bluuebunny/crossref_metadata_2025 huggingface dataset:
More potential in statistical analyses of event‐related potentials: a mixed regression approach
Authors: Vossen Helen , Van Breukelen Gerard , Hermens Hermie , Van Os Jim , Lousberg Richel
Published: August 2011

Despite many developments in the methods of event‐related potentials (ERPs), little attention has gone out to the statistical handling of ERP data. Trials are often averaged, and univariate or repeated measures of analysis of variance (ANOVA) are used to test hypotheses. The aim of this study was to introduce mixed regression to ERP research and to demonstrate advantages associated with this method. Eighty‐five healthy subjects received electrical pain stimuli with simultaneous electroencephalography (EEG) registration. Analyses first showed that results obtained with mixed regression analyses are highly comparable to those using repeated measures of ANOVA. Second, important advantages of the mixed regression technique were demonstrated by allowing the inclusion of persons with missing data, single trial analysis, non‐linear time effects, time × person effects (random slope effects) and a within‐subject covariate. Among others, the results showed a strong trial (habituation) effect, which contraindicates the common procedure of averaging of trials. Furthermore, the regression coefficients for intensity and trial varied significantly between persons, indicating individual differences in the effect of intensity and trial on the ERP amplitude. In conclusion, using mixed regression analysis as a statistical technique in ERP research will advance the science of unravelling mechanisms underlying ERP data. Copyright © 2011 John Wiley & Sons, Ltd.
Imaging pH with hyperpolarized 13C
Authors: Gallagher Ferdia A. , Kettunen Mikko I. , Brindle Kevin M.
Published: August 2011

pH is a fundamental physiological parameter that is tightly controlled by endogenous buffers. The acid–base balance is altered in many disease states, such as inflammation, ischemia and cancer. Despite the importance of pH, there are currently no routine methods for imaging the spatial distribution of pH in humans. The enormous gain in sensitivity afforded by dynamic nuclear polarization (DNP) has provided a novel way in which to image tissue pH using MR, which has the potential to be translated into the clinic. This review explores the advantages and disadvantages of current pH imaging techniques and how they compare with DNP‐based approaches for the measurement and imaging of pH with hyperpolarized 13C. Intravenous injection of hyperpolarized 13C‐labeled bicarbonate results in the rapid production of hyperpolarized 13CO2 in the reaction catalyzed by carbonic anhydrase. As this reaction is close to equilibrium in the body and is pH dependent, the ratio of the 13C signal intensities from H13CO3– and 13CO2, measured using MRS, can be used to calculate pH in vivo. The application of this technique to a murine tumor model demonstrated that it measured predominantly extracellular pH and could be mapped in the animal using spectroscopic imaging techniques. A second approach has been to use the production of hyperpolarized 13CO2 from hyperpolarized [1‐13C]pyruvate to measure predominantly intracellular pH. In tissues with a high aerobic capacity, such as the heart, the hyperpolarized [1‐13C]pyruvate undergoes rapid oxidative decarboxylation, catalyzed by intramitochondrial pyruvate dehydrogenase. Provided that there is sufficient carbonic anhydrase present to catalyze the rapid equilibration of the hyperpolarized 13C label between CO2 and bicarbonate, the ratio of their resonance intensities may again be used to estimate pH, which, in this case, is predominantly intracellular. As both pyruvate and bicarbonate are endogenous molecules they have the potential to image tissue pH in the clinic. Copyright © 2011 John Wiley & Sons, Ltd.
Properties of linear poly(lactic acid)/polyethylene glycol blends
Authors: Sungsanit K. , Kao N. , Bhattacharya S.N.
Published: August 2011

Poly(lactic acid) (PLA) has great potentials to be processed into films for packaging applications. However, film production is difficult to carry out due to the brittleness and low melt strength of PLA. In this investigation, linear PLA (L‐PLA) was plasticized with poly(ethylene glycol) (PEG) having MW of 1000 g mol−1 in various PEG concentrations (0, 5, 10, 15, and 20 wt%). In relation to plasticizer content, the impact resistance and crystallinity of L‐PLA was increased, whereas a decrease in glass transition temperature and lower stiffness was observed. Nevertheless, the phase separation has been found in samples which contained PEG greater than 10 wt%. The dynamic and shear rheological studies showed that the plasticized PLA possessed lower viscosity and more pronounced elastic properties than that of pure PLA. Both storage and loss moduli decreased with PEG loading at all frequencies while storage modulus exhibited weak frequency dependence with increasing PEG content. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Morphology and mechanical properties of polypropylene/polystyrene blends compatibilized with styrene–butadiene block copolymers
Authors: Fortelný I. , Minkova L.I. , Kotek J. , Lapčíková M. , Michálková D.
Published: August 2011

The effect of molecular structure of styrene–butadiene block (SB) copolymers on the morphology, tensile properties, impact strength, and microhardness of polypropylene/polystyrene (PP/PS) (80/20) blends was studied. The addition of SB copolymers substantially reduces the size of dispersed PS particles formed at mixing. The distribution of SB copolymers between the interface and bulk phases is controlled by the length of styrene blocks in SB, but a decrease in the size of PS particles at mixing correlates with total molecular weight of SB copolymers. For a substantial part of compatibilized blends, PS particles aggregate rapidly during compression molding and form honeycomb‐like particles split by SB partitions, which persist at further annealing. Aggregation of PS particles continues slowly at further annealing. Blends containing PS particles with well‐developed honeycomb structure show lower yield stress, higher plasticity, and lower tensile impact strength than the blends having PS particles with simple or undeveloped honeycomb structure. Microhardness of PP/PS blends is additive and of PP/PS/SB blends is lower than the additive due to the effect of SB copolymers on crystalline structure of PP matrix. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Formulation of new synthetic binders: Thermomechanical properties of resin/recycled polymer blends
Authors: Fuentes‐Audén Cristina , Martínez‐Boza Francisco J. , Navarro Francisco J. , Partal Pedro , Gallegos Críspulo
Published: August 2011

Synthetic binders are special paving materials manufactured by mixing polymers, resins, and oils. These materials may have improved mechanical properties as compared with the traditional modified bitumen. This work is part of a comprehensive study on the design of synthetic binders with selected mechanical properties. In this sense, upgraded mechanical properties of the final synthetic binder can be attained by understanding and correlating the mechanical properties of its individual constituents as a function of composition and temperature. With this aim, this work deals with the thermomechanical properties of recycled polymer/resin blends, over a wide range of temperature and composition. Recycled polymer/resin blends are thermorheologically complex materials, due to the development of multiphase domains depending on polymer concentration. Thus, these blends show a predominantly gel‐like behavior at high polymer concentrations and a predominantly viscous behavior, with high thermal susceptibility, for low polymer concentrations. The dynamic viscosities of the blends, as a function of polymer concentration and temperature, can be predicted using a logarithmic mixing rule. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Preparation and properties of addition curable silicone resins with excellent dielectric properties and thermal resistance
Authors: Zhang Beijing , Zhuo Dongxian , Gu Aijuan , Liang Guozheng , Hu Jiang‐Tao , Yuan Li
Published: August 2011

A new addition curable silicone resin (ASiR) system with excellent dielectric and thermal properties was developed, which consists of only two components: poly(methylphenylvinylsiloxane) (PMPVSi) and an end‐capped hydrogen‐functionalized hyperbranched polysiloxane (EHFHPSi). PMPVSi is synthesized by a green and controllable process; EHFHPSi is first synthesized via A2 + B3 approach, and then end‐capped by hexamethyldisiloxane (HMDS). Three formulations were designed to investigate the optimum stoichiometry. Results show that cured ASiR resins have greatly different dielectric and thermal properties because of the different chemical structure of cured networks resulting from the different stoichiometries. The resin with a suitable stoichiometry has not only excellent dielectric properties including extremely low dielectric constant (2.96 at 1 Hz) and loss (0.0003 at 1 Hz) as well as good stability on frequency, but also outstanding thermal resistance, exhibiting great potential to be used as a new kind of high‐performance resins for many cutting‐edge industries, especially the microelectronic and insulation fields. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Synthesis, characterization, and thermal degradation of novel poly(2‐(5‐bromo benzofuran‐2‐yl)‐2‐oxoethyl methacrylate)
Authors: Koca Murat , Kurt Adnan , Kirilmis Cumhur , Aydogdu Yildirim
Published: August 2011

A novel methacrylate monomer containing benzofuran side group, 2‐(5‐bromo benzofuran‐2‐yl)‐2‐oxoethyl methacrylate (BOEMA), was synthesized from esterification reaction of 2‐bromo‐1‐(5‐bromo benzofuran‐2‐yl) ethanone with sodium methacrylate at 85°C in the presence of 1,4‐dioxane solvent. After characterization with Fourier transform infrared spectrophotometer, nuclear magnetic resonance (1H‐NMR and 13C‐NMR), its homopolymerization was carried out by free radical polymerization at 60°C in the presence of benzoyl peroxide initiator and 1,4‐dioxane solvent. The glass transition temperature (Tg) of the synthesized novel polymer, poly(2‐(5‐bromo benzofuran‐2‐yl)‐2‐oxoethyl methacrylate) [poly(BOEMA)], was determined to be 137°C with differential scanning calorimetry technique. Thermal degradation kinetics of poly(BOEMA) was investigated by thermogravimetric analysis method at different heating rates with 5°C/min intervals between measurements. From dynamic measurements, the analysis of each process mechanism of Coats–Redfern and Van Krevelen methods showed that the most probable model for the decomposition process of poly(BOEMA) homopolymer agrees with the random nucleation, F1 mechanism. The apparent decomposition activation energies of poly(BOEMA) by Kissinger's and Flynn–Wall–Ozawa methods in the studied conversion range were 188.47 and 180.13 kJ/mol, respectively. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Exhaustive glycosylation, pegylation, and glutathionylation of a [G4]‐ene48 dendrimer via photoinduced thiol‐ene coupling
Authors: Conte Mauro Lo , Robb Maxwell J. , Hed Yvonne , Marra Alberto , Malkoch Michael , Hawker Craig J. , Dondoni Alessandro
Published: August 2011

The use of free‐radical thiol‐ene coupling (TEC) for the introduction of carbohydrate, poly(ethylene glycol), and peptide fragments at the periphery of an alkene functional dendrimer has been reported in this article. Four different sugar thiols including glucose, mannose, lactose, and sialic acid, two PEGylated thiols, and the natural tripeptide glutathione were reacted with a fourth generation alkene functional dendrimer [G4]‐ene48 on irradiation at λmax 365 nm. In all cases, the 1H NMR spectra of the crude reaction mixture revealed the complete disappearance of alkene proton signals indicating the quantitative conversion of all 48 alkene groups of the dendrimer. With one exception only, all dendrimer conjugates were isolated in high yields (70–94%), validating the high efficiency of multiple TEC reactions on a single substrate. All isolated and purified compounds were analyzed by matrix assisted laser desorption ionization‐time of flight (MALDI‐TOF) spectrometry and gave spectra consistent with the assigned structure. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Differences in water sorption and proton conductivity between Nafion and SPEEK
Authors: Wu Xuemei , Wang Xiaowen , He Gaohong , Benziger Jay
Published: August 2011

Water sorption, volumetric expansion, and proton conductivity of 1100 EW Nafion and 555 EW sulfonated polyetheretherketone (SPEEK) were compared as functions of water activity at 60 and 80 °C. Water sorption in Nafion occurs with a small positive volume of mixing, ∼0.005 cm3/cm3. In contrast, water sorption in SPEEK has a large negative volume of mixing ∼−0.05 cm3/cm3. The percolation thresholds for proton conduction occur at hydrophilic volume fractions of 0.10 in Nafion and 0.30 in SPEEK. Proton conductivity increases quadratically with hydrophilic volume fraction above the percolation threshold. The different percolation thresholds suggest the hydrophilic domains in Nafion grow from lamella, whereas the hydrophilic domains in SPEEK grow from spheres. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 49: 1437–1445, 2011
Editorial Introduction: Re‐Making Migration Theory
Authors: Smith Darren P. , King Russell
Published: August 2011

In this editorial introduction to the special issue, we first make a series of key points about the importance of migration in today's globalised world and about the intersectionality of migration processes, which should never be studied in isolation from the various social, economic, and political phenomena within which they are embedded. The paper also draws attention to the increasing diversity of migration, which poses a challenge to ongoing attempts at new theorisation. Within geography, we note that the traditional concerns of population geographers to map and model migration have been broadened by ‘turns’ towards cultural and post‐modern frameworks for understanding the nature of migration. In the final part of the paper, we summarise the six papers that follow, highlighting the unique contribution that each makes to our overall agenda of ‘remaking migration theory’ from a geographic perspective. Copyright © 2011 John Wiley & Sons, Ltd.
Determination of MBE grown wurtzite GaN/Ge3N4/Ge heterojunctions band offset by X‐ray photoelectron spectroscopy
Authors: Kumar Mahesh , Rajpalke Mohana K. , Roul Basanta , Bhat Thirumaleshwara N. , Kalghatgi A. T. , Krupanidhi S. B.
Published: August 2011

Hexagonal Ge3N4 layer was prepared on Ge surface by in situ direct atomic source nitridation and it is promising buffer layer to grow GaN on Ge (111). The valence band offset (VBO) of GaN/Ge3N4/Ge heterojunctions is determined by X‐ray photoemission spectroscopy. The valence band (VB) of Ge3N4 is found to be 0.38 ± 0.04 eV above the GaN valance band and 1.14 ± 0.04 eV below the Ge. The GaN/Ge3N4 and Ge3N4/Ge are found type‐II and type‐I heterojunctions, respectively. The exact measurements of the VBO and conduction band offset (CBO) are important for use of GaN/Ge3N4/Ge (111) heterosystems.
Kinetics and isotherm studies on electrosorption of NaCl by activated carbon fiber, carbon nanotube and carbon nanotube‐carbon nanofiber composite film
Authors: Zhan Yankun , Nie Chunyang , Li Haibo , Pan Likun , Sun Zhuo
Published: August 2011

This paper presents a comparative study on electrosorptive behavior of activated carbon fiber (ACF), carbon nanotube (CNT) and carbon nanotube‐carbon nanofiber (CNT‐CNF) composite in NaCl solution. The result shows that CNT‐CNF exhibits a higher NaCl removal ratio with a faster electrosorption rate than ACF and CNT due to its more hydrophilic surface, higher specific capacitance and more suitable mesoporous structure (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Property study of aluminium oxide thin films by thermal annealing
Authors: Zhao Zhiwei , Tay Beng Kang
Published: August 2011

Aluminium oxide thin films had been prepared by off‐plane filtered cathodic vacuum arc (FCVA) under the oxygen partial pressure of 5 × 10‐4 Torr at room temperature. Annealing effects on the properties of the films between 200 °C and 900 °C were investigated. Experiments results showed that the surfaces of aluminium oxide thin films remained smooth up to 600 °C. Crystallization is induced for the film annealed at 900 °C. It was also found that refractive index of the films increased with increasing the annealing temperature. Strong frequency dispersion of refractive index was found and fitted to a single oscillator model. The dispersion parameters, such as single oscillator energy, dispersion energy, average oscillator strength and its related wavelength, were estimated. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effects of ultraviolet irradiation and soak time on the leakage current of Bi3.25La0.75Ti3O12 thin films
Authors: Wu Xiumei , Zhai Ya , Xu Mingxiang , Kan Yi
Published: August 2011

Bi3.25La0.75Ti3O12 thin films with the thickness of about 365 nm were prepared on Pt/Ti/SiO2/Si substrates using the conventional metal organic decomposition method. The leakage current behaviour influenced by the soak time and the ultraviolet irradiation were studied. It was found that, on the one hand, when the testing voltage is below 2 V, the soak time has no significant effect on the leakage current. When the testing voltage increases to 5 V, the leakage current increases with the soak time increasing. On the other hand, the ultraviolet irradiation can change the leakage current of the thin films. When the testing voltage is above 4 V, with the illumination time increasing, the leakage current increases. The charge carriers participating in electric conduction were used to explain these experimental results (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Heat‐induced magnetic properties changes of Mn3[Fe(CN)6]2·xH2O
Authors: Liu Min , Xu Mingxiang
Published: August 2011

Polycrystalline sample of Mn3[Fe(CN)6]2·xH2O was prepared by coprecipitation method. The coprecipitated powder was annealed in vacuum at different temperatures of 80, 100, 130, and 150 °C respectively. Changes of magnetic properties with different annealed temperatures were studied by Fourier‐transform infrared, X‐ray diffraction and magnetization measurements. The positive θ value of the Curie–Weiss temperature indicates the existence of a predominant ferromagnetic interaction over the anti‐ferromagnetic one in the compounds annealed at 80, 100, and 150 °C. The negative value of θ in Mn3[Fe(CN)6]2·xH2O annealed at 130 °C appears to be the coexistence of a strong anti‐ferromagnetic and a ferromagnetic interactions in the material. This is due to the existence of a relatively strong anti‐ferromagnetic contribution between the neighbouring Mn atoms bridged by the oxygen atom of the water molecule (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Haemodynamics and cardiac function during robotic‐assisted laparoscopic prostatectomy in steep Trendelenburg position
Authors: Haas Sebastian , Haese Alexander , Goetz Alwin E. , Kubitz Jens C.
Published: August 2011

Background

Robotic‐assisted laparoscopic prostatectomy (RALP) is usually performed in steep Trendelenburg position, which can be associated with cardiac impairment due to positioning and capnoperitoneum. This study investigated haemodynamic consequences and cardiac function in this type of surgery and evaluated the hypothesis that steep Trendelenburg position and capnoperitoneum results in haemodynamic and ventricular impairment.

Methods

10 patients (ASA I‐III) scheduled for RALP in steep Trendelenburg position with capnoperitoneum were prospectively studied. Heart rate (HR), mean arterial pressure (MAP) and central venous pressure (CVP) were recorded. Stroke volume variation (SVV) and cardiac output (CO) were measured using pulse‐contour analysis. Further, cardiac function was assessed using trans‐oesophageal echocardiography before positioning (T1) and 10 min (T2) and 60 min (T3) after implementation of steep Trendelenburg position and capnoperitoneum.

Results

HR did not change statistically. MAP (T1, 69.7 ± 1.55; T2, 82.9 ± 3.05; T3, 79.4 ± 2.18 mmHg), CVP (T1, 7.7 ± 1.3; T2, 17.3 ± 2.01; T3, 16.9 ± 1.66 mmHg) and CO (T1, 4.0 ± 0.15; T2, 4.9 ± 0.26; T3, 4.9 ± 0.36 l/min) increased significantly at T2 and T3. Echocardiography showed no deterioration of left or right ventricular function. In one patient with pre‐existing mitral valve insufficiency (I°) an aggravation of the insufficiency (III°) was observed. No other valve dysfunctions were observed.

Conclusions

The steep Trendelenburg position may improve haemodynamic function and does not deteriorate left or right ventricular function during RALP. However, mitral valve insufficiency may be aggravated by positioning and capnoperitoneum. Copyright © 2011 John Wiley & Sons, Ltd.
A miniature patient‐mount navigation system for assisting needle placement in CT‐guided intervention
Authors: Lin Mu‐Lien , Yang Been‐Der , Wang Yao‐Hung , Yang Chi‐Lin , Wang Jaw‐Lin
Published: August 2011

Background

CT‐guided intervention is routinely performed in an iterative fashion that often leads to lengthy operation and high X‐ray exposure to patients. To streamline the workflow, we develop a patient‐mount navigation system for assisting needle placement in CT‐guided interventions.

Methods

The system comprises three components, a miniature patient‐mount tracking unit, an auto‐registered reference‐frame unit and an intuitive image‐processing unit. The system is operated like a virtual biplane fluoroscopy with augmented CT reconstructed images to streamline the conventional CT‐guided intervention workflow. Surgery efficiency and safety can be increased, while radiation for patients and surgeons can be reduced. Two preclinical validations were conducted to evaluate the technical applicability and accuracy of the system.

Results

The results of the rigid physical phantom test showed a machine position error of 1.6 mm and a tilting error of 1.5°. The results of the deformable porcine phantom test showed the operation position error to be 3.6 mm and tilting error to be 2.9°.

Conclusions

We concluded that the accuracy of our system is within the comparable range of the existing navigation systems. Copyright © 2011 John Wiley & Sons, Ltd.
The render button: How a high‐end graphics company developed a personal graphics product
Authors: Pittman Jon H.
Published: August 2011

The Personal Visualizer™ was developed to enable a casual user to create high‐quality rendered images. Providing sophisticated rendering techniques to casual users forced us to confront a number of issues and to undergo a shift in values. These issues are outlined, and the ways we dealt with them are discussed. Things we would do differently as a result of our development experiences are also discussed.
Multidimensional illumination functions for visualization of complex 3D environments
Authors: Mudur S. P. , Pattanaik S. N.
Published: August 2011

This paper presents a new view‐independent, energy equilibrium method for determining the light distributed in a complex 3D environment consisting of surfaces with general reflectance properties. The method does not depend on discretization of directions or discretization of surfaces to differential elements. Hence, it is a significant improvement over the earlier complete view‐independent method which is computationally intractable for complex environments or the hybrid methods which include an extended view‐dependent ray tracing second pass. The new method is based on an efficient data structure of order O(N2) called the spherical cover. The spherical cover elegantly captures the complex multidimensional directional nature of light distributed over surfaces. Subdivision techniques based on range estimation of various parameters using interval‐arithmetic‐like methods are next described for efficiently computing the spherical cover for a given 3D environment. Using the spherical cover, light is progressively propagated through the environment until energy equilibrium is reached. Complexity analysis of the propagation step is carried out to show that the method is computationally tractable. The paper also includes a comprehensive review of earlier rendering techniques viewed from the point of view of capturing the multidimensional nature of light distribution over surfaces.
An annotated bibliography of scientific visualization. Part 1
Authors: Nielson Gregory M. , Voegele Keith
Published: August 2011

This bibliography evolved as a network using the papers in the volume Visualization of Scientific Computing edited by Gregory M. Nielson and Bruce Shriver and published by IEEE Computer Society Press, 1990 as the root nodes. From there, the supplied reference lists were recursively traversed until a closure resulted either from the common links or from the effective grounding by the highly technical literature of application specializations.

As usual, the standard disclaimers apply; so, for example, this collection is hopefully complete (in the sense that subsets of papers form research vectors that span the space of scientific visualization), but obviously not exhaustively comprehensive. Some of the entries are of a general survey nature, whereas others are quite specific and technical. Pivotal and often quoted works comprise the bulk of the material, but works of historical and developmental significance are also included especially where they point to researchers, research centres and journals where important work has been, and is being, performed and recorded. The annotations accompanying the references tend to be impressionistic and apologies to the authors are hereby noted for those instances where omissions, misunderstandings and whimsy have resulted in misinterpretations.
Digestive plasticity as a response to woodland fragmentation in roe deer
Authors: Serrano Ferron Emmanuel , Verheyden Hélène , Hummel Jürgen , Cargnelutti Bruno , Lourtet Bruno , Merlet Joel , González‐Candela Mónica , Angibault Jean Marc , Hewison Aidan Jonathan Mark , Clauss Marcus
Published: August 2011

Digestive plasticity, which refers to changes in digestive features due to changes in both internal and external environmental conditions, is a crucial factor for understanding the ability of species to cope with environmental changes. In Europe, agricultural intensification and the loss of forests have been major challenges for original forest dwellers, however some species, such as the European roe deer (Capreolus capreolus), have been able to successfully colonize these new habitats. In this work, we investigated the adaptation of some digestive features of roe deer to the agricultural landscapes. We assessed whether changes in local landscape structure influenced the mass of both reticulorumen (RR) and distal fermentation chamber (DFC) of 47 juvenile and adult roe deer inhabiting an agro‐ecosystem in southwest France. Woodland cover had a clear effect on diet quality (estimated by the rate of gas production of digestive contents) and DFC weight of animals. In fact, deer from the most forested landscapes showed heavier DFCs and fed on poorer quality diet (lower gas production) than their counterparts from the most open landscapes. RR mass was less influenced by the landscape openness, being the age of animals the main factor for understanding the variations of this digestive feature in our study area. We can conclude that colonizing agricultural landscapes increases the access to highly energetic and digestive resources.
Distribution patterns of oil and gas accumulations in West Siberia
Authors: Brekhuntsov A.M. , Monastyrev B.V. , Nesterov I.I.
Published: August 2011

The current geological and geophysical exploration maturity and the structure of resource base have been presented for the West Siberian Basin. The patterns of oil and gas content distribution, both in areal extent and vertical, have been considered throughout the entire cover and its constituent oil-gas plays. Structural constructions for four major stratigraphic levels have been analyzed: the bottom of the Mesozoic–Cenozoic cover, the Jurassic and Lower Aptian top, and the bottom of Turonian deposits. The distribution patterns of oil and gas accumulations in each oil-gas play are controlled by a specific combination of parameters such as the distribution of reservoirs and seals, the presence of oil-and-gas source rocks, the level of organic matter maturity, facies and tectonic conditions, thermobaric and hydrogeochemical subsoil environments, etc.
The tectonic framework and hydrocarbon prospectivity of the western Yenisei–Khatanga regional trough
Authors: Kontorovich V.A.
Published: August 2011

The western part of the Yenisei–Khatanga trough is one of the least explored regions, which are thought to possess an excellent hydrocarbon resource potential. This region is geographically located in the southern part of the Taimyr Peninsula, within the Krasnoyarsk Territory.

Utilizing regional seismic data, structure and thickness maps for seismic sequences allowed the reconstruction of the structural framework and tectonic evolution of the region. The study reveals a number of tectonic processes in the region that took place in the Paleozoic, Mesozoic, and Cenozoic and establishes the main evolutionary stages of a series of large structures of different ranks.

The study also provides some insights into the structural features and depositional environments of Paleozoic, Triassic–Jurassic, Neocomian, Aptian–Albian–Cenomanian, and Turonian–Cenozoic sedimentary sequences. Based on the relationship between tectonic activity and hydrocarbon generation, the conclusion was made about a high hydrocarbon resource potential of the Neocomian clinoform sequence in the Yenisei–Khatanga regional trough.
Petrology, sedimentology, geochemistry, and absolute age of Triassic volcanosedimentary rocks from the southwest of the West Siberian geosyneclise (Kurgan Region)
Authors: Saraev S.V. , Baturina T.P. , Travin A.V.
Published: August 2011

In this study we report new Ar-Ar ages for basalt (261.0 ± 15, 249.4 ± 3.0, 247.0 ± 3.1 Ma) and rhyolite (246.9 ± 2.6 Ma) samples collected from the Triassic volcanosedimentary sequence, which is one of the remarkably complete and structurally complex sections in the southwest of the West Siberian geosyneclise (WSG) (East Kurganskaya-42 (EK-42) and East Kurganskaya-43 (EK-43) wells), largely comprising basalts and conformable layers of rhyolites, acid tuffs, limestones, and silty mudstones. It was shown that basalts, which constitute most of the section, are geochemically similar to medium-K tholeiitic and calc-alkaline basalts in the southern extension of the Koltogory–Urengoi rift (Nikol’skaya-1 well). Rhyodacites and rhyolites from the section of interest belong to the potassic to potassic-sodic series of normal alkalinity. The trace element compositions of the rhyolites and host basalts suggest fractionation from primary magmas during formation of felsic rocks. No low-K sheet-flow basalts have been encountered in the sections penetrated by the three wells (EK-42, EK-43, and Nikol’skaya-1), as opposed to sections in the northern part of the Koltogory–Urengoi rift (TSD-6 well) and the Siberian flood basalt province.

Despite their small thickness, the sedimentary units provide evidence for different depositional settings during the evolution of a volcanosedimentary basin. Similar to the Koltogory–Urengoi rift, deposition of the Presnogor’kovsk graben fill indicates intermittent marine conditions with accumulation of hyaloclastites, and fine, calcareous, silt- and clay-rich carbonaceous oozes associated with a background sedimentation, which contain abundant marine fauna, pyrite and rare distal turbidites with glauconites. The geochemical features of these sedimentary rocks were largely defined by a bimodal syndepositional volcanism. During the Early Triassic, a system of rifts and grabens that was developed within the continental plateau over much of the WSG allowed the intermittent ingress of sea-water from the north (in present coordinates) far southwards and southwestwards up to the latitude of Omsk and Kurgan. As a result of extensive erosion of the continental plateau, the packages of low-K sheet-flow basalts were removed from the upper part of the sections of deep wells, which became dominated by the eroded roots of the West Siberian traps (subalkaline and alkaline rift basalts).
Petroleum systems of the Timan–Pechora sedimentary basin (including the offshore Pechora Sea)
Authors: Prischepa O.M. , Bazhenova T.K. , Bogatskii V.I.
Published: August 2011

The sedimentary cover of the Timan–Pechora petroleum basin records several phases of tectonic activity in the area: rifting and incipient ocean opening; a passive margin setting with intracontinental rifts and aulacogen, an intrashelf depression and inversion swells; collisional orogeny with the development of a foredeep; vertical isostatic movements associated with the development of a late syneclise and renewed orogenic movements. The deposition of source and reservoir facies occurred during the divergent phases of the tectogenesis (Ordovician–Tournaisain). The formations that accumulated during a convergent tectonic regime (Visean–Triassic) comprise mostly reservoir rocks. Because of thermal maturity of organic matter, the sedimentary rocks in the area span the broad range of oil and gas generation zones. The identified hydrocarbon kitchen areas were developed in different geodynamic settings: in the east of a passive margin, within rift-related troughs, and in the Ural foredeep. The first two were more liquids-prone fairways, with predominant oil and condensate generation, whereas the latter was largely a gas- and gas-condensate-generative source. The change of structural settings, the extension of oil and gas kitchens, variation of the regional dip, and recurrent faulting caused both the formation of new play fairways and the destruction of existing ones. The new oil-prone fairways that formed synchronously with the onset of intense oil generation might have later evolved into oil- and gas-prone fairways or even oil-, gas-, condensate-prone fairways at the expense of the gas component of petroleum systems, which is thought to increase as a source rock generating mostly oil became capable of generating oil, gas, and condensate. In addition, tectonically active zones may provide the most favorable conditions for the formation of gas and gas-condensate accumulations due to a decrease in formation pressure and expulsion of a free gas phase or due to its updip migration from great depths. Analysis of hydrocarbon generation and accumulation conditions provided insights into the evolution of a petroleum system of each play and transformation of a sedimentary basin into a petroleum basin. The study revealed the areal distribution patterns for oil and gas plays. The long-lived oil-prone plays are confined to a series of paleouplifts within the Izhma–Pechora and Khoreiver tectonically stable blocks. Oil-, gas-, and condensate-prone plays are associated with a tectonically active setting (Pechora–Kolva aulacogen and Timan block), whereas mostly gas- and condensate-prone plays are found within the Ural foredeep.
The Decider's Dilemma: Leader Culpability, War Outcomes, and Domestic Punishment
Authors: CROCO SARAH E.
Published: August 2011

A leader's culpability for involving his state in a conflict affects both his war termination calculus and his domestic audience's willingness to punish him if he loses. I define a culpable leader as any leader who either presides over the beginning of a war, or comes to power midwar and shares a political connection with a culpable predecessor. Using a data set created specifically for this study, I find that culpable leaders are more likely than nonculpable ones to achieve favorable war outcomes. I also find that domestic audiences will be willing to punish culpable leaders who lose, yet spare nonculpable leaders who do the same. Taken together, my findings underscore the need to appreciate more fully the role individual leaders play in bringing their states to war.
Effect of vitamins C and E supplementation onHelicobacter pylorieradication: a meta-analysis
Authors: Li Guogang , Li Lan , Yu Chaohui , Chen Li
Published: August 2011

Vitamins C and E can act as potent antioxidants to reduce the damage caused by reactive oxygen species in gastric mucosa. Whether vitamin supplements forHelicobacter pylorieradication regimen could improve the rate of eradication remains uncertain. Therefore, we performed a meta-analysis to evaluate the efficacy of vitamins C and E supplementation for the eradication ofH. pylori. Searches were conducted in the databases PubMed, EMBASE and Cochrane Library. Randomised controlled trials (RCT) that fulfilled the inclusion criteria and addressed the clinical questions of this analysis were further assessed. Of the six RCT included, five had a low methodological quality. Of the six RCT, three compared the efficacy of the eradication regimenv.eradication regimen plus vitamins C and E. The result of the meta-analysis showed a non-significant difference in the eradication rate ofH. pyloribetween the two groups (risk ratio (RR) 0·93,P = 0·76). Another three RCT compared the eradication regimenv.eradication regimen plus vitamin C only, and there too there was no significant difference in the eradication rate (RR 0·83,P = 0·32). In conclusion, vitamins C and/or E supplements to theH. pylorieradication regimen could not improve the eradication rate. However, currently available data do not draw a definitive conclusion about the effectiveness of antioxidant vitamins onH. pylorieradication, owing to the small sample size and low-to-moderate methodological quality.
Schistosoma haematobium infections in preschool children from two rural communities in Ijebu East, south-western Nigeria
Authors: Ekpo U.F. , Alabi O.M. , Oluwole A.S. , Sam-Wobo S.O.
Published: August 2011

There is an urgent need for information on schistosomiasis in preschool children, who are often excluded in mass treatment programmes. The prevalence and intensity of Schistosoma haematobium infection were determined in preschool children aged ≤ 6 years in two rural communities in Ijebu East, south-western Nigeria. Two urine samples each were collected from 83 preschool children from the two communities, tested for microhaematuria using reagent strips and then processed and examined with a microscope for S. haematobium eggs. Focus group discussions on perceptions of the disease and water contact practices were held in the communities with their guardians, caregivers and preschool children, using an interview guide. The prevalence of S. haematobium in the two communities was 14 (16.9%), with no significant differences (P = 0.661) in infection rate between boys (18.4%) and girls (14.7%). Both prevalence and intensity of infection did not increase significantly with age in both Korede and Obada community. However, there were significant differences in prevalence of infection between the two communities (P = 0.035). There was no association (P = 0.750) between intensity in boys (0.176 eggs/10 ml urine) and girls (0.110 eggs/10 ml urine). Focal group discussions with guardians and caregivers revealed that preschool children acquired infection early in their lives through exposure to infected stream water by their mothers, while the older children visit the stream for playing, bathing and swimming. It has therefore become imperative for preschool children to be included in the planning of schistosomiasis intervention programmes as a means of reducing transmission.
Transcatheter arterial embolisation for paediatric inflammatory pseudotumour of the maxillary sinus
Authors: Murai A , Sugiu K , Kariya S , Nishizaki K
Published: August 2011

Background:

Inflammatory pseudotumours are mostly seen in the lung, and occasionally in the head and neck region including the sinonasal area. Reported treatment modalities comprise corticosteroid treatment, surgical excision and radiotherapy. The latter option is required because wide surgical resection may be difficult for head and neck lesions, especially in children. However, clinicians should be aware of the risk of late-onset side effects of radiotherapy in children.

Case report:

We present a two-year-old girl with a massive inflammatory pseudotumour of the maxillary sinus. Transcatheter arterial embolisation was performed, and the lesion was successfully managed without additional therapy. There was no evidence of recurrence over the next five years.

Conclusion:

This is the first report presenting the utility of arterial embolisation for inflammatory pseudotumour.
Present status of the commercial sea cucumber fishery off the north-west and east coasts of Sri Lanka
Authors: Dissanayake D.C.T. , Stefansson G.
Published: August 2011

The sea cucumber fishery has been providing an important means of livelihood to the coastal fishing communities in Sri Lanka for centuries. Stock status, level of exploitation and mortality parameters of eleven commercial sea cucumber species were studied off the north-west and the east coasts of Sri Lanka using data collected from an underwater visual census and fishery-dependent surveys carried out in 2008 and 2009. The total abundance of sea cucumbers was higher in the north-west than the east (P < 0.01). However, the total abundance of all the species declined between 2008 and 2009. The commercial fishery predominantly relies on two nocturnal species:Holothuria spiniferaandThelenota anax. Holothuria spiniferahad the highest contribution (73.2%) to the total landings in the north-west while this was provided byT. anax(93%) in the east. Both catch per unit effort and total landings declined in 2009 compared to 2008 having three exceptions (H. spinifera, Holothuria atraandStichopus chloronotus) in the north-west. Further, the collection of immature individuals, reduced landings of high-value species and temporal shifting of fishing activities were observed in both areas. Two approaches (simple linear regression and random effects models) were used to estimate the natural mortality of sea cucumbers and the estimated values were 0.50 yr−1and 0.45 yr−1, respectively. Apart from the management of local sea cucumber resources, this information is important to update the regional and global sea cucumber statistics as well as for launching regional management programmes.
Paeoniflorin attenuates schistosomiasis japonica-associated liver fibrosis through inhibiting alternative activation of macrophages
Authors: CHU DEYONG , DU MINGZHAN , HU XIANGYANG , WU QIANG , SHEN JILONG
Published: August 2011

Interleukin (IL)-13 and alternatively activated macrophages (AAMs) play an important role in liver granuloma and fibrosis of schistosomiasis. Paeoniflorin (PAE, C23H28O11) has been reported to have an anti-hepatic fibrosis effect in schistosomiasis; however, the mechanism has not been fully elucidated. In this study, we measured serum hyaluronic acid (HA) concentrations, liver granuloma diameter and volume density, fibrosis degree and expressions of IL-13, arginase-1 (ARG-1), nitric oxide synthase-2 (NOS-2), and phosphorylated signal transducer and activator of transcription 6 (p-STAT6) in mice liver of schistosomiasis. Then we detected expressions of specific biomarkers of AAMs and activity of Arg-1 in Kupffer cells (KCs) from infected and PAE-treated mice, or in KCs from uninfected mice, but exposed to rIL-13in vitro. Finally, we observed expression of IL-13 signalling molecules in KCs and secretion of IL-13 from lymphocytes of infected and PAE-treated mice. Our results showed that during schistosomiasis, IL-13 expression and secretion increased with liver macrophages activated alternatively. PAE not only directly inhibited alternative activation of macrophages via reducing the phosphorylations of janus-activated kinase 2 (JAK2) and/or STAT6, leading to reduction of AAMs-related markers and Arg-1 activity, but also indirectly suppressed alternative activation of macrophages through decreasing secretion of IL-13. PAE might be a promising prophylactic agent for hepatic granuloma and fibrosis of schistosomiasis japonica.
Third lineage of rodent eimerians: morphology, phylogeny and re-description of Eimeria myoxi (Apicomplexa: Eimeriidae) from Eliomys quercinus (Rodentia: Gliridae)
Authors: KVIČEROVÁ JANA , MIKEŠ VÁCLAV , HYPŠA VÁCLAV
Published: August 2011

Coccidian oocysts from feces of 46 individuals of the garden dormouse, Eliomys quercinus (Rodentia: Gliridae), were morphologically and molecularly characterized. Both morphological and sequence data (18S rDNA and ORF 470) showed low variability, indicating that all samples represent a single species. By comparison with published morphological descriptions of coccidia from glirid rodents, we determined that the samples represent Eimeria myoxi. Molecular data suggest that this species does not fall within the 2 known rodent-specific groups but branches as a third independent lineage. However, its exact position in respect to other eimerian clusters could not be established due to the lack of phylogenetic information at this taxonomic level for the 18S rRNA and ORF 470 genes. Based on these results, we provide a re-description of Eimeria myoxi, which contains morphological and molecular characteristics sufficient for its further unequivocal identification.
Leishmanicidal effect ofSpiranthera odoratíssima(Rutaceae) and its isolated alkaloid skimmianine occurs by a nitric oxide dependent mechanism
Authors: DOS SANTOS ROGERIO ALEXANDRE NUNES , BATISTA JOÃO , ROSA SUELLEN IARA GUIRRA , TORQUATO HERON FERNANDES , BASSI CARMEN LÚCIA , RIBEIRO TEREZA AUXILIADORA NASCIMENTO , DE SOUSA PAULO TEIXEIRA , BESSERA ÂNGELA MÁRCIA SELHORST E SILVA , FONTES COR JESUS FERNANDES , DA SILVA LUIZ EVERSON , PIUVEZAM MÁRCIA REGINA
Published: August 2011

Leishmaniasis is one of the neglected diseases. High cost, systemic toxicity, and diminished efficacy due to development of resistance by the parasites has a negative impact on the current treatment options. Thus, the search for a new, effective and safer anti-leishmanial drug becomes of paramount importance. Compounds derived from natural products may be a better and cheaper source in this regard. This study evaluated thein vitroanti-leishmanial activity ofSpiranthera odoratíssima(Rutaceae) fractions and isolated compounds, using promastigote and amastigote forms of differentLeishmaniaspecies. J774 A.1 macrophage was used as the parasite host cell for thein vitroassays. Evaluations of cytoxicity, nitric oxide (NO), interleukin-10 andin silicoanalysis were carried out.In vitroexperiments showed that the fruit hexanic fraction (Fhf) and its alkaloid skimmianine (Skm) have a significant (P<0·001) effect againstL. braziliensis. This anti-L. braziliensisactivity of Fhf and Skm was due to increased production of NO and attenuation of IL-10 production in the macrophages at concentrations ranging from 1·6 to 40·0μg/ml. Thein silicoassay demonstrated significant interaction between Skm and amino acid residues of NOS2. Skm is thus a promising drug candidate forL. braziliensisdue to its potent immunomodulatory activity.