bluuebunny/crossref_metadata_2025 huggingface dataset:
Patterns of shrub diversity and tree regeneration across topographic and stand-structural gradients in a Mediterranean forest
Authors: Tíscar Oliver Pedro
Published: April 2015

Aim of study: This study aimed to determine the influence of topography and stand-structure on the characteristics of shrub communities and tree regeneration in a Mediterranean forest.Area of study: The Navahondona forest in Cazorla mountain range (SE Spain).Material and Methods: Data from 298 inventory plots were analysed by means of Generalized Linear Models (GLM) to test the effects of aspect, altitude and stand basal area on shrub cover and diversity. Likewise, the effects of these three factors plus shrub cover on the recruitment of Spanish black pine (Pinus nigra spp. salzmannii) and two oak species (Quercus ilex and Q. faginea) were analysed by GLMs. Additionally, the influence of topography and forest structure on the specific distribution of shrub species was analysed with multivariate methods.Main results: Shrub cover and diversity were generally low and did not change across the topographic gradient. Tree density was the only study variable affecting (negatively) shrub cover. However, shrub composition changed with aspect and altitude. Both pine and oak regeneration benefited from partial tree cover at intermediate values of stand density, but only oak regeneration was facilitated by shrubs.Research highlights: Altitude, aspect and stand basal area influence the characteristics of shrub communities and tree regeneration. Proactive management of dense pinewoods might be needed to increase shrub and tree diversity.Key words Pinus nigra; Quercus sp.; altitude; aspect; facilitation; Shannon diversity index.
Effects of fine root length density and root biomass on soil preferential flow in forest ecosystems
Authors: Zhang Yinghu , Niu Jianzhi , Yu Xinxiao , Zhu Weili , Du Xiaoqing
Published: April 2015

Aim of study: The study was conducted to characterize the impacts of plant roots systems (e.g., root length density and root biomass) on soil preferential flow in forest ecosystems.Area of study: The study was carried out in Jiufeng National Forest Park, Beijing, China.Material and methods: The flow patterns were measured by field dye tracing experiments. Different species (Sophora japonica Linn, Platycladus orientalis Franco, Quercus dentata Thunb) were quantified in two replicates, and 12 soil depth were applied. Plant roots were sampled in the sieving methods. Root length density and root biomass were measured by WinRHIZO. Dye coverage was implied in the image analysis, and maximum depth of dye infiltration by direct measurement.Main results: Root length density and root biomass decreased with the increasing distance from soil surface, and root length density was 81.6% higher in preferential pathways than in soil matrix, and 66.7% for root biomass with respect to all experimental plots. Plant roots were densely distributed in the upper soil layers. Dye coverage was almost 100% in the upper 5-10 cm, but then decreased rapidly with soil depth. Root length density and root biomass were different from species: Platycladus orientalis Franco > Quercus dentata Thunb > Sophora japonica Linn.Research highlights: The results indicated that fine roots systems had strong effects on soil preferential flow, particularly root channels enhancing nutrition transport across soil profiles in forest dynamics.Key words: soil preferential flow; preferential pathways; soil matrix; root length density; root biomass.
Germination ecology of the endemic Iberian daffodil Narcissus radinganorum (Amaryllidaceae). Dormancy induction by cold stratification or desiccation in late stages of embryo growth
Authors: Herranz Sanz José Mª , Copete Carreño Elena , Copete Carreño Miguel Ángel , Ferrandis Gotor Pablo
Published: April 2015

Aim of study: We studied the germination ecology of a threatened daffodil in order to develop a protocol to produce plants ex-situ from seeds, a key tool for population reinforcement.Area of study: Experiments were carried out both outdoors and in the laboratory in Albacete (Spain).Material and methods: Embryo length, radicle and shoot emergence were analyzed to determine the level of morphophysiological dormancy (MPD). Effects on germination of cold stratification or desiccation in late stages of embryo growth were also studied.Main results: Mean embryo length in fresh seeds was 1.36 mm, needing to grow up to 2.20 mm to be able to germinate. In the laboratory, embryo growth occurred during warm stratification (28/14, 25/10ºC), and then radicle emerged when temperatures went down (15/4ºC in darkness). Phenology study in outdoors conditions revealed that embryo grew during summer-early autumn, short time after seed dispersal in nature (i.e., May); radicle emerged in autumn. The shoot however did not emerge until late winter-early spring, because it was physiologically dormant and required a cold (5ºC) period of 30 days to break dormancy. Early cold temperatures interrupted the embryo growth and induced dormancy in seeds whose embryo had grown 30% with respect to the initial length. Desiccation in seeds whose embryo had grown 30% did not induce dormancy, but did it when the embryo growth reached 70%.Research highlights: Seeds of Narcissus radinganorum have deep simple epicotyl MPD.Key words: dormancy break; radicle emergence; shoot emergence; epicotyl MPD; phenology; secondary dormancy.
High seed dispersal ability of Pinus canariensis in stands of contrasting density inferred from genotypic data
Authors: López de Heredia Unai , Nanos Nikos , García-del-Rey Eduardo , Guzmán Paula , López Rosana , Venturas Martin , Gil-Muñoz Pascual , Gil Luis
Published: April 2015

Aim of the study: Models that combine parentage analysis from molecular data with spatial information of seeds and seedlings provide a framework to describe and identify the factors involved in seed dispersal and recruitment of forest species. In the present study we used a spatially explicit method (the gene shadow model) in order to assess primary and effective dispersal in Pinus canariensis.Area of study: Pinus canariensis is endemic to the Canary Islands (Spain). Sampling sites were a high density forest in southern slopes of Tenerife and a low density stand in South Gran Canaria. Materials and methods: We fitted models based on parentage analysis from seeds and seedlings collected in two sites with contrasting stand density, and then compared the resulting dispersal distributions.Main results: The results showed that: 1) P. canariensis has a remarkable dispersal ability compared to other pine species; 2) there is no discordance between primary and effective dispersals, suggesting limited secondary dispersal by animals and lack of Janzen-Connell effect; and 3) low stand densities enhance the extent of  seed dispersal, which was higher in the low density stand.Research highlights: The efficient dispersal mechanism of P. canariensis by wind inferred by the gene shadow model is congruent with indirect measures of gene flow, and has utility in reconstructing past demographic events and in predicting future distribution ranges for the species.Keywords: Bayesian inference; Canary Islands; gene shadow model; microsatellites; parentage analysis.
Seed production and recruitment in primary and harvested Nothofagus pumilio forests: Influence of regional climate and years after cuttings
Authors: Torres Ana D. , Cellini Juan M. , Lencinas María V. , Barrera Marcelo D. , Soler Rosina , Diaz-Delgado Ricardo , Martínez Pastur Guillermo J.
Published: April 2015

Aim of study: Harvesting proposals (e.g. variable retention) for Nothofagus pumilio forests are based on canopy opening, to increase recruitment and enhance seedling growth, by modifying light and soil moisture. Seed production and seedling recruitment will define the success of harvesting, where remnant forest structure are the main influence factors, as well as biotic and abiotic factors. The objective was to analyse seed production, seedling recruitment and recruitment efficiency in primary and harvested forests through variable retention along the first 10 years after harvesting, as well as the influence of regional climate.Area of study: The study were conducted in a pure Nothofagus pumilio forest located in centralTierra del Fuego (54º18’ S, 67º49’ W), where harvested stands with variable retention and unmanaged forests were sampled in long-term permanent plots.Material and methods: Data of forest regeneration plots were used (n=72) (2007 a 2014), and forest structure and seed production (2006 a 2013) were also measured. Regional climate was characterised for these years from satellite images (Sea Surface Temperature) and climate re-analysis models (rainfall and temperature of land surface).Main results: Harvesting modified forest structure; however, aggregated retention maintained some characteristics of the primary unmanaged forests. These changes influenced seed production and recruitment. Seed production and recruitment were related to crown cover and the amount of seed production; however, recruitment efficiency was not affected by harvesting. The studied variables significantly changed along the years after harvesting. Seed production and recruitment were also related to regional climate factors, where it was possible to explain their variations through temperature (e.g. summer temperature) and rainfall (e.g. winter rainfall) for the different retention types in harvested forests and the primary forests.Research highlights: Variable retention harvesting generated different micro-conditions that influence seed production and recruitment. These variables were related to canopy cover. However, recruitment efficiency was not affected by harvesting. Seed production and recruitment (primary forests and harvested stands) were related to regional climate factors and their variations can be explained from variables related to temperature and rainfall.Key words: regeneration; forest management; crown cover; regional climate; modelling; Tierra del Fuego.
A Spline Group – Korovkin Approximation Theorem
Authors: Al-Muhja Malik Saad
Published: April 2015

In this paper, using homogeneous groups, we prove a Korovkin type approximation theorem for a spline groupby using the notion of a generalization of positive linear operator.
VÝSLEDKY VRTNÉHO PRŮZKUMU NA LOKALITĚ HOLUBICE (SPODNOBADENSKÉ SEDIMENTY KARPATSKÉ PŘEDHLUBNĚ)
Authors: Nehyba Slavomír , Zborník Václav , Jašková Vladimíra
Published: April 2015

Early Badenian deposits of the Carpathian Foredeep were newly studied in the sedimentary successions from drill holes Holubice 1 and Holubice 2. Facies analysis together with study of grain size, the shape and roundness of the coarsest grains, the mineral compositions of selected heavy minerals (garnet, rutile) and the gamma-ray spectra, were all used for better understanding the depositional setting and provenance. Studied sediments were deposited in coastal and shallow marine environments. Six lithofacies was recognised in the sedimentary succession in the drill holes. They have been combined into two facies associations – lower clastic one and upper carbonate one, refl ecting deposition in shallow marine settings, upward shallowing trend and reduction of siliciclastic input. The primary source of the material is located mainly in the metamorphic rocks (gneisses, amphibolites and granulites). The spectral gamma-ray logs show vertical organization, which is consistent with the facies analysis and partly also grain-size. A significant reduction of terrigenous input is connected with deposition of carbonates (sandy limestones) in the upper part of the succession.
STAV VÝZKUMU BLOKOVOBAHENNÍCH PROUDŮ NA ZÁPADNÍCH SVAZÍCH KEPRNICKÉ HORNATINY (HRUBÝ JESENÍK)
Authors: Tichavský Radek , Šilhán Karel
Published: April 2015

The debris flows are fast dangerous processes initiated also in mid-mountains of the Czech Republic, frequently damaging forest stands. An occurrence of debris flows in the Hrubý Jeseník Mts. is connected with steep slopes and high-gradient channels predisposed by landuse, morphometric, lithological and especially climatic conditions. The first stage of research was implemented in the Klepáčský brook drainage basin. In 2013, a field geomorphological mapping and sampling of disturbed trees for dendrogeomorphic research (tree ring analysis) were carried out. There are preserved several remnants of former debris flows. The oldest accumulations in a form of terraces above the channel bottom, younger but stable and overgrown lateral levees and recent fresh frontal lobes directly in the channel were distinguished. At least 9 debris flow events in the last 60 years were dated in the Klepáčský brook from the tree ring analysis; the year 2010 was the last known and the most represented period in the tree ring series. Spatial dimensions, magnitudes of debris flows and places of their origin has been changed during the last decades so we could analyze their different behaviour patterns (e. g. 1991, 1997 and 2010), recorded in disturbed trees along the brook. The research will be extended to other basins in the Keprnická hornatina Mts., focusing on factors of debris flow predisposition and chronology with an application of dendrogeomorphic methods being actually the most accurate approach for dating of events in far-flung tree-covered basins.
VNITŘNÍ ZONÁLNOST TĚLES HORNIN TĚŠÍNITOVÉ ASOCIACE VE SLEZSKÉ JEDNOTCE: KORELACE PETROGRAFICKÝCH A PETROFYZIKÁLNÍCH PARAMETRŮ
Authors: Schuchová Kristýna , Dolníček Zdeněk
Published: April 2015

This article is focused on petrography of igneous rocks of the teschenite association and its correlation with selected petrophysical parameters. These igneous rocks were studied at three localities in the Silesian unit (Outer Western Carpathians) – Hodslavice, Žilina near Nový Jičín and Tichá. We conducted petrographic study (including modal composition based on planimetry) and then we compared results with previously published data on magnetic susceptibility and density of the same rock samples. The primary magmatic phases (clinopyroxenes, amphibole, biotite, opaque phases, feldspars and analcime) show in all cases less or more signs of post-magmatic alteration, giving rise mainly to secondary chlorite, carbonate and “limonite”. The amount of chlorite ranges from 21 to 23, 3 to 9, and 16 to 35 mod. % and those of carbonate vary from 5 to 15, 3 to 4, and 16 to 24 mod. % in Hodslavice, Žilina near Nový Jičín, and Tichá, respectively. The values of magnetic susceptibility range from 5.56 × 10-8 to 7.66 × 10-5, 5.07 × 10-7 to 1.61 × 10-5, and 2.46 × 10-7 to 2.93 × 10-5 SI and those of density are between 2.50 and 2.77, 2.66 to 3.88, and 2.65 to 2.86 g/cm3 in Hodslavice, Žilina near Nový Jičín, and Tichá, respectively. Correlation of petrographic and petrophysical parameters suggests that various postmagmatic alterations (including chloritization, carbonatization and weathering associated with formation of limonite) can influence the values of magnetic susceptibility and density. The intensity of these alterations varies significantly among samples and sites.
GEOMECHANICKÉ VLASTNOSTI NEOGENNÍCH JÍLŮ NA ÚZEMÍ MĚSTA BRNA
Authors: Fürychová Petra , Melichar Rostislav , Poul Ivan
Published: April 2015

Neogene clays in Brno area are formations belonging to the Carpathian Foredeep Basin. They form common foundation soil in this strongly urbanized area. Due to their specific mechanical characteristics and a large spreaded area in Brno a detailed study of the geomechanical properties of Neogene clays has practical importance for engineering geology and geotechnics. There are compared analyzed data of physical and mechanical properties from 81 engineering-geological reports at the Brno agglomeration (452 samples of Neogene clays from 180 bores). There are presented the anomalous, distant values, arithmetic average and mode of the Neogene clays. On the basis of assumed data from various geological-engineering reports are defined typical characteristics of these soils. Neogene clays are fine-grained cohesive soils. In terms of ČSN EN ISO 14688-1, 14688-2 and UCSC classification these are classified mainly as clay or silt with high, very high or extremely high plasticity. It is usually with high plasticity index, stiff and very stiff consistence and with medium and high undrained shear strength. Low values of cohesion could be related to soil damaged by landslide movements. Due to its unfavourable properties, Neogene clays refer to partly suitable environment for shallow strip-foundations mainly due to the possibilities of volume changes in the subground. For all projection of foundations, there should be paid special attention to good engineering-geological investigation at real site.
SULFIDICKÉ FÁZE VE STŘEDOVĚKÝCH STRUSKÁCH PO TAVBĚ Ag RUD V JIHLAVSKÉM A HAVLÍČKOBRODSKÉM RUDNÍM REVÍRU
Authors: Kapusta Jaroslav , Janíčková Kateřina , Dolníček Zdeněk , Malý Karel
Published: April 2015

Sulphide phases were studied in glassy and crystalline slags after smelting of polymetallic ores from the Jihlava and the Havlíčkův Brod Ore Districts. Sulphides usually form droplets from μm to mm in diameter. They exhibit complex composition with prevalence of pyrrhotite and sphalerite. Rudashevskyite (Fe,Zn)S occurs as a result of isomorphic substitution of Fe by Zn. Cu was rarely identified as native metal but usually it represents an admixture in a Cu-Fe-S phase with stoichiometry close to bornite. Pb is mainly present as galena or lead monoxide. Native silver as well as Ba-analogon of apatite were also identifi ed. For evaluation of potential release of heavy metals due to the preferential dissolution of sulphides and metallic phases, leaching tests in aqueous solution of sodium acetate were carried out. Data from leaching tests were compared with limit values defined by USEPA (1994) for solid wastes. The limit values were not exceeded only in case of Cd and As. The limit for Pb was exceeded in all cases except for one sample. For assessing of Zn and Cu limits for acute toxicity defi ned for aquatic habitats (USEPA 2006) were used; the obtained concentrations in leachates were several orders of magnitude higher.
Fatigue, Sleep Quality, and Disability in Relation to Quality of Life in Multiple Sclerosis
Authors: Tabrizi Fatemeh Moghaddam , Radfar Moloud
Published: April 2015

Background: Quality of life (QOL) is impaired in multiple sclerosis (MS) in part due to physical disability. MS-associated fatigue and poor sleep are common and treatable features of MS that affect QOL. We assessed the association between fatigue, sleep quality, and QOL in people with MS.

Methods: Cross-sectional data were collected from 217 patients with MS. Health-related QOL (MS Quality of Life-54), fatigue (Fatigue Severity Scale [FSS]), and sleep quality (Pittsburgh Sleep Quality Inventory [PSQI]) were assessed. Expanded Disability Status Scale scores were also provided by a qualified neurologist.

Results: The mean ± SD age of the 217 patients was 32.6 ± 8.6 years, and 79% were female. One hundred fifty-two patients (70.0%) were classified as poor sleepers based on PSQI scores; 122 (56.2%) had significant fatigue based on FSS results. The mean ± SE physical (PCS) and mental (MCS) health composite scores of the MSQOL-54 were 40.12 ± 1.27 and 43.81 ± 1.61, respectively. There was a strong statistically significant positive correlation between PCS scores and MCS (r = 0.58), FSS (r = 0.49), and PSQI (r = 0.52) scores. MCS scores were strongly correlated with FSS (r = 0.53) and PSQI (r = 0.35) scores. Age exhibited statistically significant negative correlations with PCS (r = −0.21) and MCS (r = −0.58) scores, and was statistically significantly correlated with FSS (r = 0.23) and PSQI (r = 0.21) scores. Expanded Disability Status Scale scores were strongly correlated with FSS scores.

Conclusions: These findings support screening of fatigue severity and sleep quality and their effects on QOL.
Cerebrovascular and blood–brain barrier impairments in Huntington's disease: Potential implications for its pathophysiology
Authors: Drouin‐Ouellet Janelle , Sawiak Stephen J. , Cisbani Giulia , Lagacé Marie , Kuan Wei‐Li , Saint‐Pierre Martine , Dury Richard J. , Alata Wael , St‐Amour Isabelle , Mason Sarah L. , Calon Frédéric , Lacroix Steve , Gowland Penny A. , Francis Susan T. , Barker Roger A. , Cicchetti Francesca
Published: April 2015

Objective

Although the underlying cause of Huntington's disease (HD) is well established, the actual pathophysiological processes involved remain to be fully elucidated. In other proteinopathies such as Alzheimer's and Parkinson's diseases, there is evidence for impairments of the cerebral vasculature as well as the blood–brain barrier (BBB), which have been suggested to contribute to their pathophysiology. We investigated whether similar changes are also present in HD.

Methods

We used 3‐ and 7‐Tesla magnetic resonance imaging as well as postmortem tissue analyses to assess blood vessel impairments in HD patients. Our findings were further investigated in the R6/2 mouse model using in situ cerebral perfusion, histological analysis, Western blotting, as well as transmission and scanning electron microscopy.

Results

We found mutant huntingtin protein (mHtt) aggregates to be present in all major components of the neurovascular unit of both R6/2 mice and HD patients. This was accompanied by an increase in blood vessel density, a reduction in blood vessel diameter, as well as BBB leakage in the striatum of R6/2 mice, which correlated with a reduced expression of tight junction‐associated proteins and increased numbers of transcytotic vesicles, which occasionally contained mHtt aggregates. We confirmed the existence of similar vascular and BBB changes in HD patients.

Interpretation

Taken together, our results provide evidence for alterations in the cerebral vasculature in HD leading to BBB leakage, both in the R6/2 mouse model and in HD patients, a phenomenon that may, in turn, have important pathophysiological implications. Ann Neurol 2015;78:160–177
Background story of the invention of efficient blue InGaN light emitting diodes (Nobel Lecture)
Authors: Nakamura Shuji
Published: April 2015

Shuji Nakamura discovered p‐type doping in Gallium Nitride (GaN) and developed blue, green, and white InGaN based light emitting diodes (LEDs) and blue laser diodes (LDs). His inventions made possible energy efficient, solid‐state lighting systems and enabled the next generation of optical storage. Together with Isamu Akasaki and Hiroshi Amano, he is one of the three recipients of the 2014 Nobel Prize in Physics. In his Nobel lecture, Shuji Nakamura gives an overview of this research and the story of his inventions***.

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Facile Hydrolysis and Alcoholysis of Palladium Acetate
Authors: Bedford Robin B. , Bowen John G. , Davidson Russell B. , Haddow Mairi F. , Seymour‐Julen Annabelle E. , Sparkes Hazel A. , Webster Ruth L.
Published: April 2015

Palladium(II) acetate is readily converted into [Pd3(μ2‐OH)(OAc)5] (1) in the presence of water in a range of organic solvents and is also slowly converted in the solid state. Complex 1 can also be formed in nominally anhydrous solvents. Similarly, the analogous alkoxide complexes [Pd3(μ2‐OR)(OAc)5] (3) are easily formed in solutions of palladium(II) acetate containing a range of alcohols. An examination of a representative Wacker‐type oxidation shows that the Pd‐OH complex 1 and a related Pd‐oxo complex 4 can be excluded as potential catalytic intermediates in the absence of exogenous water.
Structural and Biomechanical Properties of the Exchange Tissue of the Avian Lung
Authors: Maina John N.
Published: April 2015

The blood capillaries (BC) and the air capillaries (ACs) are the terminal gas exchange units of the avian lung. The minuscule structures are astonishingly strong. It is only recently that the morphologies and the biomechanical properties of the BCs and the ACs were investigated. Regarding size and shape, the BCs and the ACs differ remarkably. While they were previously claimed to be tubular (cylindrical) in shape, the ACs are rather rotund structures which interconnect across short, narrow passageways. Atypical of those in other tissues, the BCs in the exchange tissue of the avian lung comprise of distinct segments which are about as long as they are wide and which are coupled in three‐dimensions. The thin blood‐gas barrier (BGB) which separates the ACs from the BCs is peculiarly strong. The causes of the strengths of the ACs and the BCs in general and the BGB in particular are varied and controversial. Here, the recent morphological and physiological findings on the structure, biomechanical properties, and the strengths of the respiratory units of the avian lung and the BGB have been critically examined. Also, in light of the new morphological findings of the ACs and the BCs, the functional model which is currently in use to assess the gas exchange efficiency of the avian lung should be revised and the inappropriateness of the terms ‘blood capillary’ and ‘air capillary’ for the gas exchange units of the avian lung is pointed out. Anat Rec, 298:1673–1688, 2015. © 2015 Wiley Periodicals, Inc.
Late breaking trials of 2014 in coronary artery disease: Commentary covering ACC, EuroPCR, SCAI, TCT, ESC, and AHA
Authors: Tremmel Jennifer A. , Bhatt Deepak L. , Pinto Duane S. , Grines Cindy L.
Published: April 2015

With the plethora of clinical trials, it is difficult for busy interventional cardiologists to stay up to date. Therefore, the SCAI Publications Committee concisely summarizes and provides editorial commentary on the most important coronary trials from the large international meetings of 2014. The intent is to allow quick assimilation of trial results into interventional practice. © 2015 Wiley Periodicals, Inc.
“Burnt out” dilated hypertrophic cardiomyopathy causing acute LVAD thrombosis
Authors: Sivathasan Cumaraswamy , Tan Teing E. E. , Sim David , Kerk Ka Lee
Published: April 2015

Key Clinical Message

Case report illustrates obstruction encountered in a patient with end‐stage dilated hypertrophic cardiomyopathy (HCM) who underwent LVAD implantation. The morphology reversed in early postoperative period to HCM. Pump replacement required coring of the ventricular muscle. Dilated end‐stage hypertrophic cardiomyopathy can revert back to the original morphology on decompression.
Myotonic dystrophy as a cause of colonic pseudoobstruction: not just another constipated child
Authors: Glaser Andrea M. , Johnston Jennifer H. , Gleason Wallace A. , Rhoads J. Marc
Published: April 2015

Key Clinical Message

Muscular dystrophy has been traditionally associated with common gastrointestinal symptoms such as reflux, constipation, and dysphasia. In myotonic dystrophy, there are rare reports of chronic intestinal pseudoobstruction (CIPOS). We herein present a case of CIPOS requiring colectomy and with good results.
Follicular lymphoma (in situ) pattern in the bone marrow: does it indicate an early stage in disease evolution?
Authors: Alobeid Bachir , Mears John Gregory , Bhagat Govind
Published: April 2015

Key Clinical Message

Bone marrow involvement by an isolated interstitial lymphoid aggregate exhibiting the pattern and phenotype described for follicular lymphoma in situ (FLIS) has not been reported before. The detection of clinically silent FL in this case highlights the necessity of complete staging workup when such lesions are encountered in biopsies.
Function of the Support and Metal Loading on Catalytic Carbon Dioxide Reduction Using Ruthenium Nanoparticles Supported on Carbon Nanofibers
Authors: Roldán Laura , Marco Yanila , García‐Bordejé Enrique
Published: April 2015

Catalytic CO2 reduction has been performed using carbon nanofibers or nitrogen‐doped carbon nanofibers as a support for Ru nanoparticles. The catalyst that consists of 5 wt % Ru on nitrogen‐doped carbon nanofibers exhibited the highest conversion at a relatively low temperature, complete selectivity to CH4, and stable catalytic performance. The catalytic performance was substantially superior to catalysts supported on carbon nanotubes and akin to the best metal‐oxide‐supported catalyst in the literature. The characterization of the prepared catalyst by transient experiments (CO2 temperature‐programmed desorption, temperature‐programmed surface reaction, and transient response to CO2 removal) revealed that the catalyst support participates actively in the reaction. The Ru content governed the selectivity, which either favored CO formation for lower Ru contents (0.5–2 wt %) or CH4 formation for 5 wt % Ru loading. The mean Ru particle size determined by TEM was similar for each of the metal loadings. Therefore, the substantially different selectivity patterns cannot be attributed to structure sensitivity. The higher selectivity to CH4 can be explained by the enhanced supply of adsorbed hydrogen to the activated adsorbed CO intermediate, which was demonstrated to be the rate‐determining step.
Structured Ni‐CeO2‐Al2O3/Ni‐Foam Catalyst with Enhanced Heat Transfer for Substitute Natural Gas Production by Syngas Methanation
Authors: Li Yakun , Zhang Qiaofei , Chai Ruijuan , Zhao Guofeng , Liu Ye , Lu Yong
Published: April 2015

Concerns about the clean utilization of coal and the development of sustainable energy have provided a particular impetus for the exploration into the production of substitute natural gas (SNG) by syngas methanation in some parts of world. Owing to heat‐transfer limitations, current SNG technology based on a series of fixed‐bed reactors packed with oxide‐supported Ni catalysts suffers from issues such as high costs, low efficiency, and catalyst sintering. We report a monolithic Ni‐Ce‐Al2O3/Ni‐foam catalyst obtainable by modified wet‐chemical etching of Ni foam. Such a catalyst, with significantly enhanced heat transfer, is highly active, highly selective, and very stable for syngas methanation. Computational fluid dynamics calculations and experimental measurements consistently show a large reduction in the “hotspot” temperature in the Ni‐foam‐structured catalyst bed owing to high thermal conductivity. We anticipate that our approach will open a new opportunity for next‐generation SNG plant design.
Enhanced Biocatalytic Performance of Bacterial Laccase from Streptomyces sviceus: Application in the Michael Addition Sequence Towards 3‐Arylated 4‐Oxochromanes
Authors: Suljić Sanel , Mortzfeld Frederik B. , Gunne Matthias , Urlacher Vlada B. , Pietruszka Jörg
Published: April 2015

A fast and efficient laccase‐catalysed oxidation/Michael addition sequence is performed using the bacterial laccase Ssl 1 from Streptomyces sviceus under basic conditions to provide a new class of 3‐arylated 4‐oxochromanes. This approach has advantages compared to previous biocatalytic arylation protocols that use fungal laccases under slightly acidic conditions to allow a significant decrease in reaction time with improved yields and maintained regio‐ and diastereoselectivity. Furthermore, a successful diastereoselective, consecutive one‐pot approach with the use of a hydrogenation flow system combined with the laccase‐catalysed arylation was performed. Finally, the general utility of this enzyme as a superior biocatalyst for Michael additions using several nucleophiles was demonstrated. The corresponding starting material was obtained in a straightforward esterification/hydrogenation process with the latter accomplished by using the flow system.
Simple Synthesis of Conformationally Fixed Glycosamine Analogues by Beckmann Rearrangement at the Carbohydrate Ring
Authors: Umbreen Sumaira , Linker Torsten
Published: April 2015

Conformationally fixed carbohydrate analogues are promising small‐molecule inhibitors for hydrolases like O‐GlcNAcase (OGA); however, their synthesis usually requires many steps. Herein we describe cycloadditions of dichloroketene to various glycals and subsequent Beckmann rearrangements, which offer an easy and stereoselective entry to glycosamine derivatives in good yields. The reactions are applicable for hexoses, pentoses, and disaccharides, and transformations to the corresponding imidates proceed smoothly. First biological tests reveal that such imidates indeed inhibit human OGA.
Preparation and Regioselective Magnesiation or Lithiation of Bis(trimethylsilyl)methyl‐Substituted Heteroaryls for the Generation of Highly Functionalized Heterocycles
Authors: Klatt Thomas , Werner Veronika , Maximova Marina G. , Didier Dorian , Apeloig Yitzhak , Knochel Paul
Published: April 2015

A wide range of bis(trimethylsilyl)methyl (BTSM)‐ substituted heteroaryl derivatives has been prepared by using Kumada–Corriu or Negishi cross‐coupling reactions. The regioselective lithiation or magnesiation of these building blocks bearing a bulky BTSM group by using magnesium or lithium 2,2,6,6‐tetramethylpiperidide bases followed by quenching reactions with different electrophiles provides various functionalized N‐, O‐, or S‐heterocycles. Furthermore, the BTSM group can then be converted into formyl, methyl, or styryl groups to give access to a variety of highly functionalized heteroaromatics.
ChemInform Abstract: Two High‐Pressure Phases of SiS2 as Missing Links Between the Extremes of Only Edge‐Sharing and Only Corner‐Sharing Tetrahedra.
Authors: Evers Juergen , Mayer Peter , Moeckl Leonhard , Oehlinger Gilbert , Koeppe Ralf , Schnoeckel Hansgeorg
Published: April 2015

The crystal structures of two high‐pressure phases of SiS2, HP1‐SiS2 and HP2‐SiS2, obtained from the ambient‐pressure phase at 1473 K at 2.8 GPa and 3.5 GPa, resp., are determined by single crystal XRD, Raman spectroscopy, and DFT calculations.
ChemInform Abstract: Structural and Thermal Properties of Ternary Narrow‐Gap Oxide Semiconductor; Wurtzite‐Derived β‐CuGaO2.
Authors: Nagatani Hiraku , Suzuki Issei , Kita Masao , Tanaka Masahiko , Katsuya Yoshio , Sakata Osami , Miyoshi Shogo , Yamaguchi Shu , Omata Takahisa
Published: April 2015

The crystal structure of the title compound is determined by synchrotron powder XRD and discussed in comparison with other oxide semiconductors.
ChemInform Abstract: PbGa2MSe6 (M: Si, Ge): Two Exceptional Infrared Nonlinear Optical Crystals.
Authors: Luo Zhong‐Zhen , Lin Chen‐Sheng , Cui Hong‐Hua , Zhang Wei‐Long , Zhang Hao , Chen Hong , He Zhang‐Zhen , Cheng Wen‐Dan
Published: April 2015

PbGa2SiSe6 (I) and PbGa2GeSe6 (II) with mid‐IR second‐order nonlinear optical responses are prepared by solid‐state reaction of PbSe, Ga2Se3, Si (Ge), and Se in the molar ratio 1:1:1:2 (evacuated silica tube, 1023 K (1073 K for (II)), 50 h; cooling to 573 K with a rate of 3 K/h).
ChemInform Abstract: An Outstanding Second‐Harmonic Generation Material BiB2O4F: Exploiting the Electron‐Withdrawing Ability of Fluorine.
Authors: Cong Rihong , Wang Ying , Kang Lei , Zhou Zhengyang , Lin Zheshuai , Yang Tao
Published: April 2015

The non‐linear optical (NLO) material BiB2O4F is prepared by hydrothermal synthesis employing a 1:20:2 molar mixture of Bi(NO3)3, H3BO3, and NaF (autoclave, 200 °C, 3 d, ≈90% yield).
ChemInform Abstract: Soft Chemical Control of Superconductivity in Lithium Iron Selenide Hydroxides Li1‐xFex(OH)Fe1‐ySe.
Authors: Clarke Simon J.
Published: April 2015

The title compounds (x ≈ 0.2; 0.02 < y 0.15) are hydrothermally synthesized from aqueous mixtures of FeSe, LiOH, and variable amounts of Fe powder (autoclave, 200 °C, 12 d, yield given in g) and characterized by powder XRD, neutron powder diffraction, single crystal XRD, X‐ray absorption spectroscopy, muon‐spin rotation spectroscopy, and magnetic measurements.
ChemInform Abstract: An Antiferro‐to‐Ferromagnetic Transition in EuTiO3‐xHx Induced by Hydride Substitution.
Authors: Yamamoto Takafumi , Yoshii Ryuta , Bouilly Guillaume , Kobayashi Yoji , Fujita Koji , Kususe Yoshiro , Matsushita Yoshitaka , Tanaka Katsuhisa , Kageyama Hiroshi
Published: April 2015

EuTiO3‐xHx (x ≤ 0.3) is prepared by low temperature CaH2 reduction of Eu2Ti2O7 and EuTiO3 (475—650 °C, 2 d) and characterized by XRD and magnetic measurements.
ChemInform Abstract: A Sustainable Iron‐Based Sodium Ion Battery of Porous Carbon—Fe3O4/Na2FeP2 O7 with High Performance.
Authors: Ming Jun , Ming Hai , Yang Wenjing , Kwak Won‐Jin , Park Jin‐Bum , Zheng Junwei , Sun Yang‐Kook
Published: April 2015

A porous C—Fe3O4 composite anode material consisting of highly dispersed Fe3O4 nanocrystals within the porous carbon is fabricated from an EtOH solution of Pluronic F127, Fe(NO3)3, and resol‐EtOH by stirring for 1 h followed by careful drying at 100 °C and calcination under Ar (500 °C, 2 h).
ChemInform Abstract: Mesoporous Bubble‐Like Manganese Silicate as a Versatile Platform for Design and Synthesis of Nanostructured Catalysts.
Authors: Zhan Guowu , Yec Christopher C. , Zeng Hua Chun
Published: April 2015

Mesoporous bubble‐like yolk‐shell hybrids of core nanoparticles (e.g., Au, Ag, Pt, Co, Ni, Au‐Pd alloy, MoO2, Fe3O4, carbon nanotubes, and their combinations) and manganese silicate (MS) as the shell are prepared from the respective nanoparticles (NP) covered by nanosilica (precursor prepared by a modified Stoeber process through hydrolysis and condensation of TEOS) under addition of MnSO4 and Na maleate in aqueous solution (autoclave, 180 °C, 12 h).
ChemInform Abstract: Quaternary Pnictides with Complex, Noncentrosymmetric Structures. Synthesis and Structural Characterization of the New Zintl Phases Na11Ca2Al3Sb8, Na4CaGaSb3, and Na15Ca3In5Sb12.
Authors: Wang Yi , Stoyko Stanislav , Bobev Svilen
Published: April 2015

Single crystals of the new title Zintl phases are prepared by solid state reactions from mixtures of the elements in the molar ratio of Na:Ca:M:Sb = 3:3:1:4 (M: Al, Ga, In) in sealed Nb containers (1173 K, 24 h).
ChemInform Abstract: Supramolecular Recognition Influences Magnetism in [X@HVIV8VV14O54] 6‐ Self‐Assemblies with Symmetry‐Breaking Guest Anions.
Authors: Monakhov Kirill Yu. , Linnenberg Oliver , Kozlowski Piotr , van Leusen Jan , Besson Claire , Secker Tim , Ellern Arkady , Lopez Xavier , Poblet Josep M. , Koegerler Paul
Published: April 2015

Crystals of (Et4N)6 [(VO2F2)HV22O54] are prepared by mixing Et4NBF and (H4N)8 [H9V19O50]·11H2O in the molar ratio of 8.7:0.39 in aqueous solution (80 °C, 72 h, 79% yield).
ChemInform Abstract: UPTe, ThPTe and U2PTe2O: Actinide Pnictide Chalcogenides with Diphosphide Anions.
Authors: Stolze Karoline , Isaeva Anna , Schwarz Ulrich , Doert Thomas
Published: April 2015

Preparation and crystal growth of UPTe (I) is performed from a stoichiometric mixture of the elements (evacuated silica tube, 973 K, 7 d) followed by chemical transport from 1073 to 1123 K.
ChemInform Abstract: A Simple and Efficient Synthesis of Isocoumarins and Alkylidenephthalides from 3‐(1‐Hydroxycarbethoxy/alkyl)phthalides with a DEAD/PPh3/TBHP System.
Authors: Gadakh Sunita K. , Sudalai Arumugam
Published: April 2015

A facile and novel approach to the synthesis of isocoumarins and alkylidenephthalides under similar conditions is described.
ChemInform Abstract: Biotransformation of Aromatic Ketones and Ketoesters with the Non‐Conventional Yeast Pichia glucozyma.
Authors: Contente Martina Letizia , Molinari Francesco , Zambelli Paolo , De Vitis Valerio , Gandolfi Raffaella , Pinto Andrea , Romano Diego
Published: April 2015

The concurrent activity of ketoreductase and esterase of the yeast Pichia glycozyma allows the reduction of ketones and β‐ketoesters to give hydroxyesters, hydroxy acids, or lactones as products.
ChemInform Abstract: A Ball‐Milling Strategy for the Synthesis of Benzothiazole, Benzimidazole and Benzoxazole Derivatives under Solvent‐Free Conditions.
Authors: Sharma Hemant , Singh Narinder , Jang Doo Ok
Published: April 2015

The synthesis of benzothiazoles, benzimidazoles, and benzoxazoles is performed at ambient temperature under solvent‐free conditions in a ball mill in relatively short reaction times.
ChemInform Abstract: Selective Oxygenation of Alkynes: A Direct Approach to Diketones and Vinyl Acetate.
Authors: Xia Xiao‐Feng , Gu Zhen , Liu Wentao , Wang Ningning , Wang Haijun , Xia Yongmei , Gao Haiyan , Liu Xiang
Published: April 2015

Arylalkynes can be selectively converted into α‐diketones under copper catalysis, and also into vinyl acetates under metal‐free conditions, using PhI(O‐Ac)2 as oxidant.
ChemInform Abstract: BrF3—KHF2: An Air‐Stable Fluorinating Reagent.
Authors: Shishimi Toru , Hara Shoji
Published: April 2015

Air‐stable BrF3·KHF2 easily prepared from BrF3 and KHF2 is applied to desulfurizing fluorination reactions of dithioacetals, phenylthioglycosides, and trimethyl trithioorthocarboxylates.
ChemInform Abstract: Sulfur Mediated Allylic C—H Alkylation of Tri‐ and Disubstituted Olefins.
Authors: Hu Gang , Xu Jiaxi , Li Pingfan
Published: April 2015

A novel sulfur mediated allylic C—H alkylation reaction without the involvement of transition‐metal catalysts is developed.
ChemInform Abstract: Meta‐Selective Arene C—H Bond Olefination of Arylacetic Acid Using a Nitrile‐Based Directing Group.
Authors: Bera Milan , Modak Atanu , Patra Tuhin , Maji Arun , Maiti Debabrata
Published: April 2015

Phenylacetic acids (I) and (V) having a 2‐hydroxybenzonitrile substituent as directing group undergo meta‐selective olefination with acrylates and vinyl ketones.
ChemInform Abstract: Deprotection of Oximes, Imines, and Azines to the Corresponding Carbonyls Using Cu‐Nanoparticles on Cellulose Template as Green Reusable Catalyst.
Authors: Baruah Diganta , Saikia Ujwal Pratim , Pahari Pallab , Dutta Dipak Kumar , Konwar Dilip
Published: April 2015

The reactions take place under neutral conditions.
ChemInform Abstract: Catalytic Enantioselective Quick Route to Aldol‐Tethered 1,6‐ and 1,7‐Enynes from ω‐Unsaturated Aldehydes.
Authors: Garcia Jesus M. , Odriozola Jose M. , Razkin Jesus , Lapuerta Irati , Odriozola Amaiur , Urruzuno Inaki , Vera Silvia , Oiarbide Mikel , Palomo Claudio
Published: April 2015

Direct cross‐aldol reaction between ω‐unsaturated aldehydes and propargylic aldehydes is developed to yield functionalized 1,6‐ and 1,7‐enynes and the conversion of these products to bicyclic cyclopentenone derivatives by Pauson—Khand reaction is demonstrated.
ChemInform Abstract: Cinchona‐Derived Picolinamides: Effective Organocatalysts for Stereoselective Imine Hydrosilylation.
Authors: Barrulas Pedro C. , Genoni Andrea , Benaglia Maurizio , Burke Anthony J.
Published: April 2015

Several cinchona‐derived catalysts are synthesized and successful applied to the enantioselective reduction of ketomines.
ChemInform Abstract: Synthesis of Novel Carbohydrate‐Based Valine‐Derived Formamide Organocatalysts by CuAAC Click Chemistry and Their Application in Asymmetric Reduction of Imines with Trichlorosilane.
Authors: Ge Xin , Qian Chao , Chen Xinzhi
Published: April 2015

The applied catalyst can be recycled and reused at least five times.
ChemInform Abstract: Double‐Addition Reaction of Aryl Methyl Sulfones with N‐tert‐Butylsulfinyl Imines: Diastereoselective and Concise Synthesis of 2‐Sulfonylated 1,3‐Diamines.
Authors: Li Ya , Li Desheng , Zheng Tao , Li Hongsen , Ren Xinfeng
Published: April 2015

The double‐addition reaction provides bis‐addition products with excellent anti‐selectivity.
ChemInform Abstract: A Well‐Defined Monomeric Aluminum Complex as an Efficient and General Catalyst in the Meerwein—Ponndorf—Verley Reduction.
Authors: McNerney Brian , Whittlesey Bruce , Cordes David B. , Krempner Clemens
Published: April 2015

A variety of aliphatic and aromatic aldehydes and ketones are selectively reduced under mild conditions using a monomeric aluminum complex as the catalyst.
ChemInform Abstract: Pd(II)‐Catalyzed O‐Aroylation of Directing Arenes Using Terminal Aryl Alkenes and Alkynes.
Authors: Khatun Nilufa , Banerjee Arghya , Santra Sourav K. , Behera Ahalya , Patel Bhisma K.
Published: April 2015

o‐Aroylation of arenes is accomplished by an efficient Pd‐catalyzed directing group assisted reaction with terminal alkenes or alkynes.
ChemInform Abstract: Unusual Reactivity of Nitronates with an Aryl Alkyl Carbonate: Synthesis of α‐Amino Esters.
Authors: Reddy Golipalli Ramana , Mukherjee Debopreeti , Chittoory Arjun Kumar , Rajaram Sridhar
Published: April 2015

The presented method offers a safe and scalable alternative to the well‐known Strecker reaction.
ChemInform Abstract: A Palladium‐Catalyzed Carbonylative‐Deacetylative Sequence to 1,3‐Keto Amides.
Authors: Nielsen Dennis U. , Korsager Signe , Lindhardt Anders T. , Skrydstrup Troels
Published: April 2015

The reaction is accomplished by means of a two‐chambers set‐up, where in one chamber CO is stoichiometrically generated ex situ.
ChemInform Abstract: Polymer‐Anchored Ru(II) Complex as an Efficient Catalyst for the Synthesis of Primary Amides from Nitriles and of Secondary Amides from Alcohols and Amines.
Authors: Islam Sk Manirul , Ghosh Kajari , Singha Roy Anupam , Molla Rostam Ali
Published: April 2015

A novel recyclable polymer anchored Ru(II)‐complex catalyst is designed and used for the hydration of aromatic nitriles to give amides (II) in excellent yields.
ChemInform Abstract: Diastereoselective Synthesis of β‐Aminosulfones from the 1,2‐Addition to N‐(para‐methoxyphenyl) Imines.
Authors: Anderson James C. , Campbell Ian B. , Campos Sebastien , Shannon Jonathan
Published: April 2015

Sulfone substituents are found to influence the diastereoselectivity of the 1,2‐addition reaction to imines (II).
ChemInform Abstract: 1,3‐Dicyclohexylimidazol‐2‐ylidene as a Superior Ligand for the Nickel‐Catalyzed Cross‐Couplings of Aryl and Benzyl Methyl Ethers with Organoboron Reagents.
Authors: Tobisu Mamoru , Yasutome Ayaka , Kinuta Hirotaka , Nakamura Keisuke , Chatani Naoto
Published: April 2015

The developed reaction system is inapplicable to secondary benzylic ethers other than 2‐[methoxy(phenyl)methyl]naphthalene (IX).
ChemInform Abstract: Cu(OAc)2‐Catalyzed Coupling of Aromatic C—H Bonds with Arylboron Reagents.
Authors: Shang Ming , Sun Shang‐Zheng , Dai Hui‐Xiong , Yu Jin‐Quan
Published: April 2015

The arylation of various aromatic substrates proceeds selectively in the position ortho to the removable directing group.
ChemInform Abstract: Friedel—Crafts Reaction of Benzyl Fluorides: Selective Activation of C—F Bonds as Enabled by Hydrogen Bonding.
Authors: Champagne Pier Alexandre , Benhassine Yasmine , Desroches Justine , Paquin Jean‐Francois
Published: April 2015

The reaction proceeds well with benzyl fluorides only and activated arenes.
ChemInform Abstract: A Facile Access to 4‐Substituted‐2‐naphthols via a Tandem Friedel—Crafts Reaction: A β‐Chlorovinyl Ketone Pathway.
Authors: Kim Hun Young , Oh Kyungsoo
Published: April 2015

The transformation of phenyl acetyl chlorides and asymmetrically disubstituted alkynes results in the regioselective formation of β‐chlorovinyl ketone intermediates offering access to 3,4‐disubstituted‐2‐naphthols.
ChemInform Abstract: Trifluoromethylated Allyl Alcohols: Acid‐Promoted Reactions with Arenes and Unusual ′Dimerization′.
Authors: Kazakova Anna N. , Iakovenko Roman O. , Muzalevskiy Vasiliy M. , Boyarskaya Irina A. , Avdontceva Margarita S. , Starova Galina L. , Vasilyev Aleksander V. , Nenajdenko Valentine G.
Published: April 2015

In the presence of FeCl3 trifluoromethylated allyl alcohols undergo an electrophilic dimerization to indane derivatives.
ChemInform Abstract: Unprecedented Synthesis of Aza‐Bridged Benzodioxepine Derivatives Through a Tandem Rh(II)‐Catalyzed 1,3‐Rearrangement/[3 + 2] Cycloaddition of Carbonyltriazoles.
Authors: Zhang Yong‐Sheng , Tang Xiang‐Ying , Shi Min
Published: April 2015

A Rh(II)‐catalyzed tandem intramolecular cyclization of aromatic aldehydes and ketones having a (1‐sulfonyl‐1,2,3‐triazolyl)methoxy side chain is developed to allow a novel synthesis of the title compounds (II), (IV), and (VI).
ChemInform Abstract: Tunable and Chemoselective Syntheses of Dihydroisobenzofurans and Indanones via Rhodium‐Catalyzed Tandem Reactions of 2‐Triazole‐benzaldehydes and 2‐Triazole‐alkylaryl Ketones.
Authors: Shen Hongjuan , Fu Junkai , Gong Jianxian , Yang Zhen
Published: April 2015

The transformation of 2‐triazolebenzaldehydes and 2‐triazolealkylarylketones with aliphatic or benzylic alcohols affords dihydroisobenzofurans.
ChemInform Abstract: A Catalytic Approach to the Metal‐Free Reaction of Epoxides with Ketene Silyl Acetals for Accessing γ‐Lactones.
Authors: Bonollo Simona , Ahmady Amanollah Zarei , Petrucci Chiara , Marrocchi Assunta , Pizzo Ferdinando , Vaccaro Luigi
Published: April 2015

The simple protocol provides γ‐lactones with high regioselectivities [except for styrene epoxide (II)].