985 research outputs found
Addition of a histone deacetylase inhibitor increases recombinant protein expression in Medicago truncatula cell cultures
Plant cell cultures are an attractive platform for the production of recombinant proteins. A major drawback, hindering the establishment of plant cell suspensions as an industrial platform, is the low product yield obtained thus far. Histone acetylation is associated with increased transcription levels, therefore it is expected that the use of histone deacetylase inhibitors would result in an increase in mRNA and protein levels. Here, this hypothesis was tested by adding a histone deacetylase inhibitor, suberanilohydroxamic acid (SAHA), to a cell line of the model legume Medicago truncatula expressing a recombinant human protein. Histone deacetylase inhibition by SAHA and histone acetylation levels were studied, and the effect of SAHA on gene expression and recombinant protein levels was assessed by digital PCR. SAHA addition effectively inhibited histone deacetylase activity resulting in increased histone acetylation. Higher levels of transgene expression and accumulation of the associated protein were observed. This is the first report describing histone deacetylase inhibitors as inducers of recombinant protein expression in plant cell suspensions as well as the use of digital PCR in these biological systems. This study paves the way for employing epigenetic strategies to improve the final yields of recombinant proteins produced by plant cell cultures.publishersversionpublishe
Gender Dynamics in a Masculine Professional Context: The Case of the Portuguese Air Force
This article aims to understand the experiences of women working in the Portuguese Air
Force, a traditionally male professional environment, and the perspectives of their male counterparts
on the subject, considering women’s minority status and symbolic gender asymmetries in the military.
This study draws on 16 semi-structured interviews with Air Force personnel, evenly split by gender.
Findings reveal four main themes that convey awareness that the Air Force is still a masculine world,
perceptions of gender dynamics in the Air Force, barriers to equality, and strategies to address the
situation. Although gender equality is formally in place in the Air Force, women continue to face
obstacles that hinder their career advancement and ensure that their professional experiences differ
from those of their male counterpartsinfo:eu-repo/semantics/publishedVersio
Superficial sedimentary stocks and sources of carbon and nitrogen in coastal vegetated assemblages along a flow gradient
Coastal vegetated ecosystems are major organic carbon (OC) and total nitrogen (TN) sinks, but the mechanisms that regulate their spatial variability need to be better understood. Here we assessed how superficial sedimentary OC and TN within intertidal vegetated assemblages (saltmarsh and seagrass) vary along a flow gradient, which is a major driver of sediment grain size, and thus of organic matter (OM) content. A significant relationship between flow current velocity and OC and TN stocks in the seagrass was found, but not in the saltmarsh. OC and TN stocks of the saltmarsh were larger than the seagrass, even though that habitat experiences shorter hydroperiods. Mixing models revealed that OM sources also varied along the flow gradient within the seagrass, but not in the saltmarsh, showing increasing contributions of microphytobenthos (17-32%) and decreasing contributions of POM (45-35%). As well, OM sources varied vertically as microphytobenthos contribution was highest at the higher intertidal saltmarsh (48%), but not POM (39%). Macroalgae, seagrass and saltmarsh showed low contributions. Local trade-offs between flow current velocities, hydroperiod and structural complexity of vegetation must be considered, at both horizontal and vertical (elevation) spatial dimensions, for better estimates of blue carbon and nitrogen in coastal ecosystems.Foundation of Science and Technology of Portugal (FCT)
PTDC/MAR-EST/3223/2014
UID/Multi/04326/2013
FCT UID/MAR/00350/2018
SFRH/BPD/119344/2016info:eu-repo/semantics/publishedVersio
Forced to Work from Home: Division of Unpaid Work between Parents and the Relation to Job Satisfaction
This study investigates the division of household chores and caregiving tasks during the COVID-19 pandemic, considering the influence of participants’ sex, work arrangement, and parental status. Additionally, it aims to understand the relationship of these variables with job satisfaction. Specifically, this study analyses the role of participants’ sex and parental status in the increase and division of unpaid work and investigates the roles of sex, work arrangements (namely telework and on-site work), and the division of unpaid work in job satisfaction. These variables were measured and analyzed with a sample of 268 workers in Portugal (57.8% of whom were teleworking) during pandemic lockdowns. Taken together, the results suggest that despite prepandemic advances in gender equality and despite men and women perceiving an increase in their domestic workload during lockdowns, there were significant inequalities between men and women in the division of unpaid work. These were intensified for couples with young children and were not mitigated by changes in work arrangements such as telework. For women, the lack of sharing in caregiving tasks while teleworking decreased their job satisfaction. For them, the lack of sharing of caregiving tasks moderates the relationship between work arrangements and job satisfaction. The same was not true for men. Despite the optimistic view that telework might promote a more equal sharing of unpaid work, this study shows that unpaid work is still mostly performed by women, with important consequences for the paid work sphere.info:eu-repo/semantics/publishedVersio
Vertical intertidal variation of organic matter stocks and patterns of sediment deposition in a mesotidal coastal wetland
Tidal coastal wetlands, common home to seagrass and salt marshes, are relevant carbon sinks due to their high
capacity to accumulate and store organic carbon in their sediments. Recent studies demonstrated that the spatial
variability of this organic carbon within the same wetland system can be significant. Some of the environmental
drivers of this spatial variability remain understudied and the selection of the most relevant ones can be context
dependent. Here we investigated the role of bed elevation, hydrodynamics, and habitat type (salt marsh and
seagrass) on the organic matter (OM) net deposition-resuspension rate and superficial sedimentary stocks (top 5
cm) at the tidal wetlands of the Ria Formosa, a mesotidal coastal lagoon in South Portugal. Results showed that
two vectors of spatial variation need to be considered to describe the intertidal sedimentary OM stocks: the bed
elevation that imposes a decrease of the hydroperiod and thus the change of habitat from the lower seagrass
Z. noltei to the upper saltmarsh S. maritimus, and the horizontal spatial variation along the secondary channels of
the lagoon that imposes a decrease in the current flow velocity magnitude. The multiple linear regression analyses, using data from 40 sampling points, explained 59% of the variation of the superficial sedimentary stocks
of OM in salt marshes and seagrasses of the Ria Formosa lagoon and revealed that stocks generally decrease with
elevation, yet with variation among sites and habitats. It was also found that the decrease of the OM net
deposition-resuspension rate with bed elevation was exponential. Our study emphasizes the importance of
considering multiple environmental drivers and spatial variation for regional estimations of organic matter (and
organic carbon) sedimentary stocks in coastal wetlands.info:eu-repo/semantics/publishedVersio
Carbon and nitrogen stocks and burial rates in intertidal vegetated habitats of a Mesotidal coastal lagoon
Coastal vegetated ecosystems such as saltmarshes
and seagrasses are important sinks of organic carbon (OC) and total nitrogen (TN), with large global
and local variability, driven by the confluence of
many physical and ecological factors. Here we
show that sedimentary OC and TN stocks of intertidal saltmarsh (Sporobolus maritimus) and seagrass
(Zostera noltei) habitats increased between two- and
fourfold along a decreasing flow velocity gradient
in Ria Formosa lagoon (south Portugal). A similar
twofold increase was also observed for OC and TN
burial rates of S. maritimus and of almost one order
of magnitude for Z. noltei. Stable isotope mixing models identify allochthonous particulate organic
matter as the main source to the sedimentary pools
in both habitats (39–68%). This is the second estimate of OC stocks and the first of OC burial rates in
Z. noltei, a small, fast-growing species that is widely
distributed in Europe (41,000 ha) and which area is
presently expanding (8600 ha in 2000s). Its wide
range of OC stocks (29–99 Mg ha-1
) and burial
rates (15–122 g m2 y-1
) observed in Ria Formosa
highlight the importance of investigating the drivers of such variability to develop global blue carbon models. The TN stocks (7–11 Mg ha-1
) and
burial rates (2–4 g m-2 y-1
) of Z. noltei were generally higher than seagrasses elsewhere. The OC
and TN stocks (29–101 and 3–11 Mg ha-1
, respectively) and burial rates (19–39 and 3–5 g m-2 y-1
)
in S. maritimus saltmarshes are generally lower than
those located in estuaries subjected to larger accumulation of terrestrial organic matter.DL57/2016/CP1361/CT0002; MinECo, MDM2015-0552info:eu-repo/semantics/publishedVersio
An in‑planta comparative study of Plasmopara viticola proteome reveals diferent infection strategies towards susceptible and Rpv3‑mediated resistance hosts
Plasmopara viticola, an obligate biotrophic oomycete, is the causal agent of one of the most harmful grapevine diseases, downy mildew. Within this pathosystem, much information is gathered on the host, as characterization of pathogenicity and infection strategy of a biotrophic pathogen is quite challenging. Molecular insights into P. viticola development and pathogenicity are just beginning to be uncovered, mainly by transcriptomic studies. Plasmopara viticola proteome and secretome were only predicted based on transcriptome data. In this study, we have identified the in-planta proteome of P. viticola during infection of a susceptible ('Trincadeira') and a Rpv3-mediated resistance ('Regent') grapevine cultivar. Four hundred and twenty P. viticola proteins were identified on a label-free mass spectrometry-based approach of the apoplastic fluid of grapevine leaves. Overall, our study suggests that, in the compatible interaction, P. viticola manipulates salicylic-acid pathway and isoprenoid biosynthesis to enhance plant colonization. Furthermore, during the incompatible interaction, development-associated proteins increased while oxidoreductases protect P. viticola from ROS-associated plant defence mechanism. Up to our knowledge this is the first in-planta proteome characterization of this biotrophic pathogen, thus this study will open new insights into our understanding of this pathogen colonization strategy of both susceptible and Rpv3-mediated resistance grapevine genotypes.info:eu-repo/semantics/publishedVersio
Electrodialytic removal of tungsten and arsenic from secondary mine resources – Deep eutectic solvents enhancement
UID/AMB/04085/2019.
LAQV UID/QUI/50006/2019.
PD\BD\135170\2017.
IF/01146/2015.Tungsten is a critical raw material for European and U.S. economies. Tungsten mine residues, usually considered an environmental burden due to e.g. arsenic content, are also secondary tungsten resources. The electrodialytic (ED) process and deep eutectic solvents (DES) have been successfully and independently applied for the extraction of metals from different complex environmental matrices. In this study a proof of concept demonstrates that coupling DES in a two-compartment ED set-up enhances the removal and separation of arsenic and tungsten from Panasqueira mine secondary resources. Choline chloride with malonic acid (1:2), and choline chloride with oxalic acid (1:1) were the DES that in batch extracted the average maximum contents of arsenic (16%) and tungsten (9%) from the residues. However, when ED was operated at a current intensity of 100 mA for 4 days, the extraction yields increased 22% for arsenic and 11% for tungsten, comparing to the tests with no current. From the total arsenic and tungsten extracted, 82% and 77% respectively were successfully removed from the matrix compartment, as they electromigrated to the anolyte compartment, from where these elements can be further separated. This achievement potentiates circular economy, as the final treated residue could be incorporated in construction materials production, mitigating current environmental problems in both mining and construction sectors.proofpublishe
Thin-layer nanofiltration membranes using engineered biopolymers for seawater desalination pre-treatment processes
Nowadays water demand already exceeds supply and water scarcity is a global problem. So it is
necessary to develop novel technologies to be able to use poorer quality source waters for drinking
water production. Once considered as an expensive, ultimate solution for water supply, desalination is
becoming affordable. The two most commonly used seawater desalination methods are Multi-stage
Flash Distillation (MSF) and Seawater Reverse Osmosis (SWRO). SWRO is less energy demanding
compared to MSF, which makes it economically attractive. However there is no backpulsing of the
expensive and delicate reverse osmosis (RO) membranes with air or water, so they are susceptible to
fouling, causing the loss of their performance. Therefore cleaning the feed water to the highest level
possible by nanofiltration, before it reaches the RO membranes would highly increase the efficiency of
the process.
Nanofiltration (NF) as a feed pre-treatment step is a pressure driven membrane separation process that
takes place on a selective layer formed by a semipermeable membrane with properties between RO
and ultrafiltration. The objective of this project is the developement of highly efficient thin-film composite
(TFC) membranes for SWRO pre-treatment processes based on low-fouling cyanobacterial extracellular
polymeric substances (EPS). TFC membranes combine high flux and mechanical strenght, and they are
expected to be the key components of any water purification technology in the future.
Cyanobacterial EPS are complex heteropolysaccharides with putative antimicrobial and antiviral
properties and a particular affinity to bind metal ions [1,2].Within this work, the unicellular N2-fixing
marine cyanobacterium Cyanothece sp. CCY 0110 was chosen for RPS production, since it is among
the most efficient released polysaccharide (RPS) producers and the polymer has been previously
extensively characterised [3]. RPS was produced by growing Cyanothece CCY 0110 in 10L bioreactors,
in conditions previously defined and the polymer was isolated following the standard methodology [3].
A polyvinyl alcohol (PVA) / cyanobacterial EPS blend nanofibrous membranes were fabricated by
electrospinning using polyvinylidene fluoride (PVDF) as a basal membrane, in order to obtain thin-layer
composite nanofiltration membranes. The production of the nanofibers using EPS and PVA as
plasticizer in different ratios was produced in a NF-103 MECC Nanon electrospinning equipment with an
applied electric field between 15 and 25 kV and a flow of 0,2 mL/h.
Morphological, mechanical, chemical and thermal characterization of the electrospun fibers deposited
on the basal membranes, were evaluated by atomic force microscopy (AFM), scanning electron
microscopy (SEM) and energy dispersive spectroscopy (EDS), dynamical and mechanical analysis
(DMA), thermogravimetry (TGA) and differential scanning calorimetry (DSC).
The AFM and SEM results show the presence of fibers with dimensions between 54 and 121 nm with
low bead formation. In the EDS analysis presence of sulfur elements was observed confirming the
inclusion of EPS in the nanofibers. The morphology and diameter of the nanofibers were mainly affected
by the concentration of the blend solution and the weight ratio of the blend, respectively. The best
PVA/EPS nanofibers were achieved in a ratio of 12 % PVA and 0.4 % EPS. The solution conductivity
was ranging 1500 to 3500 μS/cm with a viscosity of about 100 to 500 cP. The DMA results confirmed
the miscibility of PVA/EPS blends. The elastic modulus of the nanocomposite mats increased
significantly as a consequence of the reinforcing effect of EPS. Thermal and mechanical analysis
demonstrated that there were strong intermolecular hydrogen bonds between the molecules EPS-PVA
in the blends. The heat-treated electrospun blended membranes showed better tensile mechanical
properties when compared with PVA alone, and resisted more against disintegration. A lab-scale
nanofiltration was performed in a bench stainless steel Sterlitech tangential flow stirred cell (200 mL)
connected to an air pressure system that allow pressure driven filtration up to 10 BAR.
Bactericidal activity and biofilm formation were tested using Escherichia coli and Sthaphylococcus
aureus as pathogenic microorganisms
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