bluuebunny/crossref_metadata_2025 huggingface dataset:
Simultaneous Determination of Co-formulated Matrine and Secnidazole in Suppositories by Reverse Phase High Performance Liquid Chromatography
Authors: Lv Haixia , Ma Suying , Wang Xiao , Shang Xiaojun
Published: July 2013

Purpose: To develop and validate a new, simple, sensitive and accurate high performance liquid chromatographic (HPLC) method for the simulataneous determination of matrine and secnidazole in suppositories.Methods: The method involved using a SinoChoom ODS-BP C18 column (5 ƒÊm, 4.6 mm ~ 200 mm) and mobile phase consisting of  acetonitrile.triethylamine (0.05 %) in 0.025 mol/L KH2PO4 (20:80, v/v).The flow rate was 1 mL/min and detection was monitored at 210 and 311 nm for matrine and secnidazole, respectively. Total run time was 10 min and the column was maintained at 35 oC.Results: The excipients in the suppository did not interfere with the drug peaks. Matrine was eluted at a retention time (RT) of 4.30 min while linearity for the quantification of drug was obtained in the concentration range of 10.0 - 100.0 ƒÊg/mL (r2 = 0.9991). Secnidazole was eluted at a retention time (tr) of 6.69 min and linearity for the quantification of the drug was obtained in the concentration range of 10.0 - 150.0 ƒÊg/mL (r2 = 0.9993). Intra- and inter-day variations were < 1.0 % for both matrine andsecnidazole.Conclusion: The developed HPLC method was validated according to International Conference on Harmonisation (ICH) guidelines and proved to be suitable for the simultaneous determination of matrine and secnidazole in suppositories.Keywords: Matrine, Secnidazole, Suppository, HPLC, Assay
Community Pharmacists’ Perception of the Relevance of Drug Package Insert as Source of Drug Information in Southwestern Nigeria
Authors: Diobi K , Fakeye TO , Adisa R
Published: July 2013

Purpose: To evaluate the opinions of community pharmacists on the usefulness and reliability of drug package inserts (DPI) as drug information source, and necessary modifications needed to improve theircontents.Methods: A prospective cross-sectional study using a pretested questionnaire was administered to sixty-one superintendent community pharmacists (CP) across two cities in southwestern Nigeria. Descriptive statistics was used to summarize the data and evaluate respondents’ opinion. Kruskal-Wallis test was used to evaluate the rank variables with p < 0.05 considered significant.Results: A majority of CP believed that information from DPI was precise and may be helpful in achieving therapeutic success (n = 42; 72.8 %). CP believed there is need for the modification of DPI content with respect to patient-related information (n = 52; 92.8 %) and health provider-relatedinformation (n = 52; 94.5%), non-uniformity of information on the same generic medicines (n = 31; 50.8 %), and ambiguity of content (n = 29; 47.5 %). Years of experience in practice significantly influenced respondents’ perception of precision and satisfaction with DPI as source of information.Conclusions: Community pharmacists in southwestern Nigeria believed that a properly modified drug package insert could be a useful and reliable source of drug information in daily practice.Keywords: Community pharmacist, Drug information, Drug package insert
Simulating river discharge in a snowy region of Japan using output from a regional climate model
Authors: Ma X. , Kawase H. , Adachi S. , Fujita M. , Takahashi H. G. , Hara M. , Ishizaki N. , Yoshikane T. , Hatsushika H. , Wakazuki Y. , Kimura F.
Published: July 2013

Abstract. Snowfall amounts have fallen sharply along the eastern coast of the Sea of Japan since the mid-1980s. Toyama Prefecture, located approximately in the center of the Japan Sea region, includes high mountains of the northern Japanese Alps on three of its sides. The scarcity of meteorological observation points in mountainous areas limits the accuracy of hydrological analysis. With the development of computing technology, a dynamical downscaling method is widely applied into hydrological analysis. In this study, we numerically modeled river discharge using runoff data derived by a regional climate model (4.5-km spatial resolution) as input data to river networks (30-arcseconds resolution) for the Toyama Prefecture. The five main rivers in Toyama (the Oyabe, Sho, Jinzu, Joganji, and Kurobe rivers) were selected in this study. The river basins range in area from 368 to 2720 km2. A numerical experiment using climate comparable to that at present was conducted for the 1980s and 1990s. The results showed that seasonal river discharge could be represented and that discharge was generally overestimated compared with measurements, except for Oyabe River discharge, which was always underestimated. The average correlation coefficient for 10-year average monthly mean discharge was 0.8, with correlation coefficients ranging from 0.56 to 0.88 for all five rivers, whereas the Nash-Sutcliffe efficiency coefficient indicated that the simulation accuracy was insufficient. From the water budget analysis, it was possible to speculate that the lack of accuracy of river discharge may be caused by insufficient accuracy of precipitation simulation.
A novel instrument for measurements of BrO with LED based Cavity-Enhanced Differential Optical Absorption Spectoscopy
Authors: Hoch D. J. , Buxmann J. , Sihler H. , Pöhler D. , Zetzsch C. , Platt U.
Published: July 2013

Abstract. The chemistry of the troposphere and specifically the global tropospheric ozone budget is affected by reactive halogen species like Bromine monoxide (BrO) or Chlorine monoxide (ClO). Especially BrO plays an important role in the processes of ozone destruction, disturbance of NOx and HOx chemistry, oxidation of DMS, and the deposition of elementary mercury. In the troposphere BrO has been detected in polar regions, at salt lakes, in volcanic plumes, and in the marine boundary layer. For a better understanding of these processes field measurements as well as reaction-chamber studies are performed. In both cases instruments with high spatial resolution and high sensitivity are necessary. A Cavity Enhanced Differential Optical Absorption Spectroscopy (CE-DOAS) instrument with an open path measurement cell was designed and applied. For the first time, a CE-DOAS instrument is presented using an UV-LED in the 325–365 nm wavelength range. In laboratory studies, BrO as well as HONO, HCHO, O3, and O4, could be reliable determined at detection limits of 20 ppt for BrO, 9.1 ppb for HCHO, 970 ppt for HONO, and 91 ppb for O3, for five minutes integration time, respectively. The best detection limits were achieved for BrO (11 ppt), HCHO (5.1 ppb), HONO (490 ppt), and O3 (59 ppb) for integration times of 81 min or less. Comparison with established White-System DOAS and O3 monitor demonstrate the reliability of the instrument.
Detection of a plasmaspheric wind in the Earth's magnetosphere by the Cluster spacecraft
Authors: Dandouras I.
Published: July 2013

Abstract. Plumes, forming at the plasmapause and released outwards, constitute a well-established mode for plasmaspheric material release to the Earth's magnetosphere. They are associated to active periods and the related electric field change. In 1992, Lemaire and Shunk proposed the existence of an additional mode for plasmaspheric material release to the Earth's magnetosphere: a plasmaspheric wind, steadily transporting cold plasmaspheric plasma outwards across the geomagnetic field lines, even during prolonged periods of quiet geomagnetic conditions. This has been proposed on a theoretical basis. Direct detection of this wind has, however, eluded observation in the past. Analysis of ion measurements, acquired in the outer plasmasphere by the CIS experiment onboard the four Cluster spacecraft, provide now an experimental confirmation of the plasmaspheric wind. This wind has been systematically detected in the outer plasmasphere during quiet and moderately active conditions, and calculations show that it could provide a substantial contribution to the magnetospheric plasma populations outside the Earth's plasmasphere. Similar winds should also exist on other planets, or astrophysical objects, quickly rotating and having an atmosphere and a magnetic field.
Sea–air CO2 fluxes in the Indian Ocean between 1990 and 2009
Authors: Sarma V. V. S. S. , Lenton A. , Law R. , Metzl N. , Patra P. K. , Doney S. , Lima I. D. , Dlugokencky E. , Ramonet M. , Valsala V.
Published: July 2013

Abstract. The Indian Ocean (44° S–30° N) plays an important role in the global carbon cycle, yet remains one of the most poorly sampled ocean regions. Several approaches have been used to estimate net sea–air CO2 fluxes in this region: interpolated observations, ocean biogeochemical models, atmospheric and ocean inversions. As part of the RECCAP (REgional Carbon Cycle Assessment and Processes) project, we combine these different approaches to quantify and assess the magnitude and variability in Indian Ocean sea–air CO2 fluxes between 1990 and 2009. Using all of the models and inversions, the median annual mean sea–air CO2 uptake of −0.37 ± 0.06 Pg C yr–1, is consistent with the −0.24 ± 0.12 Pg C yr–1 calculated from observations. The fluxes from the Southern Indian Ocean (18° S–44° S; −0.43 ± 0.07 Pg C yr–1) are similar in magnitude to the annual uptake for the entire Indian Ocean. All models capture the observed pattern of fluxes in the Indian Ocean with the following exceptions: underestimation of upwelling fluxes in the northwestern region (off Oman and Somalia), over estimation in the northeastern region (Bay of Bengal) and underestimation of the CO2 sink in the subtropical convergence zone. These differences were mainly driven by a lack of atmospheric CO2 data in atmospheric inversions, and poor simulation of monsoonal currents and freshwater discharge in ocean biogeochemical models. Overall, the models and inversions do capture the phase of the observed seasonality for the entire Indian Ocean but over estimate the magnitude. The predicted sea–air CO2 fluxes by Ocean BioGeochemical Models (OBGM) respond to seasonal variability with strong phase lags with reference to climatological CO2 flux, whereas the atmospheric inversions predict an order of magnitude higher seasonal flux than OBGMs. The simulated interannual variability by the OBGMs is weaker than atmospheric inversions. Prediction of such weak interannual variability in CO2 fluxes by atmospheric inversions was mainly caused by lack of atmospheric data in the Indian Ocean. The OBGM models suggest a small strengthening of the sink over the period 1990–2009 of −0.01 Pg C decade–1. This is inconsistent with the observations in the southwest Indian Ocean that shows the growth rate of oceanic pCO2 was faster than the observed atmospheric CO2 growth, a finding attributed to the trend of the Southern Annual Mode (SAM) during the 1990s.
Sedimentary and atmospheric sources of iron around South Georgia, Southern Ocean: a modelling perspective
Authors: Borrione I. , Aumont O. , Nielsdóttir M. C. , Schlitzer R.
Published: July 2013

Abstract. In high-nutrient low-chlorophyll waters of the western Atlantic sector of the Southern Ocean, an intense phytoplankton bloom is observed annually north of South Georgia, most likely due to an enhanced supply of the limiting micronutrient iron. Shallow sediments and atmospheric dust deposition are believed to be the main iron sources. However, their relative importance is still unclear and in the South Georgia region have yet not been ascertained because iron measurements are very few. In this study, we use austral summer dissolved iron (dFe) data around South Georgia (January and February 2008) with a coupled regional hydrodynamic and biogeochemical model to investigate natural iron fertilization around the island. The biogeochemical component of the model includes an iron cycle, where sediments and dust deposition are the sources of iron to the ocean. The model captures the characteristic flow patterns around South Georgia, hence simulating a large phytoplankton bloom to the north, i.e., downstream, of the island. Modelled dFe concentrations agree well with observations (mean difference and root mean square errors of ~0.02 nM and ~0.81 nM) and form a large plume to the north of the island that extends eastwards for more than 800 km. In agreement with observations, highest dFe concentrations are located along the coast and decrease with distance from the island. Sensitivity tests indicate that most of the iron measured in the main bloom area originates from the coast and the very shallow shelf-sediments (depths < 20 m) while dust deposition plays a minor role, with almost no effects on surface chlorophyll a concentrations. Iron sources such as run-off not represented explicitly in the model, but that likely contribute to the iron plumes observed around South Georgia, are also discussed together with the potential effects their temporal variability may have on the system.
Separating the effects of changes in land cover and climate: a hydro-meteorological analysis of the past 60 yr in Saxony, Germany
Authors: Renner M. , Brust K. , Schwärzel K. , Volk M. , Bernhofer C.
Published: July 2013

Abstract. Understanding and quantifying the impact of changes in climate and in land use/land cover on water availability is a prerequisite to adapt water management; yet, it can be difficult to separate the effects of these different impacts. Here, we illustrate a separation and attribution method based on a Budyko framework. We assume that ET is limited by the climatic forcing of precipitation P and evaporative demand E0, but modified by land surface properties. Impacts of changes in climate (i.e. E0/P) or land-surface changes on ET alter the two dimensionless measures describing relative water ET/P and energy partitioning ET/E0, which allows us to separate and quantify these impacts. We use the separation method to quantify the role of environmental factors on ET using 68 small to medium range river basins covering the greatest part of Saxony within the period of 1950-2009. The region can be considered a typical Central European landscape with considerable anthropogenic impacts. In the long term, most basins are found to follow the Budyko curve which we interpret as a result of the strong interactions of climate, soils and vegetation. However, two groups of basins deviate. Agriculturally dominated basins at lower altitudes exceed the Budyko curve while a set of high altitude, forested basins fall well below. When visualizing the decadal dynamics on the relative partitioning of water and energy the impacts of climatic and land surface changes become apparent. After 1960 higher forested basins experienced large land surface changes which show that the air pollution driven tree damages have led to a decline of annual ET in the order of 38%. In contrast, lower, agricultural dominated areas show no significant changes during that time. However, since the 1990s when effective mitigation measures on industrial pollution have been established, the apparent brightening and regrowth has resulted in a significant increase of ET across most basins. In conclusion, data on both, the water and the energy balance is necessary to understand how long-term climate and land cover control evapotranspiration and thus water availability. Further, the detected land surface change impacts are consistent in space and time with independent forest damage data and thus confirm the validity of the separation approach.
Advancing catchment hydrology to deal with predictions under change
Authors: Ehret U. , Gupta H. V. , Sivapalan M. , Weijs S. V. , Schymanski S. J. , Blöschl G. , Gelfan A. N. , Harman C. , Kleidon A. , Bogaard T. A. , Wang D. , Wagener T. , Scherer U. , Zehe E. , Bierkens M. F. P. , Di Baldassarre G. , Parajka J. , van Beek L. P. H. , van Griensven A. , Westhoff M. C. , Winsemius H. C.
Published: July 2013

Abstract. Throughout its historical development, hydrology as an engineering discipline and earth science has relied strongly on the assumption of long-term stationary boundary conditions and system configurations, which allowed for simplified and sectoral descriptions of the dynamics of hydrological systems. However, in the face of rapid and extensive global changes (of climate, land use etc.) which affect all parts of the hydrological cycle, the general validity of this assumption appears doubtful. Likewise, so does the application of hydrological concepts based on stationarity to questions of hydrological change. The reason is that transient system behaviours often develop through feedbacks between the system constituents, and with the environment, generating effects that could often be neglected under stationary conditions. In this context, the aim of this paper is to present and discuss paradigms and theories potentially helpful to advancing hydrology towards the goal of understanding and predicting hydrological systems under change. For the sake of brevity we focus on catchment hydrology. We begin with a discussion of the general nature of explanation in hydrology and briefly review the history of catchment hydrology. We then propose and discuss several perspectives on catchments: as complex dynamical systems, self-organizing systems, co-evolving systems and open dissipative thermodynamic systems. We discuss the benefits of comparative hydrology and of taking an information-theoretic view of catchments, including the flow of information from data to models to predictions. In summary, we suggest that the combination of these closely related perspectives can serve as a paradigm for the further development of catchment hydrology to address predictions under change.
Estimation of volume changes of mountain glaciers from ICESat data: an example from the Aletsch Glacier, Swiss Alps
Authors: Kropáček J. , Neckel N. , Bauder A.
Published: July 2013

Abstract. Worldwide estimation of recent changes in glacier volume is challenging, but becomes more feasible with the help of present and future remote sensing missions. NASA's Ice Cloud and Elevation Satellite (ICESat) mission provides accurate elevation estimates derived from the two way travel time of the emitted laser pulse. In this study two different methods were employed for derivation of surface elevation changes from ICESat records on example of the Aletsch Glacier. A statistical approach relies on elevation differences of ICESat points to a reference DEM while an analytical approach compares spatially similar ICESat tracks. Using the statistical approach, in the upper and lower parts of the ablation area, the surface lowering was found to be from −2.1 ± 0.15 m yr−1 to −2.6 ± 0.10 m yr−1 and from −3.3 ± 0.36 m yr−1 to −5.3 ± 0.39 m yr−1, respectively, depending on the DEM used. Employing the analytical method, the surface lowering in the upper part of the ablation area was estimated as −2.5 ± 1.3 m yr−1 between 2006 and 2009. In the accumulation area both methods revealed no significant trend. The trend in surface lowering derived by the statistical method allows an estimation of the mean mass balance in the period 2003–2009 assuming constant ice density and a linear change of glacier surface lowering with altitude in the ablation area. The resulting mass balance was validated by a comparison to another geodetic approach based on the subtraction of two DEMs for the years 2000 and 2009. We conclude that ICESat data is a valid source of information on surface elevation changes and on mass balance of mountain glaciers.
Jumps in Oil Prices: The Role of Economic News
Authors: Elder John , Miao Hong , Ramchander Sanjay
Published: July 2013

Previous research has been unable to identify a strong link between crude oil prices and economic news. We reexamine this relationship using high frequency intraday data and relatively new methodology to estimate jumps in oil prices. We find a surprisingly strong correspondence between high frequency jumps in oil prices and the arrival of new economic information, with the largest jumps tending to be preceded identifiable economic news. These results indicate that oil prices respond very rapidly to new economic data in ways that appear consistent with economic theory, and also suggest that economic news, rather than speculation unrelated to the economic environment, drives jumps in oil prices.
The Role of Speculation in Oil Markets: What Have We Learned So Far?
Authors: Fattouh Bassam , Kilian Lutz , Mahadeva Lavan
Published: July 2013

A popular view is that the surge in the real price of oil during 2003-08 cannot be explained by economic fundamentals, but was caused by the increased financialization of oil futures markets, which in turn allowed speculation to become a major determinant of the spot price of oil. This interpretation has been driving policy efforts to tighten the regulation of oil derivatives markets. This survey reviews the evidence supporting this view. We identify six strands in the literature and discuss to what extent each sheds light on the role of speculation. We find that the existing evidence is not supportive of an important role of speculation in driving the spot price of oil after 2003. Instead, there is strong evidence that the co-movement between spot and futures prices reflects common economic fundamentals rather than the financialization of oil futures markets.
The Role of Financial Speculation in Driving the Price of Crude Oil
Authors: Alquist Ron , Gervais Olivier
Published: July 2013

As financial firms have increased their positions in the oil futures market during the past ten years, oil prices have increased dramatically as well. The coincidence of these two events has led some observers to argue that financial speculation caused the oil-price increases. Yet several arguments cast doubt on the validity of this claim. For example, although the quantity of oil implied by the number ofopen futures contracts is much larger than U.S. daily oil consumption, comparing these two statistics is misleading because not all paper oil is immediately deliverable. In addition, changes in financial firms’ positions do not predict oil-price changes, but oil-price changes predict changes in positions. Other explanations for the oil-price increases include macroeconomic fundamentals such as increased demand from emerging Asia. Of these explanations, the most consistent with the facts relates the oil-price increases to a series of positive demand shocks emanating from emerging Asia.
Cyclic Alkyl(aryl)boranes for 1,1-Carboboration of Monoalkynyltin Compounds
Authors: Wrackmeyer Bernd , Thoma Peter , Milius Wolfgang
Published: July 2013

Two cyclic alkyl(aryl)boranes, a 1-bora-indane derivative 1, and a tricyclic derivative 4, containing the boron atom in a six-membered ring, were structurally characterized by NMR techniques in solution. The solid-state structure of the 1-bora-indane 1 was determined by X-ray crystallography. The reactivity of these cyclic alkyl(aryl)boranes towards monoalkynyltin compounds, Me3Sn-C≡C-Me and Me3Sn-C C-Fc (Fc=ferrocenyl), was studied using multinuclear magnetic resonance methods (1H, 11B, 13C, 119Sn NMR). Novel alkenylboranes were formed by 1,1-carboboration reactions. This process involves an expansion of both five- and six-membered rings. Insertion into the respective B-C(aryl) bond was preferred with high selectivity. In the case of the six-membered ring in 4, the ring expansion to seven-membered rings proved to be readily reversible, and the thermodynamically stable reaction products were formed by ring contraction and concomitant transfer of the exocyclic B-nPr group
Synthesis and Characterization of Imidazolium Perrhenate Ionic Liquids
Authors: Yue Shuang , Fang Da-Wei , Li Jun , Zang Shu-Liang , Zhou Ming-Dong , Zhang Bo , Markovits Iulius I. E. , Cokoja Mirza , Kühn Fritz E.
Published: July 2013

A series of air- and water-stable imidazolium perrhenate-based room-temperature ionic liquids [(RT)ILs] of the type [Cnmim][ReO4] (Cnmim = 1-CnH2n+1-3-methylimidazolium, n = 2, 4, 5, 6, 8, 10, 12) have been synthesized and characterized by 1H and 13C NMR spectroscopy, IR spectroscopy, electrospray ionization mass spectrometry (ESI-MS), and elemental analysis (EA). The effect of the variation of the alkyl chain length on physical properties such as melting point, thermal stability, density, and conductivity was examined
Ferromagnetism and the Formation of Interlayer As2 Dimers in Ca(Fe1-xNix)2As2
Authors: Pobel Roman , Frankovsky Rainer , Johrendt Dirk
Published: July 2013

The compounds Ca(Fe1-xNix)2As2 with the tetragonal ThCr2Si2-type structure (space group I4=mmm) show a continuous transition of the interlayer As-As distances from a non-bonding state in CaFe2As2 (dAs-As =313 pm) to single-bonded As2 dimers in CaNi2As2 (dAs-As =260 pm). Magnetic measurements have revealed weak ferromagnetism which develops near the composition Ca(Fe0:5Ni0:5)2As2, while the compounds with lower and higher nickel concentrations are both Pauli-paramagnetic. DFT band structure calculations have shown that the As2 dimer formation is a consequence of weaker metal-metal bonding in the MAs4/4 layers (M=Fe1-xNix) of the Ni-rich compounds, and depends not on depopulation or shift of As-As σ antibonding states as previously suggested. Our results also show that the ferromagnetism of Ca(Fe0:5Ni0:5)2As2 and related compounds like SrCo2(Ge0:5P0:5)2 is not as recently suggested induced by dimer breaking, but arises from the high density of states generated by the transition metal 3d bands near the Fermi level without contribution from dimers
Synthesis, Crystal Structures and Polymorphism of New Cadmium and Zinc Thio- and Selenocyanato Coordination Compounds with 4-Acetylpyridine as N-Donor Ligand
Authors: Werner Julia , Jess Inke , Näther Christian
Published: July 2013

Reactions of cadmium(II) thio- and selenocyanate with 4-acetylpyridine in different molar ratios and in different solvents always lead to the formation of compounds of composition Cd(NCS)2(4- acetylpyridine)2 (Cd1-I) and Cd(NCSe)2(4-acetylpyridine)2 (Cd2). Both compounds are isotypic and crystallize in the monoclinic space group C2/c. In their crystal structures the Cd cations are coordinated by two N-bonded 4-acetylpyridine ligands as well as two N- and two S/Se-bonded thio- or selenocyanato anions within a slightly distorted octahedral geometry. The Cd cations are linked into chains by pairwise μ-1,3-coordinating thio- or selenocyanato anions. In one reaction single crystals of a second polymorphic modification of composition Cd(NCS)2(4-acetylpyridine)2 (Cd1-II) were obtained by accident. This modification crystallizes monoclinically in space group P21/c, exhibits the same topology of the coordination network as in Cd1-I and Cd2 but a different arrangement of the chains in the crystal. Similar investigations with Zn(II) have revealed that only one compound of composition Zn(NCS)2(4-acetylpyridine)2 can be prepared that crystallizes in the triclinic space group P1. Its structure consists of discrete complexes in which the Zn(II) cations are tetrahedrally coordinated. A corresponding selenocyanato coordination compound could not be prepared
Molecular and Crystal Structure of Chlorido[2-(N,N,N',N'- tetramethylamidinio)ethynido]silver
Authors: Weingärtner Werner , Maas Gerhard
Published: July 2013

The solid-state structure of chlorido[2-(N,N,N',N'-tetramethylamidinio)ethynido]silver (3), obtained by C(sp)-metalation of N,N,N',N'-tetramethyl-propiolamidinium chloride with silver(I) oxide, has been determined by X-ray diffraction analysis. A comparison of bond lengths in the propiolamidinium moiety with those of the two genuine propiolamidinium salts 4 and 5, as well as with data for the isolated N,N,N',N'-tetramethyl-propiolamidinium cation obtained by quantum-chemical calculations, has been made. It can be concluded that complex 3 is better described as a (tetramethylamidinio) ethynyl than as a 3,3-bis(dimethylamino)allenylidene silver complex
Review. Regioselective Functionalization of Pyridines using a Directed Metalation or a Halogen/Metal Exchange
Authors: Manolikakes Sophia M. , Barl Nadja M. , Sämann Christoph , Knochel Paul
Published: July 2013

This review describes the various ways of functionalizing the pyridine scaffold using either directed metalation or halogen/metal exchange. Deprotonation can be accomplished with different lithium amides or alkyllithium reagents at low temperature. Milder conditions and higher functional group tolerance can be achieved by using ate-bases with different metals (Cd, Mg, Zn) or TMP (2,2,6,6- tetramethylpiperidyl) metal reagents (metal=Mg, Zn, Zr). With alkyllithium reagents it is also possible, by carefully adjusting the reaction conditions, to perform bromine/lithium exchange reactions. Organomagnesium reagents, like iPrMgX (X=Br, Cl LiCl), may be used for exchanging more sensitive iodinated or brominated pyridines
Preparation of CaCO3 and CaO Replicas Retaining the Hierarchical Structure of SpruceWood
Authors: Klaithong Somruedee , Opdenbosch Daniel Van , Zollfrank Cordt , Plank Johann
Published: July 2013

The principal structural characteristics of softwood (spruce) were replicated in CaCO3 and CaO on various levels of hierarchy from the macroscopic to the submicron scale. Positive replicas were obtained by infiltrating pretreated softwood templates with a Ca(OCOOCH3)2 precursor solution which hydrolyzed into CaCO3 nanoparticles. They reproduce the hierarchical porous structure of the wood template. Calcination at temperatures from 350 to 900 °C yields calcite as the main polymorph. Mechanical stability of the replica is optimized when the specimen is calcined at 900 °C
Review. Fluorescence Microscopy Studies of Porous Silica Materials
Authors: Rühle Bastian , Davies Melari , Bein Thomas , Bräuchle Christoph
Published: July 2013

In this article, we discuss how fluorescence microscopy techniques are used to investigate important characteristics of porous silica materials. We start with a discussion of the synthesis, formation mechanism and functionalization of these materials. We then give an introduction to single molecule microscopy and show how this technique can be used to gain deeper insights into some defining properties of porous silica, such as pore structure, host-guest interactions and diffusion dynamics. We also provide examples from the literature demonstrating how fluorescence microscopy is used for elucidating important aspects of porous silica materials and heterogeneous catalysis, e. g. diffusion properties, reactivity, morphology, intergrowth, accessibility, and catalyst deactivation. Finally, a short outlook on the scope of porous silica hosts in drug delivery applications is given
Coordination Chemistry of Polynitriles, I. Syntheses and Crystal Structures of [Ag(PCC)(DMF)], [Ni(DMF)6](PCC)2 and [Co(DMF)6](PCC)2 (PCC = [C5(CN)5]-, DMF = N,N-Dimethylformamide) [1]
Authors: Sünkel Karlheinz , Reimann Dietmar
Published: July 2013

Recrystallization of silver pentacyanocyclopentadienide Ag[C5(CN)5] from N,N-dimethylformamide (DMF) gives the polymeric 1:1 complex [Ag{C5(CN)5}(DMF)] (1). The Ag+ cation is coordinated by three N atoms of three different [C5(CN)5]- anions and two O atoms of two DMF molecules. Each [C5(CN)5]- is coordinated via three neighboring CN groups to three different Ag+ ions, while each DMF molecule bridges two Ag+ ions via its O atom. Treatment of NiCl2 6H2O, CoCl2 6H2O or ZnCl2 with Ag[C5(CN)5] in DMF gives the DMF complexes [M(DMF)6][C5(CN)5]2 (M=Ni, 2; Co, 3; Zn, 4). The complexes 2 and 3 were characterized by X-ray diffraction and show octahedral [M(DMF)6]2+ cations with O-coordinated DMF molecules. The [C5(CN)5]- anions show ideal pentagonal symmetry
Novel Tin(IV) Complexes with the Hybrid Guanidine Ligand DMEGqu
Authors: Jesser Anton , Vieira Ines dos Santos , Herres-Pawlis Sonja
Published: July 2013

Novel Sn(IV) complexes with the guanidine-quinoline hybrid ligand DMEGqu are reported. With SnCl4, SnBr4, Me2SnCl2, Me2SnBr2, and the 3,5-di-tert-butyl-catecholate coligand complexes with different donor sets were synthesized. Four of these tin compounds have been modelled by density functional theory. Additionally, a tetranuclear Sn(IV) oxocluster with a novel structure motif, a distorted hetero-adamantane with bridging oxido and hydroxido ligands, is presented
Nucleophilic Reactivities of Schiff Bases
Authors: Maji Biplab , Mayr Herbert
Published: July 2013

The nucleophile-specific parameters N and sN, as defined by the linear free energy relationship log k = sN(N+E) (J. Am. Chem. Soc. 2001, 123, 9500 - 9512), were determined for five imines 1a-e by studying the kinetics of their reactions with benzhydrylium ions in dichloromethane solution at 20 °C. These parameters allowed us to include representative Schiff bases into our comprehensive nucleophilicity scale and compare their reactivities with those of other N-nucleophiles
Temporary expansion to shelf depths rather than an onshore-offshore trend: the shallow-water rise and demise of the modern deep-sea brittle star family Ophiacanthidae (Echinodermata: Ophiuroidea)
Authors: Thuy Ben
Published: July 2013

Hypotheses on the age and possible antiquity of the modern deep-sea fauna put forward to date almost all agree on the assumption that the deep-sea fauna is largely the result of colonisation from shallow-water environments. Here, the fossil record of the Ophiacanthidae, a modern deep-sea brittle star family with extensive fossil occurrences at shelf depths, is systematically traced against a calibrated phylogeny. Several lines of evidence suggest that the Ophiacanthidae originated and greatly diversified in the deep sea, with most extant clades having diverged by the end of the Triassic at the latest. During the Jurassic, the family temporarily invaded shelf environments, attaining relative abundances and diversities comparable to those found in coeval and modern deep-sea settings, and gradually declined in abundance subsequently, to become largely restricted to the deep-sea again. The pattern of temporary expansion to shelf environments suggested here underpins the potential of deep-sea environments to contribute significantly to shallow-water biodiversity; an aspect that has mostly been neglected so far. It is speculated that the large-scale ophiacanthid invasion of shelf environments around the Triassic-Jurassic boundary was initiated by a change from thermohaline to halothermal circulation, attenuating the thermal stratification of the water column and thus providing opportunities for enhanced vertical migration of marine taxa.
Potencial energético da madeira de espécies oriundas de plano de manejo florestal no Estado do Rio Grande do Norte
Authors: Santos Rosimeire Cavalcante dos , Carneiro Angélica de Cássia Oliveira , Pimenta Alexandre Santos , Castro Renato Vinícius Oliveira , Marinho Itaragil Venâncio , Trugilho Paulo Fernando , Alves Isabel Cristina Nogueira , Castro Ana Flávia Neves Mendes
Published: July 2013

http://dx.doi.org/10.5902/198050989293O objetivo do trabalho foi avaliar o potencial energético das madeiras de espécies sob plano de manejo florestal provenientes da região do Seridó, no estado do Rio Grande do Norte. Utilizou-se na pesquisa, madeiras das espécies Jurema-preta, Pereiro, Marmeleiro, Catingueira, Mororó, Imburana, Jurema-branca e Mofumbo, aos 20 anos de idade, originadas da fazenda Dominga no município de Caicó/RN. Foram realizadas na madeira, as análises da densidade básica, teores de materiais voláteis, cinzas e carbono fixo, poder calorífico superior, composição química elementar e relações carbono/nitrogênio (C/N) e carbono/ hidrogênio (C/H). Adicionalmente, estimou-se a quantidade de energia produzida em kW.h.m-3 e em kW.h.ha-1 para todas as espécies. O experimento foi realizado segundo um delineamento inteiramente casualizado com oito tratamentos (espécies), quatro repetições (árvores–amostra), totalizando 32 unidades amostrais. Houve diferença significativa, a 5 % de significância, entre os tratamentos para todas as variáveis analisadas, exceto para a porcentagem de hidrogênio e relação C/H. Conclui-se que a madeira de Mororó apresenta alto potencial energético, e juntamente com a Jurema-preta, maior geração de energia por m3, além de proporcionar maior economia para uma mesma produtividade. O potencial energético da madeira de Jurema-preta se destaca entre as espécies estudadas. A madeira de Pereiro se destaca na produção de energia por hectare. As madeiras de Jurema-branca e Marmeleiro são indicadas como potenciais para queima direta. A madeira de Imburana não é recomendada para a geração de energia.
Predicción bayesiana de parámetros genéticos en clones de Eucalyptus globulus bajo condiciones de suplemento hídrico
Authors: Mora Freddy , Rubilar Rafael , Emhart Veronica Ingrid , Saavedra Javier
Published: July 2013

http://dx.doi.org/10.5902/198050989297Se realizó un análisis Bayesiano de parámetros genéticos del crecimiento en 29 clones de Eucalyptus globulus de doce meses de edad, en el sur de Chile. Se consideraron dos condiciones ambientales contrastantes en cuanto a la disponibilidad hídrica: 1. Sin irrigación, y 2. Las plantas se irrigaron con un sistema localizado de riego. Para el análisis Bayesiano se utilizó el algoritmo de Gibbs en un modelo de interacción clon-ambiente. Los valores de heredabilidad fueron altos en la condición de riego (moda a posteriori de H2=0,41, 0,36 y 0,39 para la altura, diámetro y área basal, respectivamente), en tanto que en la situación sin riego, los valores de las heredabilidades fueron significativamente más bajos; confirmado por medio de los intervalos de credibilidad Bayesianos (95 % de probabilidad). La moda a posteriori de la correlación genética entre sitios fue positiva y alta para las tres características (r=0,7, 0,65 y 0,8, para altura, diámetro y área basal, respectivamente), y de acuerdo al intervalo de credibilidad, esta correlación fue estadísticamente diferente de cero, indicando una interacción no significativa.
Comparação fotointerpretativa entre aerofoto e imagem de satélite
Authors: Peluzio Telma Machado de Oliveira , Santos Alexandre Rosa dos , Fiedler Nilton César , Bauer Maristela de Oliveira , Garcia Giovanni de Oliveira , Simão João Batista Pavesi , Peluzio João Batista Esteves
Published: July 2013

http://dx.doi.org/10.5902/198050989298Este estudo objetivou avaliar o uso de diferentes metodologias na determinação do uso e ocupação da terra utilizando aerofotos digitais, com resolução espacial de 1 m (cenário 01) e imagens de satélite, com resolução espacial de 0,5 m (cenário 02), fotointerpretadas em tela, na escala cartográfica de 1:2.000, da bacia hidrográfica do córrego Horizonte, Alegre-ES. Utilizaram-se os índices de desempenho global e índice Kappa para determinação do erro médio entre os cenários e teste t a 5 % de probabilidade para avaliar o grau de significância no processo de fotointerpretação entre os cenários 01 e 02. Foram identificadas 27 classes de uso da terra para os cenários 01 e 02. As classes de pastagem (599,62 e 442,43 ha) e fragmento florestal (319,45 e 258,07 ha) respectivamente, ocupando maiores áreas nos dois cenários, compondo 69,80 % para o cenário 01 e 53,04 % para o cenário 02 das áreas totais. Verificou-se uma variação positiva do DG em 6,67 % do cenário 01 em relação ao cenário 02. Entretanto o K demonstra que o cenário 02 possui uma menor taxa entre os erros de omissão e comissão em 2,09 %, não apresentado significância pela análise estatística em nível de 5 % pelo teste t.
Concise Review: Immunological Properties of Ocular Surface and Importance of Limbal Stem Cells for Transplantation
Authors: Shaharuddin Bakiah , Ahmad Sajjad , Meeson Annette , Ali Simi
Published: July 2013

Cornea transplantation has been considered to be different from other solid organ transplantation because of the assumed immune-privileged state of the anterior chamber of the eye. Three major lines of thought regarding the molecular mechanisms of immune privilege in the eye are as follows: (a) anatomical, cellular, and molecular barriers in the eye; (b) anterior chamber-associated immune deviation; and (c) immunosuppressive microenvironment in the eye. However, cornea transplants suffer allograft rejection when breached by vascularization. In recent developments, cellular corneal transplantation from cultivated limbal epithelial cells has shown impressive advances as a future therapy. The limbal stem cell niche contains stem cells that promote proliferation and migration and have immunosuppressive mechanisms to protect them from immunological reactions. Limbal stem cells are also noted to display an enhanced expression of genes for the antiapoptotic proteins, a property that is imperative for the survival of transplanted tissues. Further investigation of the molecular mechanisms regulating the immune regulation of limbal stem cells is relevant in the clinical setting to promote the survival of whole corneal and limbal stem cell transplantation.
Plastic Fantastic: Schwann Cells and Repair of the Peripheral Nervous System
Authors: Kim Haesun A. , Mindos Thomas , Parkinson David B.
Published: July 2013

Repair in the peripheral nervous system (PNS) depends upon the plasticity of the myelinating cells, Schwann cells, and their ability to dedifferentiate, direct axonal regrowth, remyelinate, and allow functional recovery. The ability of such an exquisitely specialized myelinating cell to revert to an immature dedifferentiated cell that can direct repair is remarkable, making Schwann cells one of the very few regenerative cell types in our bodies. However, the idea that the PNS always repairs after injury, in contrast to the central nervous system, is not true. Repair in patients after nerve trauma can be incredibly variable, depending on the site and type of injury, and only a relatively small number of axons may fully regrow and reinnervate their targets. Recent research has shown that it is an active process that drives Schwann cells back to an immature state after injury and that this requires activity of the p38 and extracellular-regulated kinase 1/2 mitogen-activated protein kinases, as well as the transcription factor cJun. Analysis of the events after peripheral nerve transection has shown how signaling from nerve fibroblasts forms Schwann cells into cords in the newly generated nerve bridge, via Sox2 induction, to allow the regenerating axons to cross the gap. Understanding these pathways and identifying additional mechanisms involved in these processes raises the possibility of both boosting repair after PNS trauma and even, possibly, blocking the inappropriate demyelination seen in some disorders of the peripheral nervous system.
Contribuições para a gestão territorial dos riscos associados à atividade petrolífera
Authors: Gonçalves Felipe Pinto
Published: July 2013

Considerando que a crescente complexidade da organização técnica e espacial da atividade petrolífera presente no estado do Espírito Santo atribui novas demandas de gestão territorial para os governos municipais capixabas, este artigo aborda a problemática dos riscos econômicos e tecnológicos associados a tais atividades. Com base na avaliação de instrumentos como a classificação de usos do solo e o zoneamento do uso e ocupação do solo são discutidas as possibilidades de inserção dos riscos nas políticas municipais de ordenamento do território.
A Reforma Teológica, Bernhardt Varenius e a constituição da Ciência Geográfica
Authors: Vitte Antonio Carlos
Published: July 2013

O artigo tem como objetivo demonstrar a relação entre ciência e religião que foi de grande importância para o desenvolvimento de uma concepção mecânica da natureza do século XVII marcado pela Reforma Protestante. Esta reforma resultou na profanação da natureza, a formação de uma concepção mecânica da mesma, além de influenciar a imaginação e a prática, viabilizando a construção do telescópio e do microscópio, juntamente com as inovações na química e na medicina. É neste contexto que o trabalho geográfico de Bernhardt Varenius inaugurou a modernidade no pensamento geográfico,na medida em que representou o primeiro pensamento que demonstrou empiricamente a validade dos trabalhos de Galileu Galilei, Kepler e Descartes. Varenius entendeu a superfície da superfície da Terra como um conjunto coordenado de áreas diferentes, onde cada áre-região era o produto de um cruzamento complexo entre religião, cultura e natureza. Se em um primeiro momento Varenius geometrizou a superfície a Terra, a sua geografia trouxe a importância de entender o espaço como uma conexão interescalar e fluida, abrindo assim perspectivas para a abordagem kantiana e humbodtiana de geografia e paisagem geográfica.
A situação da economia do Espírito Santo no início do século XXI: um estado desenvolvido e periférico?
Authors: Bertochi Caçador Sávio , Antonio Grassi Robson
Published: July 2013

O Espírito Santo é hoje um dos estados mais desenvolvidos do Brasil, o que pode ser verificado pelos seus indicadores econômicos e sociais quando comparados aos das outras unidades da federação, e os dados mostram que o modelo de crescimento econômico puxado pela produção de commodities foi decisivo neste processo. Porém, a análise de dados de ciência, tecnologia e inovação (CT&I) mostra que o estado ainda é uma economia periférica em termos de geração de conhecimento e da sua incorporação ao processo produtivo. O objetivo do artigo é mostrar este caráter contraditório da evolução recente da economia capixaba (uma economia com indicadores que revelam ao mesmo tempo certo grau de desenvolvimento socioeconômico e inserção periférica na economia brasileira), e discutir as perspectivas futuras do Espírito Santo, a partir do papel decisivo que políticas públicas nas áreas de CT&I assumem na atual Era do Conhecimento e ao mesmo tempo em que ficam claros os limites ambientais e de ocupação do espaço que o atual perfil produtivo do estado (voltado essencialmente para a produção de commodities) significa.
Transformações urbanas sob os efeitos dos processos de globalização: os casos de Vitória-ES-Brasil e de Tete-Moçambique-África
Authors: Zorzal e Silva Marta
Published: July 2013

O artigo trata das mudanças econômicas e sociais e seus efeitos na reestruturação da espacialidade urbana em virtude de investimentos externos em escala global nos espaços locais. Focaliza esses processos nas economias periféricas dos países do eixo Sul-Sul, que estão sendo impactados de formas distintas pelos processos de globalização. Toma como referente empírico dois espaços locais, aparentemente, muito distintos e distantes no tempo e no espaço – Vitória-Espírito Santo-Brasil-América do Sul e Tete-Província de Tete-Moçambique-África – mas que guardam certa similaridade em termos de processos de mudanças em escala global.
A Instalação do Campus Universitário Alaor de Queiroz Araújo e as Consequências sobre o Manguezal do Entorno
Authors: Fernandes Jorge , Do Vale Claudia Câmara
Published: July 2013

Pretende-se mostrar como ocorreu o processo de ocupação da área onde foi instalado o Campus Universitário Alaor de Queiroz Araújo, mais conhecido como “Campus de Goiabeiras” – Universidade Federal do Espírito Santo (UFES) e as consequências sobre o manguezal do entorno. O Campus possui dimensão atual equivalente a 1.567.545 m² e se encontra localizado na região norte do município de Vitória/ES, entre o canal da Passagem e a Avenida Fernando Ferrari. A pesquisa realizada indicou que a ocupação da área resultou na perda de 211.250 m² de manguezal, decorrente dos aterros efetuados inicialmente para adequar o espaço físico destinado à construção do referido Campus e depois para a ampliação da Avenida Fernando Ferrari, finalizada em 2010. Visa também esse artigo apresentar a problemática da entrada de substâncias nocivas oriundas do lançamento de efluentes em diversos pontos existentes no entorno imediato da área.