Some properties of the point processes generated by integral density modulation of renewal processes

Integral density modulation of point processes is defined, and the properties of the modulated point processes are described. When a homogeneous renewal process is modulated by a step random signal, the mathematical expressions are derived of the probability density functions of the sums of r-successive inter point intervals, the intensity functions and the first order correlation coefficient of intervals. These quantities are calculated and illustrated for several parameter values. Modulated point sequences are generated by computer simulation method. The interval histograms and the serial correlation coefficients of counts and of intervals of the sequences are obtained. The results are compared with the theoretical results on the point processes modulated by the step random signal.Abbreviations IDM Integral density modulation - SRS Step random signal - PP Point process - PS Point sequence - PDF Probability density function - CPDF Conditional probability density function - JCPDF Joint conditional probability density function - SED Special Earlangian distribution - SCC Serial correlation coefficients - SIC Serial intensity coefficients     

Utilization of the cyanobacteria Anabaena sp. CH1 in biological carbon dioxide mitigation processes

Before switching totally to alternative fuel stage, CO₂ mitigation process has considered a transitional strategy for combustion of fossil fuels inevitably. In comparison to other CO₂ mitigation options, such as oceanic or geologic injection, the biological photosynthetic process would present a far superior and sustainable solution under both environmental and social considerations. The utilization of the cyanobacteria Anabaena sp. CH1 in carbon dioxide mitigation processes is analyzed in our research. It was found that an original developed photobioreactor with internal light source exhibits high light utilization. Anabaena sp. CH1 demonstrates excellent CO₂ tolerance even at 15% CO₂ level. This enables flue gas from power plant to be directly introduced to Anabaena sp. CH1 culture. Double light intensity and increased 47% CO₂ bubble retention time could enhance CO₂ removal efficiencies by 79% and 67%, respectively. A maximum CO₂ fixation rate of 1.01 g CO₂ L⁻¹ day⁻¹ was measured experimentally.     

Energy costs of carbon dioxide concentrating mechanisms in aquatic organisms

Minimum energy (as photon) costs are predicted for core reactions of photosynthesis, for photorespiratory metabolism in algae lacking CO₂ concentrating mechanisms (CCMs) and for various types of CCMs; in algae, with CCMs; allowance was made for leakage of CO₂ from the internal pool. These predicted values are just compatible with the minimum measured photon costs of photosynthesis in microalgae and macroalgae lacking or expressing CCMs. More energy-expensive photorespiration, for example for organisms using Rubiscos with lower CO₂–O₂ selectivity coefficients, would be less readily accommodated within the lowest measured photon costs of photosynthesis by algae lacking CCMs. The same applies to the cases of CCMs with higher energy costs of active transport of protons or inorganic carbon species, or greater allowance for significant leakage from the accumulated intracellular pool of CO₂. High energetic efficiency can involve a higher concentration of catalyst to achieve a given rate of reaction, adding to the resource costs of growth. There are no obvious mechanistic interpretations of the occurrence of CCMs algae adapted to low light and low temperatures using the rationales adopted for the occurrence of C₄ photosynthesis in terrestrial flowering plants. There is an exception for cyanobacteria with low-selectivity Form IA or IB Rubiscos, and those dinoflagellates with low-selectivity Form II Rubiscos, for which very few natural environments have high enough CO₂:O₂ ratios to allow photosynthesis in the absence of CCMs.     

On two species of Diptera described by I. A. Portschinsky in 1876

In 1876 I.A. Portschinsky described two species of Diptera: Urellia muscipora Portschinsky (Tephritidae) and Phlebotomus grimmi Portschinsky (Psychodidae–Phlebotominae). The former name is a senior synonym of Goniurellia tridens (Hendel, 1910), but it was not used as a valid name since 1876 and should be rejected according to Articles 23.9.1.1 and 23.9.1.2 of the ICZN. The name Phlebotomus grimmi was in use in 1926–1984 as a valid name and as a senior synonym of Ph. sergenti Parrot, 1917 or Ph. caucasicus Marzinovsky, 1917. It is necessary to appeal to the International Commission on Zoological Nomenclature to establish the status of Phlebotomus grimmi Portschinsky, 1876.     

Analysis of the sensing and transducing processes implicated in the stomatal responses to carbon dioxide in Commelina communis L.

It has been previously debated whether CO₂ would depolarize the guard cell plasma membrane through malate‐mediated activation of the anion channel. Moreover, it has been assessed that the CO₂ signal would be transduced via cytosolic free Ca^{2 +} . In the present study, the CO₂ sensing and transducing processes were reinvestigated in Commelina communis (L.) mainly by studying how L ‐(–)‐malic acid and Ca^{2 +} flux modulators affected different CO₂ stomatal responses. L ‐(–)‐malic acid (1 m M ) inhibited by about 50% both CO₂‐induced stomatal closing and CO₂‐triggered inhibition of the stomatal opening response to the auxin indolyl‐3‐butyric acid. Stomatal closing in response to atmospheric CO₂ was strongly inhibited by the 1,4 dihydropyridines SDZ‐202 791 R(–) (SDZ (–)) and nifedipine, and this inhibition was attenuated by the 1,4 dihydropyridines SDZ‐202 791 S( + ) and S‐(–)‐BAY K8644. Suboptimal concentrations of the slow anion channel blockers 5‐nitro‐2,3‐phenylpropyllamine benzoic acid and anthracene‐9‐carboxylic acid increased the 50% inhibition of the CO₂ closing response by the Ca^{2 +} flux modulators SDZ (–) and 1,2‐bis(o‐aminophenoxy)ethane‐N,N,N ′ N ′ ‐tetraacetic acid in a stronger manner than an additive one. Together, these results support the view that CO₂ is sensed through reducing proton extrusion. Moreover, they might suggest that the CO₂ signal is transduced through Ca^{2 +} signalling arising from depolarization‐mediated activation of a putative plasma membrane voltage‐gated L‐type Ca^{2 +} channel and for which the plasma membrane slow anion channel is a potential target.     

On the solubility of disodium p-nitrophenyl phosphate in supercritical carbon dioxide

Summary The title compound is shown to be insoluble in supercritical carbon dioxide, and an earlier report of its enzymatic hydrolysis in supercritical carbon dioxide is shown to be erroneous.