[en] The development of microbial community–based biological indicators for assessing aquatic ecological status is urgently needed in heavily impaired regions, due to the local extinction of traditional indicator macro-organisms. The aim of this study was to develop and validate a microbial community–based index of biotic integrity (MC-IBI) to assess the health of wetlands in Suzhou, China. High-throughput sequencing was used to obtain information about microbial communities in wetlands and to investigate the health of the wetlands. When constructing the index, we selected what we considered were the most important environmental factors and biological parameters, and identified sensitive and tolerant species. We then used the index to evaluate the health of the inflows and outflows of 15 wetlands in Suzhou. The results showed that, of the 30 samples collected at the 10 impacted inflow sites, 2 were classified as “poor,” 5 were “commonly,” 18 were sub-healthy, and 5 were healthy; at the restored outflow sites, 24 were “healthy” and 6 were “sub-healthy.” The health was worst at the inflows of wetlands that received agricultural effluent, followed by those that received industrial effluent, and was best at those that received urban effluent. The results from our study show that this newly developed MC-IBI gave reasonable evaluations of the health of wetland ecosystems. This application demonstrates that the evaluation system was feasible and we suggest that evaluations that further MC-IBI evaluation approaches should be developed further in the future.

[en] Several serum and cellular biologic tumor markers in testicular cancer are studied. The role of alpha-fetoprotein and human chorionic gonadotropin in staying testicular tumors is reported and the use of radioimmunoassay is considered. (M.A.C.)

[en] Highlights: • Bacterial taxonomic compositions changed from the dominance of Firmicutes to Proteobacteria alongside antibiotic transmission. • Ofloxacin and tetracycline were most predictive antibiotics for bacterial and functional network properties, respectively. • Modularity was consistently much higher in functional networks than bacterial networks. • Modularity of association networks can be an indicator of system stability for microbial communities. • Microbial community assembly is one of the primary mechanisms underlying microbial interactions. Interspecies interaction is an essential mechanism for bacterial communities to develop antibiotic resistance via horizontal gene transfer. Nonetheless, how bacterial interactions vary along the environmental transmission of antibiotics and the underpinnings remain unclear. To address it, we explore potential microbial associations by analyzing bacterial networks generated from 16S rRNA gene sequences and functional networks containing a large number of antibiotic-resistance genes (ARGs). Antibiotic concentration decreased by more than 4000-fold along the environmental transmission chain from manure samples of swine farms to aerobic compost, compost-amended agricultural soils, and neighboring agricultural soils. Both bacterial and functional networks became larger in nodes and links with decreasing antibiotic concentrations, likely resulting from lower antibiotics stress. Nonetheless, bacterial networks became less clustered with decreasing antibiotic concentrations, while functional networks became more clustered. Modularity, a key topological property that enhances system resilience to antibiotic stress, remained high for functional networks, but the modularity values of bacterial networks were the lowest when antibiotic concentrations were intermediate. To explain it, we identified a clear shift from deterministic processes, particularly variable selection, to stochastic processes at intermediate antibiotic concentrations as the dominant mechanism in shaping bacterial communities. Collectively, our results revealed microbial network dynamics and suggest that the modularity value of association networks could serve as an important indicator of antibiotic concentrations in the environment.

[en] The purpose of this preliminary study was to evaluate the prospects for using populations of the great tit (Parus major) and the pied flycatcher (Ficedula hypoleuca) in ecological monitoring of territories contaminated with radionuclides. Studies were performed in the summer of 1992 in birch forests of the Southern Urals. Artificial nesting sites (log houses) located 1.5 m above the ground were distributed over territories of two test plots: 30 log houses on the contaminated plot and 60 on the control plot (contamination with Sr-90 1.5 and 2 · 10^-3 mCi/m², respectively). The nesting success in the great tit was similar on both plots, whereas that in the pied flycatcher was significantly greater on the control plot (in a open-quotes cleanclose quotes forest). Pied flycatchers build their nests out of highly radioactive materials, whereas great tits use nonradioactive or weakly emitting materials. Hence, pied flycatcher's nestlings receive a significant radiation dose from components of the nest: From the moment of egg laying, this dose amounts to 0.5 rem. The pied flycatcher can be used as an indicator of radioactive contamination. This species is more sensitive than the great tit, which has been successfully used as an indicator for monitoring the industrial air pollution

[en] Highlights: • Many studies have quantified plastic loads in seabirds' stomachs. • Assessing impact of ingested plastic would benefit from retention time estimates. • Size of plastic particles is assumed to be related to wear and retention times. • We compared particle size relative to retention time in two seabird species. • Relative to time, particle volume was reduced in one species, but not in the second. Many studies have quantified plastic loads in seabirds' stomachs but provide imprecise estimates of retention time. Quantifying retention time is fundamental for assessing biological impact and for the use of plastic as bioindicators of plastic pollution. Presumably, plastic is retained in the grinding section of the stomach (gizzard or ventriculus) until ground small enough and particles then pass into intestines and are defecated. We assume that particle size is related to time in the ventriculus and compared size of plastic particles in juveniles, which were exposed to plastic for a known time, to non-juveniles which were exposed for an unknown longer period. Plastic particles from Northern Fulmars (Fulmarus glacialis) were of similar size between groups suggesting similar wear and retention time. Cassin's Auklet (Ptychoramphus aleuticus) juveniles contained larger particles than adults suggesting particles retained in adults were worn down and thus held for a longer period.

[en] Highlights: • SCCPs and MCCPs were tested in 62 pairs of human hair and nails from North China. • CP concentrations in hair were significantly higher than those in nails. • The homologue profiles of CPs in hair were similar to those in nails. • The CP levels positively correlated with age for hair, whereas negative linear correlations were observed in nails. • Age and the MCCPs/SCCPs ratios might influence the accumulation of CPs in hair and nails. Most of the studies on short- and medium-chain chlorinated paraffins (SCCPs and MCCPs) in human tissues have focused on human milk and blood. However, little is known about the occurrence of CPs in human hair and nails. In this study, SCCPs and MCCPs were analyzed in 62 pairs of human hair and nails from North China. Median concentrations (range) of SCCPs and MCCPs in human hair were 239 (19.2–877) and 325 (16.9–893) ng/g dw, respectively, all of which were significantly higher than 154 (57.7–355) and 233 (61.0–476) ng/g dw, respectively, in nail samples (p < 0.05). The homologue profiles of CPs in human hair were similar to those in nails, where SCCPs and MCCPs were dominated by C₁₀Cl_6–7 and C₁₄Cl_7–8, respectively. A significant positive relationship was observed between CP levels and age of people for hair, whereas negative linear correlations were observed for nails. The redundancy analysis indicated that age of people might be the main influencing factor on the accumulation of CPs in hair and nails. The present study performed comprehensive evaluation of CP exposure levels in human hair and nail and highlights the need for more data on relationship between internal and external exposure to CPs.

No abstract available

[en] To inhibit Escherichia coli O157:H7 and determine a indicator bacteria for irradiation procedure in minced meat, this study evaluated increased irradiation doses on five strains of each of the following bacteria: 5 strains E. coli type 1 and 4 strains E. coli O157:H7. E. coli type 1 mixture was added into the mixed in ratio 1:100000 of E. coli type l to samples and E. coli O157:H7 mixture was added into the mixed in five different ratios namely 1:10, 1:100, 1:1000, 1:10000, 1:100000 of E coli O157:H7 in the minced meat. A range of irradiation doses from 1 kGy to 4 kGy was investigated for the inhibition of E. coli O157:H7 and the resistance of E. coli type 1 to irradiation. After irradiation, E. coli O157:H7 and E. coli type 1 were counted in the irradiated minced meat by using MPN techniques. D₁₀ values of each bacteria were be measured as 0.3 kGy and 0.55 kGy for E. coli 0157:H7 and E. coli type 1 respectively. This study showed that 1.5 kGy irradiation can inactivate 10⁵ g/O157:H7 serotype and 10³ g / E. coli type 1, this inactivation level is adequate for safety consumption of minced meat such as hamburger even if undercooking conditions. Increased irradiation doses were the most effective on E. coli O157:H7. The results show that E. coli type 1 is more resistant to than E. coli O157:H7 and other natural non-Pathogenic cohabitant bacteria and E. coli type 1 is an adequate indicator for the efficiency of irradiation against to O157:H7 serotype in minced meat

[en] In nuclear facilities, such as Chalk River Laboratories, dose to the atomic radiation workers (ARWs) is assessed routinely by using physical dosimeters and bioassay procedures in accordance with regulatory recommendations. However, these procedures may be insufficient in some circumstances, e.g., in cases where the reading of the physical dosimeters is questioned, in cases of radiation accidents where the person(s) in question was not wearing a dosimeter, or in the event of a radiation emergency when an exposure above the dose limits is possible. The desirability of being able to assess radiation dose on the basis of radio-biological effects has prompted the Dosimetric Research Branch to investigate the suitability of biological devices and techniques that could be used for this purpose. Current biological dosimetry concepts suggest that there does not appear to be any bio-indicator that could reliably measure the very low doses that are routinely measured by the physical devices presently in use. Nonetheless, bio-indicators may be useful in providing valuable supplementary information in cases of unusual radiation exposures, such as when the estimated body doses are doubtful because of lack of proper physical measurements, or in cases where available results need to be confirmed for medical treatment plannings. This report evaluates the present state of biological dosimetry and, in particular, assesses the efficiency and limits of individual indicators. This has led to the recommendation of a few promising research areas that may result in the development of appropriate biological dosimeters for operational and emergency needs at Chalk River

[en] Metals Cu, Cr, Cd, Zn, Mn and Pb, were measured in seafood items from Sepetiba Bay, Rio de Janeiro, The results showed that the highest concentrations are presented by filter-feeding molluscs, probably due to their relationship with the bay's suspended particulate matter. (M.A.C.)