Monte Carlo Radiative Transfer Modeling of Underwater Channel

The radiative transfer equation (RTE) is a theoretical framework that can be used for predicting and interpreting underwater light fields in terms of the constituents of natural water bodies. However, the RTE is a complex integrodifferential equation and deriving exact solutions for it is a difficult task. In this chapter, we aim to present some details regarding Monte Carlo simulations and how this method may be applied to solve the RTE numerically. By solving the RTE, one may accurately predict the received power and estimate the channel bandwidth and several other measurable parameters with regard to multiple water conditions. Simulations will also be presented

OFDM and SC-FDMA over Fiber Using Directly Modulated VCSELs

Radio-over-fiber technology, used in the transport of radio signals over optical fiber by means of an optical carrier between a remote site and a central node of a cellular network, is an attractive solution for backhauling of a large number of remote antennas, enabling the shifting of the hardware complexity from base stations to a central station

A novel VIVO–pyrimidinone complex: synthesis, solution speciation and human serum protein binding

The pyrimidinones mhcpe, 2-methyl-3H-5-hydroxy-6-carboxy-4-pyrimidinone ethyl ester (mhcpe, 1), 2,3- dimethyl-5-benzyloxy-6-carboxy-4-pyrimidinone ethyl ester (dbcpe, 2) and N-methyl-2,3-dimethyl-5- hydroxy-6-carboxyamido-4-pyrimidinone (N-MeHOPY, 3), are synthesized and their structures determined by single crystal X-ray diffraction. The acid–base properties of 1 are studied by potentiometric and spectrophotometric methods, the pKa values being 1.14 and 6.35. DFT calculations were carried out to determine the most stable structure for each of the H2L+, HL and L− forms (HL = mhcpe) and assign the groups involved in the protonation–deprotonation processes. The mhcpe− ligand forms stable complexes with VIVO2+ in the pH range 2 to 10, and potentiometry, EPR and UV-Vis techniques are used to identify and characterize the VIVO–mhcpe species formed. The results are consistent with the formation of VIVO, (VIVO)L, (VIVO)L2, (VIVO)2L2H−2, (VIVO)L2H−1, (VIVO)2L2H−3, (VIVO)LH−2 species and VIVO-hydrolysis products. Calculations indicate that the global binding ability of mhcpe towards VIVO2+ is similar to that of maltol (Hmaltol = 3-hydroxy-2-methyl-4H-pyran-4-one) and lower than that of 1,2-dimethyl-3-hydroxy-4- pyridinone (Hdhp). The interaction of VIVO-complexes with human plasma proteins (transferrin and albumin) is studied by circular dichroism (CD), EPR and 51V NMR spectroscopy. VIVO–mhcpe–protein ternary complexes are formed in both cases. The binding of VIVO2+ to transferrin (hTF) in the presence of mhcpe involves mainly (VIVO)1(hTF)(mhcpe)1, (VIVO)2(hTF)(mhcpe)1 and (VIVO)2(hTF)(mhcpe)2 species, bound at the FeIII binding sites, and the corresponding conditional formation constants are determined. Under the conditions expected to prevail in human blood serum, CD data indicate that the VIVO–mhcpe complexes mainly bind to hTF; the formation of VIVO–hTF–mhcpe complexes occurs in the presence of FeIII as well, distinct EPR signals being clearly obtained for FeIII–hTF and to VIVO–hTF–mhcpe species. Thus this study indicates that transferrin plays the major role in the transport of VIVO–mhcpe complexes under blood plasma conditions in the form of ternary VIV–ligand–protein complexes.The authors are grateful to the Fundo Europeu para o Desenvolvimento Regional, Fundação para a Ciência e Tecnologia (FCT), the POCI 2010 Programme, the Portuguese NMR Network (IST-UTL Center), PEst-OE/QUI/UI0100/2011, University of A Coruña and the Spanish-Portuguese Bilateral Programme (Acção Integrada E-56/05, Acción integrada HP2004- 0074)

Calcium biofortification of Rocha pears, tissues accumulation and physicochemical implications in fresh and heat-treated fruits

Low dietary intake of Ca in humans has been epidemiologically linked to various diseases, which can have serious health consequences over time. Accordingly, the development of an agronomic itinerary for Ca biofortification of Rocha pears and the assessment of physicochemical deviations prompted this study. Two orchards with contrasting soil and water characteristics were selected, characterized through orthophotomaping and, during fruits development, leaves were sprayed twice with Ca(NO3)2 (0.1, 0.3 and 0.6 kg ha - 1) or CaCl2 (0.4, 0.8 and 1.6 kg ha - 1), followed by pulverization only with CaCl2 (first once with 4 kg ha - 1 and then four times with 8 kg ha - 1). During fruits development net photosynthesis, stomatal conductance, transpiration rates, instantaneous and water use efficiency, only showed minor deviations, which indicated that the threshold of toxicity was not surpassed. Calcium contents varied during fruits development and at harvesting the average biofortification index varied between 47 %–63 % and 24 %–59 % in each of the orchards. Besides, the equatorial region of the fruits showed for all treatments (substantially in Ca treated samples) higher Ca contents in the epidermal and in the central regions. Fresh and heat-treated fruits (in a thermomix at 90 ◦C, during 10 min) biofortified with Ca only revealed minor differences and the sensory acceptability did not vary markedly. It is concluded that, although prevailing a heterogeneous distribution of Ca in fruit tissues, high indexes of biofortification in Rocha pears can be prompt in the orchards, without substantial physicochemical changes. Accordingly, agronomic biofortification with Ca can be used as a strategy for benefiting consumer’s healthinfo:eu-repo/semantics/publishedVersio

Implications for Quality and Wine Production

UID/FIS/04559/2020Nowadays, there is a growing concern about micronutrient deficits in food products, with agronomic biofortification being considered a mitigation strategy. In this context, as Zn is essential for growth and maintenance of human health, a workflow for the biofortification of grapes from the Vitis vinifera variety Fernão Pires, which contains this nutrient, was carried out considering the soil properties of the vineyard. Additionally, Zn accumulation in the tissues of the grapes and the implications for some quality parameters and on winemaking were assessed. Vines were sprayed three times with ZnO and ZnSO4 at concentrations of 150, 450, and 900 g ha−1 during the production cycle. Physiological data were obtained through chlorophyll a fluorescence data, to access the potential symptoms of toxicity. At harvest, treated grapes revealed significant increases of Zn concentration relative to the control, being more pronounced for ZnO and ZnSO4 in the skin and seeds, respectively. After winemaking, an increase was also found regarding the control (i.e., 1.59-fold with ZnSO4-450 g ha−1). The contents of the sugars and fatty acids, as well as the colorimetric analyses, were also assessed, but significant variations were not found among treatments. In general, Zn biofortification increased with ZnO and ZnSO4, without significantly affecting the physicochemical characteristics of grapes.publishersversionpublishe

Size effects on antimicrobial efficiency of DBD plasma coated silver nanoparticles on textiles

This work studies the surface characteristics, the antimicrobial activity and the aging effect, of plasma pre-treated polyamide 6,6 fabrics (PA66) coated with silver nanoparticles (AgNPs), with the aim to identify the optimum size of nanosilver exhibiting antibacterial properties suitable for manufacturing of hospital textiles. The release of bactericidal Ag+ ions from the 10, 20, 40, 60 and 100 nm AgNPs-coated PA66 surface were function of the particles size, number and aging. Plasma pre-treatment promoted both ionic and covalent interactions between AgNPs and the formed oxygen species on the fibers (Figure 1), favoring the deposition of smaller in diameter AgNPs that consequently showed better immediate and durable antimicrobial effect against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus bacteria. Surprisingly, after 30 days of aging, a comparable bacterial growth inhibition was achieved for all the fibers treated with AgNPs of <100 nm in size. The Ag+ in the coatings also favored the electrostatic stabilization of the plasma-induced functional groups on the PA66 surface, thereby retarding the aging process (Figure 2). At the same time, the size-related ratio Ag+/Ag0 of the AgNPs between 40 and 60 nm allowed for controlled release of Ag+ rather than bulk silver. Overall, the results suggest that instead of reducing the AgNPs size, which is associated to higher toxicity, similar long-term effects can be achieved with larger NPs (40-60 nm), even in lower concentrations. Since the antimicrobial efficiency of AgNPs larger than 30 nm is mainly ruled by the release of Ag+ over time and not by the size and number of the AgNPs, this parameter is crucial for the development of efficient antimicrobial coatings on plasma-treated surfaces, and contribution to the safety and durability of clothing used in clinical settings

Fed-Batch Production of Saccharomyces cerevisiae L-Asparaginase II by Recombinant Pichia pastoris MUTs Strain

L-Asparaginase (ASNase) is used in the treatment of acute lymphoblastic leukemia, being produced and commercialized only from bacterial sources. Alternative Saccharomyces cerevisiae ASNase II coded by the ASP3 gene was biosynthesized by recombinant Pichia pastoris MUTs under the control of the AOX1 promoter, using different cultivation strategies. In particular, we applied multistage fed-batch cultivation divided in four distinct phases to produce ASNase II and determine the fermentation parameters, namely specific growth rate, biomass yield, and enzyme activity. Cultivation of recombinant P. pastoris under favorable conditions in a modified defined medium ensured a dry biomass concentration of 31 gdcw.L−1 during glycerol batch phase, corresponding to a biomass yield of 0.77 gdcw.gglycerol-1 and a specific growth rate of 0.21 h−1. After 12 h of glycerol feeding under limiting conditions, cell concentration achieved 65 gdcw.L−1 while ethanol concentration was very low. During the phase of methanol induction, biomass concentration achieved 91 gdcw.L−1, periplasmic specific enzyme activity 37.1 U.gdcw-1, volumetric enzyme activity 3,315 U.L−1, overall enzyme volumetric productivity 31 U.L−1.h−1, while the specific growth rate fell to 0.039 h−1. Our results showed that the best strategy employed for the ASNase II production was using glycerol fed-batch phase with pseudo exponential feeding plus induction with continuous methanol feeding

Size and aging effects on antimicrobial efficiency of silver nanoparticles coated on polyamide fabrics activated by atmospheric DBD plasma

Recently, renewed interest has arisen in silver nanopar@cles for biomedical devices because of their high surface energy, enhanced physicochemical and biological proper@es and extremely large surface area, which provides beAer contact with microorganisms. Atmospheric plasma is an alterna@ve and cost- compe@@ve method to wet chemical nanopar@cles deposi@on methods, avoiding the need of toxic solvents, expensive vacuum equipment and allowing con@nuous and uniform processing of material surfaces. However, there are no reports on the size and @me-dependent an@microbial, physical and chemical surface effects of the silver nanopar@cles immobilized on plasma func@onalized polymers. Thus, the purposes of this study were: (i) the silver nanopar@cle size and aging effects aCer 30 days on the an@microbial ac@vity aCer deposi@on onto DBD plasma-treated polyamide 6,6 fabrics, and (ii) the aging effect on the physico-chemical binding mechanism between different sized silver nanopar@cles and the plasma treaded polyamide 6,6. Five different in size commercial silver nanopar@cles have been employed (10, 20, 40 60 and 100 nm).This work was funded by Portuguese Founda@on for Science and Technology FCT/MCTES (PIDDAC) and co-financed by European funds (FEDER) through the PT2020 program, research project M-ERA-NET/0006/2014 and COMPETE program through FCT within the scope of the project POCI-01-0145-FEDER-007136 and UID/CTM/00264.info:eu-repo/semantics/publishedVersio

Influence of EPICardial adipose tissue in HEART diseases (EPICHEART) study: Protocol for a translational study in coronary atherosclerosis

Accumulation of epicardial adipose tissue (EAT) is associated with coronary artery disease (CAD) and increased risk of coronary events in asymptomatic subjects and low-risk patients, suggesting that EAT promotes atherosclerosis in its early stage. Recent studies have shown that the presence of CAD affects the properties of adjacent EAT, leading to dynamic changes in the molecular players involved in the interplay between EAT and the coronary arteries over the history of the disease. The role of EAT in late-stage CAD has not been investigated.coronárioResumoIntroduc¸ão:Acumulac¸ão de tecido adiposo epicárdico (TAE) tem sido associado a doenc¸acoronária aterosclerótica (DC) e aumento do risco de eventos coronários em indivíduos ass-intomáticos e doentes de baixo risco, sugerindo que o TAE pode promover fases precoces daDC. Estudo recentes mostraram que a presenc¸a de DC afeta as características do TAE adja-cente levando a modificac¸ões dinâmicas nos mediadores envolvidos na comunicac¸ão entre oTAE e as artérias coronárias ao longo da história da DC. O papel doTAE nas fases avanc¸adas daaterosclerose coronária não foi investigado.Objetivos: Através de análise comparativa com o tecido adiposo mediastínico e subcutâneo,pretendemos investigar se o volume do TAE, avaliado por tomografia computadorizada (TC), eo seu proteoma, avaliado por espectrometria de massa técnica de SWATH, estão associados aestadios avanc¸ados da DC numa coorte de estenose aórtica grave.Métodos: O estudo EPICHEART (NCT03280433) é um estudo prospetivo que inclui doentescom estenose aórtica grave referenciados para substituic¸ão eletiva da válvula aórtica, cujoprotocolo envolve avaliac¸ão pré-operatória clínica, nutricional, ecocardiográfica, por TC eangiografia coronária invasiva. Durante a cirurgia cardíaca, colhemos amostras de tecido adi-poso epicárdico, mediastínico e subcutâneo para análise do seu proteoma por espectrometriade massa técnica de SWATH. Adicionalmente, colhemos líquido pericárdico, sangue venoso per-iférico e do seio coronário para investigar mediadores de DC derivados do TAE na circulac¸ãosistémica e local.Conclusão: Desenhámos um estudo de translac¸ão para explorar a associac¸ão da quantidade equalidade do TAE com a DC tardia. Esperamos identificar mediadores da comunicac¸ão recíprocaentre o TAE e as artérias coronárias que estão envolvidos na patogénese das fases avanc¸adas daDC, especialmente, calcificac¸ão coronária, os quais podem servir como novos alvos terapêuticose soluc¸ões de engenharia biomédica para visualizac¸ão da DC