Investigating periphyton biofilm response to changing phosphorus concentrations in UK rivers using within-river flumes

The excessive growth of benthic algal biofilms in UK rivers is a widespread problem, resulting in loss of plant communities and wider ecological damage. Elevated nutrient concentrations (particularly phosphorus) are often implicated, as P is usually considered the limiting nutrient in most rivers. Phosphorus loadings to rivers in the UK have rapidly decreased in the last decade,due to improvements in sewage treatment and changes to agricultural practises. However, in many cases, these improvements in water quality have not resulted in a reduction in nuisance algal growth. It is therefore vital that catchment managers know what phosphorus concentrations need to be achieved, in order to meet the UK’s obligations to attain good ecological status, under the EU’s Water Framework Directive. This study has developed a novel methodology, using within river mesocosms, which allows P concentrations of river water to be either increased or decreased, and the effect on biofilm accrual rate is quantified. These experiments identify the phosphorus concentrations at which algae becomes P-limited, which can be used to determine knowledge-based P targets for rivers. The ability to reduce P concentrations in river water enables algae–nutrient limitation to be studied in nutrient-enriched rivers for the first time

Loading fluorescent Ca²⁺ indicators into living cells

Small-molecule fluorescent Ca2+ reporters are the most widely used tools in the field of Ca2+ signaling. The excellent spatial and temporal resolution afforded by fluorescent reporters has driven the understanding of Ca2+ as a messenger in many different cell types. In many situations, the cellular loading and monitoring of fluorescent Ca2+ indicators is quite trivial. However, there are numerous pitfalls that require consideration to ensure that optimal data are recorded. Fluorescent Ca2+ indicators have carboxylic acid groups for binding of Ca2+. Because these “free-acid” forms of the indicators are hydrophilic they cannot readily cross cell membranes and need to be introduced into cells using techniques such as microinjection, pinocytosis, or diffusion from a patch pipette. However, the most convenient and widely used method for loading indicators into cells is as hydrophobic compounds in which the carboxylic acid groups are esterified (commonly as acetoxymethyl [AM] or acetate esters). The ester versions of the indicators permeate the plasma membrane. The Ca2+-sensitive, free-acid form of the indicator is liberated following hydrolysis of the ester groups by intracellular esterases

Plasma N-Terminal Pro-Brain Natriuretic Peptide as Prognostic Marker in Fatal Cardial Decompensation with Sunitinib Malate Therapy

A 74-year-old man with metastatic renal cell carcinoma and a history of cardiac failure was treated with sunitinib malate. MUGA echocardiography could not detect a relevant change in the ejection fraction although the clinical situation of the patient worsened dramatically. The only parameter to hint at the deteriorated cardiac function was plasma N-terminal pro-brain natriuretic peptide (BNP). Finally, the patient died after only one cycle of sunitinib treatment. We propose to prospectively include BNP for the early detection of cardiovascular decompensation in high-risk patients. Future studies concerning the relevance of BNP in drug-related cardiotoxicity are urgently needed. Copyright (C) 2010 S. Karger AG, Base

Mixed Pricing in Online Marketplaces

A rich theory literature predicts mixed strategies in posted prices due to standard price discrimination, search frictions, and various other rationales. While typically interpreted as implying occasional sales or price dispersion, online marketplaces enable a firm to truly use randomization as a tool in pricing, and so such behavior should be expected to arise in online settings. We investigate a case of mixed pricing across a large subset of products on a major e-commerce website. We first test for randomizing behavior, and then construct a model of price discrimination that would generate randomization as optimal behavior. We estimate the model and use it to assess pricing effects of a proposed merger in the industry

Economic, Environmental and International Trade Effects of the EU Directive on Energy Tax Harmonization

In October 2003, the European Union introduced a Directive which widens the scope of the EU's minimum taxation system from mineral oils to all energy products including coal, natural gas and electricity. It aims at reducing distortions that currently exist between Member States as well as between energy products. In addition, it increases previous minimum tax rates and thus the incentive to use energy more efficiently. The Directive will lead to changes in the energy tax schemes in a number of countries, in particular some southern Member Countries (Greece, Spain, Portugal) and most of the Eastern European EU candidate countries. In this paper, we analyze the effects of the EU energy tax harmonization with GTAP-E, a computable general equilibrium model. Particular focus is placed on the Eastern European countries which became new members of the EU in May 2004. We investigate the effects of the tax harmonization on overall economic growth and sectoral development. Special attention is paid to international trade in order to analyze if competitiveness concerns which have been forwarded in the context of energy taxation are valid. Furthermore, the effect on energy consumption and emissions and thus the contribution to the EU's climate change targets is analyzed.

WeLL – Unique Linked Employer-Employee Data on Further Training in Germany

This paper explains the main features of an innovative linked employer-employee data set with a particular focus on continuous training in Germany, calledWeLL. The data set comprises establishment data that can be linked to longitudinal information on the associated employees. The employer survey and the first wave of the employee survey were conducted in 2007. Both surveys focus on the collection of training information together with a variety of employee and employer background characteristics. In addition, it is possible to link these data with other survey and administrative data for a large number of respondents.Employee training, establishment data, linked employer-employee data