Partial replacement of chemical fertilizers with animal manures in an apple orchard: Effects on crop performance and soil fertility

The combined use of chemical fertilisers with organic materials in crop fertilization is an essential approach to transition towards a more sustainable and resilient agriculture in Europe. In an apple orchard, chemical fertilisers (CF) were partially (25 to 57%) replaced with animal manure (cattle slurry - CS, acidified cattle slurry - ACS, cattle solid manure - CsM, and poultry manure - PM), based on the crop’s nitrogen (N) requirements. Apple production and soil properties were monitored during a 3-year experiment. At the end of the third year, leaf N was higher in the control treatment (CTRL, 100% CF). Apple production was, on average, higher in the CS treatment, although not significantly different from the CTRL. Fruit analysis showed that replacing CF with animal manures did not significantly impacted fruit quality (weight, ºBrix and firmness). Soil organic carbon (SOC), N and exchangeable potassium (K+) were significantly higher in the manure treatments. The increase in soil K+ in the manure treatments consequently increased soil K/magnesium (Mg) ratio, slightly mitigating K and Mg antagonism, as seen by the increase in fruit K. However, K content was still deficient in fruits and leaves in all treatments. It can be concluded that the partial replacement of chemical fertilisers by animal manures (CS, ACS and PM) had a positive effect on soil health with no decrease of apple production.info:eu-repo/semantics/publishedVersio

Nitrogen and Phosphorus Rates’ Impact on Different Varieties of Alfalfa in Central Kansas

The United States is the largest producer of alfalfa (Medicago sativaL.) in the world, with a vast area grown under rainfed conditions. Under these conditions, and especially in a transition state such as Kansas, the alfalfa crop often suffers from water deficit stress. Environments under water-limited conditions promote a decrease in crop yield when inadequate water leads to an nitrogen deficiency and reduces crop biomass. This research aimed to investigate the production of different alfalfa varieties under different nitrogen and phosphorus rates in a rainfed environment. Three nitrogen application rates (0 lb/a; 200 lb/a; 400 lb/a) and three phosphorus application rates (0 lb/a; 100 lb/a; and 200 lb/a) provided nine combinations of application rates to four alfalfa varieties (54HVX41, Pioneer 54VR10, LOL 356HQRR, and DKA43-22RR). Five harvests were executed at 10% of flowering, and the whole plant biomass was collected to determine the dry matter in ton/a. Despite the statistically significant results of treatment interaction, there was no pattern in the average values of alfalfa production among different treatments and seasons. The collected weather data provided empirical evidence to support that precipitation and evapotranspiration (specifically under water stress) influenced alfalfa yield. The four genotypes used in this field study tended to be stable in their yield in response to fertilization

A new cyanobacterial species with a protective effect on lettuce grown under salinity stress: envisaging sustainable agriculture practices

In this work, a new terrestrial cyanobacterial species, Oculatella lusitanica LEGE 161147, was isolated and characterized using a polyphasic approach. Morphologically, O. lusitanica shares characteristics with different Oculatella species (mainly with O. crustae-formantes), lacking distinctive features. However, the phylogeny based on the 16S rRNA gene sequence and the 16S-23S ITS secondary structures support the establishment of this isolate as a new species. O. lusitanica is placed within a clade mainly composed by other Oculatella terrestrial strains; however, it forms a separate lineage. In addition, our species differs from the other Oculatella described so far by lacking the V2 helix within the ITS region. Since cyanobacteria are known to release compounds that promote plant growth and/or increase their tolerance to stresses, the effect of this newly described cyanobacterial species on Lactuca sativa (lettuce) plants development and salinity stress resistance was evaluated. Our results showed that, although the cyanobacterium had no impact on plant growth under the conditions tested, it was able to mitigate the deleterious salinity stress effects on plant size, root and aerial part fresh weight, by eliciting the non-enzymatic antioxidant response system (proline, H2O2 and reduced glutathione). In addition, the microorganism was able to induce a priming effect on lettuce plants by stimulating defensive mechanisms under non-stress conditions, and enhances the activity of nitrogen metabolism-related enzymes glutamate dehydrogenase, glutamine synthetase and nitrate reductase. These results indicate that this native terrestrial cyanobacterial species could be employed as a tool in sustainable agricultural practices.This work was funded by National Funds through FCT—Fundação para a Ciência e a Tecnologia, I.P., under the projects PCIF/RPG/0077/2017, UIDB/04293/2020, UIDP/04293/2020, UIDB/05748/2020 and UIDP/05748/2020. This work was also funded by the FCT grant SFRH/BPD/115571/2016 (to AB) and LTAUSA 18008 (to JK)info:eu-repo/semantics/publishedVersio

The carboxylic acid transporters Jen1 and Jen2 affect the architecture and fluconazole susceptibility of Candida albicans biofilm in the presence of lactate

Candida albicans has the ability to adapt to different host niches, often glucose-limited but rich in alternative carbon sources. In these glucose-poor microenvironments, this pathogen expresses JEN1 and JEN2 genes, encoding carboxylate transporters, which are important in the early stages of infection. This work investigated how host microenvironments, in particular acidic containing lactic acid, affect C. albicans biofilm formation and antifungal drug resistance. Multiple components of the extracellular matrix were also analysed, including their impact on antifungal drug resistance, and the involvement of both Jen1 and Jen2 in this process. The results show that growth on lactate affects biofilm formation, morphology and susceptibility to fluconazole and that both Jen1 and Jen2 might play a role in these processes. These results support the view that the adaptation of Candida cells to the carbon source present in the host niches affects their pathogenicity.This study was funded by the Portuguese Foundation for Science and Technology (FCT) [grant number PTDC/BIAMIC/5184/2014]. SM, CFR and RA received FCT PhD studentships [grant numbers SFRH/BD/74790/2010, SFRH/ BD/93078/2013, PD/BD/113813/2015, respectively]. The work on CBMA was supported by FCT [grant number UID/ BIA/04050/2013] and COMPETE 2020 [grant number POCI01-0145-FEDER-007569]. The work on CEB was supported by FCT [grant number UID/BIO/04469/2013], COMPETE 2020 [grant number POCI-01-0145-FEDER-006684] and BioTecNorte operation [grant number NORTE-01-0145FEDER-000004] funded by the ERDF under the scope of Norte2020 – Programa Operacional Regional do Norte. AJPB was funded by the UK Medical Research Council [grant number MR/M026663/1]; by the UK Biotechnology and Biological Research Council [grant number BB/K017365/1]; and by the MRC Centre for Medical Mycology and the University of Aberdeen [grant number MR/M026663/1]. The funders had no role in study design, data collection and analysis, the decision to publish, or in the preparation of the manuscript.info:eu-repo/semantics/publishedVersio

Casimir Effect in E3E^3 closed spaces

As it is well known the topology of space is not totally determined by Einstein's equations. It is considered a massless scalar quantum field in a static Euclidean space of dimension 3. The expectation value for the energy density in all compact orientable Euclidean 3-spaces are obtained in this work as a finite summation of Epstein type zeta functions. The Casimir energy density for these particular manifolds is independent of the type of coupling with curvature. A numerical plot of the result inside each Dirichlet region is obtained.Comment: Version accepted for publication. The most general coupling with curvature is chose

Comparison of zinc oxide nanoparticle integration into non-woven fabrics using different functionalisation methods for prospective application as active facemasks

The development of advanced facemasks stands out as a paramount priority in enhancing healthcare preparedness. In this work, different polypropylene non-woven fabrics (NWF) were characterised regarding their structural, physicochemical and comfort-related properties. The selected NWF for the intermediate layer was functionalised with zinc oxide nanoparticles (ZnO NPs) 0.3 and 1.2wt% using three different methods: electrospinning, dip-pad-dry and exhaustion. After the confirmation of ZnO NP content and distribution within the textile fibres by morphological and chemical analysis, the samples were evaluated regarding their antimicrobial properties. The functionalised fabrics obtained via dip-pad-dry unveiled the most promising data, with 0.017 ± 0.013wt% ZnO NPs being mostly located at the fibre’s surface and capable of total eradication of Staphylococcus aureus and Escherichia coli colonies within the tested 24 h (ISO 22196 standard), as well as significantly contributing (**** p < 0.0001) to the growth inhibition of the bacteriophage MS2, a surrogate of the SARS-CoV-2 virus (ISO 18184 standard). A three-layered structure was assembled and thermoformed to obtain facemasks combining the previously chosen NWF, and its resulting antimicrobial capacity, filtration efficiency and breathability (NP EN ISO 149) were assessed. The developed three-layered and multiscaled fibrous structures with antimicrobial capacities hold immense potential as active individual protection facemasks.FCT -Fundação para a Ciência e a Tecnologia(LA/P/0029/2020)info:eu-repo/semantics/publishedVersio

A commercial blend of macroalgae and microalgae promotes digestibility, growth performance, and muscle nutritional value of European seabass (Dicentrarchus labrax L.) juveniles

Algae can leverage aquaculture sustainability and improve the nutritional and functional value of fish for human consumption, but may pose challenges to carnivorous fish. This study aimed to evaluate the potential of a commercial blend of macroalgae (Ulva sp. and Gracilaria gracilis) and microalgae (Chlorella vulgaris and Nannochloropsis oceanica) in a plant-based diet up to 6% (dry matter basis) on digestibility, gut integrity, nutrient utilization, growth performance, and muscle nutritional value of European seabass juveniles. Fish (11.3 ± 2.70 g) were fed with isoproteic, isolipidic, and isoenergetic diets: (i) a commercial-type plant-based diet with moderate fishmeal (125 g kg−1 DM basis) and without algae blend (control diet; Algae0), (ii) the control diet with 2% algae blend (Algae2), (iii) the control diet with 4% algae blend (Algae4), and (iv) the control diet with 6% algae blend (Algae6) for 12 weeks. The digestibility of experimental diets was assessed in a parallel study after 20 days. Results showed that most nutrients and energy apparent digestibility coefficients were promoted by algae blend supplementation, with a concomitant increase in lipid and energy retention efficiencies. Growth performance was significantly promoted by the algae blend, the final body weight of fish fed Algae6 being 70% higher than that of fish fed Algae0 after 12 weeks, reflecting up to 20% higher feed intake of algae-fed fish and the enhanced anterior intestinal absorption area (up to 45%). Whole-body and muscle lipid contents were increased with dietary algae supplementation levels by up to 1.79 and 1.74 folds in Algae 6 compared to Algae0, respectively. Even though the proportion of polyunsaturated fatty acids was reduced, the content of EPA and DHA in the muscle of algae-fed fish increased by nearly 43% compared to Algae0. The skin and filet color of juvenile European seabass were significantly affected by the dietary inclusion of the algae blend, but changes were small in the case of muscle, meeting the preference of consumers. Overall results highlight the beneficial effects of the commercial algae blend (Algaessence®) supplementation in plant-based diets for European seabass juveniles, but feeding trials up to commercial-size fish are needed to fully assess its potential

Generation of transgenic rodent malaria parasites by transfection of cell culture-derived merozoites

Malaria research is greatly dependent on and has drastically advanced with the possibility of genetically modifying Plasmodium parasites. The commonly used transfection protocol by Janse and colleagues utilizes blood stage-derived Plasmodium berghei schizonts that have been purified from a blood culture by density gradient centrifugation. Naturally, this transfection protocol depends on the availability of suitably infected mice, constituting a time-based variable. In this study, the potential of transfecting liver stage-derived merozoites was explored. In cell culture, upon merozoite development, infected cells detach from the neighbouring cells and can be easily harvested from the cell culture supernatant. This protocol offers robust experimental timing and temporal flexibility. HeLa cells are infected with P. berghei sporozoites to obtain liver stage-derived merozoites, which are harvested from the cell culture supernatant and are transfected using the Amaxa Nucleofector(®) electroporation technology. Using this protocol, wild type P. berghei ANKA strain and marker-free PbmCherryHsp70-expressing P. berghei parasites were successfully transfected with DNA constructs designed for integration via single- or double-crossover homologous recombination. An alternative protocol for Plasmodium transfection is hereby provided, which uses liver stage-derived P. berghei merozoites for transfection. This protocol has the potential to substantially reduce the number of mice used per transfection, as well as to increase the temporal flexibility and robustness of performing transfections, if mosquitoes are routinely present in the laboratory. Transfection of liver stage-derived P. berghei parasites should enable generation of transgenic parasites within 8-18 days