Microplastics found in the environment are often covered with a biofilm, which makes their analysis difficult. Therefore, the biofilm is usually removed before analysis, which may affect the ...microplastic particles or lead to their loss during the procedure. In this work, we used laser-based analytical techniques and evaluated their performance in detecting, characterizing, and classifying pristine and aged microplastics with a developed biofilm. Five types of microplastics from different polymers were selected (polyamide, polyethylene, polyethylene terephthalate, polypropylene, and polyvinyl chloride) and aged under controlled conditions in freshwater and wastewater. The development of biofilm and the changes in the properties of the microplastic were evaluated. The pristine and aged microplastics were characterized by standard methods (e.g., optical and scanning electron microscopy, and Raman spectroscopy), and then laser-induced breakdown spectroscopy (LIBS) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) were used. The results show that LIBS could identify different types of plastics regardless of the ageing and major biotic elements of the biofilm layer. LA-ICP-MS showed a high sensitivity to metals, which can be used as markers for various plastics. In addition, LA-ICP-MS can be employed in studies to monitor the adsorption and desorption (leaching) of metals during the ageing of microplastics. The use of these laser-based analytical techniques was found to be beneficial in the study of environmentally relevant microplastics.
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•Microplastics were aged in freshwater and wastewater.•Advanced laser-based techniques were tested for the detection of aged microplastics.•Raman spectroscopy detected and classified aged microplastics.•LIBS detected microplastics and biotic elements in the developed biofilm.•LA-ICP-MS detected metals in microplastics and in the developed biofilm.
This study investigates the effects of alloying elements on the microstructural evolution of Al-rich Al-Mn-Cu-(Be) alloys during solidification, and subsequent heating and annealing. The samples were ...characterised using scanning electron microscopy, energy dispersive X-ray spectroscopy, synchrotron X-ray diffraction, time-of-flight secondary-ion mass spectroscopy, and differential scanning calorimetry. In the ternary Al
94
Mn
3
Cu
3
(at%) alloy, the phases formed during slower cooling (≈1 K s
−1
) can be predicted by the known Al-Mn-Cu phase diagram. The addition of Be prevented the formation of Al
6
Mn, decreased the fraction of τ
1
-Al
29
Mn
6
Cu
4
, and increased the fraction of Al
4
Mn. During faster cooling (≈1000 K s
−1
), Al
4
Mn predominantly formed in the ternary alloy, whereas, in the quaternary alloys, the icosahedral quasicrystalline phase dominated. Further heating and annealing of the alloys caused an increase in the volume fractions of τ
1
in all alloys and Be
4
Al (Mn,Cu) in quaternary alloys, while fractions of all other intermetallic phases decreased. Solidification with a moderate cooling rate (≈1000 K s
−1
) caused considerable strengthening, which was reduced by annealing for up to 25% in the quaternary alloys, while hardness remained almost the same in the ternary alloy.
Purpose: Organic and integrated production of vegetables are the two most common production systems in Slovenia. The study analyzed two production systems with different cultures as alternatives with ...purpose to find the most appropriate variants.
Design/Methodology/Approach: The study based on the development and integration of developed specific technological- economic simulation models for the production of vegetables (salad, growing peppers, salad cucumbers, pickling cucumbers, round and cherry tomato) in greenhouse and multi-criteria decision analysis. The methodology of the study based on the DEX methodology and the analytical hierarchy process (AHP) of organic (ECO) and integrated production (IP) in greenhouse.
Results: The evaluation results show that both cultivation methods of commercially attractive vegetables in greenhouse are variable. In the case of integrated production, the assessment of multi-criteria decision analysis EC and DEXi showed that salad (Donertie F1) proved to be the best possible alternative. In the case of organic production, the multi-criteria analysis assessment of pickling cucumbers (Harmony F1) is the best possible business alternative.
Conclusion: For the further production planning process by decision maker is the ranking with Expert Choice (EC) more useful and precise, while the DEX evaluations are more descriptive.
Mutations in the X chromosomal tRNA 2′‑O‑methyltransferase FTSJ1 cause intellectual disability (ID). Although the gene is ubiquitously expressed affected individuals present no consistent clinical ...features beyond ID. In order to study the pathological mechanism involved in the aetiology of FTSJ1 deficiency-related cognitive impairment, we generated and characterized an Ftsj1 deficient mouse line based on the gene trapped stem cell line RRD143. Apart from an impaired learning capacity these mice presented with several statistically significantly altered features related to behaviour, pain sensing, bone and energy metabolism, the immune and the hormone system as well as gene expression. These findings show that Ftsj1 deficiency in mammals is not phenotypically restricted to the brain but affects various organ systems. Re-examination of ID patients with FTSJ1 mutations from two previously reported families showed that several features observed in the mouse model were recapitulated in some of the patients. Though the clinical spectrum related to Ftsj1 deficiency in mouse and man is variable, we suggest that an increased pain threshold may be more common in patients with FTSJ1 deficiency. Our findings demonstrate novel roles for Ftsj1 in maintaining proper cellular and tissue functions in a mammalian organism.
•FTSJ1 encodes a tRNA methyltransferase.•Mutations in FTSJ1 cause non-syndromic intellectual disability (ID).•Ftsj1 gene trapped mice are affected by ID and show other syndromic features.•Some of these features were identified in patients with FTSJ1 mutations.
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