bluuebunny/crossref_metadata_2025_split huggingface dataset:
Control over Party and Campaign Finance in Mexico
Authors: Peschard Jacqueline 
Published: May 2006

This article offers a detailed description of how electoral laws have developed a legal framework to make Mexican political parties accountable, and how electoral authorities, both administrative (the Instituto Federal Electoral–IFE) and judicial (the Tribunal Electoral del Poder Judicial de la Federación–TEPJF), have contributed to enhancement of public control over party resources through a series of regulatory mandates and judicial resolutions they have issued. The two famous cases of illegal campaign financing in 2000 showed that the legal instruments at IFE's disposal are still insufficient to keep track of irregularities and to avoid illegal funding. A second generation of electoral reforms is necessary to overcome such legal obstacles.
El artículo presenta una descripción detallada de cómo ha evolucionado la legislación electoral en México para lograr una adecuada rendición de cuentas de los partidos políticos, así como una relación de los acuerdos y resoluciones que ha dictado la autoridad electoral tanto administrativa (el Instituto Federal Electoral–IFE), como jurisdiccional (el Tribunal Electoral del Poder Judicial de la Federación–TEPJF) para reforzar el control sobre las finanzas de los partidos políticos. Los dos casos de financiamiento ilegal de la campaña del 2000 mostraron las limitaciones de los instrumentos legales para evitar el financiamiento ilícito. Una reforma electoral de segunda generación es necesaria para superar dichos obstáculos.
Immunohistochemical investigation of angiogenic factors in parathyroid proliferative lesions
Authors: Lazaris Andreas C , Tseleni-Balafouta Sofia , Papathomas Thomas , Brousalis Theodore , Thomopoulou Georgia , Agrogiannis George , Patsouris Efstratios S 
Published: May 2006

Objective: The pathological distinction between parathyroid neoplasms and hyperplasias remains difficult in several cases. Endoglin (CD105) is a proliferation-associated and hypoxia-inducible protein abundantly expressed in angiogenic endothelial cells. Vascular endothelial growth factor (VEGF) induces angiogenesis and VEGF-R2 is a tyrosine kinase receptor expressed early in development by endothelial cell precursors. We attempted to examine whether immunohistochemical expression of CD105, VEGF and VEGF-R2 may be useful in distinguishing between parathyroid hyperplasia and neoplasia as well as to elucidate, to some extent, the mechanism of neovascularization in proliferative lesions of the parathyroid gland.
Design: Tissue specimens were taken from 38 patients with primary hyperparathyroidism (HPT) (17 adenomas and 21 primary hyperplasias) and from 30 patients with secondary HPT. Normal glands served as controls.
Methods: In a standard immunohistochemical procedure, monoclonal antibodies to endoglin, VEGF and VEGF-R2 were applied to detect angiogenic endothelial cells. Immunostaining was estimated by image analysis and statistical analysis was subsequently performed.
Results: Positive CD105 immunoreaction was significantly increased in parathyroid adenomas by comparison with primary hyperplasias (P = 0.033) and with secondary hyperplasias (P = 0.033). When parathyroid adenomas, primary hyperplasia and secondary hyperplasia specimens were comparatively evaluated, VEGF immunoreaction was much more common in adenomas (P = 0.018). In addition, in samples with secondary hyperplasia, VEGF-R2 immunoreactivity was positively linked with VEGF expression as well as with the apoptotic index of parathyroid cells (P = 0.038 and 0.010 respectively). In secondary hyperplasia specimens, an inverse correlation between cyclin D1 immunoexpression and angiogenic indexes, such as CD105 and VEGF, was noticed (P = 0.007 and 0.0017 respectively).
Conclusions: This study shows increased angiogenesis in parathyroid adenomas compared with parathyroid proliferative lesions. In secondarily hyperplastic glands increased angiogenesis and increased apoptosis occur simultaneously; in the latter glands, the overexpression of cyclin D1 does not appear to be the genetic abnormality responsible for increased angiogenesis.
Effect of Ultraviolet‐B Radiation on Salt Marsh Vegetation: Trends of the Genus Salicornia along the Americas
Authors: Costa C. S. B. , Armstrong R. , Detrés Y. , Koch E. W. , Bertiller M. , Beeskow A. , Neves L. S. , Tourn G. M. , Bianciotto O. A. , Pinedo L. B. , Blessio A. Y. , Roman N. San 
Published: May 2006

ABSTRACTThe effects of natural UV‐B radiation on growth, photo‐synthetic and photoprotective pigment composition of different Salicornia species were analyzed in salt marshes at three different sites along the Americas (Puerto Rico, southern Brazil and Patagonia, Argentina). Plants were exposed to different levels of UV‐B radiation for 1–2 years in situ as well as in outdoor garden UV‐B exclusion experiments. Different UV‐B levels were obtained by covering plants with UV‐B opaque (blocked 93–100% of ambient UV‐B) and UV‐B attenuating (near‐ambient) filters (reduced 20–25% of UV‐B). Unfiltered plants were exposed to natural irradiance. UV‐B filters had significant effects on temperature and photosynthetic pigments (due to changes in PAR; 400–700 nm). The growth of Salicornia species was inhibited after 35 to 88 days of exposure to mean UV‐B radiation dosages between 3.6 and 4.1 kJ m−2 day−1. The highest number of branches on the main shoot (S. bigelovii and S. gaudichaudiana) and longest total length of the branches (S. gaudichaudiana) were observed in the UV‐B opaque treatment. Salicornia species responded to increasing levels of UV‐B radiation by increasing the amount of UV‐B absorbing pigments up to 330%. Chromatographic analyses of seedlings and adult S. bigelovii plants found seven different UV‐B absorbing flavonoids that are likely to serve as UV‐B filtering pigments. No evidence of differential sensitivity or resilience to UV‐B radiation was found between Salicornia species from low‐mid latitudes and a previously published study of a high‐latitude population.
Three soil improvement methods and their applications to road construction
Authors: Chu J. , Yan S. W. , Zheng Y. R. 
Published: May 2006

To cater for the massive development in transportation infrastructure in China, several innovative soil improvement methods have been developed in recent years. In this paper, three methods that are applicable to the improvement of soft ground, namely the vacuum preloading method, the explosive replacement method and the dynamic consolidation method, are introduced. Case studies are presented to illustrate the applications of each method in road or runway constructions. The principles and techniques related to each method are explained. The advantages and disadvantages of each method are discussed and compared. The limitations of each method are also highlighted. Pour faire face aux développements gigantesques de l'infrastructure de transport en Chine, plusieurs méthodes innovantes pour l'lamélioration des sols ont été développées ces dernières années. Dans cet exposé, nous présentons trois méthodes qui sont applicables à l'amélioration de sols tendres, nommément la méthode de précharge sous vide, la méthode de remplacement explosif et la méthode de consolidation dynamique. Nous présentons des études de cas pour illustrer les applications de chaque méthode à la construction de routes ou de pistes de décollage. Nous expliquons les principes et techniques liés à chacune de ces méthodes. Nous analysons et comparons leurs avantages et leurs inconvénients. Nous montrons aussi leurs limitations.
Coreflood Studies Examine New Technologies That Minimize Intervention Throughout Well Life Cycle
Authors: Jordan M. M. , Collins I. R. , Gyani A. , Graham G. M. 
Published: May 2006

Summary
With the development of more and more subsea fields, the challenge for scale-inhibitor squeeze treatments is to reduce intervention frequency by extending squeeze treatment lifetime while con-comitantly reducing any potential damage in both low water-cut and high water-cut wells. This paper discusses the technical problems and examines new technologies for treatment of such production wells through their life cycle. This paper covers the findings from late 2001 through early 2002. Because even newer technologies have been developed since the writing of this paper, it should be read as the history of technological development.
Scale control technology available to control scale formation within the reservoir and near-wellbore area of production wells will be outlined with a focus on the current developing technology to control scale within low water-cut wells. Moreover, this paper shows that the new technical area of emulsion-scale-inhibitor-delivery systems, originally designed to control scale within low water-cut wells, has applications in both low and high water-cut wells.
This study assists in developing an understanding of the mechanism of interaction of emulsion-based products—in particular, the impact of the level of water saturation within the core system. In addition, it demonstrates that the emulsion particles are retained in the core matrix during both crude and brine flowback. This paper indicates that the emulsion product offers the potential for extremely long squeeze lifetimes with minimal damage in oil-production wells with rising water cut. It also demonstrates how different technologies have their own place in the life cycle of a production well.
Consideration of Damaged Zone in a Tight Gas Reservoir Model With a Hydraulically Fractured Well
Authors: Behr Aron , Mtchedlishvili George , Friedel Torsten , Haefner Frieder 
Published: May 2006

Summary
This paper provides a detailed description of conditions in the hydraulically damaged fracture environment after closure and how to integrate them into a reservoir-simulation model.
A special model-initialization algorithm was developed and realized in a support tool to make possible the computing of a post-fracture performance in tight gas formations by a reservoir simulator. The input represents the treatment schedule of the fracturing process and some results produced by commercial fracturing packages or geophysical measurements.
To represent the fracture geometry and properties, the information about the distribution of the proppant concentration in the fracture as well as the fracture-width variation is translated into the permeabilities and porosities of the fracture gridblocks. To determine the fracturing-fluid saturation in the invaded zone, a new approach was derived to imitate the fracture propagation at a fracturing period under consideration of the leakoff processes. The penetration of the fracturing fluid into the matrix was modeled by the Buckley-Leverett equations for two-phase nonmiscible displacement, with boundary conditions provided by a classical leak-off theory.
The approach is illustrated with a simulation model prepared for the analysis of the cleanup process in a damaged fractured well within a Rotliegende tight gas formation in north Germany.
A Novel Laboratory Method for Assessing the Erosional Characteristics of Mudcakes
Authors: Amanullah Md. 
Published: May 2006

Summary
Design and development of superior drilling and drill-in fluids and the assessment of the effectiveness of mudcake cleaning from the borehole wall by cleaning systems require a good understanding of the fundamental phenomena associated with the erosional behavior of mudcakes formed by different mud systems. Because of serious consequences of mudcake erosion on the formation damage potential of drilling muds and mudcake cleaning before a cementation job, it is important to have a suitable, simple, and field-applicable method for predicting the erosional potential of mudcakes formed by muds of different chemical composition. The prediction of erosion behavior is essential to screen and select appropriate mud additives and also to design new mud products for producing good-quality mudcakes on the borehole wall. The technique and technology could provide a suitable means to assess the effectiveness of mudcake cleaning systems and to help design such cleaning systems for removal of mudcake from the borehole wall.
Cakes formed by several water-based muds were evaluated using the newly developed technique. The testing has been performed with the simulation of hydrodynamic conditions corresponding to the drill-collar borehole-annular section of a wellbore. The results indicate that the presence of electrolytes significantly increases the erosion coefficient of bentonite mudcake. Ionic fluid-loss additives such as polyanionic cellulose (PAC) and carboxy-methyl cellulose (CMC) reduced the erosion behavior of saltwater-based bentonite mudcake significantly. However, the presence of the polyanionic fluid-loss additive PAC caused a drastic reduction in the erosion characteristic of NaCl-based saltwater mud compared to the presence of the anionic fluid-loss additive CMC. The presence of the nonionic fluid-loss additive, modified starch, shows little improvement of erosional behavior of saltwater-based mudcake. It seems to be that the electrochemical forces of interactions of ionic fluid-loss additives play a vital role in making a mudcake nonerodible. The variation of the erosional characteristics of the mudcakes is attributable to the physical, chemical, and electrical properties of the cake-forming mud additives and also to the nature of the fabrics formed by these additives within the mudcake matrix.
Impact on Scale Management of the Engineered Depressurization of Waterflooded Reservoirs: Risk Assessment Principles and Case Study
Authors: Chekani M. , Mackay E. J. 
Published: May 2006

Summary
Increased oil and particularly gas production may be achieved in waterflooded reservoirs by stopping further water injection and depressurizing the reservoir to release solution gas. Pressure depletion may be accelerated by backproducing injected brines. However, there is the possibility that these brines may cause formation damage by mobilizing fines or deposition of inorganic scales. Scale deposition in production wells may also occur as a result of pressure depletion, with calcite scales being precipitated when the system drops below the CO2 bubblepoint pressure. This paper discusses the assessment and prediction of scale-related formation damage problems that are likely to occur during depressurization of a case study field. The potential for the specific problem arises from the formation of barium sulfate scale as a result of mixing of injected and formation brines during production. Data used in this study include well brine chemistries and an existing finite-difference reservoir simulation model of the field depressurization, which was used to calculate the mixing of injected and formation brines and the movement of the mixing and temperature fronts during waterflooding and subsequent depressurization.
This study has determined that the behavior of the scaling potential for each well in this field is different. Also, the degree of scaling, both deep within the reservoir where it does the least damage and around the wellbore (for both injectors and producers) where it may adversely affect production, can be predicted by detailed modeling using both conventional and reaction flow simulations. Former injectors converted to water production or infill wells drilled in the aquifer for pressure depletion may experience an increase in the scaling potential that significantly impacts the economics of the project because of the need for extensive prevention (inhibition) treatments. The increased scaling potential in these wells is a result of the dynamics of brine mixing in the reservoir, the lowering of reservoir temperature in the vicinity of injection wells during waterflooding, and the large volumes of water required to be produced to achieve depressurization. The magnitude of the scaling problem and the economic impact are lower for the production wells because of lower water production rates and higher temperatures.
Optimization of Commingled Production Using Infinitely Variable Inflow Control Valves
Authors: Naus N. M. J. J. , Dolle N. , Jansen J. -D. 
Published: May 2006

SummaryWe developed an operational strategy for commingled production with infinitely variable inflow control valves (ICVs) using sequential linear programming (SLP). The optimization algorithm requires instantaneous and derivative information. We propose a workflow in which the production engineer relies on measurements to determine the flow rate and pressure values and on models to determine the derivative information (i.e., the changes in flow rates as a result of a change in an ICV setting). Such a model typically would be a steady-state wellbore simulator including choke models to represent the ICVs and inflow models to represent the near-well reservoir flow in the various zones. The parameters of the model need to be updated regularly using real-time measurements and production tests, and we discuss the impact of different smart-well instrumentation levels on the updating process.We simulated the performance of this production-optimization strategy in a reservoir simulator. Some numerical aspects of the algorithm and problems encountered during implementation are discussed. The performance of the algorithm was tested in two reservoir settings. In both cases, the optimization resulted in accelerated oil production compared to conventional, surface-controlled production. However, accelerated production did not always result in higher ultimate recovery compared to the conventional case. In such situations, the benefits of either short-term production optimization (accelerating production) or long-term reservoir management (maximizing recovery) should be weighed.
Jüngste Entwicklungen in der Metallabenzolchemie
Authors: Landorf Christopher W. , Haley Michael M. 
Published: May 2006

AbstractAromatische Metallacyclen sind zwar bereits seit 25 Jahren bekannt, seit dem Jahr 2000 hat dieses Forschungsgebiet aber einen deutlichen Aufschwung genommen. Dank neuer Synthesemethoden ist heute eine Vielzahl von Metallabenzolen zugänglich, die auch zuvor nicht vertretene Metallzentren enthalten. Aromatische Metallacyclen mit neuartigen Strukturen – Iridanaphthaline und Osmabenzine – wurden isoliert und charakterisiert. Die ersten Valenzisomere von Metallabenzolen – Iridabenzvalene und Rhodabenzvalene – wurden ebenso erhalten wie Konstitutionsisomere – die Isoosmabenzole. Der Aufsatz beschreibt die Synthese, die chemische Reaktivität und die physikalischen Eigenschaften dieser außergewöhnlichen aromatischen Verbindungen.
Recent Advances in Metallabenzene Chemistry
Authors: Landorf Christopher W. , Haley Michael M. 
Published: May 2006

AbstractResearch into aromatic metallacycles, though discussed in the literature over the last quarter century, has undergone a major expansion since 2000. A wide variety of new metallabenzenes, encompassing new synthetic methods and new metal centers, is now available. New aromatic metallacycle topologies (iridanaphthalene, osmabenzynes) have been isolated and characterized. The first metallabenzene valence isomers (iridabenzvalenes, rhodabenzvalenes) and constitutional isomers (isoosmabenzenes) are now known. This review discusses the synthesis, chemistry, and physical properties of these intriguing aromatic compounds.
Determination of degradation rate of acrylonitrile polymers
Authors: Hou Chen , Qu Rongjun , Qun Wang , Ying Liang 
Published: May 2006

AbstractLow‐temperature degradations of acrylonitrile homopolymers and acrylonitrile/acrylamide copolymers in air were investigated by IR and thermogravimetry. The degradation rates of acrylonitrile polymers were determined by measurement of normalized absorbance of CN band and effects of the degradation temperature, time, and comonomer on the rate of degradations were discussed. It was found that the polymers start to degrade as the temperature increased to 150°C. In the temperature range of 180–210°C, values of the rate of polymer degradation were maximal and the rate of degradation of acrylonitrile/acrylamide copolymers was higher compared with that of acrylonitrile homopolymers. At 150°C, acrylonitrile homopolymers had an induction period of about 0.5 h. The rate of degradation of acrylonitrile/acrylamide copolymers showed an obvious trend of increase along with acrylamide concentration, and changes of the rate became less prominent as the weight ratio of acrylamide/acrylonitrile went beyond 5/95. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1511–1514, 2006
Improvement of processability of clay/polylactide nanocomposites by a combinational method: In situ polymerization of L‐lactide and melt compounding of polylactide
Authors: Lee Seongnam , Kim Chang‐Hyeon , Park Jung‐Ki 
Published: May 2006

AbstractA modified clay/polylactide nanocomposite was prepared. The clay was modified by grafting polylactide chains onto the surface of clay. The modified clay was melt‐compounded with a high‐molecular‐weight polylactide matrix. This novel clay/polylactide nanocomposite showed high shear‐thinning behavior when the molecular weight of the grafted poly(L‐lactide) was rather high. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1664–1669, 2006
Thermal analysis and mechanical characterization of maleimide‐functionalized benzoxazine/epoxy copolymers
Authors: Ishida Hatsuo , Ohba Sharon 
Published: May 2006

AbstractMaleimide‐functionalized benzoxazine is copolymerized with epoxy to improve toughness and processibility without compromising the thermal properties. The incorporation of maleimide functionality into the benzoxazine monomer results in a high performance polymer. All three possible polymerization reactions are confirmed using Fourier transform infrared (FT‐IR) spectroscopy. While maleimide‐functionalized benzoxazine has a glass transition temperature, Tg, of 252°C, a further 25°C increase of Tg is observed when copolymerized with epoxy. The flexural properties are also measured, and the copolymers exhibit a flexural modulus of 4.2–5.0 GPa. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1670–1677, 2006
Tribological properties of micro‐ and nanoparticles‐filled poly(etherimide) composites
Authors: Xian Guijun , Zhang Zhong , Friedrich Klaus 
Published: May 2006

AbstractIt has been found that nano‐ or microsized inorganic particles in general enhance the tribological properties of polymer materials. In the present study, 5 vol % nano‐TiO2 or micro‐CaSiO3 was introduced into a polyetherimide (PEI) matrix composite, which was filled additionally with short carbon fibers (SCF) and graphite flakes. The influence of these inorganic particles on the sliding behavior was investigated with a pin‐on‐disc testing rig at room temperature and 150°C. Experimental results showed that both particles could reduce the wear rate and the frictional coefficient (μ) of the PEI composites under the applied testing conditions. At room temperature, the microparticles‐filled composites exhibited a lower wear rate and μ, while the nano‐TiO2‐filled composites possessed the lowest wear rate and μ at elevated temperature. Enhancement in tribological properties with the addition of the nano‐particles was attributed to the formation of transfer layers on both sliding surfaces together with the reinforcing effect. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1678–1686, 2006