Kinetic and stoichiometric characterization of anoxic sulfideoxidation by SO-NR mixed cultures from anoxic biotrickling filters.

Monitoring the biological activity in biotrickling filters is difficult since it implies estimating biomass concentration and its growth yield, which can hardly be measured in immobilized biomass systems. In this study, the characterization of a sulfide-oxidizing nitrate-reducing biomass obtained from an anoxic biotrickling filter was performed through the application of respirometric and titrimetric techniques. Previously, the biomass was maintained in a continuous stirred tank reactor under steady-state conditions resulting in a growth yield of 0.328±0.045 g VSS/g S. To properly assess biological activity in respirometric tests, abiotic assays were conducted to characterize the stripping of CO2 and sulfide. The global mass transfer coefficient for both processes was estimated. Subsequently, different respirometric tests were performed: (1) to solve the stoichiometry related to the autotrophic denitrification of sulfide using either nitrate or nitrite as electron acceptors, (2) to evaluate the inhibition caused by nitrite and sulfide on sulfide oxidation, and (3) to propose, calibrate, and validate a kinetic model considering both electron acceptors in the overall anoxic biodesulfurization process. The kinetic model considered a Haldane-type equation to describe sulfide and nitrite inhibitions, a non-competitive inhibition to reflect the effect of sulfide on the elemental sulfur oxidation besides single-step denitrification since no nitrite was produced during the biological assays

Control of sulphide during anaerobic treatment of S-containing wastewaters by adding limited amounts of oxygen or nitrate

Sulphide generated during anaerobic treatment of S-containing wastewaters represents an environmental problem. Adding limited amounts of oxygen or nitrate (or nitrite) to biologically (or chemically) oxidise sulphide forms a simple process level strategy to control this problem. This short review evaluates the feasibility and limitations of this strategy on the basis of the results of bioreactor studies.Sulphide generated during anaerobic treatment of S-containing wastewaters represents an environmental problem. Adding limited amounts of oxygen or nitrate (or nitrite) to biologically (or chemically) oxidise sulphide forms a simple process level strategy to control this problem. This short review evaluates the feasibility and limitations of this strategy on the basis of the results of bioreactor studies.Spanish Ministry of Education and Science; AEA Technology Environment; Nova Energie; The Swedish Gas Centre; University of Southern Denmark

Classification and evaluation of educational apps for early childhood: Security matters

This study explored certain popular educational apps’ vital characteristics and potential profiles (n1 = 50) for kindergarten kids. The profile analysis involved a categorization ascended from an evaluation process conducted by pre-service early childhood teachers’ (n2 = 295) at the University of Crete, Greece, using a new instrument, validated in the present research, the ETEA-2 scale. The categorization criteria were the five dimensions of the ETEA-2: Learning, Suitability, Usability, Security, and Parental Control. The classification based on Latent Class Analysis led to three apps' profiles: Cluster/profile 1 includes apps that have high values in Learning, Usability, Suitability, and medium Parental Control and Security; Cluster/Profile 2 includes apps with medium Learning, Usability, Suitability, but low Parental Control and High Security; Cluster/Profile 3 includes apps with medium Learning, Usability, Suitability, but low Parental Control and low Security. This profile scheme is an indicative categorization summarizing the crucial features that popular apps possess and can help parents and/or educators’ decision-making on choosing the desirable application for their kids. Moreover, from an independent evaluation of these specific fifty apps sought on the internet, the members of Cluster2/Profile 2 were the most popular and preferable, as suggested by the number of downloads. This profile is distinguished for the security dimension. © 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature

Specific detection of OCT4 isoforms in inflammatory bowel disease

Background: Developmentally early cells are mobilized into peripheral blood in Crohn's disease (CD) patients. OCT4, is considered to be important in sustaining the pluripotency of stem cells. OCT4 splicing variants are differentially expressed in pluripotent and non-pluripotent cells. Our study aims to investigate the expression pattern of OCT4 variants and SOX-2, an essential factor implicated in self-renewal and pluripotency, in tissue and blood samples from patients with IBD. Methods: Peripheral blood and tissue samples were collected from patients with active CD and ulcerative colitis (UC), and from healthy individuals. OCT4 expression was documented by Western blot, immunohistochemistry and by reverse transcription-real- Time PCR. OCT4 isoform determination was documented using specific primers. SOX-2 expression levels were also evaluated. Results: OCT4 protein levels were significantly higher in CD tissue samples than in CD blood samples, and in UC tissue samples. OCT4 protein was localized mainly in the cytosol. In all samples, only the OCT4 pseudogenes and the OCT4B1 variant were detected. OCT4B1 expression levels were elevated in both tissue and blood samples from CD and UC cases compared to healthy controls. In CD patients only SOX-2 mRNA levels were found slightly increased compared to healthy controls. Conclusion: Our results suggest that OCT4 is expressed in patients with IBD. Furthermore, we found the presence of the OCT4B1 isoform in IBD in both tissue and blood samples. Our results have shown, that developmentally early cells might be mobilized into peripheral blood as result of tissue damage, indicating a possible role of these cells in repair of injured intestinal tract. © 2015 Maragkoudaki et al

Polymorphisms of Caspase 8 and Caspase 9 gene and colorectal cancer susceptibility and prognosis

Purpose: Caspase-8 (CASP8) and caspase-9 (CASP9) play crucial roles in regulating apoptosis, and their functional polymorphisms may alter cancer risk. Our aim was to investigate the association between CASP8 and CASP9 gene polymorphisms and colorectal cancer (CRC) susceptibility. Methods: A case-control study at 402 CRC patients and 480 healthy controls was undertaken in order to investigate the association between the genotype and allelic frequencies of CASP8 -652 6N ins/del and CASP9 -1263 A>G polymorphisms and the CRC susceptibility. The polymerase chain reaction (PCR) restriction fragment length polymorphism method was used and the incidence of polymorphisms on messenger RNA (mRNA) expression levels was detected by quantitative reverse-transcriptase PCR in CRC tissues. Results: No statistical significant association was observed between CASP8 -652 6N ins/del polymorphism frequencies and CRC susceptibility. CASP9 -1263 G allele was observed to be significant associated with reduced risk of CRC. Homozygotes for the -1263 GG CASP9 genotype, and hetrozygotes for the -1263 AG genotype expressed 6.64- and 3.69-fold higher mRNA levels of Caspase-9, respectively compared to the -1263 AA genotype cases. No significant association was observed between CASP9 -1263 A>G polymorphism and tumor characteristics. The CASP9 -1263 GG genotype was associated with increased overall survival in CRC patients. Conclusion: The CASP9 -1263 A>G polymorphism was observed to play a protective role in CRC predisposition, while the CASP9 -1263 GG genotype may confer a better prognosis at CRC patients. © 2011 Springer-Verlag

Improving our understanding of the environmental persistence of chemicals

Significant progress has been made in the scientific understanding of factors that influence the outcome of biodegradation tests used to assess the persistence (P) of chemicals. This needs to be evaluated to assess whether recently acquired knowledge could enhance existing regulations and environmental risk assessments. Biodegradation tests have limitations, which are accentuated for “difficult‐to‐test” substances, and failure to recognize these can potentially lead to inappropriate conclusions regarding a chemical's environmental persistence. Many of these limitations have been previously recognized and discussed in a series of ECETOC reports and workshops. These were subsequently used to develop a series of research projects designed to address key issues and, where possible, propose methods to mitigate the limitations of current assessments. Here, we report on the output of a Cefic LRI–Concawe Workshop held in Helsinki on September 27, 2018. The objectives of this workshop were to disseminate key findings from recent projects and assess how new scientific knowledge can potentially support and improve assessments under existing regulatory frameworks. The workshop provided a unique opportunity to initiate a process to reexamine the fundamentals of degradation and what current assessment methods can achieve by (1) providing an overview of the key elements and messages coming from recent research initiatives and (2) stimulating discussion regarding how these interrelate and how new findings can be developed to improve persistence assessments. Opportunities to try and improve understanding of factors affecting biodegradation assessments and better understanding of the persistence of chemicals (particularly UVCBs [substances of unknown or variable composition, complex reaction products, or biological materials]) were identified, and the workshop acted as a catalyst for further multistakeholder activities and engagements to take the persistence assessment of chemicals into the 21st century. Integr Environ Assess Manag 2021;17:1123–1135. © 2021 European Petroleum Refiners Association – Concawe Division. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC)