REDD DEWATERING EFFECTS ON HATCHING AND LARVAL SURVIVAL OF THE ROBUST REDHORSE

Riverine habitats have been altered and fragmented from hydroelectric dams and change spatially and temporally with hydropower flow releases. Hydropeaking flow regimes for electrical power production inundate areas that create temporary suitable habitat for fish that may be rapidly drained. Robust redhorse Moxostoma robustum, an imperiled, rare fish species, uses such temporary habitats to spawn, but when power generation ceases, these areas are dewatered until the next pulse of water is released. We experimentally simulated the effects of dewatering periods on the survival of robust redhorse eggs and larvae in the laboratory. Robust redhorse eggs were placed in gravel in eyeing‐hatching jars (three jars per treatment) and subjected to one of four dewatering periods (6, 12, 24 and 48 h), followed by 12 h of inundation for each treatment, and a control treatment was never dewatered. Egg desiccation was observed in some eggs in the 24‐ and 48‐h treatments after one dewatering period. For all treatments except the control, the subsequent dewatering period after eggs hatched was lethal. Larval emergence for the control treatment was observed on day 5 post‐hatching and continued until the end of the experiment (day 21). Larval survival was significantly different between the control and all dewatering treatments for individuals in the gravel. These findings support the need for hydropower facilities to set minimum flows to maintain inundation of spawning areas for robust redhorse and other species to reduce dewatering mortality. Copyright © 2012 John Wiley & Sons, Ltd.     

Characterisation of different typical Italian breads by means of traditional,spectroscopic and image analyses

In this paper a complete characterisation of four typical durum wheat breads produced in Italy was performed, from the starting semolinas to the final product, also considering the intermediate dough. An evaluation of the quality of durum wheat re-milled semolinas was carried out by means of routine investigations, together with nuclear magnetic resonance (NMR) and isotope ratio mass spectrometry (IRMS) analyses, that were also applied to dough ready for baking and bread to monitor the variations that occur during processing. The experimental data obtained from routine and spectroscopic determinations were investigated using multivariate statistical analysis to evaluate the possibility of differentiating flours, doughs and breads according to their geographical origin. Computerised image analysis was applied to quantify the crumb grain features of different bread types, and to try to characterise each bread type through a set of crumb morphological and colour parameters.     

Crosstalk investigation of laser-diode pairs

The crosstalk between the lasers of different laser-diode pairs has been investigated experimentally in the frequency domain. The mutual crosstalk of two lasers diodes monolithically integrated on a single transmitter chip and separated by 100 μm was measured to be about -50 dB up to a modulation frequency of 100 MHz. At higher frequencies, it rises linearly with the frequency to -40 dB at 1 GHz. Measurements and calculations indicate that the origin of this crosstalk is the leakage current in the chip and inductive coupling of the bond wires. With these crosstalk values, digital data transmission at high bit rates is possible without significantly reducing the receiver sensitivity     

Distribution of SIV infection in the gastrointestinal tract of rhesus macaques at early and terminal stages of AIDS

Intestinal tissues from SIV-infected rhesus macaques with subclinical as well as with terminal SIV disease were evaluated for SIV infection. SIV-infected mononuclear cells were detected throughout the gastrointestinal tract in all animals. In early infection, SIV-infected cells were diffusely distributed in lymphoid tissue and lamina propria, whereas in late stages of the disease, the viral infection was more severe and widely disseminated. Lymphoid cells of the lamina propria and gut-associated lymphoid tissue were the primary targets of SIV.     

Numerical calculation of eigenvalues of integral operators for plane elastostatic boundary value problems

For numerical treatment integral equations are discretized and replaced by systems of algebraic equations. The condition properties of these systems depend on the eigenvalues and eigenvectors of the corresponding coefficient matrices. In this paper the eigenvalues of four integral operators for plane elastostatic boundary value problems are calculated numerically and checked against exact data. The results of the evaluations are represented in condensed form as condition numbers, which can be used to estimate the truncation error. The decay behaviour of the error of the numerically calculated eigenvalues permits the precision to be improved by application of Richardson extrapolation.     

Condition of boundary integral equations in which the sought-for function and the given right-hand side are defined on different domains; round-off errors in the numerical solutions

Boundary integral equations in which the sought-for function and the given right-hand side are defined on different curves have the great advantage of regularity. Descretization of them, however, yields ill-conditioned systems of algebraic equations, i. e., systems susceptible to round-off errors. In this paper the round-off error is determined as a function of the number of nodes and as a function of the distance between the domains of definition of the solution and of the boundary values. The results corroborate and specify a theoretically deduced rule Heise (1978a) on how to carry out the numerical evaluation without spoiling the solution by round-off errors. An extensive survey of the paper is given in Sect. 2.