Evaluation of invasive Acacia species compost as alternative horticultural organic substrates

The physical and chemical characteristics of composts of invasive Acacia longifolia and Acacia melanoxylon shrubs were evaluated to identify compost limitations as a substrate component. The bulk density was 85% of the total volume. Air capacity, the easily available water and buffering capacity were also within acceptable recommended values for horticultural substrates. With increased composting time the physical characteristics of the composts improved, but the same was not true for chemical characteristics. It is recommended to use these acacia composts in mixtures with peat which increases the content of organic matter and the C/N ratio, and decreases the pH and the electrical conductivity, of the final substrates

Effects of soil, root mycorrhization, organic and phosphate fertilization, in organic lettuce production

The influence of organic and phosphate fertilization, and root mycorrhization, in organic lettuce production, was assessed with factorial treatment combinations of: soil type (SOP – soil from organic and SCP – soil from conventional production) and organic fertilizer (0, 2 and 4 t ha-1) in the first trial; mycorrhizal inoculation (mycorrhized and non-mycorrhized plants) and Gafsa phosphate (0, 100 and 200 kg P2O5 ha-1) in the second. Lettuce yield decreased in the SCP with the application of increasing rates of organic fertilizer due to the very high electrical conductivity (50.1 dS m-1) and lack of maturation of this fertilizer. However, the harmful effects of the organic fertilizer were minimized in the SOP. The application of increasing rates of Gafsa phosphate increased lettuce yield and nutrient uptake. However, the mycorrhization did not increase lettuce yield and, for mycorrhized lettuces, yield did not increase with the highest rate of Gafsa phosphate application

Contribution for wellbeing of people working in urban organic allotment gardens

Poster presented at XXX International Horticultural Congress, 12-16 August 2018, Istambul, TurkeyN/

Active learning in the detection of anomalies in cryptocurrency transactions

The cryptocurrency market has grown significantly, and this quick growth has given rise to scams. It is necessary to put fraud detection mechanisms in place. The challenge of inadequate labeling is addressed in this work, which is a barrier to the training of high-performance supervised classifiers. It aims to lessen the necessity for laborious and time-consuming manual labeling. Some unlabeled data points have labels that are more pertinent and informative for the supervised model to learn from. The viability of utilizing unsupervised anomaly detection algorithms and active learning strategies to build an iterative process of acquiring labeled transactions in a cold start scenario, where there are no initial-labeled transactions, is being investigated. Investigating anomaly detection capabilities for a subset of data that maximizes supervised models’ learning potential is the goal. The anomaly detection algorithms under performed, according to the results. The findings underscore the need that anomaly detection algorithms be reserved for situations involving cold starts. As a result, using active learning techniques would produce better outcomes and supervised machine learning model performance.FCT - Fundação para a Ciência e a Tecnologia(UIDB/00319/2020

PRUNING SYSTEM EFFECT ON GREENHOUSE GRAFTED TOMATO YIELD AND QUALITY

This study aimed to evaluate the effects on tomato yield and quality of three pruning systems (2, 3 and 4 stems) of grafted plants (cv. Vinicio and Multifort) used to prevent the incidence of soil diseases. It was also investigated if the two stems from nodes of the cotyledon leaves improved crop performance compared to the two stems from the first true leaves nodes. The experiment was conducted in the spring/summer season, under greenhouse conditions at NW Portugal, with a randomized block design with 3 blocks and the four pruning crop treatments. Total yield was significantly increased for the double-stem tomato crop, without significant differences between both stem nodes position (26.5 kg m-2), compared to plants with 3 and 4 stems (19.5 kg m-2). The fruit grade between 57-102 mm represented 96.3% of total yield and this was similar for all plant treatments. Fruit quality was not influenced by the pruning systems and mean characteristics were: fruit firmness (1.0 kg), content of soluble solids (5.1°Brix), acidity (1.0 g 100 g-1), pH (4.4), dry mater content (4.9%), and unblemished fruits (90.9%). Higher yield and fruit quality from double-stem tomato plants offset the increased planting labour and higher plant cost, compared to the 3 and 4 stems grafted plants. The similar results obtained with double-stem plants from cotyledon leaves nodes and from the first true leaves suggest that the former plants should not be recommended due to the higher nursery pruning care they need

The effect of ambient pressure on the heat transfer of a water spray

The present work is aimed at quantifying the effects of ambient pressure in the heat transfer at single injections of a full cone spray over a hot metal surface. The experimental configuration is that of a spray impinging down perpendicularly onto a flat surface located at 55 mm inside an injection chamber. The experiments were conducted for prescribed initial wall temperatures ranging from single phase to local nucleate boiling and transition regimes of heat transfer. Ambient pressures ranged from atmospheric to 30 bar. The analysis is based on spatial resolved measurements of the instantaneous surface temperature during the injection period. The measurements are then processed in order to obtain estimates of the time-averaged values of the local heat flux. The overall cooling rate is also obtained by integrating the local values within the total area of the spray impact Results show that the amount of heat extracted by the impinging spray increases 3.4 times when ambient pressure is increased from atmospheric to 20 bar at the same superheating degree at the wall of 45 degrees C. This corresponds to an increase from 13.3% to 47.7% in the ratio between the actual cooling and the theoretical maximum cooling, defined here as cooling efficiency. This is a result of a better spreading of the liquid film at the wall, covering a larger footprint upon impact. Instantaneous peak heat flux is also increased, as a clear indication of the improved heat transfer between the impinging droplets and the wall.The work presented herein derives from a broader research program devised to develop a system for in cylinder cooling of internal combustion engines using high pressure water sprays produced by gasoline direct injectors.The authors would like to acknowledge LiquidPiston INC. for providing all the laboratorial conditions to perform the experiments, MEtRICs - Mechanical Engineering and Resource Sustainability Centre (UID/EMS/04077/2019), and Diogo Ferreira for aiding in the highspeed visualization setup and experiments. T. Costa is supported by the Portuguese Foundation for Science and Technology (FCT) under the PhD grant PD/BD/105929/2014, MIT Portugal Program, and F.P. Brito is supported by FCT under the Post doctoral grant SFRH/BPD/89553/2012 and J. Martins is supported by the FCT grant SFRH/BSAB/142994/2018, financed by FEDER funds through Programa Operacional Fatores de Competitividade - COMPETE and National funds through PIDDAC and FCT

The D1822V APC polymorphism interacts with fat, calcium, and fiber intakes in modulating the risk of colorectal cancer in Portuguese persons

Background - Both genetic and environmental factors affect the risk of colorectal cancer (CRC). Objective - We aimed to examine the interaction between the D1822V polymorphism of the APC gene and dietary intake in persons with CRC. Design - Persons with CRC (n = 196) and 200 healthy volunteers, matched for age and sex in a case-control study, were evaluated with respect to nutritional status and lifestyle factors and for the D1822V polymorphism. Results - No significant differences were observed in energy and macronutrient intakes. Cases had significantly (P < 0.05) lower intakes of carotenes, vitamins C and E, folate, and calcium than did controls. Fiber intake was significantly (P = 0.004) lower in cases than in controls, whereas alcohol consumption was associated with a 2-fold risk of CRC. In addition, cases were significantly (P = 0.001) more likely than were controls to be sedentary. The homozygous variant for the APC gene (VV) was found in 4.6% of cases and in 3.5% of controls. Examination of the potential interactions between diet and genotype found that a high cholesterol intake was associated with a greater risk of colorectal cancer only in noncarriers (DD) of the D1822V APC allele (odds ratio: 1.66; 95% CI: 1.00, 2.76). In contrast, high fiber and calcium intakes were more markedly associated with a lower risk of CRC in patients carrying the polymorphic allele (DV/VV) (odds ratio: 0.50; 95% CI: 0.27, 0.94 for fiber; odds ratio: 0.51; 95% CI: 0.28, 0.93 for calcium) than in those without that allele. Conclusion - These results suggest a significant interaction between the D1822V polymorphism and the dietary intakes of cholesterol, calcium, and fiber for CRC risk

Improvement of DNA minicircle production by optimization of the secondary structure of the 5′-UTR of ParA resolvase

The use of minicircles in gene therapy applications is dependent on the availability of high-producer cell systems. In order to improve the performance of minicircle production in Escherichia coli by ParA resolvase-mediated in vivo recombination, we focus on the 5′ untranslated region (5′-UTR) of parA messenger RNA (mRNA). The arabinose-inducible P[subscript BAD]/araC promoter controls ParA expression and strains with improved arabinose uptake are used. The 27-nucleotide-long 5′-UTR of parA mRNA was optimized using a predictive thermodynamic model. An analysis of original and optimized mRNA subsequences predicted a decrease of 8.6–14.9 kcal/mol in the change in Gibbs free energy upon assembly of the 30S ribosome complex with the mRNA subsequences, indicating a more stable mRNA-rRNA complex and enabling a higher (48–817-fold) translation initiation rate. No effect of the 5′-UTR was detected when ParA was expressed from a low-copy number plasmid (∼14 copies/cell), with full recombination obtained within 2 h. However, when the parA gene was inserted in the bacterial chromosome, a faster and more effective recombination was obtained with the optimized 5′-UTR. Interestingly, the amount of this transcript was 2.6–3-fold higher when compared with the transcript generated from the original sequence, highlighting that 5′-UTR affects the level of the transcript. A Western blot analysis confirmed that E. coli synthesized higher amounts of ParA with the new 5′-UTR (∼1.8 ± 0.7-fold). Overall, these results show that the improvements made in the 5′-UTR can lead to a more efficient translation and hence to faster and more efficient minicircle generation.MIT-Portugal ProgramFundação para a Ciência e a Tecnologia (PhD grant SFRH/BD/33786/2009