The effects of the use of organic solid wastes on the growth of citrus trees

Two types of organic solid wastes were selected to be applied in a citrus orchard: the sewage sludge (the most common on the settlements) and the manure (the most common on the agricultural fields). The sewage sludge is a residue originated from the wastewater treatment - the solid phase. Its application as an organic fertilizer may represent an alternative to the pollution effects in nature. In an orchard of orange-trees (Citrus sinensis [L.] Osbeck), the application of sludge was compared with the application of manure and with the control in order to observe the growth response of the trees. Biometric methods where used - number of leaves per tree, diameter of the trunk, leaf area, specific leaf areas and leaf chlorophyll content. In general, the citrus plants response to the application of sewage sludge and manure was positive for the plant growth, compared to the control. The application of the manure, and especially the sewage sludge (once this fertilizer / soil amendment is available in larger amounts) may be a profitable alternative application to the use of mineral fertilizers and to other soil amendments. Moreover, as the possible destinations of sewage sludge (sea, deposition in land fields, incineration) provoke environmental problems, its agricultural reuse is essential to avoid those problems, when correctly applied in relation to trace elements and to pathogenic parameters. The reuse of this solid waste may be a clean and a safe technique to preserve the environment contamination

Characterization of smart MARFOS NiTi shape memory alloys

In the present study, structural characterization of NiTi smart shape memory al-loys (SMAs), produced by an alternative powder metallurgy approach named mechanically ac-tivated reactive forging (MARFOS), was carried out by means of transmission electron micros-copy (TEM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). It was observed that MARFOS materials had a multiphase nanocrystalline structure. In addition, the transformation behaviour associated with the shape memory effect of the MARFOS aged mate-rials was studied with differential scanning calorimetry (DSC). Multiple-step martensitic trans-formations could be observed in aged materials

Nonconventional production technologies for NiTi shape memory alloys

The development of new production technologies for NiTi Shape Memory Alloys (SMAs) is always challenging. Recently, we introduced two powder metallurgical (PM) processing routes involving mechanical activation of elemental powder mixtures and densification through extrusion or forging. Those processes were named Mechanically Activated Reactive Extrusion Synthesis (MARES) and Mechanically Activated Reactive FOrging Synthesis (MARFOS). Heat treatments were performed in order to adjust the B2-NiTi matrix composition, yielding a microstructure consisting of a homogeneous dispersion of Ni4Ti3 precipitates embedded in nanocrystalline B2-NiTi matrix. In the present study, we demonstrate the viability of those PM processes for producing NiTi SMAs. With insitu X-ray diffraction and differential scanning calorimetry it is shown that B2-NiTi matrix undergo a B2« R«B19 two-step phase transformatio

Mechanical activation of pre-alloyed NiTi2 and elemental Ni for the synthesis of NiTi alloys

ABSTRACT: This work reports on an efficient powder metallurgy method for the synthesis of NiTi alloys, involving mechanical activation of pre-alloyed NiTi2 and elemental Ni powders (NiTi2-Ni) followed by a press-and-sinter step. The idea is to take advantage of the brittle nature of NiTi2 to promote a better efficiency of the mechanical activation process. The conventional mechanical activation route using elemental Ti and Ni powders (Ti-Ni) was also used for comparative purposes. Starting with (NiTi2-Ni) powder mixtures resulted in the formation of a predominant amorphous structure after mechanical activation at 300 rpm for 2 h. A sintered specimen consisting mainly of NiTi phase was obtained after vacuum sintering at 1050 degrees C for 0.5 h. The produced NiTi phase exhibited the martensitic transformation behavior. Using elemental Ti powders instead of pre-alloyed NiTi2 powders, the structural homogenization of the synthesized NiTi alloys was delayed. Performing the mechanical activation at 300 rpm for the (Ti-Ni) powder mixtures gave rise to the formation of composite particles consisting in dense areas of alternate fine layers of Ni and Ti. However, no significant structural modification was observed even after 16 h of mechanical activation. Only after vacuum sintering at 1050 degrees C for 6 h, the NiTi phase was observed to be the predominant phase. The higher reactivity of the mechanically activated (NiTi2-Ni) powder particles can explain the different sintering behavior of those powders compared with the mechanically activated (Ti-Ni) powders. It is demonstrated that this innovative approach allows an effective time reduction in the mechanical activation and of the vacuum sintering step.info:eu-repo/semantics/publishedVersio

Photoluminescence studies of a perceived white light emission from a monolithic InGaN/GaN quantum well structure

In this work we demonstrate by photoluminescence studies white light emission from a monolithic InGaN/GaN single quantum well structure grown by metal organic chemical vapour deposition. As-grown and thermally annealed samples at high temperature (1000 °C, 1100 °C and 1200 °C) and high pressure (1.1 GPa) were analysed by spectroscopic techniques, and the annealing effect on the photoluminescence is deeply explored. Under laser excitation of 3.8 eV at room temperature, the as-grown structure exhibits two main emission bands: a yellow band peaked at 2.14 eV and a blue band peaked at 2.8 eV resulting in white light perception. Interestingly, the stability of the white light is preserved after annealing at the lowest temperature (1000 °C), but suppressed for higher temperatures due to a deterioration of the blue quantum well emission. Moreover, the control of the yellow/blue bands intensity ratio, responsible for the white colour coordinate temperatures, could be achieved after annealing at 1000 °C. The room temperature white emission is studied as a function of incident power density, and the correlated colour temperature values are found to be in the warm white range: 3260–4000 K

Determination of the parameters affecting electrospun chitosan fiber size distribution and morphology

The production of chitosan nanofiber mats by electrospinning presents serious difficulties due to the lack of suitable solvents and the strong influence of processing parameters on the fiber properties. Two are the main problems to be solved: to control the properties of the solution in order to obtain large area uniform fiber mats by having a stable flow rate and to avoid sparks during the process, damaging the fiber mats. In this work chitosan electrospun mats have been prepared form solutions of trifluoroacetic acid / dichloromethane mixtures, allowing to solve the aforementioned problems. Mats with uniform fibers of submicron diameters without beads were obtained. Further, the influence of the different solution and process parameters on the mean fiber diameter and on the width of the distribution of the fiber sizes has been assessed. Solvent composition, needle diameter, applied voltage and traveling distance were the parameters considered in this study.This work is funded by FEDER funds through the "Programa Operacional Factores de Competitividade – COMPETE" and by national funds by FCT- Fundação para a Ciência e a Tecnologia, project references NANO/NMed-SD/0156/2007. V.S. thanks the FCT for the SFRH/BPD/63148/2009 grants. JLGR acknowledge the support of the Spanish Ministry of Science and Innovation through project No. MAT2010-21611-C03-01 (including the FEDER financial support) and Programa Nacional de Internacionalización de la I+D project EUI2008-00126. Funding for research in the field of Regenerative Medicine through the collaboration agreement from the Conselleria de Sanidad (Generalitat Valenciana), and the Instituto de Salud Carlos III (Ministry of Science and Innovation) is also acknowledged

Antifouling Marine Coatings with a Potentially Safer and Sustainable Synthetic Polyphenolic Derivative

The development of harmless substances to replace biocide-based coatings used to prevent or manage marine biofouling and its unwanted consequences is urgent. The formation of biofilms on submerged marine surfaces is one of the first steps in the marine biofouling process, which facilitates the further settlement of macrofoulers. Anti-biofilm properties of a synthetic polyphenolic compound, with previously described anti-settlement activity against macrofoulers, were explored in this work. In solution this new compound was able to prevent biofilm formation and reduce a pre-formed biofilm produced by the marine bacterium, Pseudoalteromonas tunicata. Then, this compound was applied to a marine coating and the formation of P. tunicata biofilms was assessed under hydrodynamic conditions to mimic the marine environment. For this purpose, polyurethane (PU)-based coating formulations containing 1 and 2 wt.% of the compound were prepared based on a prior developed methodology. The most effective formulation in reducing the biofilm cell number, biovolume, and thickness was the PU-based coating containing an aziridine-based crosslinker and 2 wt.% of the compound. To assess the marine ecotoxicity impact of this compound, its potential to disrupt endocrine processes was evaluated through the modulation of two nuclear receptors (NRs), peroxisome proliferator-activated receptor gamma (PPAR gamma), and pregnane X receptor (PXR). Transcriptional activation of the selected NRs upon exposure to the polyphenolic compound (10 mu M) was not observed, thus highlighting the eco-friendliness towards the addressed NRs of this new dual-acting anti-macro- and anti-microfouling agent towards the addressed NRs

EGF functionalized polymer-coated gold nanoparticles promote EGF photostability and EGFR internalization for photothermal therapy

The application of functionalized nanocarriers on photothermal therapy for cancer ablation has wide interest. The success of this application depends on the therapeutic efficiency and biocompatibility of the system, but also on the stability and biorecognition of the conjugated protein. This study aims at investigating the hypothesis that EGF functionalized polymer -coated gold nanoparticles promote EGF photostability and EGFR internalization, making these conjugated particles suitable for photothermal therapy. The conjugated gold nanoparticles (100-200 nm) showed a plasmon absorption band located within the near infrared range (650-900 nm), optimal for photothermal therapy applications. The effects of temperature, of polymer-coated gold nanoparticles and of UVB light (295nm) on the fluorescence properties of EGF have been investigated with steady-state and time-resolved fluorescence spectroscopy. The fluorescence properties of EGF, including the formation of Trp and Tyr photoproducts, is modulated by temperature and by the intensity of the excitation light. The presence of polymeric-coated gold nanoparticles reduced or even avoided the formation of Trp and Tyr photoproducts when EGF is exposed to UVB light, protecting this way the structure and function of EGF. Cytotoxicity studies of conjugated nanoparticles carried out in normal-like human keratinocytes showed small, concentration dependent decreases in cell viability (0-25%). Moreover, conjugated nanoparticles could activate and induce the internalization of overexpressed Epidermal Growth Factor Receptor in human lung carcinoma cells. In conclusion, the gold nanoparticles conjugated with Epidermal Growth Factor and coated with biopolymers developed in this work, show a potential application for near infrared photothermal therapy, which may efficiently destroy solid tumours, reducing the damage of the healthy tissue.Support was provided by: Fundacao para a Ciencia e Tecnologia (FCT) for the financial support under the project reference PTDC/BBB-BMC/0611/2012 [https://www.fct.pt/apoios/projectos)]. The work at CBMA was supported by the strategic programme UID/BIA/04050/2013 (POCI-01-0145-FEDER-007569) funded by national funds through the FCT I.P. and by the ERDF through the COMPETE2020 - Programa Operacional Competitividade e Internacionalizacao (POCI) [https://www.fct.pt/apoios/projectos]; European Commission through the project H2020-644242-SAPHELY (https://saphely.eu/project.php) and the project H2020-634013-2-PHOCNOSIS [http://cordis.europa.eu/project/rcn/193268_en.html].The authors would like to thank Fundacao para a Ciencia e Tecnologia (FCT) for the financial support under the project reference PTDC/BBB-BMC/0611/2012. The work at CBMA was supported by the strategic programme UID/BIA/04050/2013 (POCI-01-0145-FEDER-007569) funded by national funds through the FCT I.P. and by the ERDF through the COMPETE2020 - Programa Operacional Competitividade e Internacionalizacao (POCI). The authors acknowledge the funding from the European Commission through the project H2020-644242-SAPHELY and the project H2020-634013-2-PHOCNOSIS. Finally, the authors would also like to thank the master student Joao Lopes from Universidade Lusofona (Portugal) for the help with in vitro cytotoxic assays. Isabel Correia acknowledges FCT for Investigator FCT contract.info:eu-repo/semantics/publishedVersio

Late Onset Neuromyelitis Optica Spectrum Disorders (LONMOSD) from a Nationwide Portuguese Study: Anti-AQP4 Positive, Anti-MOG Positive and Seronegative Subgroups

Introduction: Several neuroimmunological disorders have distinct phenotypes according to the age of onset, as in multiple sclerosis or myasthenia gravis. It is also described that late onset NMOSD (LONMOSD) has a different phenotype. Objective: To describe the clinical/demographic characteristics of the LONMOSD and distinguish them from those with early onset (EONMOSD). Methods: From a nationwide Portuguese NMOSD study we analyzed the clinical/demographic characteristics of the LONMOSD. Results: From the 180 Portuguese patients 45 had disease onset after 50 years old, 80% were female. 23 had anti-AQP4 antibodies (51.1%), 13 anti-MOG antibodies (28.9%) and 9 were double seronegative (20.0%). The most common presenting phenotypes in LONMOSD were transverse myelitis (53.3%) and optic neuritis (26.7%), without difference from EONMOSD (p = 0.074). The mean EDSS for LONMOSD was 6.0 (SD=2.8), after a mean follow-up time of 4.58 (SD=4.47) years, which was significantly greater than the mean EDSS of EONMOSD (3.25, SD=1.80)(p = 0.022). Anti-AQP4 antibodies positive LONMOSD patients had increased disability compared to anti-MOG antibodies positive LONMOSD (p = 0.022). The survival analysis showed a reduced time to use a cane for LONMOSD, irrespective of serostatus (p<0.001). Conclusions: LONMOSD has increased disability and faster progression, despite no differences in the presenting clinical phenotype were seen in our cohort.info:eu-repo/semantics/publishedVersio