporating acetic acid as additive to the mobile phase to protonate the analyte and silanol groups that are little shielding on the surface of silica gel reduces the dipole‐dipole interaction, and thus the retention scale, which in turn deteriorates the resolution. Furthermore, the elution reversal is plausible for some of analytes as a greater percent of acetic acid is used in the elution. Values of correlation coefficients (R2) range between 0.9995 and 0.9996, indicating good linearity.
Synthesis and Crystal Structures of the Molybdenum(II) Complexes with the N,N‐dimethylthiocarbamoyl Containing Ligand: Crystal Structures of [Mo(CO)2(η2‐S2COEt)(η2‐SCNMe2)(PPh3)] and [Mo(CO)2(η2‐S2CNC4H8)(η2‐SCNMe2)(PPh3)]
Authors: Yih Kuang‐Hway , Wang Hsiao‐Fen , Lee Gene‐Hsiang , Huang Shou‐Ling
Published: October 2011

The reaction of the thiocarbamoyl‐molybdenum complex [Mo(CO)2(η2‐SCNMe2)(PPh3)2Cl] 1, with EtOCS2K and C4H8NCS2NH4 in dichloromethane at room temperature yielded the seven coordinated ethyldithiocarbonate thiocarbamoyl‐molybdenum complex [Mo(CO)2(η2‐S2COEt)(η2‐SCNMe2)(PPh3)] 2, and the dithiocarbamate thiocarbamoyl‐molybdenum complex [Mo(CO)2(η2‐S2CNC4H8)(η2‐SCNMe2)(PPh3)] 3. The geometry around the metal atom of compounds 2 and 3 are capped octahedrons as revealed by X‐ray diffraction analyses. The thiocarbamoyl and ethyldithiocarbonate or pyrrolidinyldithiocarbamate ligands coordinate to the molybdenum metal center through the carbon and sulfur and two sulfur atoms, respectively. Structure parameters, NMR, IR and Mass spectra are in agreement with the crystal chemistry of the two compounds.
Convertible Fluorous Sulfonate Linker for the Synthesis of Diverse Library Scaffolds
Authors: Kadam Asha , Ding Shan , Piqani Bruno , Zhang Wei
Published: October 2011

Aryl perfluorooctanesulfonates (fluorous sulfonate) have been developed as triflates and nonaflates alternatives for Pd‐catalyzed coupling reactions to form C‐C, C‐N, C‐S, C‐H, and C‐CN bonds. They also serve as phase‐tags for fluorous solid‐phase extraction (F‐SPE) to facilitate product purifications. Other synthetic techniques such as microwave reactions and multicomponent reactions are combined with the fluorous linker strategy to further increase synthetic efficiency. The utility of fluorous sulfonate linkers in the synthesis of biologically interested library scaffolds is summarized in this short review article.
Synthesis of Au/Al2O3 Nanocatalyst and its Application in the Reduction of p‐Nitrophenol
Authors: Yazid Hanani , Adnan Rohana , Farrukh Muhammad Akhyar , Hamid Shafida Abdul
Published: October 2011

Gold (Au) nanoparticles supported on alumina (Al2O3) were prepared at several pH levels via the deposition‐precipitation (DP) method. The effects of pH at below and above the isoelectric point (IEP) of Al2O3 as well as the pH adjustment before and after the addition of the support into the gold chloride solution were investigated. The results revealed the formation of cationic, clusters and metallic Au on alumina. The catalytic activity of these species was tested in the reduction of p‐nitrophenol (p‐NP) using hydrazine as a reductant. The catalytic reaction was monitored spectrophotometerically and the highest rate constant (k‐) achieved based on pseudo first order kinetic model was 12.7 × 10‐3 s‐1. Structural and elemental characterizations of the supported gold nanoparticles were carried out using X‐ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy‐dispersive X‐rays (EDX), atomic absorption spectrometry (AAS), and ultraviolet‐visible spectroscopy (UV‐Vis).
Studies of Interaction between Ergosta‐4,6,8(14),22‐tetraen‐3‐one (Ergone) and Human Serum Albumin by Molecular Spectroscopy and Modeling
Authors: Sun Yang , Zhao Yingyong , Li Guobo , Yang Shengyong , Hu Xiaoyun , Fan Jun
Published: October 2011

Our previous experimental results have shown that ergosta‐4,6,8(14),22‐tetraen‐3‐one (ergone) is one of the main bioactive components of Polyporus umbellatus. The efficacy of ergone binding to human serum albumin (HSA) is critical for pharmacokinetic behavior of ergone. The interactions between ergone and HSA under simulative physiological conditions were investigated by the methods of fluorescence spectroscopy, absorption and circular dichroism spectroscopy. Fluorescence data revealed that the fluorescence quenching of HSA by ergone was the result of the formation of the ergone‐HSA complex. According to the modified Stern‐Volmer equation, the binding constants (Ka) between ergone and HSA were determined. The thermodynamic parameters, enthalpy change (ΔH) and entropy change (ΔS) for the reaction were calculated to be 0.989 kJ mol‐1 and 11.214 J mol‐1 K‐1, indicating that the hydrogen bonds and hydrophobic interactions played a dominant role in the binding of ergone to HSA. The conformational investigation showed that the presence of ergone decreased the α‐helical content of HSA and induced the slight unfolding of the polypeptides of protein. Furthermore, displacement experiments using warfarin and ibuprofen indicated that ergone could bind to site I of HSA, which was also in agreement with the results of the molecular modeling.
Synthesis, Characterization and Photophysical Properties of Iridium(III) Bis‐cyclometallated Complexes Containing 1,1‐Dithiolates
Authors: Sie Wu‐Sian , Jian Jing‐Yu , Shiu Kom‐Bei
Published: October 2011

A series of neutral Ir(III)‐based heteroleptic complexes with a formula of [Ir(η2‐(C∧N))2(η2‐(S∧S))] ((C∧N)‐ = ppy‐, (S∧S)‐ = Et2NCS2‐ (2a), MeOCS2‐ (2b), EtOCS2‐ (2c), iPrOCS2‐ (2d); (C∧N)‐ = tpy‐, (S∧S) = Et2NCS2‐ (3a), MeOCS2‐ (3b), EtOCS2‐ (3c), iPrOCS2‐ (3d); (C∧N)‐ = epb‐ , (S∧S)‐ = Et2NCS2‐ (4a), MeOCS2‐ (4a), EtOCS2‐ (4a); ppyH = 2‐phenylpyridine; tpyH = 2‐(4′‐tolyl)pyridine; epbH = ethyl 4‐(2′‐pyridyl)benzate) was synthesized and characterized. The crystal structure of complex 2d was also determined. The electron‐releasing substituents on (C∧N)‐ or (S∧S)‐ blueshift λmax values.
Preparation and Electrochemical Behaviour of Silver Pentacyanonitrosylferrate Film Modified Glassy Carbon Electrode and Its Electrocatalytic Oxidation to L‐cysteine
Authors: Liu Suqin , Dai Gaopeng
Published: October 2011

A glassy carbon (GC) electrode modified with silver pentacyanonitrosylferrate (AgPCNF) film as a redox mediator was fabricated. Cyclic voltammetry was used to study the redox property of AgPCNF modified electrode. The modified electrode showed a well‐defined redox couple due to [AgIFeIII/II(CN)5NO]1‐/2‐system. The effects of scan rates, supporting electrolytes and solution pHs were studied on the electrochemical behavior of the modified electrode. The feasibility of using the AgPCNF modified electrode to measure L‐cysteine was investigated. It showed an excellent electrocatalytic activity towards the oxidation of L‐cysteine and the anodic currents were proportional to the L‐cysteine concentration in the range of 0.1 μM to 20 μM, the linear regression equation is Ipa(μA) = ‐68.58 ‐ 5.78CL‐cysteine (μM), with a correlation coefficient 0.998 for N = 23. The detection limit was down to 3.5 × 10‐8 M (three times the ratio of signal to noise).
Speciation and Determination of Trace Amount of Inorganic Arsenic in Water, Environmental and Biological Samples
Authors: Shirkhanloo Hamid , Mousavi Hassan Zavvar , Rouhollahi Ahmad
Published: October 2011

A new speciation and preconcentration method based on dispersive liquid‐liquid microextraction has been developed for trace amounts of As(III) and As(V) in urine and water samples. At pH 4, As(III) is complexed with ammoniumpyrrolidine dithiocarbamate and extracted into 1‐Hexyl‐3‐methylimidazolium hexafluorophosphate, as an ionic liquid (IL) and As(III) is determined by electrothermal atomic absorption spectrometery (ETAAS). Arsenic(V) in the mixing solution containing As(III) and As(V) was reduced by using KI and ascorbic acid in HCl solution and then the procedure was applied to determination of total arsenic. Arsenic(V) was calculated as the difference between the total arsenic content and As(III) content. The effect of various parameters on the recovery of the arsenic ions has been studied. Under the optimum conditions, the enrichment factor 135 was obtained. The proposed method was successfully applied to the determination of trace amounts of As(III) and As(V) in water and biological samples.
Computational Study of the Substitution Effect on the Mechanism for the Aza‐ and Arsa‐Wittig Reactions
Authors: Liao Hsin‐Yi
Published: October 2011

The aza‐ and arsa‐Wittig reactions HM=PH3 + O=CHX → HM=CHX + O=PH3 (M = N, As; X = H, F, Cl, Me, OMe, NMe2, CMe3) were examined using the density functional theory calculations. All of the structures were completely optimized at the B3LYP/6‐311++G** level of theory. The main finding of this work is that the difference between singlet‐triplet splitting of O=CHX and HM=PH3 play an important role in determining the kinetic and thermodynamic stability of the aza‐ and arsa‐Wittig reactions. When HM=PH3 with more ylidic character is utilized, the reaction has a smaller activation energy and a larger exothermicity.
Physical‐chemical Test Platform for Room Temperature, Far‐infrared Ray Emitting Ceramic Materials (cFIR)
Authors: Leung Ting‐Kai , Huang Pai‐Jung , Chen Yi‐Chien , Lee Chi‐Ming
Published: October 2011

Ceramic far‐infrared (cFIR) emitting materials are sources of room temperature FIR radiation that allow non‐thermal irradiation of biological tissue. In this study, we explored some interesting physical and chemical effects that have not been reported. We investigated the effects of cFIR irradiation of sorghum wine using gas chromatography with solid‐phase micro‐extraction (GC‐SPME) to demonstrate enhancement on volatility; monitored pH changes resulting from irradiation on acetic acid; and used UV spectroscopy to identify and quantify chemical changes. On the basis of the results, we deduced that cFIR possesses the ability of weakening hydrogen bond and exhibits chemical reduction change. The methods above provide a relatively convenient and cost‐effective test platform to demonstrate the application of cFIR as an effective alternative to biological assay.
Crown Ethers Bearing 18C6 Unit; Sensory Molecules for Fabricating PVC Membrane Lead Ion‐selective Electrodes
Authors: Zamani A. A. , Khorsihdi N. , Mofidi Z. , Yaftian M. R.
Published: October 2011

Crown ethers bearing 18C6 unit 18‐crown‐6 (18C6), dicyclohexyl18‐crown‐6 (DC18C6) and dibenzo18‐crown‐6 (DB18C6) have been examined as ion sensing materials for fabricating lead ion‐selective potentiometric sensors. Best performance of the electrode based upon 18C6 ionophore was achieved by using a membrane including 9% ionophore, 30% polyvinyl chloride (PVC), 2% oleic acid and 59% dibutylphthalate (DBP). The optimum composition for the sensors based on DC18C6 and DB18C6 was provided by the compositions: 9% DC18C6, 30% PVC, 1.5% sodium tetraphenyl borate (NaTBP), 59.5% DBP; and 5.9% DB18C6, 29.7% PVC, 2.5% NaTBP and 61.9% DBP, respectively. The linear response range of the electrode based on 18C6 (1 × 10‐6‐1 × 10‐3 M) differs from that presented by the DC18C6‐ and DB18C6‐based electrodes (1 × 10‐5‐1 × 10‐2 M). All the sensors were shown rapid response time (<12 s). The detection limit of the electrodes varies as 5.6 × 10‐7, 6.3 × 10‐6 and 7.1 × 10‐6 M, for 18C6‐, DC18C6‐ and DB18C6‐based electrodes, respectively. The selectivity of the electrodes towards lead ions over some mono‐, di‐ and trivalent metal ions was evaluated. The lifetime of the electrode based on DC18C6 or DB18C6 ionophores was found to be more than three months, while it was shorter for 18C6‐based electrode. The application of the electrodes in aqueous samples was assessed.
Electrochemical Deposition of Gold Nanoparticles on Pencil Graphite by Fast Scan Cyclic Voltammetry
Authors: Etesami Mohammad , Karoonian Fatemeh Salehi , Mohamed Norita
Published: October 2011

Gold nanoparticles (AuNPs) were electrodeposited on the surface of pencil graphite (PG) by fast scan cyclic voltammetry without using any additives in acidic medium. The effect of deposition time on the size of electrodeposited AuNPs was investigated in sulfuric acid as a supporting electrolyte. The deposition time was varied by varying the scan rate, number of cycles and applied potential range. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X‐ray diffraction (XRD) were used for characterization of PG and electrodeposited AuNPs. The results confirmed that nanosized gold particles (20 ± 8 nm) were deposited on the PG substrate with almost spherical geometry.
Quantitative Evaluation of Trace Elements in Sediments of the Tamsui River via Instrumental Neutron Activation Analysis
Authors: Chang Chih‐Chia , Chen Shiuan‐Chih , Tsai Chin‐Feng , Lin Jye‐Bin , Chang Yih‐Hsin , Chen Chien‐Yi , Pan Lung‐Kwang , Lin Ding‐Bang
Published: October 2011

The present study examined concentrations of trace elements in the sediments collected from 31 locations along the banks of Tamsui River by instrumental neutron activation analysis. The Tamsui River is famous for containing a unique area of naturally preserved mangrove in northern Taiwan. It is also the second longest river among the 3 major rivers in Taiwan. A total of 11 nuclides, including Mg, Al, Ti, Mn, Na, Sc, As, Br, La, Fe and Cs, were identified. The categories and measurements of nuclides detected were interpreted according to the sampling locations or chemical attributes characteristics. A dimensionless index (CI) was introduced to explore the quantitative correlation among the detected nuclides. A smaller CI corresponded to a stronger correlation between a pair of nuclides, such that the correlation between the nuclides can be interpreted through a series of quantified indices. The minimum detectable concentration (MDC) for As‐76 was fluctuated around 0.67 ± 0.09 μg/g due to the variations of background counts in various gamma spectra.
Synthesis and X‐ray characterization of 2,5,6‐trisubstituted imidazo[2,1‐b][1,3,4]thiadiazole derivatives
Authors: Da Yu‐Xia , Zhu Ji‐Hua , Zhang Zhang , Jia Xiao‐Dong , Yang Cai‐Xia , Quan Zheng‐Jun
Published: October 2011

A series of 2,5,6‐trisubstituted imidazo[2,1‐b][1,3,4]thiadiazoles via Mannich reaction of imidazo[2,1‐b][1,3,4]thiadiazoles with morpholine and formaldehyde were synthesized. Structures of all the newly synthesized compounds are well supported by spectral data such as IR, NMR, Mass, and Elemental analysis. Compound 3a has been confirmed by X‐ray diffraction studies. J. Heterocyclic Chem., (2012).
Pediatric hospital medicine: A strategic planning roundtable to chart the future
Authors: Rauch Daniel A. , Lye Patricia S. , Carlson Douglas , Daru Jennifer A. , Narang Steve , Srivastava Rajendu , Melzer Sanford , Conway Patrick H.
Published: October 2011

Given the growing field of Pediatric Hospital Medicine (PHM) and the need to define strategic direction, the Society of Hospital Medicine, the American Academy of Pediatrics, and the Academic Pediatric Association sponsored a roundtable to discuss the future of the field. Twenty‐one leaders were invited plus a facilitator utilizing established health care strategic planning methods. A “vision statement” was developed. Specific initiatives in 4 domains (clinical practice, quality of care, research, and workforce) were identified that would advance PHM with a plan to complete each initiative. Review of the current issues demonstrated gaps between the current state of affairs and the full vision of the potential impact of PHM. Clinical initiatives were to develop an educational plan supporting the PHM Core Competencies and a clinical practice monitoring dashboard template. Quality initiatives included an environmental assessment of PHM participation on key committees, societies, and agencies to ensure appropriate PHM representation. Three QI collaboratives are underway. A Research Leadership Task Force was created and the Pediatric Research in Inpatient Settings (PRIS) network was refocused, defining a strategic framework for PRIS, and developing a funding strategy. Workforce initiatives were to develop a descriptive statement that can be used by any PHM physician, a communications tool describing “value added” of PHM; and a tool to assess career satisfaction among PHM physicians. We believe the Roundtable was successful in describing the current state of PHM and laying a course for the near future. Journal of Hospital Medicine 2012. © 2011 Society of Hospital Medicine
UV–VIS detection of amino acids in liquid chromatography: Online post‐column solid‐state derivatization with Cu(II) ions
Authors: Kubíc̆ková Anna , Kubíc̆ek Vojtĕch , Coufal Pavel
Published: October 2011

In this work, we describe the introduction of a post‐column solid‐state reactor in the HPLC system used for the analyses of amino acids. The reactor used was filled with copper(II) oxide. Passage of the analytes through the reactor leads to the formation of Cu(II) complexes. Unlike free amino acids, the Cu‐complexes show significant absorbance in the UV region and accordingly sensitivity of UV–VIS detection is increased by two to three orders of magnitude. As a result of this improvement in sensitivity, we have obtained LOD values in micromolar range and good linearity over the studied concentration range (5.0×10−5 to 2.0×10−3 mol/L). The method exhibits advantages typical of solid‐state reactors, such as negligible loss of efficiency due to the derivatization, simplicity of realization and a long‐term durability. The presented system brings an easy and versatile solution for UV–VIS detection of coordinating compounds, which do not normally absorb well in the UV–VIS region.
Overcoming nasal discomfort—A novel method for office‐based laser surgery
Authors: Verma Sunil P. , Dailey Seth H.
Published: October 2011

Objectives:

The passage of a flexible channeled laryngoscope for office‐based laser laryngeal surgery can be limited by narrow nasal passages, nasal discomfort, or both. We describe a novel method for delivering the laser fiber transorally with simultaneous laryngeal visualization to avoid these limitations. This technique can be employed with instruments available in most otolaryngologists' offices.

Methods:

A retrospective chart review was performed and procedural details were recorded.

Results:

Technical description: A laser fiber was threaded through the shaft of an Abraham cannula. A patient was seated in an otolaryngology examination chair and instructed to hold and stabilize his own tongue. Using his nondominant hand, the surgeon placed a rigid angled telescope into the patient's oral cavity for laryngeal visualization. Using his dominant hand, the surgeon simultaneously introduced the laser fiber threaded through the Abraham cannula into the patients oral cavity and guided it towards the patients larynx. Energy from the PDL, KTP, or CO2 flexible laser fibers was then delivered for management of glottic papillomatosis and leukoplakia. Treatment of glottic lesions was achieved successfully in all cases with titration endpoints identical to the transnasal approach.

Conclusions:

For patients who cannot tolerate transnasal passage of a flexible channeled laryngoscope during office‐based laser laryngeal surgery, an attractive alternative to surgery under general anesthesia is the transoral technique. This approach does not rely on distal chip endoscopes and can be performed with existing equipment in an office setting.
Pullulan Hydrogels Improve Mesenchymal Stem Cell Delivery into High‐Oxidative‐Stress Wounds
Authors: Wong Victor W. , Rustad Kristine C. , Glotzbach Jason P. , Sorkin Michael , Inayathullah Mohammed , Major Melanie R. , Longaker Michael T. , Rajadas Jayakumar , Gurtner Geoffrey C.
Published: October 2011

Cell‐based therapies for wound repair are limited by inefficient delivery systems that fail to protect cells from the acute inflammatory environment. Here, a biomimetic hydrogel system is described that is based on the polymer pullulan, a carbohydrate glucan known to exhibit potent antioxidant capabilities. It is shown that pullulan hydrogels are an effective cell delivery system and improve mesenchymal stem cell survival and engraftment in high‐oxidative‐stress environments. The results suggest that glucan hydrogel systems may prove beneficial for progenitor‐cell‐based approaches to skin regeneration.

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Tissue‐Specific Stem Cell Differentiation in an in vitro Airway Model
Authors: Prytherch Zoë , Job Claire , Marshall Hilary , Oreffo Victor , Foster Martyn , BéruBé Kelly
Published: October 2011

The respiratory tract is the primary site of exposure to airborne compounds, with the bronchial epithelium providing one of the first lines of defence. A growing need exists for an accurate in vitro model of the bronchial epithelium. Here, normal human bronchial epithelial (NHBE) cells cultured at an air/liquid interface create a fully differentiated, in‐vivo‐like model of the human bronchial epithelium. Developmental characterisation includes (i) trans‐epithelial electrical resistance, (ii) morphology and (iii) bronchial cell specific stains/markers. It is concluded that the basal/progenitor cells create a pseudo‐stratified, mucociliary NHBE model containing basal, serous, Clara, goblet and ciliated cells, reflective of the normal human bronchial epithelium (days 24–33 ALI culture).

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π‐Conjugated Polymers Consisting of 9,10‐Dihydrophenanthrene Units
Authors: Yamamoto Takakazu , Tokimitsu Ryouichi , Asao Takahiro , Iijima Takayuki , Fukumoto Hiroki , Koizumi Take‐aki , Fukuda Takashi , Ushijima Hirobumi
Published: October 2011

π‐Conjugated polymers consisting of 9,10‐disubstituted 9,10‐dihydrophenenthrene, with the substituents octyl, 2‐ethylhexyl, ‐OSiBu3, etc., units are prepared by organometallic polycondensation. Homopolymers (PH2Ph(9,10‐R)) have a π‐conjugation system similar to that of polymers of 9,9‐dialkylfluorene and show UV‐Vis peaks at ≈380 nm. In addition to the peak at ≈380 nm, some homopolymers give rise to a peak at a longer wavelength, suggesting molecular assembly of the polymers. X‐ray diffraction data support the molecular assembly. The homopolymers show photoluminescence (PL) with PL peaks at ≈430 nm, and PL spectrum of the polymer film is essentially unchanged after heating the polymer film at 150 °C in air. The homopolymers undergo electrochemical p‐doping at about 1.5 V versus Ag+/Ag.
Reversibly Switchable pH‐ and Thermoresponsive Core–Shell Nanogels Based on Poly(NiPAAm)‐graft‐poly(2‐carboxyethyl‐2‐oxazoline)s
Authors: Zschoche Stefan , Rueda Juan Carlos , Binner Marcus , Komber Hartmut , Janke Andreas , Arndt Karl‐Friedrich , Lehmann Stefan , Voit Brigitte
Published: October 2011

Amphiphilic graft copolymers with a thermosensitive PNiPAAm backbone and pH‐sensitive hydrophilic poly(2‐carboxyethyl‐2‐oxazoline) graft chains are synthesized. In aqueous solution, stable micelle‐like aggregates are formed by increasing the temperature in the pH range 4.5–5.5. The micelles are crosslinked by electron‐beam irradiation, yielding stable core–shell nanogels of about 100 nm diameter with reversible thermo‐ and pH‐dependent swelling behavior. The temperature sensitivity is provided by a conformational change in the PNiPAAm core, whereas the thickness of the poly(2‐carboxyethyl‐2‐ oxazoline) corona depends on pH. The reversible bisensitivity of core‐crosslinked nanogels is verified by DLS, while AFM measurements demonstrate the predicted core–shell structures of the aggregates.
Quasi‐Solid‐State Dye‐Sensitized Solar Cells Using Nanocomposite Gel Polymer Electrolytes Based on Poly(propylene carbonate)
Authors: Choi Yeon Jeong , Han Yonggyu , Ok Myoung‐Ahn , Kim Dong‐Won
Published: October 2011

Poly(propylene carbonate) (PPC) is synthesized from the copolymerization of CO2 and propylene oxide. Novel nanocomposite gel polymer electrolytes (GPEs) are prepared by utilizing PPC, organic solvents containing a redox couple, and aluminum oxide nanoparticles for application in dye‐sensitized solar cells (DSSCs). The quasi‐solid‐state DSSC assembled with optimized nanocomposite GPEs exhibits a relatively high conversion efficiency of 6.16% at 100 mW cm−2 and better stability than DSSC with liquid electrolyte.
Formation of Highly Aligned, Single‐Layered, Hollow Fibrous Assemblies and the Fabrication of Large Pieces of PLLA Membranes
Authors: Yang Jen‐Chang , Lee Sheng‐Yang , Tseng Wen‐Chin , Shu Yao‐Chi , Lu Jen‐Chieh , Shie Han‐Shian , Chen Chien‐Chung
Published: October 2011

Large pieces of paper‐thin PLLA membranes are prepared and characterized as single‐layered hollow fibrous assemblies with an extremely high degree of fiber alignment. The diameter of the electrospun hollow fibers is in the range of some tens of micrometers with a wall thickness of a few micrometers. They are best described as 2D arrays of highly aligned microtubes. The mechanical properties of the membranes are studied. A processing map is constructed using the applied electric field strength and the concentration (viscosity) of the electrospinning dope. The influence of factors such as the field strength and weight and viscosity of the jetted solutions is discussed. The results will help in the future fabrication of highly anisotropic scaffolds for tissue engineering applications.

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Classification of New Melt‐Processable PTFE: Comparison of Emulsion‐ and Suspension‐Polymerized Materials
Authors: Frick Achim , Sich Dorota , Heinrich Gert , Stern Claudia , Schlipf Michael
Published: October 2011

A new melt‐processable PTFE material is presented and characterized that provides new and economical solutions in polymer technology while bridging the gap between perfluorinated PTFE and fluorothermoplastic materials such as perfluoroalkoxy resins. Thermal transitions, MW and MWD, and microstructures of the melt‐processable PTFE materials are investigated and compared to standard PTFE, modified PTFE, and PFA materials. The influence of the polymerization type used for the preparation of the melt‐processable PTFE (emulsion and suspension polymerization) on the MWD and the comonomer distribution are discussed.

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Handedness correlates with the dominant Parkinson side: A systematic review and meta‐analysis
Authors: van der Hoorn Anouk , Burger Huibert , Leenders Klaus L. , de Jong Bauke M.
Published: October 2011

Parkinson's disease (PD) characteristically presents with asymmetrical symptoms, contralateral to the side of the most extensive cerebral affection. This intriguing asymmetry, even included in the definition for diagnosing PD, however, is still part of a mystery. The relation with handedness as a common indicator of cerebral asymmetry might provide a clue in the search for causal factors of asymmetrical symptom onset in PD. This possible relationship, however, is still under debate. The objective of this study was to establish whether a relation between handedness and dominant PD side exists. We searched for cross‐sectional or cohort studies that registered handedness and onset side in PD patients in PubMed, EMBASE, and Web of Science from their first record until 14 February 2011. Data about handedness and dominant PD side was extracted. Authors who registered both but not described their relation were contacted for further information. Odds ratios (ORs) were analyzed with a fixed effect Mantel‐Haenszel model. Heterogeneity and indications of publication bias were limited. Our electronic search identified 10 studies involving 4405 asymmetric PD patients. Of the right‐handed patients, 2413 (59.5%) had right‐dominant and 1644 (40.5%) had left‐dominant PD symptoms. For the left‐handed patients this relation was reversed, with 142 (40.8%) right‐dominant and 206 (59.2%) left‐dominant PD symptoms. Overall OR was 2.13 (95% confidence interval [CI], 1.71–2.66). Handedness and symptom dominance in PD are firmly related with each other in such a way that the PD symptoms emerge more often on the dominant hand‐side. Possible causal factors are discussed. © 2011 Movement Disorder Society