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Municipal activated sludge can be used for polyhydroxyalkanoate (PHA) production, when supplied with volatile fatty acids. In this work, standardized PHA accumulation assays were performed with different activated sludge to determine (1) the maximum biomass PHA content, (2) the degree of enrichment (or volume-to-volume ratio of PHA-accumulating bacteria with respect to the total biomass), and (3) the average PHA content in the PHA-storing biomass fraction. The maximum attained biomass PHA content with different activated sludge ranged from 0.18 to 0.42 gPHA/gVSS, and the degree of enrichment ranged from 0.16 to 0.51 volume/volume. The average PHA content within the PHA-accumulating biomass fraction was relatively constant and independent of activated sludge source, with an average value of 0.58 ± 0.07 gPHA/gVSS. The degree of enrichment for PHA-accumulating bacteria was identified as the key factor to maximize PHA content when municipal activated sludge is directly used for PHA accumulation. Future optimization should focus on obtaining a higher degree of enrichment of PHA-accumulating biomass, either through selection during wastewater treatment or by selective growth during PHA accumulation. A PHA content in the order of 0.6 g PHA/g VSS is a realistic target to be achieved when using municipal activated sludge for PHA production.

This paper develops an integrated framework to forecast the volatility of crude oil prices by considering the impacts of extreme events (structural breaks). The impacts of extreme events are vital to improving prediction accuracy. Aiming to demonstrate the crude oil price fluctuation and the impacts of external events, this paper employs the complementary ensemble empirical mode decomposition (CEEMD). It decomposes the crude oil price into some constituents at various frequencies to extract a market fluctuation, a shock from extreme events and a long-term trend. The shock from extreme events is found to be the most crucial element in deciding the crude oil prices. Then we combine the iterative cumulative sum of squares (ICSS) test with the Chow test to get the structural breaks and analyze the extreme event impacts. Finally, this paper combines the structural breaks, the autoregressive integrated moving average (ARIMA) model, and the support vector machine (SVM) to make a forecast of the crude oil prices. The empirical process proves that the CEEMD-ARIMA-SVM model with structural breaks performs the best when compared with the other ARIMA-type models and SVM-type models. The framework offers an insightful view to help decision-makers and can be used in many areas., Supplementary Information: The online version contains supplementary material available at 10.1007/s00500-022-07276-5., Competing Interests: Conflict of interestNo potential conflict of interest was reported by the author(s)., (© The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2022.)

Small interfering RNAs (siRNA) are key regulators of gene expression that play essential roles in diverse biological processes. Trans-acting siRNAs (tasiRNAs) are a class of plant-endogenous siRNAs that lead the cleavage of nonidentical transcripts. TasiRNAs are usually involved in fine-tuning development. However, increasing evidence supports that tasiRNAs may be involved in stress response. Melon is a crop of great economic importance extensively cultivated in semiarid regions frequently exposed to changing environmental conditions that limit its productivity. However, knowledge of the precise role of siRNAs in general, and of tasiRNAs in particular, in regulating the response to adverse environmental conditions is limited. Here, we provide the first comprehensive analysis of computationally inferred melon-tasiRNAs responsive to two biotic (viroid-infection) and abiotic (cold treatment) stress conditions. We identify two TAS3-loci encoding to length (TAS3-L) and short (TAS3-S) transcripts. The TAS candidates predicted from small RNA-sequencing data were characterized according to their chromosome localization and expression pattern in response to stress. The functional activity of cmTAS genes was validated by transcript quantification and degradome assays of the tasiRNA precursors and their predicted targets. Finally, the functionality of a representative cmTAS3-derived tasiRNA (TAS3-S) was confirmed by transient assays showing the cleavage of ARF target transcripts., (� The Author(s) 2019. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

This paper presents a road surface scanning system that operates with a trichromatic line scan camera with light emitting diode (LED) lighting achieving road surface resolution under a millimeter. It was part of a project named Roadkills-Intelligent systems for surveying mortality of amphibians in Portuguese roads, sponsored by the Portuguese Science and Technology Foundation. A trailer was developed in order to accommodate the complete system with standalone power generation, computer image capture and recording, controlled lighting to operate day or night without disturbance, incremental encoder with 5000 pulses per revolution attached to one of the trailer wheels, under a meter Global Positioning System (GPS) localization, easy to utilize with any vehicle with a trailer towing system and focused on a complete low cost solution. The paper describes the system architecture of the developed prototype, its calibration procedure, the performed experimentation and some obtained results, along with a discussion and comparison with existing systems. Sustained operating trailer speeds of up to 30 km/h are achievable without loss of quality at 4096 pixels' image width (1 m width of road surface) with 250 µm/pixel resolution. Higher scanning speeds can be achieved by lowering the image resolution (120 km/h with 1 mm/pixel). Computer vision algorithms are under development to operate on the captured images in order to automatically detect road-kills of amphibians.

The geographic origins of African slave settlers and the Portuguese genetic contribution to the population of São Tomé (Gulf of Guinea) were assessed through the analysis of beta-globin haplotypes in 44 chromosomes bearing the betaS allele and through the study of the genetic variation in eight autosomal markers (APOA1, AT3, FY, LPL, OCA2, RB1, Sb19.3, and GC) informative for admixture in a sample of 224 individuals. The observed betaS haplotype distribution (36.4% Bantu, 52.3% Benin, 4.5% Cameroon, 4.5% Senegal, and 2.3% atypical) is in accordance with the historical information on the major geographic sources of slave settlers of São Tomé, although it captures a more important contribution of Central-West Africa regions than previously anticipated. European admixture, estimated to be 10.7 +/- 0.9%, has created a considerable level of genetic structure, as indicated by the finding of significant linkage disequilibrium between 33% of unlinked marker loci pairs. Recent admixture was found to have an important contribution to these values, since removal of individuals with Portuguese or Cape Verdian parents or grandparents from the sample dropped the miscegenation level to 6.5 +/- 0.8% and reduced significant linkage disequilibrium to 11% of unlinked marker pairs. Taken together, these results indicate that the peopling of São Tomé might have provided one of the first examples of the combination of diverse African contributions and European admixture that emerged from the overseas population relocations promoted by the Atlantic slave trade.