Parasite fauna of the snakehead Channa argus warpachowskii from Primorsky Krai

Parasite fauna of the snakehead Channa argus warpachowskii was studied in water bodies of Primorsky Krai. Thirty-one parasite species were recorded in this host from the studied area according to original and literary data. Most part of these species are host-specific parasites of snakehead originated from Chinese-Indian region or parasites having a wide host range and able to infest almost all freshwater fishes. Moreover, three brackishwater species of parasites were found in the fishes introduced into the rivers of the southern part of Primorsky Krai. The causes of this invasion are discussed.     

Ecotoxicological assessment of several estuarine zones in the south of Primorsky Krai

A complex ecotoxicological assessment of several estuarine zones of the Razdol’naya, Barabashevka, Ryazanovka, and Gladkaya rivers in Amur Bay, and the Artyomovka and Sukhodol rivers in Ussyry Bay was carried out in 2007 and 2008. Bottom sediments in the estuary of the Kievka river were collected in 2009. The content of petroleum hydrocarbons was determined in the water and bottom sediments of riverine and marine sectors of estuaries and the total toxicity of bottom sediments was tested with the use of mysids. Bottom sediments from a small river on Reineke Island, in which the concentrations of primary pollutants corresponded to the background values for the entire Peter the Great Bay, were used as a control. The content of organochlorine pesticides in the muscles and liver of the Redeye Eastern Redfin (Tribolodon brandtii) was determined and molecular biomarkers of oxidative stress in organs of the Redlip Mullet (Liza haematocheila) analyzed. The amount of wastewater and pollutants flowing into Amur Bay and Ussyry Bay with some of the rivers was estimated. The correlation coefficient between the toxicity of bottom sediments and the petroleum hydrocarbons content in them was found. The higher sediment toxicity in the riverine zone, as compared to the marine zone, proves the concept of the “river-sea” biogeochemical barrier.     

Remote sensing and geographic information systems in the spatial temporal dynamics modeling of infectious diseases

Similar to species immigration or exotic species invasion, infectious disease transmission is strengthened due to the globalization of human activities. Using schistosomiasis as an example, we propose a conceptual model simulating the spatio-temporal dynamics of infectious diseases. We base the model on the knowledge of the interrelationship among the source, media, and the hosts of the disease. With the endemics data of schistosomiasis in Xichang, China, we demonstrate that the conceptual model is feasible; we introduce how remote sensing and geographic information systems techniques can be used in support of spatio-temporal modeling; we compare the different effects caused to the entire population when selecting different groups of people for schistosomiasis control. Our work illustrates the importance of such a modeling tool in supporting spatial decisions. Our modeling method can be directly applied to such infectious diseases as the plague, lyme disease, and hemorrhagic fever with renal syndrome. The application of remote sensing and geographic information systems can shed light on the modeling of other infectious disease and invasive species studies.     

Spatial and temporal structure of the infectious diseases incidence in the population of the south of the Russian Far East: system approach

New conception of the anthropo-parasitic system has been elaborated. Spatial and temporal structure of the infections diseases incidence in the Primorye Territory has been analysed on the base of this conception.     

Distribution of Triassic Foraminifers in the Limestone Massifs of the Dalnegorsk District,Primorsky Krai

Paleontological Journal - Foraminifer assemblages from five massifs of the Triassic limestones of the Dalnegorsk District have been described for the first time, and images of these foraminifers...     

Characterizing the spatial and temporal variation of malaria incidence in Bangladesh, 2007

ABSTRACT: BACKGROUND: Malaria remains a significant health problem in Bangladesh affecting 13 of 64 districts. The risk of malaria is variable across the endemic areas and throughout the year. A better understanding of the spatial and temporal patterns in malaria risk and the determinants driving the variation are crucial for the appropriate targeting of interventions under the National Malaria Control and Prevention Programme. METHODS: Numbers of Plasmodium falciparum and Plasmodium vivax malaria cases reported by month in 2007, across the 70 endemic thanas (sub-districts) in Bangladesh, were assembled from health centre surveillance reports. Bayesian Poisson regression models of incidence were constructed, with fixed effects for monthly rainfall, maximum temperature and elevation, and random effects for thanas, with a conditional autoregressive prior spatial structure. RESULTS: The annual incidence of reported cases was 34.0 and 9.6 cases/10,000 population for P. falciparum and P. vivax respectively and the population of the 70 malaria-endemic thanas was approximately 13.5 million in 2007. Incidence of reported cases for both types of malaria was highest in the mountainous south-east of the country (the Chittagong Hill Tracts). Models revealed statistically significant positive associations between the incidence of reported P. vivax and P. falciparum cases and rainfall and maximum temperature. CONCLUSIONS: The risk of P. falciparum and P. vivax was spatially variable across the endemic thanas of Bangladesh and also highly seasonal, suggesting that interventions should be targeted and timed according to the risk profile of the endemic areas. Rainfall, temperature and elevation are major factors driving the spatiotemporal patterns of malaria in Bangladesh.     

Structure of fruits and seeds and ways of dissemination of two species of the genus Aristolochia L. in Primorsky Krai

The fruit and seed structure features of Aristolochia manshuriensi and A. contorta growing in Primorskii Krai, Russia, were studied. It was revealed that seeds are dispersed generally by wind and to a lesser degree by river water streams, along which both Aristolochia species often grow. Vertebrate animals (birds, small rodents) appear to be chance agents of dissemination of these plants.     

Invertebrate drift in the piedmont part of the Kedrovaya River (Primorsky Krai,Russia) in warm season

Diurnal dynamics of invertebrate drift in the Kedrovaya River (Primorsky Krai, Russia), which flows in the zone of influence of the monsoon climate, has been studied. It has been shown that drifting invertebrates tend to shift from a predominantly daytime drift pattern to a distinguished nocturnal drift pattern during the frost-free period. The ratio of the total number of nighttime migrants to the total number of daytime migrants increased with every subsequent month. It has been proposed that the degree of light contrast between day and night can be significant in the regulation of nocturnal drift intensity.     

Merging spatial and temporal structure within a metapopulation model

Current research recognizes that both the spatial and temporal structure of the landscape influence species persistence. Patch models that incorporate the spatial structure of the landscape have been used to investigate static habitat destruction by comparing persistence results within nested landscapes. Other researchers have incorporated temporal structure into their models by making habitat suitability a dynamic feature of the landscape. In this article, we present a spatially realistic patch model that allows patches to be in one of three states: uninhabitable, habitable, or occupied. The model is analytically tractable and allows us to explore the interactions between the spatial and temporal structure of the landscape as perceived by the target species. Extinction thresholds are derived that depend on habitat suitability, mean lifetime of a patch, and metapopulation capacity. We find that a species is able to tolerate more ephemeral destruction, provided that the rate of the destruction does not exceed the scale of its own metapopulation dynamics, which is dictated by natural history characteristics and the spatial structure of the landscape. This model allows for an expansion of the classic definition of a patch and should prove useful when considering species inhabiting complex dynamic landscapes, for example, agricultural landscapes.     

Spatial and temporal community structure of desmids on a small spatial scale

Besides spatial heterogeneity, another important component of the diversity of protist communities is the variation in species assemblages through time. Despite its importance, temporal turnover of benthic communities has been studied to a lesser extent than spatial heterogeneity has. In this study, we examine the desmid assemblages on small spatial scale in relation to the spatial, temporal, and environmental parameters. The samples were collected within two different types of peatland localities in the Czech Republic over 3 years. The differences in species composition between samples were mainly correlated with the geographic distance, while the effects of the environmental and temporal variables were much weaker. Since the spatial heterogeneity of the assemblages was not induced by the variation of the environmental factors or by the restricted dispersal ability at such a small spatial scale, we assume that both the temporal stability and strong spatial autocorrelation might have been the result of a priority effect, with subsequent monopolization of resources. Stochasticity in colonization can introduce noise into the match between community composition and environmental conditions, which may result in stronger effect of the spatial parameters on the community structure.     

Real time bayesian estimation of the epidemic potential of emerging infectious diseases

Background

Fast changes in human demographics worldwide, coupled with increased mobility, and modified land uses make the threat of emerging infectious diseases increasingly important. Currently there is worldwide alert for H5N1 avian influenza becoming as transmissible in humans as seasonal influenza, and potentially causing a pandemic of unprecedented proportions. Here we show how epidemiological surveillance data for emerging infectious diseases can be interpreted in real time to assess changes in transmissibility with quantified uncertainty, and to perform running time predictions of new cases and guide logistics allocations.

Methodology/Principal Findings

We develop an extension of standard epidemiological models, appropriate for emerging infectious diseases, that describes the probabilistic progression of case numbers due to the concurrent effects of (incipient) human transmission and multiple introductions from a reservoir. The model is cast in terms of surveillance observables and immediately suggests a simple graphical estimation procedure for the effective reproductive number R (mean number of cases generated by an infectious individual) of standard epidemics. For emerging infectious diseases, which typically show large relative case number fluctuations over time, we develop a Bayesian scheme for real time estimation of the probability distribution of the effective reproduction number and show how to use such inferences to formulate significance tests on future epidemiological observations.

Conclusions/Significance

Violations of these significance tests define statistical anomalies that may signal changes in the epidemiology of emerging diseases and should trigger further field investigation. We apply the methodology to case data from World Health Organization reports to place bounds on the current transmissibility of H5N1 influenza in humans and establish a statistical basis for monitoring its evolution in real time.     

Characteristic of the etiologic structure of acute enteric infections in adults based on the data from infectious diseases hospital

Study of the etiologic spectrum of sporadic cases of causative agents of acute enteric infections (AEI) in 753 patients aged 15-85 years old using polymerase chain reaction (PCR) was performed in the infectious diseases hospital during 12 months. It was shown that detection of the causative agents of AEI by PCR was 2.2 times more effective than routine microbiologic diagnostics supplemented with test of feces on rotavirus by ELISA method and allowed to detect etiologic agent in 54.3% of the patients. Viral etiology of AEI was determined in 22.6% of the patients. The most significant causative agents of AEI comparable on the rate of detection with salmonella and shigella were genotype 2 noroviruses and group A rotaviruses which were isolated in 10.4 and 8.9% of the patients respectively. Seasonal change of dominating viral pathogens causing diarrheal diseases was noted: predominance of group A rotaviruses during winter-spring period, noroviruses--during spring-summer months, and astroviruses--during fall and in the beginning of winter.     

Biases in the estimation of spatial egg aggregation and association based on emergence data

Spatial aggregation and association of conspecific and allospecific eggs over resource patches have often been estimated based on emergence data. However, intra-specific competition reduces the number of emergents of conspecifics, and inter-specific competition reduces the number of emergents of allospecifics, causing biases in the estimation of spatial distribution of eggs using emergence data. The present study investigated, by laboratory experiments using drosophilids and simulation models, how the use of emergence data causes such biases. In the laboratory experiments, females were allowed to oviposit over resource patches, and spatial aggregation and association of eggs were examined. The number of emergents from each resource patch was then estimated from the density-survival relationship, and spatial aggregation and association of emerging adults thus estimated were compared with those of eggs. In the simulation models, the spatial distributions of adults emerging from eggs that varied in their degree of spatial aggregation were evaluated under different intensities of intra- and/or inter-specific competition. Both laboratory experiments and simulations indicate that the use of emergence data always causes an underestimation of spatial aggregation and association of eggs. Relaxation of intra- and inter-specific competition by addition of extra resources would improve the estimation of spatial egg distribution based on emergence data.     

Genetic load of hereditary diseases in populations of the Krasnodar Krai]

Medico-genetical study of populations living in Krasnodar district was carried out. The mean value of genetic load contributed by autosomal dominant diseases composed 0.92 +/- 0.06, this value being 0.56 +/- 0.04 for autosomal recessive and 0.36 +/- 0.05 for X-linked recessive disorders per one thousand. Comparative analysis of genetical load in urban and rural populations demonstrated that they had no differences in relation to genetical load contributed by autosomal recessive and X-linked recessive disorders. At the same time, significant differences were noted between the populations concerning genetic load contributed by autosomal-dominant disorders.     

High-resolution spatial and temporal analysis of phytoalexin production in oats

The production of oat (Avena sativa L.) phytoalexins, avenanthramides, occurs in response to elicitor treatment with oligo-N-acetylchitooligosaccharides. In this study, avenanthramides production was investigated by techniques that provide high spatial and temporal resolution in order to clarify the process of phytoalexin production at the cellular level. The amount of avenanthramides accumulation in a single mesophyll cell was quantified by a combination of laser micro-sampling and low-diffuse nanoflow liquid chromatography–electrospray ionization tandem mass spectrometry (LC–ESI-MS/MS) techniques. Avenanthramides, NAD(P)H and chlorophyll were also visualized in elicitor-treated mesophyll cells using line-scanning fluorescence microscopy. We found that elicitor-treated mesophyll cells could be categorized into three characteristic cell phases, which occurred serially over time. Phase 0 indicated the normal cell state before metabolic or morphological change in response to elicitor, in which the cells contained abundant NAD(P)H. In phase 1, rapid NAD(P)H oxidation and marked movement of chloroplasts occurred, and this phase was the early stage of avenanthramides biosynthesis. In phase 2, avenanthramides accumulation was maximized, and chloroplasts were degraded. Avenanthramides appear to be synthesized in the chloroplast, because a fluorescence signal originating from avenanthramides was localized to the chloroplasts. Moreover, our results indicated that avenanthramides biosynthesis and the hypersensitive response (HR) occurred in identical cells. Thus, the avenanthramides production may be one of sequential events programmed in HR leading to cell death. Furthermore, the phase of the defense response was different among mesophyll cells simultaneously treated with elicitor. These results suggest that individual cells may have different susceptibility to the elicitor. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Generative and somatic production of female sturgeon at a research farm in Primorsky Krai as a basis for manufacturing gastronomic caviar

The generative and somatic characteristics of female sturgeon of five species and three hybrid forms, which were reared at the TINRO Center’s warm-water cage farm at the north of Primorsky Krai and used in caviar production, are considered. Data on the somatic growth, roe output, functional fecundity, mean egg weight, and gonadosomatic index of the female Amur Sturgeon, Kaluga, Siberian Sturgeon of the Lena and the Baikal populations, Sterlet of the Volga population, hybrids of Russian Sturgeon and Siberian Sturgeon, hybrids of Siberian Sturgeon and Amur Sturgeon, and hybrids of Kaluga and Amur Sturgeon are analyzed. The sexual maturity age and interspawning intervals are defined in the studied females. Domesticated females of all the species are shown to mature a few years earlier than those in natural conditions and to have a greater body weight. The interspawning intervals shorten by a few years in domesticated females. Most female Sterlet and some females from both populations of Siberian Sturgeon spawn annually, while the remainder spawn once in 2 years. The interspawning intervals in two species of sturgeon that inhabit the Amur River and in hybrid forms usually last for 2 years. With age, values of characteristics such as roe amount, fecundity, mean egg weight, and roe output relative to body weight grow in females spawning for the second time in the warm-water farm. The maximum roe output is found in female Kalugas at the second spawning. Then the species follow in the order of decreasing of roe output: Amur Sturgeon, hybrids of Amur Sturgeon with Kaluga, hybrids of Siberian Sturgeon with Amur Sturgeon, hybrids of Russian Sturgeon with Siberian Sturgeon, Siberian Sturgeon of the Baikal population, Siberian Sturgeon of the Lena population, and Sterlet. The hybrid between the Russian Sturgeon and Siberian Sturgeon shows the best processability and survivability characteristics; the Amur Sturgeon and Sterlet follow.     

Community structure in north temperate ants: temporal and spatial variation

Summary Ant communities in Vermont and New York woods were sampled in four time periods to determine species composition, relative abundances, and nest locations in space. The Vermont community was richer, containing more species and higher nest densities than New York. Both communities followed the geometric distribution of species abundances, suggesting that a single resource was mediating competition. The resource most clearly implicated was suitable nest sites, principally pre-formed plant cavities. Nonrandom species associations, underdispersion in every season, and the occurrence of incipient nests overwintering aboveground all implicated shortage of such cavities. Furthermore, microhabitat differences which produce suitable nest sites occur over a very small scale in these communities.     

Microfluorimetric analysis of spatial and temporal patterns of immobilized cell growth

Pronounced spatial nonuniformities in cell density, physiology, and activity frequently arise within densely packed immobilized cell supports. For a more fundamental understanding of immobilized cell phenomena, we have developed high-resolution microfluorimetric procedures to analyze local variations in both immobilized cell loading and growth rate. Fluorescent staining of total cellular DNA provides a measure of local biomass density. Actively growing (DNA synthesizing) cells are marked by pulse-labeling newly synthesized DNA with the thymine analog, bromouracil. An immunofluorescent technique allows subsequent detection of spatial variations in DNA synthesis rates. These procedures enable the influence of mass-transfer limitations and other immobilization effects on cell distribution and activity to be readily quantified. We demonstrate this approach through analysis of the patterns of growth of Escherichia coli entrapped within Sr-alginate gel beads. The experimental techniques are potentially applicable to a variety of other aggregate cell systems.