Effects of moisture and temperature on carbon and nitrogen mineralization in mine tailings mixed with sewage sludge

Digested sewage sludge mixed with copper mine tailings was incubated for 3 mo at 16 combinations of temperature (-1, 5, 10, and 15 degrees C) and soil moisture content (2, 8, 14, and 24% by weight). Carbon dioxide evolution and net N mineralization were measured at increasing time intervals. A two compartment first-order kinetic model (refractory and labile C) was fitted to the time series of measured CO2 fluxes using nonlinear regression analysis. The dependencies of the rate constants on moisture and temperature could be well described by log-linear functions. The estimated Q10 value (the factor by which the rate is increased as temperature is increased 10 degrees C) was 2.55. Within the range of temperature and moisture considered here, which correspond to conditions occurring naturally in Sweden, CO2 evolution was more strongly controlled by moisture than by temperature. Less mineral N accumulated during the experiment at the lowest moisture or temperature. However, the dependency of net N mineralization on moisture and temperature in the remaining treatments was less clear than for C evolution, presumably due to denitrification at the higher temperatures and moisture contents. Nitrate was formed after around 2 wk but only at 10 and 15 degrees C.     

Biomonitoring in the protected areas of the Czech Republic

The purpose of the biomonitoring project in the Nature Conservancy in the Czech Republic is to obtain information on long-term development of some selected living components of ecosystems in protected areas. A survey of methods was conducted to select the monitoring areas as well as to study birds, epigean, vegetation and water communities (a minimal programme). A system for the monitoring areas and data storage and processing (to gather a body of evidence) was established. Simultaneously, close linkage with abiotic factor monitoring is planned. The project has been carried out by the Czech Institute for Nature Conservation.     

Sub-lethal hydrops as a manifestation of dehydrated hereditary stomatocytosis in two consecutive pregnancies

Dehydrated hereditary stomatocytosis (DHS) is a rare congenital hemolytic anemia mapping to 16q23–q24. We showed recently that it is part of a pleiotropic syndrome likely to display pseudohyperkalemia and/or different forms of fetal and placental fluid collections. Here, we report a woman with DHS. She had two consecutive pregnancies associated with severe fetal hydrops. Hydrops would probably have been lethal in the absence of appropriate removal of ascites and excess amniotic fluid. In utero exchange transfusion, performed once, was useless, because anemia was not pronounced enough to be the cause of the hydrops. In both newborns, ascites resolved within a week following birth and never recurred. The association of hydrops and hemolytic anemia suggests the possibility of DHS. Symptomatic treatment of the hydrops assists survival until spontaneous resorption occurs. Copyright © 2003 John Wiley & Sons, Ltd.     

On multiple objective optimization in aquatic ecosystems

Optimal control criteria and hierarchical dynamic control have been designed for a class of structural nonlinear predator-prey models (nutrient-herbivore-predator). The optimal open-loop control of the class of models considered is described. The optimal control design is realized using the hierarchical coordination strategies which are mathematically based on the gradient approach for the interaction prediction principle.     

Designing a conservation reserve network with minimal fragmentation: A linear integer programming approach

In the biological conservation literature, the optimum reserve site selection problem has often been addressed by using the prototype set covering and maximal covering formulations, assuming that representation of species is the only criterion in site selection. This approach usually results in a small but highly fragmented reserve, which is not useful for practical conservation planning. To improve the chances of species' persistence, it may be desirable to reduce habitat fragmentation. This paper presents a linear integer programming formulation to minimize spatial gaps between selected sites in a reserve network, which is applied to a data set on breeding birds. The authors express their willingness to share the database used in this study. Those readers who wish to have access to the data may contact Robert A. Briers at r.briers@napier.ac.uk.     

Effect of the Shellfish Proteinase K Digestion Method on Norovirus Capsid Integrity

Norovirus outbreaks are associated with the consumption of contaminated shellfish, and so efficient methods to recover and detect infectious norovirus in shellfish are important. The Proteinase K digestion method used to recover norovirus from shellfish, as described in the ISO 15216, would be a good candidate but its impact on the virus capsid integrity and thus infectivity was never examined. The aim of this study was to assess the impact of the Proteinase K digestion method, and of the heat treatment component of the method alone, on norovirus (genogroups I and II) and MS2 bacteriophage capsid integrity. A slightly modified version of the ISO method was used. RT-qPCR was used for virus detection following digestion of accessible viral RNA using RNases. MS2 phage infectivity was measured using a plaque assay. The effect of shellfish digestive glands (DG) on recovery was evaluated. In the presence of shellfish DG, a reduction in MS2 phage infectivity of about 1 log₁₀ was observed after the Proteinase K digestion method and after heat treatment component alone. For norovirus GII and MS2 phage, there was no significant loss of genome following the Proteinase K digestion method but there was a significant 0.24 log₁₀ loss of norovirus GI. In the absence of shellfish DG, the reduction in MS2 phage infectivity was about 2 log₁₀, with the addition of RNases resulting in a significant loss of genome for all tested viruses following complete Proteinase K digestion method and the heat treatment alone. While some protective effect from the shellfish DG on viruses was observed, the impact on capsid integrity and infectivity suggests that this method, while suitable for norovirus genome detection, may not completely preserve virus infectivity.     

Modeling and study of magnetorheological fluid impact base frequency enhancement for a micro-piezoelectric energy generator

ABSTRACT

This paper proposes a new concept using magnetorheological fluids (MRF) as an impacting object or stopper for frequency tuning and power enhancement for a vibrating piezoelectric bimorph cantilever beam. MRF is a smart fluid that changes from a liquid state into a semi-solid state within milliseconds when a magnetic field is applied. The paper presented analytical, finite element method (FEM) and experimental results. The analytical results showed a frequency increase of 4% when the vibrating cantilever beam impacted on an activated MRF at 0.3 T magnetic field application compared to the free vibrating beam without the MRF stopper. The FEM simulation results, on the other hand, showed a 3.8% increase in frequency when the vibrating cantilever beam impacted on an activated MRF at 0.3 T magnetic field application compared to the free vibrating beam without MRF stopper. The frequency increased by 6.5% at 0.3 T magnetic field application in the experimental study. The experimental results validated the frequency enhancement of analytical results and FEM simulated results. The analytical power output results, when the vibrating cantilever beam impacted on the activated impact MRF at 0.3 T gave a maximum power output of 410ript>rc="/na101/home/literatum/publisher/tandf/journals/content/ljge20/2020/ljge20.v017.i09/15435075.2020.1763356/20200601/images/ljge_a_1763356_ilm0001.gif" alt="" />ript>rc="//:0" alt="" class="mml-formula" data-formula-source="{"type" : "image", "src" : "/na101/home/literatum/publisher/tandf/journals/content/ljge20/2020/ljge20.v017.i09/15435075.2020.1763356/20200601/images/ljge_a_1763356_ilm0001.gif"}" />rc="//:0" alt="" data-formula-source="{"type" : "mathjax"}" />$\mu W$and a load resistance of 37ript>rc="/na101/home/literatum/publisher/tandf/journals/content/ljge20/2020/ljge20.v017.i09/15435075.2020.1763356/20200601/images/ljge_a_1763356_ilm0002.gif" alt="" />ript>rc="//:0" alt="" class="mml-formula" data-formula-source="{"type" : "image", "src" : "/na101/home/literatum/publisher/tandf/journals/content/ljge20/2020/ljge20.v017.i09/15435075.2020.1763356/20200601/images/ljge_a_1763356_ilm0002.gif"}" />rc="//:0" alt="" data-formula-source="{"type" : "mathjax"}" /> The FEM simulation results on the hand showed a maximum power output of 405ript>rc="/na101/home/literatum/publisher/tandf/journals/content/ljge20/2020/ljge20.v017.i09/15435075.2020.1763356/20200601/images/ljge_a_1763356_ilm0003.gif" alt="" />ript>rc="//:0" alt="" class="mml-formula" data-formula-source="{"type" : "image", "src" : "/na101/home/literatum/publisher/tandf/journals/content/ljge20/2020/ljge20.v017.i09/15435075.2020.1763356/20200601/images/ljge_a_1763356_ilm0003.gif"}" />rc="//:0" alt="" data-formula-source="{"type" : "mathjax"}" />$\mu W$and a load resistance of 37.2ript>rc="/na101/home/literatum/publisher/tandf/journals/content/ljge20/2020/ljge20.v017.i09/15435075.2020.1763356/20200601/images/ljge_a_1763356_ilm0004.gif" alt="" />ript>rc="//:0" alt="" class="mml-formula" data-formula-source="{"type" : "image", "src" : "/na101/home/literatum/publisher/tandf/journals/content/ljge20/2020/ljge20.v017.i09/15435075.2020.1763356/20200601/images/ljge_a_1763356_ilm0004.gif"}" />rc="//:0" alt="" data-formula-source="{"type" : "mathjax"}" /> when the vibrating cantilever impacted the activated MRF at 0.3 T magnetic field application. The experimental results demonstrated a power output of 403ript>rc="/na101/home/literatum/publisher/tandf/journals/content/ljge20/2020/ljge20.v017.i09/15435075.2020.1763356/20200601/images/ljge_a_1763356_ilm0005.gif" alt="" />ript>rc="//:0" alt="" class="mml-formula" data-formula-source="{"type" : "image", "src" : "/na101/home/literatum/publisher/tandf/journals/content/ljge20/2020/ljge20.v017.i09/15435075.2020.1763356/20200601/images/ljge_a_1763356_ilm0005.gif"}" />rc="//:0" alt="" data-formula-source="{"type" : "mathjax"}" />$\mu W$ at 0.3 T and a load resistance of 36.7ript>rc="/na101/home/literatum/publisher/tandf/journals/content/ljge20/2020/ljge20.v017.i09/15435075.2020.1763356/20200601/images/ljge_a_1763356_ilm0006.gif" alt="" />ript>rc="//:0" alt="" class="mml-formula" data-formula-source="{"type" : "image", "src" : "/na101/home/literatum/publisher/tandf/journals/content/ljge20/2020/ljge20.v017.i09/15435075.2020.1763356/20200601/images/ljge_a_1763356_ilm0006.gif"}" />rc="//:0" alt="" data-formula-source="{"type" : "mathjax"}" />.     

Automatic model calibration applying global optimization techniques

This paper summarizes a study aimed at the application of global optimization techniques for the purpose of quantitative characterization of the Wolfville formation located in Nova Scotia, Canada. Aquifer parameters (transmissivity, storativity, areal recharge and boundary flux) are calibrated in order to yield the best possible match with the available field observations. The calibration is accomplished using a global approach to the inverse procedure in “black box” systems optimization which makes possible the simultaneous fitting of several tens of parameters. This study indicates that, even for a limited number of optimized parameters, a global search procedure should be considered. Numerical results are presented and discussed to show the validity of the approach.