[Intraspecies variation of reproductive strategies in river perch (Perca fluviatilis)].

The variation of reproductive strategies in different populations of river perch and intrapopulation groups differing in the rate of growth have been analyzed. Using a bioenergetic approach, the origin and differences between these groups have been studied. It was shown that bioenergetic mechanisms of regulation of the sizes and weight of the eggs lead to formation of the strategy of forced reproduction in the slow-growing group of perch, unlike the reproductive strategy of the fast-growing group of perch characterized by a later reaching of sexual maturity at a greater relative weight of gonads and spawning of larger eggs, which provides for a longer lifespan of larvae. The great number of age groups in the spawning part of this group compensates for a decrease in reproduction in years with unfavorable conditions.

Relationship between turbidity and total suspended solids concentration within a combined sewer system.

This article confirms the existence of a strong linear relationship between turbidity and total suspended solids (TSS) concentration. However, the slope of this relation varies between dry and wet weather conditions, as well as between sites. The effect of this variability on estimating the instantaneous wet weather TSS concentration is assessed on the basis of the size of the calibration dataset used to establish the turbidity - TSS relationship. Results obtained indicate limited variability both between sites and during dry weather, along with a significant inter-event variability. Moreover, turbidity allows an evaluation of TSS concentrations with an acceptable level of accuracy for a reasonable rainfall event sampling campaign effort.

[Intraspecific variability of life strategies in boreal fishes inhabiting wide ranges].

Variability of the population structure, parameters of growth, and reproduction were analyzed in two freshwater (Siberian sturgeon and bream) and two marine (cod and flounder) widespread boreal fish species. These species have similar spectrums of adaptive life strategies including (a) the strategy of populations inhabiting zones of the species optimum, (b) the strategy of populations inhabiting the northern peripheral zones of low temperature and unstable food supply, (c) the strategy of populations inhabiting the southern peripheral zones, and (d) the strategy of dwarf forms. These spectrums of life strategies are apparently determined by (1) a high degree of intraspecific variability of the protein synthesis scale within extensive ranges of the species under study, (2) labile mechanisms regulating the plastic and generative metabolism ratio during ontogeny which are determined not only by thermal conditions but also by the level of food supply and its fluctuations, and (3) the mechanism regulating the size and weight of eggs.

[Anomalies in the development and functioning of the reproductive system in Siberian sturgeon, Acipenser baerii Brandt (Acipenseridae), from the Yenisei River].

Based upon long-term studies, the alterations in the development and functioning of the reproductive system in the Yenisei River Siberian sturgeon are analyzed. Primary attention is paid to the malfunctions of gametogenesis during trophoplasmatic growth of the oocytes. Some anomalies were revealed for the first time in the studied population. However, these anomalies are typical for other populations of this species. These anomalies are not species-specific and may be found in other representatives of the family Acipenseridae.

Reproducibility and uncertainty of wastewater turbidity measurements.

Turbidity monitoring is a valuable tool for operating sewer systems, but it is often considered as a somewhat tricky parameter for assessing water quality, because measured values depend on the model of sensor, and even on the operator. This paper details the main components of the uncertainty in turbidity measurements with a special focus on reproducibility, and provides guidelines for improving the reproducibility of measurements in wastewater relying on proper calibration procedures. Calibration appears to be the main source of uncertainties, and proper procedures must account for uncertainties in standard solutions as well as non linearity of the calibration curve. With such procedures, uncertainty and reproducibility of field measurement can be kept lower than 5% or 25 FAU. On the other hand, reproducibility has no meaning if different measuring principles (attenuation vs. nephelometry) or very different wavelengths are used.

Self-monitoring of water quality in sewer systems using absorbance of ultraviolet and visible light.

Continuous pollution measurement is interesting to optimize the operation of sanitary facilities as well as to minimize the stormwater discharges. An experimental study was carried out for the determination of Suspended Solids (SS) and Chemical Oxygen Demand (COD) concentrations in combined sewers using ultraviolet and visible absorbances. The maintenance of the measurement system requires six hours a month for the cleaning of the hydraulic feeding system and adjustment of the optical device. The feeding system developed increased the representativeness and reliability of the pollution measurement, but needs to be validated on other measurement sites. The determination of SS concentrations from visible absorbances requires 2 calibration curves for dry and rainy weather respectively. The corresponding accuracies appear satisfactory when compared with the results of standard sampling/laboratory analysis. The accuracy of COD determination from ultraviolet absorbance is less satisfactory, but could perhaps be improved taking into account another parameter. Then the optical measurement of SS and COD is interesting to determine average or long term pollution loads, for example the yearly impact of urban stormwater discharges. With this kind of continuous and on-line measurement, it is possible to react with short delay to unexpected phenomena which could damage the environment or water treatment efficiency.

Molecular genetic analysis among subspecies of two Eurasian sturgeon species, Acipenser baerii and A. stellatus.

Two species, the Siberian sturgeon, Acipenser baerii, and stellate sturgeon, A. stellatus, were studied using mitochondrial DNA (mtDNA) (D-loop, cytochrome b (cyt-b) and ND5/6 genes) sequencing to determine whether traditionally defined subspecies correspond to taxonomic entities and conservation management units. Initially, several mtDNA regions for each taxon (A. baerii: 737 bp D-loop, 750 bp ND5, 200 bp ND6, and 790 bp cyt-b; A. stellatus: 737 bp D-loop and 600 bp ND5) were examined. The D-loop was the most variable region and was sequenced for 35 A. baerii and 82 A. stellatus individuals. No fixed, diagnostic differences were found between any of the subspecies. Geographical structuring of haplotypes was observed within A. baerii, and gene flow estimates suggest isolation of the A. baerii baicalensis subspecies and the Yenisie and Lena River populations. No intraspecific subdivisioning was found within the genetic data for A. stellatus. The use of the phylogenetic criterion (fixed diagnostic differences) for identifying conservation units is compared to the rationale and results of other methods. Overall, morphologically and geographically based subspecies designations within Acipenseridae may not directly correspond to the biological entities appropriate for management and should not be used for conservation programmes without genetic support.

[Problems of control of centralized sterilization in the therapeutic-prophylactic institutions]. / Voprosy kontrolia tsentralizovannoi sterilizatsii lechebno-profilakticheskikh uchrezhdeniiakh

The authors analyze their many-year experience in the work of the sanitary-epidemiological station on control of centralized sterilization departments (CSD) in medical institutions. This control system included preventive and current sanitary supervision, assessment of the efficacy and pecularities of the use of special equipment, the checking of the presterilization treatment and sterilization of medical objects. A necessity of improvment of methods of packing the materials and instruments subject to sterilization and of a thorough study of the sanitary-hygienic conditions of the CSD personnel was demonstrated.