Sredstva za zaštitu bilja na poljoprivrednim površinama – rezidue u gujavicama i procjena potencijalno toksičnih učinaka na okoliš

The environmental risk assessment of plant protection products for soil organisms is mainly based on the results of laboratory and extended laboratory studies while the link from the laboratory to realistic field conditions over several seasons is not well established. The current environmental risk assessment is applied to a single active ingredient and does not consider that soil organisms are exposed to varying degrees to a mixture of active ingredients from different pesticides. In this study, earthworm samples were collected from eight fields in Croatia during two growing seasons and analyzed for 300 active ingredients. The concentrations of 26 analyzed active ingredients ranged between 0.000 and 0.247 mg/kg earthworm fresh weight with a mean of 0.005 mg/kg earthworm fresh weight. The percentage of samples with values below the limit of detection (LOD = ½ LOQ), values below the limit of quantification (LOQ = 0.001 mg/kg) and values above LOQ were 33, 44 and 23 %, respectively. Based on publicly available draft assessment reports from European Commission and European Food Safety Authority, degradation parameters (DT50, DT90) were used to calculate degradation curves and the current concentration in soil at the date of earthworm sampling. Subsequently, compoundspecific bioconcentration factors in soil were determined by dividing the analyzed pesticide residues in earthworms by the calculated concentrations in soil. The results of the study showed that most active ingredients do not pose a risk to earthworms and have no secondary poisoning potential to birds and mammals that feed on them. The retrospective analysis method of analytically measured neonicotinoid residues in earthworm samples can be reliably used to calculate degradation and concentration curves in soil at the time of sampling.Procjena ekološkog rizika sredstava za zaštitu bilja za organizme u tlu uglavnom se temelji na rezultatima laboratorijskih i proširenih laboratorijskih studija dok veza između laboratorija i realnih poljskih uvjeta tijekom nekoliko sezona nije dobro utvrđena. Trenutna procjena rizika za okoliš primjenjuje se na pojedinačne aktivne tvari i ne uzima u obzir da su organizmi u tlu izloženi mješavini mješavini aktivnih tvari različitih pesticida. U istraživanju su prikupljeni uzorci gujavica s osam polja u Hrvatskoj tijekom dvije vegetacijske sezone. Analizirani su na 300 aktivnih tvari. Koncentracije 26 analiziranih aktivnih tvari kretale su se od 0,000 do 0,247 mg/kg svježe mase gujavica sa srednjom vrijednosti od 0,005 mg/kg svježe mase gujavica. Postotak uzoraka s vrijednostima ispod granice detekcije (LOD = ½ LOQ), vrijednosti ispod granice kvantifikacije (LOQ = 0,001 mg/kg) i vrijednosti iznad LOQ iznosio je 33, 44 and 23%. Na temelju javno dostupnih nacrta izvješća o procjeni Europske komisije i Europske agencije za sigurnost hrane, parametri degradacije (DT50, DT90) korišteni su za izračunavanje krivulja razgradnje i koncentracije u tlu u vrijeme uzorkovanja gujavica. Potom su određeni faktori biokoncentracije specifičnih za spoj u tlu dijeljenjem analiziranih ostataka pesticida u gujavicama s izračunatim koncentracijama u tlu. Rezultati istraživanja pokazali su da većina aktivnih tvari ne predstavlja rizik za gujavice i nema sekundarni potencijal trovanja za ptice i sisavce koji se njima hrane. Metoda retrospektivne analize analitički izmjerenih rezidua neonikotinoida u uzorcima gujavica može se pouzdano koristiti za izračunavanje krivulja razgradnje i koncentracije u tlu u vrijeme uzorkovanja

Electrolysis in reduced gravitational environments: current research perspectives and future applications

Electrochemical energy conversion technologies play a crucial role in space missions, for example, in the Environmental Control and Life Support System (ECLSS) on the International Space Station (ISS). They are also vitally important for future long-term space travel for oxygen, fuel and chemical production, where a re-supply of resources from Earth is not possible. Here, we provide an overview of currently existing electrolytic energy conversion technologies for space applications such as proton exchange membrane (PEM) and alkaline electrolyzer systems. We discuss the governing interfacial processes in these devices influenced by reduced gravitation and provide an outlook on future applications of electrolysis systems in, e.g., in-situ resource utilization (ISRU) technologies. A perspective of computational modelling to predict the impact of the reduced gravitational environment on governing electrochemical processes is also discussed and experimental suggestions to better understand efficiency-impacting processes such as gas bubble formation and detachment in reduced gravitational environments are outlined

Tumor budding correlates with tumor invasiveness and predicts worse survival in pT1 non-muscle-invasive bladder cancer

Tumor budding is defined as a single cell or a cluster of up to 5 tumor cells at the invasion front. Due to the difficulty of identifying patients at high risk for pT1 non-muscle-invasive bladder cancer (NMIBC) and the difficulties in T1 substaging, tumor budding was evaluated as a potential alternative and prognostic parameter in these patients. Tumor budding as well as growth pattern, invasion pattern and lamina propria infiltration were retrospectively evaluated in transurethral resection of the bladder (TURB) specimens from 92 patients with stage pT1 NMIBC. The presence of tumor budding correlated with multifocal tumors (p = 0.003), discontinuous invasion pattern (p = 0.039), discohesive growth pattern (p < 0.001) and extensive lamina propria invasion (p < 0.001). In Kaplan–Meier analysis, tumor budding was associated with significantly worse RFS (p = 0.005), PFS (p = 0.017) and CSS (p = 0.002). In patients who received BCG instillation therapy (n = 65), the absence of tumor budding was associated with improved RFS (p = 0.012), PFS (p = 0.011) and CSS (p = 0.022), with none of the patients suffering from progression or dying from the disease. Tumor budding is associated with a more aggressive and invasive stage of pT1 NMIBC and a worse outcome. This easy-to-assess parameter could help stratify patients into BCG therapy or early cystectomy treatment groups