bluuebunny/crossref_metadata_2025 huggingface dataset:
Potential Futures for Russian Natural Gas Exports
Authors: Hartley Peter R. , Medlock Kenneth B.
Published: May 2011

Russia is a dominant supplier of natural gas, especially to Europe, and has the resources to become even more dominant in the future. Nevertheless, we show that Russia’s ability to influence the world natural gas market is limited in the longer term by competition from alternative suppliers.
Cross Border Trading and Borrowing in the EU ETS
Authors: Ellerman A. Denny , Trotignon Raphael
Published: May 2011

This paper exploits a little used data resource within the central registry of the European Union’s Emissions Trading System (EU ETS) to analyze cross border trading and inter-year borrowing during the first trading period (20052007). Cross-border flows were small in the aggregate but remarkably frequent in matching allowance deficits and surpluses at the installation level throughout the EU. These data also indicate that a novel feature of the EU ETS—the ability to borrow allowances from the forward allocation to satisfy current compliance requirements—was also used. These data provide evidence that the precondition of efficient abatement in a cap-and-trade system—widespread use of trading opportunities—was present in the first period of the EU ETS.
Electricity Retailing in Norway
Authors: von der Fehr Nils-Henrik M. , Hansen Petter Vegard
Published: May 2011

We analyze retailer and household behavior on the Norwegian electricity market, based on detailed information on prices and other market characteristics. We find that there exists a competitive market segment where a number of retailers compete fiercely for customers, with small margins on all products. However, we also find indications of monopolistic behavior, whereby retailers exploit the passivity of some of their customers. We discuss potential explanations for these results.
Bilateral Forward Contracts and Spot Prices
Authors: Adilov Nodir
Published: May 2011

Allaz and Vila (1993) have shown that forward markets could mitigate market power and improve efficiency. This paper shows that efficiency-improving effect of forward markets is sensitive to the assumption that market participants behave like rational expectations agents when forecasting prices. The existence of forward contracts could increase spot prices and hurt efficiency if buyers engage in bilateral forward contracts and forward rates are influenced by historic prices. These findings have important policy implications for the electricity industry.
Why Do States Adopt Renewable Portfolio Standards?: An Empirical Investigation
Authors: Lyon Thomas P. , Yin Haitao
Published: May 2011

Renewable portfolio standards (RPSs) for electricity generation are politically popular in many U.S. states although economic analysis suggests they are not first-best policies. We present an empirical analysis of the political and economic factors that drive state governments to adopt an RPS, and the factors that lead to the inclusion of in-state requirements given the adoption of an RPS. Although advocates claim an RPS will stimulate job growth, we find that states with high unemployment rates are slower to adopt an RPS. Local environmental conditions and preferences have no significant effect on the timing of adoption. Overall, RPS adoption seems to be driven more by political ideology and private interests than by local environmental and employment benefits, raising questions as to when environmental federalism serves the public interest.
International Evidence on Sectoral Interfuel Substitution
Authors: Serletis Apostolos , Timilsina Govinda R. , Vasetsky Olexandr
Published: May 2011

This paper estimates interfuel substitution elasticities in selected developing and industrialized economies at the sector level. In doing so, it employs state-of-the-art techniques in microeconometrics, particularly the locally flexible normalized quadratic functional form, and provides evidence consistent with neoclassical microeconomic theory. The results indicate that the interfuel substitution elasticities are consistently below unity, revealing the limited ability to substitute between major energy commodities (i.e., coal, oil, gas, and electricity). We find that on average, industrial and residential sectors tend to exhibit higher potential for substitution between energy inputs as compared to the electricity generation and transportation sectors in all countries, with the United States being the only exception. In addition, we find that developed countries demonstrate higher potential for interfuel substitution in their industrial and transportation sectors as compared to the developing economies. The implication is that interfuel substitution depends on the structure of the economy, not the level of economic development. Moreover, higher changes in relative prices are needed than what we have already experienced to induce switching toward a lower carbon economy.
Modeling and Analysis of the International Steam Coal Trade
Authors: Haftendorn Clemens , Holz Franziska
Published: May 2011

Coal continues to play an important role in the global energy sector and with the increase in international trade a global market for steam coal has developed. We investigate market structure and recent price developments with a numerical modeling approach and develop two partial equilibrium models, a quantity based model and a model additionally incorporating energy values. We compare two possible market structure scenarios for the years 2005 and 2006: perfect competition and Cournot competition. Our chief finding is that, for both models, the simulation of perfect competition better fits the observed real market flows and prices. However, we also note that spatial price discrimination and a time lag in the pricing-in of capacity constraints are additional mechanisms in the market. From a modeling perspective, relying only on coal quantities leads to distortions in estimated trade flows, suggesting that an energy-based model is superior.
Managing the Low-Carbon Transition - From Model Results to Policies
Authors: Knopf Brigitte , Edenhofer Ottmar , Flachsland Christian , Kok Marcel T. J. , Lotze-Campen Hermann , Luderer Gunnar , Popp Alexander , van Vuuren Detlef P.
Published: May 2011

Model analysis within the ADAM project has shown that achieving low greenhouse gas concentration levels, e.g. at 400ppm CO2-eq, is technologically feasible at costs of a few percent of GDP. However, models simplify the dynamics involved in implementing climate policy and the results depend on critical model assumptions such as global participation in climate policy and full availability of current and newly evolving technologies. The design of a low stabilization policy regime in the real world depends on factors that can only be partly covered by models. In this context, the paper reflects on limits of the integrated assessment models used to explore climate policy and addresses the issues of (i) how global participation might be achieved, (ii) which kind of options are available to induce deep GHG reductions inside and outside the energy sector, and (iii) which risks and which co-benefits of mitigation options are not assessed by the models.
A Dynamic Incentive Mechanism for Transmission Expansion in Electricity Networks: Theory, Modeling, and Application
Authors: Rosellón Juan , Weigt Hannes
Published: May 2011

We propose a price-cap mechanism for electricity-transmission expansion based on redefining transmission output in terms of financial transmission rights. Our mechanism applies the incentive-regulation logic of rebalancing a two-part tariff. First, we test this mechanism in a three-node network. We show that the mechanism intertemporally promotes an investment pattern that relieves congestion, increases welfare, augments the Transco’sprofits, and induces convergence of prices to marginal costs. We then apply the mechanism to a grid of northwestern Europe and show a gradual convergence toward a common-price benchmark, an increase in total capacity, and convergence toward the welfare optimum.
Strategic Forward Contracting in the Wholesale Electricity Market
Authors: Holmberg Par
Published: May 2011

This paper analyses a wholesale electricity market with supply function competition. Trade in the forward and spot markets is represented by a two-stage game, and its subgame perfect Nash equilibrium (SPNE) is characterized. It is verified that increased forward sales of a producer constitute a credible commitment to aggressive spot market bidding. The paper identifies market situations when this pro-competitive commitment is unilaterally profitable for the producer. It is also proven that a producer has incentives to sell in the forward market in order to reduce competitors’ forward sales, which softens their spot market offers.
Energy Demand and Energy Efficiency in the OECD Countries: A Stochastic Demand Frontier Approach
Authors: Filippini Massimo , Hunt Lester C.
Published: May 2011

This paper attempts to estimate a panel “frontier” whole economy aggregate energy demand function for 29 countries over the period 1978 to 2006 using parametric stochastic frontier analysis (SFA). Consequently, unlike standard energy demand econometric estimation, the energy efficiency of each country is also modeled and it is argued that this represents a measure of the underlying efficiency for each country over time, as well as the relative efficiency across the 29 OECD countries. This shows that energy intensity is not necessarily a good indicator of energy efficiency, whereas by controlling for a range of economic and other factors, the measure of energy efficiency obtained via this approach is. This is, as far as is known, the first attempt to econometrically model OECD energy demand and efficiency in this way and it is arguably particularly relevant in a world dominated by environmental concerns with the subsequent need to conserve energy and/or use it as efficiently as possible. Moreover, the results show that although for a number of countries the change in energy intensity over time might give a reasonable indication of efficiency improvements; this is not always the case. Therefore, unless this analysis is undertaken, it is not possible to know whether the energy intensity of a country is a good proxy for energy efficiency or not. Hence, it is argued that this analysis should be undertaken to avoid potentially misleading advice to policy makers.
Understanding Middle East Gas Exporting Behavior
Authors: Wietfeld Axel M.
Published: May 2011

The Middle East is a fascinating region with an immense GDP growth and an excellent business environment. Thanks to its huge hydrocarbon reserves, the region already exports a lot of oil and gas and has realistic plans to increase this further. Although the global gas market is currently saturated and will be so for the next years, the hunger for additional supplies is likely to reappear in the second half of the new decade. Consequently, the gas exporting nations in the Middle East, such as Qatar, the UAE, Oman and Iran have to prepare themselves for developing additional projects. The question discussed in this article is whether they are able to do so, given challenges such as high indigenous demand, energy inefficiency, reserve structures and the sometimes unstable political environment, which is making it difficult to attract the required capital.

This review begins with a brief overview of each country’s reserve structure and natural gas history. It then proceeds to analyze the current and future supply/demand balance, taking into account the relevant pipeline andLNG export projects, and draws conclusions for future export projects.

The results suggest that Qatar, the UAE, Iran and Oman could contribute to global LNG and pipeline gas supplies with additional volumes of 55 to 90 bcm/a in the period 2015 to 2020.
The Simple Economics of Industrial Cogeneration
Authors: Josknv Paul L. , Jones Donald R.
Published: May 2011

Rising energy prices and dependence on insecure supplies of foreign petroleum have led energy consumers and energy policymakers to seek methods to use energy more efficiently. Industrial cogeneration has frequently been seen as such a method. By generating electricity in conjunction with the production of steam for industrial processes, less energy is used than when process steam and electricity are produced separately. Most recent U.S. energy policy studies have spoken favorably about the potential for cogeneration.' Some specific studies have indicated opportunities to replace central station electric power generation with industrial cogeneration capacity, and, in the process, to reduce domestic energy consumption substantially.
Comment on "Optimal Oil Producer Behavior Considering Macrofeedbacks"
Authors: Mork Knut Anton
Published: May 2011

Harry Saunders's paper on the above subject in this issue of the Journal raises a very interesting point. As is well known, oil-exporting countries now hold major assets in the Western economies. Furthermore, the sensitivity of these economies to abrupt changes in oil prices seems widely accepted. It then seems reasonable to expect oil exporters' pricing decisions to be influenced by concerns about the rate of return on their assets. In particular, Saunders argues that oil exporters would want to avoid abrupt price changes because the ensuing shock effects would tend to reduce the rate of return on capital.
Analysis of Technological Portfolios for C02 Stabilizations and Effects of Technological Changes
Authors: Sano Fuminori , Akimoto Keigo , Homma Takashi , Tomoda Toshimasa
Published: May 2011

In this study, cost-effective technological options to stabilize CO2 concentrations at 550, 500, and 450 ppmv are evaluated using a world energy systems model of linear programming with a high regional resolution. This model treats technological change endogenously for wind power, photovoltaics, and fuel-cell vehicles, which are technologies of mass production and are considered to follow the “learning by doing” process. Technological changes induced by climate policies are evaluated by maintaining the technological changes at the levels of the base case wherein there is no climate policy. The results achieved through model analyses ixnclude 1) cost-effective technological portfolios, including carbon capture and storage, marginal CO2 reduction costs, and increases in energy system cost for three levels of stabilization and 2) the effect of the induced technological change on the above mentioned factors. A sensitivity analysis is conducted with respect to the learning rate.
Comparison of Climate Policies in the ENTICE-BR Model
Authors: Popp David
Published: May 2011

This paper uses the ENTICE-BR model to study the effects of various climate stabilization policies. Because the ENTICE-BR model includes benefits from reduced climate damages, it is possible to calculate the net economic impact of each policy. In general, only the least restrictive concentration limit is welfare enhancing. While the policies are welfare enhancing in simulations using optimistic assumptions about the potential of the backstop energy technology, such assumptions mean that the backstop is also used in the no-policy base case, so that climate change itself is less of a problem. Finally, assumptions about the nature of R&D markets are important. Removing the assumption of partial crowding out from energy R&D nearly doubles the gains from policy-induced energy R&D.
Combining Energy Technology Dynamics and Macroeconometrics: The E3MG Model
Authors: Köhler Jonathan , Barker Terry , Anderson Dennis , Pan Haoran
Published: May 2011

This paper introduces a novel approach to the hybrid modelling of technological change climate stabilisation cost literature. We describe how a post-Keynesian macroeconomic model of sectoral demand, E3MG, has been combined with investments in 26 energy technologies from a submodel, ETM. E3MG is a 20-region global energy-environment-economy (E3) econometric, dynamic simulation model. It is a component of the UK Tyndall Center’s Community Integrated Assessment System. Technological change is endogenous, through its effects on general energy use and sectoral demand, and on energy technologies through the cost-reducing effects o f learning by doing and economies of scale. This approach directly challenges the notion that historically estimated models cannot be use for long-term analysis. The paper concludes with an account of how technological progress is induced in this hybrid system by high relative prices of carbon designed to achieve climate stabilization at 450ppmv.
Long-Term Multi-Gas Scenarios to Stabilise Radiative Forcing - Exploring Costs and Benefits Within an Integrated Assessment Framework
Authors: Vuuren D.P.van , Eickhout B. , Lucas P.L. , Elzen M.G.J.den
Published: May 2011

This paper presents a set of multi-gas mitigation scenarios that aim for stabilisation of greenhouse gas radiative forcing in 2150 at levels from 3.7 to 5.3 W/m2. At the moment, non-CO2 gasses (methane, nitrous oxide, PFCs, HFCs and SF6) contribute to about a quarter of the global emissions. The analysis shows that including these non-CO2 gases in mitigation analysis is crucial in formulating a cost-effective response. For stabilisation at 4.5 W/m2, a multi-gas approach leads to 40% lower costs than an approach that would focus at CO2-only. Within the assumptions used in this study, the non-CO2 gasses contribution to total reduction is very large under less stringent targets (up to 60%), but declines under stringent targets. While stabilising at 3.7 W/m2 obviously leads to larger environmental benefits than the 4.5 W/m2 case (temperature increase in 2100 are 1.9 and 2.3oC, respectively), the costs of the lower target are higher (0.80% and 0.34% of GDP in 2100, respectively). Improving knowledge on how future reduction potential for non-CO2 gasses could develop is shown to be a crucial research question.
The Role of Non-CO2 Greenhouse Gases in Climate Change Mitigation: Long-term Scenarios for the 21st Century
Authors: Rao Shilpa , Riahi Keywan
Published: May 2011

The non-CO2 greenhouse gases have so far jointly contributed around 40 percent to overall global warming. In this paper we examine the role of non-CO2 greenhouse gases in meeting long-term climate change targets. For this purpose, we develop climate mitigation scenarios aimed at achieving long-term stabilization of global radiative forcing. We use the MESSAGE model for a thorough bottom-up representation of the six Kyoto greenhouse gases and corresponding mitigation technologies. This approach endogenizes energy feedback effects from mitigation of non-CO2 gases and takes into account the interplay and side benefits that exist across GHGs. We analyze two mitigation scenarios that stabilize global radiative forcing at 4.5 W/m2 as compared to pre-industrial times—one allowing only for CO2 mitigation and another with multigas mitigation. In addition, we also investigate a lower stabilization level of 3 W/m2 and look into the implications this has for abatement strategies. Our approach helps us to identify a portfolio of measures in the energy, industry and agricultural sectors for achieving a proposed climate target. We find that considering the full basket of GHGs improves the effectiveness of the mitigation portfolio resulting in significantly lower costs, especially in the short term. In the long run, the bulk of the emissions reductions are still found to come from CO2 and this effect becomes more pronounced under the more stringent climate target. This emphasizes the importance of a diverse mitigation portfolio that includes both CO2 and non-CO2 related abatement options in meeting long-term climate targets.
Enhanced DNA Sequencing Performance Through Edge‐Hydrogenation of Graphene Electrodes
Authors: He Yuhui , Scheicher Ralph H. , Grigoriev Anton , Ahuja Rajeev , Long Shibing , Huo ZongLiang , Liu Ming
Published: May 2011

The use of graphene electrodes with hydrogenated edges for solid‐state nanopore‐based DNA sequencing is proposed, and molecular dynamics simulations in conjunction with electronic transport calculations are performed to explore the potential merits of this idea. The results of the investigation show that, compared to the unhydrogenated system, edge‐hydrogenated graphene electrodes facilitate the temporary formation of H‐bonds with suitable atomic sites in the translocating DNA molecule. As a consequence, the average conductivity is drastically raised by about 3 orders of magnitude while exhibiting significantly reduced statistical variance. Furthermore, the effect of the distance between opposing electrodes is investigated and two regimes identified: for narrow electrode separation, the mere hindrance due to the presence of protruding hydrogen atoms in the nanopore is deemed more important, while for wider electrode separation, the formation of H‐bonds becomes the dominant effect. Based on these findings, it is concluded that hydrogenation of graphene electrode edges represents a promising approach to reduce the translocation speed of DNA through the nanopore and substantially improve the accuracy of the measurement process for whole‐genome sequencing.
Analysis of the hydrogenotrophic microbiota of wild and captive black howler monkeys (Alouatta pigra) in palenque national park, Mexico
Authors: Nakamura Noriko , Amato Katherine R. , Garber Paul , Estrada Alejandro , Mackie Roderick I. , Gaskins H. Rex
Published: May 2011

Intestinal methanogenesis is one of the major pathways for consumption of hydrogen produced by bacterial fermentation and is considered to affect the efficiency of host energy harvest; however, little information is available regarding the hydrogenotrophic pathways of nonhuman primates in the wild, in general, and of howler monkeys, in particular. Microbial fermentation of plant structural carbohydrates is an important feature in wild howlers owing to the high fiber and low available energy content of leaves, which make up the primary component of their diet. In contrast, captive howlers may consume greater quantities of fruits and vegetables that are higher in water, lower in fiber, and, along with commercial monkey chow commonly added to captive monkey diets, more readily digestible than the natural diet. In this study, we analyzed the composition of methanogens and sulfate‐reducing bacteria (SRB) from fecal samples of black howler monkeys (Alouatta pigra) in the wild and in captivity. The hydrogenotrophic microbiota of three groups of monkeys was evaluated by PCR‐denaturing gradient gel electrophoresis (DGGE) fingerprinting, small clone library construction, and quantitative real‐time PCR. Abundance of methanogens was lower than SRB in all howler monkey groups studied. DGGE banding patterns were highly similar within each wild and captive group but distinct among groups. Desulfovibrionales‐enriched DGGE showed reduced microbial diversity in the captive animals compared with their wild counterparts. Taken together, the data demonstrate that environmental or dietary changes of the host imposed by captivity likely influence the composition of intestinal hydrogenotrophs in black howler monkeys. Am. J. Primatol. 73:909–919, 2011. © 2011 Wiley‐Liss, Inc.
A meta‐analysis of topical amphotericin B for the treatment of chronic rhinosinusitis
Authors: Isaacs Seth , Fakhri Samer , Luong Amber , Citardi Martin J.
Published: May 2011

Background

Fungal species have been implicated in the pathophysiology of chronic rhinosinusitis (CRS). Based on this observation, some clinicians have employed topical antifungal therapy with amphotericin B (AMB); however, its efficacy has not been consistently supported by the literature.

Methods

A comprehensive review of the English‐language literature on the role of topical AMB therapy in CRS treatment was performed. Search criteria included placebo‐controlled trials between the years of 2000 and 2009. Studies that reported outcomes based on computed tomography (CT), nasal endoscopy (NE), and symptom scores (SS) were included.

Results

Three published studies reported CT outcomes. After pooling patients from these 3 studies, meta‐analysis revealed no significant difference between AMB‐treated and control groups (p = 0.07). Four studies reported NE outcomes, in which central tendency (mean or median) and variance were identified. Among these 4 studies, combining AMB‐treated patients did not reveal any significant effect when compared to the small control group (p = 0.53). Only 2 studies reported SS; no significant differences in symptoms were noted (p = 0.33).

Conclusion

A systematic review of the literature does not support the use of topical AMB for the treatment of CRS. © 2011 ARS‐AAOA, LLC.
Efficacy and safety of azelastine 0.15% nasal spray administered once daily in patients with allergy to Texas mountain cedar pollen
Authors: Howland William C. , Amar Niran J. , Wheeler William , Sacks Harry
Published: May 2011

Background

A previous study with azelastine nasal spray in patients with seasonal allergic rhinitis (SAR) demonstrated that increasing the azelastine concentration from 0.1% to 0.15% allowed for once‐daily dosing without increasing the incidence of adverse effects. This study evaluated the efficacy of azelastine 0.15% nasal spray administered once daily for treating symptoms of SAR.

Methods

In this 14‐day, randomized, double‐blind, placebo‐controlled study, patients with moderate‐to‐severe SAR were randomized to azelastine 0.15% (n = 251) or placebo (n = 255), both at a dosage of 2 sprays/nostril once daily. The primary efficacy variable was change from baseline in the 12‐hour reflective Total Nasal Symptom Score (TNSS). Key secondary variables were change from baseline in 24‐hour instantaneous TNSS, to establish the dosing interval, and change from baseline in the Total Ocular Symptom Score (TOSS).

Results

The mean improvement (3.57) and percentage improvement (19.3%) in 12‐hour reflective TNSS was significant (p < 0.012) with azelastine 0.15% compared to placebo (2.14 and 11.4%, respectively). The mean improvement in 24‐hour instantaneous TNSS was also significant (p < 0.001) for azelastine 0.15% compared to placebo, indicating efficacy with once‐daily dosing. The overall improvement and percentage improvement in TOSS was significant (p ≤ 0.012) with azelastine 0.15% (2.21 and 16.7%, respectively) compared to placebo (1.28 and 6.0%, respectively). The overall score for the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) was significantly (p < 0.001) improved from baseline in the azelastine group compared with the placebo group. Nasal discomfort (3.6%) and bitter taste (2.4%) were the most common adverse events. There were no reports of somnolence with azelastine.

Conclusion

Azelastine 0.15% was effective and well tolerated with once‐daily dosing. Azelastine 0.15% nasal spray significantly improved a complex of eye symptoms compared to placebo. © 2011 ARS‐AAOA, LLC.
A crime reports analysis system to identify related crimes
Authors: Ku Chih‐Hao , Leroy Gondy
Published: May 2011

The popularity of online and anonymous options to report crimes, such as tips websites and text messaging, has led to an increasing amount of textual information available to law enforcement personnel. However, locating, filtering, extracting, and combining information to solve crimes is a time‐consuming task. In response, we are developing entity and document similarity algorithms to automatically identify overlapping and complementary information. These are essential components for systems that combine and contrast crime information. The entity similarity algorithm integrates a domain‐specific hierarchical lexicon with Jaccard coefficients. The document similarity algorithm combines the entity similarity scores using a Dice coefficient. We describe the evaluation of both components. To evaluate the entity similarity algorithm, we compared the new algorithm and four generic algorithms with a gold standard. The strongest correlation with the gold standard, r = 0.710, was found with our entity similarity algorithm. To evaluate the document similarity algorithm, we first developed a test bed containing witness reports for 17 crimes shown in video clips. We evaluated five versions of the algorithm that differ in how much importance is assigned to different entity types. Cosine similarity is then used as a baseline comparison to evaluate the performance of the document similarity algorithms for accuracy in recognizing reports describing the same crime and distinguishing them from reports on different crimes. The best version achieved 92% accuracy.
Modeling and control of a feed drive with multiple mechanically coupled ball screws
Authors: Hsieh Min‐Fu , Yao Wu‐Sung , Hsu Chun‐Hao
Published: May 2011

This paper presents the modeling and control of a single‐axis feed drive that is jointly driven by three ball screw/motor units. These ball screws are bridged by a mechanical coupling, via which a joint thrust can be produced from the three drive units for high‐power output (e.g., injection molding machines). Synchronous positioning of these drive units can also be applied to the handling of large workpieces. For such a coupled system, a mathematical model is first derived and constructed using a system identification technique developed in this paper. A control scheme based on the master–slave control is then designed to improve the system performance with the mechanical coupling. To ensure synchronization of the three drive units, a synchronous compensator is also designed using the genetic algorithm. Finally, the performance of the entire control system is experimentally verified.

Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Umbau des polyhistorischen Wissensraums. Johann Christoph Stockhausens Critischer Entwurf einer auserlesenen Bibliothek für den Liebhaber der Philosophie und schönen Wissenschaften (1752)
Authors: Werle Dirk
Published: May 2011

The Polyhistorian Space of Knowledge Re‐Organized: Johann Christoph Stockhausen's Critischer Entwurf einer auserlesenen Bibliothek für den Liebhaber der Philosophie und schönen Wissenschaften (1752). The example of Johann Christoph Stockhausen's Critischer Entwurf einer auserlesenen Bibliothek für den Liebhaber der Philosophie und schönen Wissenschaften shows how the space of learned knowledge – in the literal and metaphorical sense – is reorganized around the middle of the 18th century. The traditional polyhistorian order of knowledge gradually integrates elements of enlightened scholarship without completely giving up the old ideals. Considering the background of this process, Stockhausen is anything but a polyhistorian latecomer; on the contrary he has to be seen as a pragmatic theoretician trying to render learned knowledge sustainable in a changing world of scholarship. His outline of an ideal library, compared with its forerunners, is distinguished by a more pragmatic perspective and a virtualized concept of the library. He still operates with traditional topoi, but, at the same time, uses an innovative guiding semantics, within which the catchword ‘critical’ plays a central role.
Cathodic electrochemiluminescence of the peroxydisulphate–ciprofloxacin system and its analytical applications
Authors: Liang Yao‐Dong , Yu Chun‐Xia , Song Jun‐Feng
Published: May 2011

The cathodic electrochemiluminescence (ECL) of peroxydisulphate (S2O82−)–ciprofloxacin (CPF) system at a wax‐impregnated graphite electrode was studied. When CPF was absent, S2O82− was electrochemically reduced to sulphate free radical (SO4•−), and dissolved oxygen absorbed on the electrode surface was reduced to protonated superoxide anion radical (HO2•). The HO2• was oxidized by SO4•− to produce molecular oxygen in both singlet and triplet states. Some of the singlet molecular oxygen (1O2) further combined through collision to be an energy‐rich precursor singlet molecular oxygen pair (1O2)2. A weak ECL was produced when 1O2 or (1O2)2 was converted to ground‐state molecular oxygen (3O2). When CPF was present, a stronger ECL was produced, which originated from two emitting species. The main emitting species was excited state CPF (CPF*), which was produced by accepting energy from (1O2)2. The other emitting species was excited singlet molecular oxygen pair [(1O2)2*], which originated from the chemical oxidation of CPF by SO4•− and dissolved oxygen. Based on the stronger ECL phenomenon, an ECL method for the determination of either S2O82− or CPF was proposed. The proposed ECL method has been applied to the determination of CPF in pharmaceutical preparations. Copyright © 2011 John Wiley & Sons, Ltd.
Laboratory Scale Test Minimizing Experimental Time and Effort for Pilot Scale Filtrations
Authors: Braun Frank , Hirthammer Markus , Krottenthaler Martin , Back Werner , Becker Thomas
Published: May 2011

Die Erforschung der Bierfiltration mit Zellulosefasern bedarf geeigneter Hilfsmittel, beispielsweise zur Vorbereitung von praxisnahen Versuchen. Anhand der Verläufe unterschiedlich angelegter Versuchsreihen im Pilotmaßstab wurde ein Labortest auf der Basis des Filtrierbarkeitstests nach Raible erarbeitet. Die Arbeit umfasst die Beschreibungen von Apparat, Prozedur und Methoden, die Ergebnisse zu bewerten. Der neue Test ist geeignet, den Versuchsaufwand im größeren Maßstab zu verringern. Vor allem in Bezug auf Variationen der Filterhilfsmittelzusammensetzung liefert er gute Ergebnisse.
Modularisation of Microstructured Separation Devices as a Method of Scale‐up using the Example of Distillation
Authors: Dercks Benedikt , Grünewald Marcus
Published: May 2011

Mikrostrukturierte Apparate werden seit geraumer Zeit als ein Ansatz zur Prozessintensivierung im Bereich der Reaktionstechnik diskutiert. Immer öfter wird in diesem Zusammenhang als Hemmnis für eine erfolgreiche Implementierung der Mikroverfahrenstechnik in Labor und Technik das Fehlen von Komponenten aus dem Bereich der Trenntechnik genannt. Dieser Beitrag stellt anhand von theoretischen Überlegungen am Beispiel der Destillation die Potenziale der Mikrotrenntechnik dar.
Glucose metabolism and blood pressure remain unchanged by addition of angiotensin receptor blocker in patients undergoing hemodialysis
Authors: Friedl A. , Mittermayer F. , Wolzt M. , Hörl W.H. , Haider D.G.
Published: May 2011

BACKGROUND

Angiotensin receptor blockers (ARBs) may exert effects on insulin sensitivity and blood pressure beyond those achieved by angiotensin‐converting enzyme inhibition (ACE‐I). The purpose of this study was to investigate whether this action is detectable in patients undergoing maintenance hemodialysis (HD) therapy.

METHODS

Twenty‐nine hypertensive HD patients, with (n = 17) or without diabetes (n = 12) received a daily add‐on therapy with 80 mg of telmisartan. Body mass index (BMI), fasting glucose, HbA1c, and blood pressure (BP) were recorded before and during 6 months of treatment.

RESULTS

HbA1c and blood glucose were higher in patients with diabetes at the beginning of the study and after 6 months. Fasting glucose tended to decrease over time in both groups of patients, but this change was not statistically significant. Likewise, HbA1c, BMI, and BP values remained unchanged.

CONCLUSIONS

Telmisartan does not improve glucose metabolism or lower blood pressure in patients receiving ACE‐I with or without diabetes undergoing maintenance HD. A preventive action on continuous deterioration of the clinical condition cannot be exluded.
Brachial artery blood flow measurement: A simple and noninvasive method to evaluate the need for arteriovenous fistula repair
Authors: Ogawa Tomonari , Matsumura Osamu , Matsuda Akihiko , Hasegawa Hajime , Mitarai Tetsuya
Published: May 2011

OBJECTIVE

The objective of this study was to evaluate the utility of brachial artery blood flow measurement in assessing the need for arteriovenous fistula (AVF) repair.

METHODS

In 236 hemodialysis patients, the relationships between the brachial artery blood flow measurement results and subsequent AVF repair and prognosis were investigated.

RESULTS

Mean brachial artery blood flow was significantly lower in patients requiring percutaneous transluminal angioplasty (PTA; treatment group, n = 161) than in patients followed without any treatment (no treatment group, n = 64; 250.3 mL/min versus 656.7 mL/min, p < 0.0001). When the relationship between the mean brachial artery blood flow and PTA requirement was analyzed using the ROC curve, the optimal cut‐off value with high sensitivity (true‐positive fraction [TPF]) and 1‐specificity (false‐positive fraction [FPF]) was 348.8 mL/min (area under the ROC curve = 0.814, FPF = 0.125, TPF = 0.87).

CONCLUSIONS

Decreased brachial artery blood flow of <350 mL/min is associated with the need for subsequent AVF repair, suggesting that this simple and noninvasive method could be used to evaluate vascular access (VA) patency and indication for AVF repair.
Tunneled hemodialysis catheters: What do nephrologists need to know?
Authors: Chan Micah R. , Salman Loay , Yevzlin Alexander S.
Published: May 2011

Even though many positive changes were ushered in by the KDOQI guidelines and the Fistula First Breakthrough Initiative, tunneled hemodialysis catheters remain an essential piece of the dialysis access puzzle. Their use is, however, attended by a multitude of complications and morbidity of which the general nephrologist must be aware. The purpose of this article is to review for the general nephrologist the infectious and non‐infectious problems that often complicate the use of hemodialysis catheters.
Hepatic Veno‐Occlusive Disease in a Kidney Transplant Patient: Case Report and Review of the Literature
Authors: Jalandhara Nishant , Thakor Pratapji , Goswami Monica , Zhang Rubin
Published: May 2011

Veno‐occlusive disease (VOD) of the liver is an extremely rare complication of azathioprine (AZT) use in patients with kidney transplants (KTs). Although VOD is frequently seen in bone marrow transplant patients, so far only 24 cases have been reported in KT patients. Our case adds to the available data on the disease, and we also reviewed the published data on this entity to establish the characteristics of VOD in the setting of KT. Our case highlights the importance of this potentially life‐threatening complication and provides an overview of VOD in KT patients.
Modulation of neurite outgrowth by activation of calcium‐permeable kainate receptors expressed by rat nociceptive‐like dorsal root ganglion neurons
Authors: Joseph Donald J. , Williams Damian J. , MacDermott Amy B.
Published: May 2011

Neurite outgrowth is a fundamental step in establishing proper neuronal connections in the developing central nervous system. Dynamic control of outgrowth has been attributed to changes in growth cone Ca2+ levels in response to extracellular cues. Here we have investigated a possible role for Ca2+ permeable kainate (KA) receptors in regulating neurite outgrowth of nociceptive‐like dorsal root ganglion (DRG) neurons. To identify KA receptor subunits likely to be involved, we used quantitative RT‐PCR on acutely dissociated DRG and dorsal horn neurons. DRG neurons expressed more GluK1, particularly the GluK1b spice variant, than dorsal horn neurons. Conversely, dorsal horn neurons expressed more GluK2, particularly GluK2a, than DRG neurons. Further, an RNA editing assay indicated that the majority of GluK1 and GluK2 mRNA transcripts in DRG were unedited. Imaging Ca2+ transients following application of a KA receptor agonist to DRG and dorsal horn co‐cultures revealed increases in intracellular Ca2+ in the growth cones of DRG neurons. In the majority of cases, this increase in Ca2+ was partly or completely blocked by Joro spider toxin (JSTX), an antagonist for Ca2+‐permeable AMPA and KA receptors. Treatment of DRG/dorsal horn co‐cultures with KA for 18 hours suppressed neurite outgrowth while application of the rapidly desensitizing KA receptor agonist SYM 2081, the competitive AMPA/KA receptor antagonist, CNQX, and JSTX or philanthotoxin enhanced neurite outgrowth and prevented KA effects on neurite outgrowth. Thus, Ca2+ entry through KA receptors at the growth cone of DRG neurons may be an important regulator of neurite outgrowth. © 2011 Wiley Periodicals, Inc. Develop Neurobiol 71: 818–835, 2011
Neurotransmitter phenotype plasticity: An unexpected mechanism in the toolbox of network activity homeostasis
Authors: Demarque Michaël , Spitzer Nicholas C.
Published: May 2011

The transmitter phenotype of a neuron has long been thought to be stable for the lifespan. Much as eyes have one color and do not change it over time, neurons have been thought to have one neurotransmitter and retain it for their lifetime. Both principles, exclusivity and stability, are challenged by recent data. More and more neurons in different regions of the brain appear to coexpress two or more neurotransmitters. Moreover, the profile of neurotransmitter expression of a given neuron has been shown to change over time, both during development and in response to changes in activity. The present review summarizes recent studies of this neurotransmitter phenotype plasticity (NPP). Homeostatic mechanisms of plasticity are aimed at maintaining the system within a functional range. They appear to be critical for optimal network operations and have been thought to operate largely by regulating intrinsic excitability, synapse number and synaptic strength. NPP provides a new and unexpected level of regulation of network homeostasis. We propose that it provides the basis for NT coexpression and discuss emerging issues and new questions for further studies in coming years. © 2011 Wiley Periodicals, Inc. Develop Neurobiol 72: 22–32, 2012
Timescales of hydrolimnological change in floodplain lakes of the Peace‐Athabasca Delta, northern Alberta, Canada
Authors: Wiklund Johan A. , Hall Roland I. , Wolfe Brent B.
Published: May 2011

Repeated measurements over 3 years (2003–2005) were made on a series of lakes along a hydrological gradient in the Peace‐Athabasca Delta (PAD), Canada, to characterize the role of river flooding on limnological conditions of northern floodplain lakes and to identify the patterns and timescales of limnological change after flooding. River floodwaters elevate concentrations of suspended sediment, total phosphorus (TP), SO4 and dissolved silica (DSi) and reduce concentrations of total Kjeldahl nitrogen (TKN), dissolved organic carbon (DOC) and most ions, which leads to increased limnological homogeneity among lakes. After flooding, limnological changes occur at two distinct timescales. In the weeks to months after flooding, water clarity increases as suspended sediments and TP settle out of the water column, but concentrations of DOC, SO4, TKN and ions do not change appreciably. However, in the absence of flooding for many years to decades, evaporative concentration leads to an increase in most nutrients, DOC and ions. Contrary to a prevailing paradigm, these results suggest that regular flooding is not required to maintain high nutrient concentrations. In light of anticipated declines in river discharge, we predict that limnological conditions in the southern Athabasca sector will become increasingly less dominated by the short‐term effects of flooding, and resemble nutrient‐ and solute‐rich lakes in the northern Peace sector that are infrequently flooded. Copyright © 2011 John Wiley & Sons, Ltd.
Quantitative gel electrophoresis: New records in precision by elaborated staining and detection protocols
Authors: Deng Xi , Schröder Simone , Redweik Sabine , Wätzig Hermann
Published: May 2011

Gel electrophoresis (GE) is a very common analytical technique for proteome research and protein analysis. Despite being developed decades ago, there is still a considerable need to improve its precision. Using the fluorescence of Colloidal Coomassie Blue ‐stained proteins in near‐infrared (NIR), the major error source caused by the unpredictable background staining is strongly reduced. This result was generalized for various types of detectors. Since GE is a multi‐step procedure, standardization of every single step is required. After detailed analysis of all steps, the staining and destaining were identified as the major source of the remaining variation. By employing standardized protocols, pooled percent relative standard deviations of 1.2–3.1% for band intensities were achieved for one‐dimensional separations in repetitive experiments. The analysis of variance suggests that the same batch of staining solution should be used for gels of one experimental series to minimize day‐to‐day variation and to obtain high precision.
Haplotyping of putative microRNA‐binding sites in the SNAP‐25 gene
Authors: Kovacs‐Nagy Reka , Sarkozy Peter , Hu Jimmy , Guttman Andras , Sasvari‐Szekely Maria , Ronai Zsolt
Published: May 2011

Synaptosomal‐associated protein 25 (SNAP‐25) plays a crucial role in exocitosis. Single nucleotide polymorphisms (rs3746544 and rs1051312) in the 3′ un‐translated region of the SNAP‐25 gene have been described to be in association with attention‐deficit hyperactivity disorder. As the disease affects millions of children world‐wide, understanding the genetic background of attention‐deficit hyperactivity disorder is of crucial importance. Efficient and reliable PCR‐RFLP protocols were elaborated for the genotyping of the rs3746544 and rs1051312 SNPs employing a high‐throughput capillary electrophoresis method for fragment analysis. A novel real‐time PCR‐based technique was used applying sequence specific TaqMan probes to haplotype the two SNPs, and the G–C haplotype could not be detected in a large Caucasian population (N=1376). These findings have been confirmed by molecular biology tools as well as by the PHASE Bayesian computational approach. In silico analyses have suggested that the two SNPs might alter microRNA binding and thus have an effect on SNAP‐25 production. We have demonstrated that this biological information can be revealed only by direct haplotype analysis emphasizing the importance of our novel molecular haplotye analysis protocol. Results of the study of the two SNPs might shed light on the association of SNAP‐25 variants and pathological phenotypes at the molecular level.
Proteomic biomarker discovery: It's more than just mass spectrometry
Authors: Blonder Josip , Issaq Haleem J. , Veenstra Timothy D.
Published: May 2011

The previous decade witnessed an enormous number of studies with the singular goal of identifying protein biomarkers for diseases such as cancer. A large majority of these studies have focused on comparative studies of serum or plasma obtained from disease‐affected and control patients. In these studies, proteins identified in the samples using MS were compared with the hope that differences between samples would reveal useful biomarkers. Unfortunately, finding clinically relevant biomarkers has often been elusive and frustrating. As with most research efforts, both successes and failures, much has been learned about what strategies work and which do not. Part of the problem can be attributed to underestimating the effort required to discover novel biomarkers and depending too heavily on MS analysis of peripheral blood samples. Fortunately, the future for biomarker discovery still appears bright. MS technology continues to increase in sensitivity, throughput, and accuracy while novel types of samples and clever experimental designs coupled with innovative bioinformatics will make this vision of routine biomarker discovery a reality. To achieve ultimate success is going to require concomitant application of a number of different technologies, all providing the information necessary for discovering and validating clinically useful biomarkers.