39 research outputs found
A Central Limit Theorem for intransitive dice
Intransive dice are dice such that
has advantage with respect to , dice has advantage with
respect to and so on, up to , which has advantage over
. In this twofold work, we present: first, (deterministic) results on
existence of general intransitive dice. Second and mainly, a central limit
theorem for the vector of normalized victories of a die against the next one in
the list when the faces of a die are i.i.d.\ random variables and all dice are
independent, but different dice may have distinct distributions associated to,
as well as they may have distinct number of faces. From this central limit
theorem we derive a criteria to assure that the asymptotic probability of
observing intransitive dice is null, which applies for many cases, including
all continuous distributions and many discrete ones.Comment: 37 pages, 3 figure
Extraction and purification of violacein from Yarrowia lipolytica cells using aqueous solutions of surfactants
BACKGROUND: L-Asparaginase (ASNase) is an important biopharmaceutical for the treatment of acute lymphoblastic leukemia (ALL); however, with some restrictions due to its high manufacturing costs. Aqueous biphasic systems (ABS) have been suggested as more economical platforms for the separation/purification of proteins, but a full understanding of the mechanisms behind the ASNase partition is still a major challenge. Polymer/salt-based ABS with different driving-forces (salting-out and hydrophilicity/hydrophobicity effects) were herein applied to control the partition of commercial ASNase.
RESULTS: The main results showed the ASNase partition to the salt- or polymer-rich phase depending on the ABS studied, with extraction efficiencies higher than 95%. For systems composed of inorganic salts, the ASNase partition was controlled by the polyethylene glycol (PEG) molecular weight used. Cholinium-salts-based ABS were able to promote a preferential ASNase partition to the polymer-rich phase using PEG-600 and to the salt-rich phase using a more hydrophobic polypropylene glycol (PPG)-400 polymer. It was possible to select the ABS composed of PEG-2000 + potassium phosphate buffer as the most efficient to separate the ASNase from the main contaminant proteins (purification factor = 2.4 ± 0.2), while it was able to maintain the enzyme activity for posterior application as part of a therapeutic.
CONCLUSION: Polymer/salt ABS can be used to control the partition of ASNase and adjust its purification yields, demonstrating the ABS potential as more economic platform for the selective recovery of therapeutic enzymes from complex broths.publishe
The Egas Moniz histology digital platform : a dream that came true
Abstract in proceedings of the Fourth International Congress of CiiEM: Health, Well-Being and Ageing in the 21st Century, held at Egas Moniz’ University Campus in Monte de Caparica, Almada, from 3–5 June 2019.This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.info:eu-repo/semantics/publishedVersio
Call variation and vocalizations of the stealthy litter frog <em>Ischnocnema abdita</em> (Anura: Brachycephalidae)
Ischnocnema abdita is a small-sized litter frog belonging to the I. verrucosa species series and only known for mountainous areas of southeastern Espírito Santo State, Brazil, in the Municipalities of Santa Teresa (type locality), Cariacica and Mimoso do Sul. In this paper, we describe the calls and provide estimates of within-male variation of I. abdita from its type locality and from a recently discovered population in the region of Alto Caparaó, Municipality of Espera Feliz, Minas Gerais State, Brazil. Additionally, we also performed a GMYC analysis of molecular assignment that recovered the haplotypes of I. abdita from its type locality and from the new record (Alto Caparaó) under the same taxonomical entity. Our bioacoustical analysis revealed two distinct types of calls, herein referred as A and B calls. The A call was observed in both populations, whereas the B call was only recorded at Alto Caparaó. Despite the apparent similarity in the A calls from both localities, we observed differences in all traits analyzed. Moreover, each call trait expressed variation within males. The peak frequency never exceeded 5% variation and it was classified as static in both populations. Temporal parameters, such as call duration and interval between calls were classified either as dynamic or intermediate, with variations ranging from 1.8-66.1% within males. Although number of pulses per note was a dynamic trait at the type locality, it did not vary in both types of call recorded at Alto Caparaó.
Ancestral aneuploidy and stable chromosomal duplication resulting in differential genome structure and gene expression control in trypanosomatid parasites
Aneuploidy is widely observed in both unicellular and multicellular eukaryotes, usually associated with adaptation to stress conditions. Chromosomal duplication stability is a tradeoff between the fitness cost of having unbalanced gene copies and the potential fitness gained from increased dosage of specific advantageous genes. Trypanosomatids, a family of protozoans that include species that cause neglected tropical diseases, are a relevant group to study aneuploidies. Their life cycle has several stressors that could select for different patterns of chromosomal duplications and/or losses, and their nearly universal use of polycistronic transcription increases their reliance on gene expansion/contraction, as well as post-transcriptional control as mechanisms for gene expression regulation. By evaluating the data from 866 isolates covering seven trypanosomatid genera, we have revealed that aneuploidy tolerance is an ancestral characteristic of trypanosomatids but has a reduced occurrence in a specific monophyletic clade that has undergone large genomic reorganization and chromosomal fusions. We have also identified an ancient chromosomal duplication that was maintained across these parasite's speciation, named collectively as the trypanosomatid ancestral supernumerary chromosome (TASC). TASC has most genes in the same coding strand, is expressed as a disomic chromosome (even having four copies), and has increased potential for functional variation, but it purges highly deleterious mutations more efficiently than other chromosomes. The evidence of stringent control over gene expression in this chromosome suggests that these parasites have adapted to mitigate the fitness cost associated with this ancient chromosomal duplication
Building a Portuguese Coalition for Biodiversity Genomics
The diverse physiography of the Portuguese land and marine territory, spanning from continental Europe to the Atlantic archipelagos, has made it an important repository of biodiversity throughout the Pleistocene glacial cycles, leading to a remarkable diversity of species and ecosystems. This rich biodiversity is under threat from anthropogenic drivers, such as climate change, invasive species, land use changes, overexploitation or pathogen (re)emergence. The inventory, characterization and study of biodiversity at inter- and intra-specific levels using genomics is crucial to promote its preservation and recovery by informing biodiversity conservation policies, management measures and research. The participation of researchers from Portuguese institutions in the European Reference Genome Atlas (ERGA) initiative, and its pilot effort to generate reference genomes for European biodiversity, has reinforced the establishment of Biogenome Portugal. This nascent institutional network will connect the national community of researchers in genomics. Here, we describe the Portuguese contribution to ERGA’s pilot effort, which will generate high-quality reference genomes of six species from Portugal that are endemic, iconic and/or endangered, and include plants, insects and vertebrates (fish, birds and mammals) from mainland Portugal or the Azores islands. In addition, we outline the objectives of Biogenome Portugal, which aims to (i) promote scientific collaboration, (ii) contribute to advanced training, (iii) stimulate the participation of institutions and researchers based in Portugal in international biodiversity genomics initiatives, and (iv) contribute to the transfer of knowledge to stakeholders and engaging the public to preserve biodiversity. This initiative will strengthen biodiversity genomics research in Portugal and fuel the genomic inventory of Portuguese eukaryotic species. Such efforts will be critical to the conservation of the country’s rich biodiversity and will contribute to ERGA’s goal of generating reference genomes for European species.info:eu-repo/semantics/publishedVersio
Production of electrospun fast-dissolving drug delivery systems with therapeutic eutectic systems encapsulated in gelatin
Fast-dissolving delivery systems (FDDS) have received increasing attention in
the last years. Oral drug delivery is still the preferred route for the administration of
pharmaceutical ingredients. Nevertheless, some patients, e.g. children or elderly people, have
difficulties in swallowing solid tablets. In this work, gelatin membranes were produced by
electrospinning, containing an encapsulated therapeutic deep-eutectic solvent (THEDES)
composed by choline chloride/mandelic acid, in a 1:2 molar ratio. A gelatin solution (30% w/
v) with 2% (v/v) of THEDES was used to produce electrospun fibers and the experimental
parameters were optimized. Due to the high surface area of polymer fibers, this type of
construct has wide applicability. With no cytotoxicity effect, and showing a fast-dissolving
release profile in PBS, the gelatin fibers with encapsulated THEDES seem to have promising
applications in the development of new drug delivery systems.The research leading to these results has received
funding from Fundação para a Ciência e a Tecnologia
(FCT) through the projects ENIGMA - PTDC/EQU-EPR/
121491/2010 and UID/CTM/50025/2013, LAQVREQUIMTE:
UID/QUI/50006/2013, UCIBIO-REQUIMTE:
UID/Multi/04378/2013 (co-financed by the ERDF under the
PT2020 Partnership Agreement [POCI-01-0145-FEDER-
007728]) and by FEDER through the COMPETE 2020
Programme. Marta Martins is grateful for financial support
from FCT through the grant BIM/PTDC/EQUEPR/121491/
2010/ENIGMA. This research has also received funding from
the European Union Seventh Framework Programme (FP7/
2007-2013) under grant agreement number REGPOTCT2012-316331-POLARIS and from the project BNovel
smart and biomimetic materials for innovative regenerative medicine approaches^ RL1 - ABMR - NORTE-01-0124- FEDER-000016) co-financed by North Portugal Regional
Operational Programme (ON.2 – O Novo Norte), under the
National Strategic Reference Framework (NSRF), through
the European Regional Development Fund (ERDF).info:eu-repo/semantics/publishedVersio
Building a Portuguese coalition for biodiversity genomics
The diverse physiography of the Portuguese land and marine territory, spanning from continental Europe to the Atlantic archipelagos, has made it an important repository of biodiversity throughout the Pleistocene glacial cycles, leading to a remarkable diversity of species and ecosystems. This rich biodiversity is under threat from anthropogenic drivers, such as climate change, invasive species, land use changes, overexploitation, or pathogen (re)emergence. The inventory, characterisation, and study of biodiversity at inter- and intra-specific levels using genomics is crucial to promote its preservation and recovery by informing biodiversity conservation policies, management measures, and research. The participation of researchers from Portuguese institutions in the European Reference Genome Atlas (ERGA) initiative and its pilot effort to generate reference genomes for European biodiversity has reinforced the establishment of Biogenome Portugal. This nascent institutional network will connect the national community of researchers in genomics. Here, we describe the Portuguese contribution to ERGA’s pilot effort, which will generate high-quality reference genomes of six species from Portugal that are endemic, iconic, and/or endangered and include plants, insects, and vertebrates (fish, birds, and mammals) from mainland Portugal or the Azores islands. In addition, we outline the objectives of Biogenome Portugal, which aims to (i) promote scientific collaboration, (ii) contribute to advanced training, (iii) stimulate the participation of institutions and researchers based in Portugal in international biodiversity genomics initiatives, and (iv) contribute to the transfer of knowledge to stakeholders and engaging the public to preserve biodiversity. This initiative will strengthen biodiversity genomics research in Portugal and fuel the genomic inventory of Portuguese eukaryotic species. Such efforts will be critical to the conservation of the country’s rich biodiversity and will contribute to ERGA’s goal of generating reference genomes for European species.info:eu-repo/semantics/publishedVersio
MAMMALS IN PORTUGAL : A data set of terrestrial, volant, and marine mammal occurrences in P ortugal
Mammals are threatened worldwide, with 26% of all species being includedin the IUCN threatened categories. This overall pattern is primarily associatedwith habitat loss or degradation, and human persecution for terrestrial mam-mals, and pollution, open net fishing, climate change, and prey depletion formarine mammals. Mammals play a key role in maintaining ecosystems func-tionality and resilience, and therefore information on their distribution is cru-cial to delineate and support conservation actions. MAMMALS INPORTUGAL is a publicly available data set compiling unpublishedgeoreferenced occurrence records of 92 terrestrial, volant, and marine mam-mals in mainland Portugal and archipelagos of the Azores and Madeira thatincludes 105,026 data entries between 1873 and 2021 (72% of the data occur-ring in 2000 and 2021). The methods used to collect the data were: live obser-vations/captures (43%), sign surveys (35%), camera trapping (16%),bioacoustics surveys (4%) and radiotracking, and inquiries that represent lessthan 1% of the records. The data set includes 13 types of records: (1) burrowsjsoil moundsjtunnel, (2) capture, (3) colony, (4) dead animaljhairjskullsjjaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8),observation in shelters, (9) photo trappingjvideo, (10) predators dietjpelletsjpine cones/nuts, (11) scatjtrackjditch, (12) telemetry and (13) vocalizationjecholocation. The spatial uncertainty of most records ranges between 0 and100 m (76%). Rodentia (n=31,573) has the highest number of records followedby Chiroptera (n=18,857), Carnivora (n=18,594), Lagomorpha (n=17,496),Cetartiodactyla (n=11,568) and Eulipotyphla (n=7008). The data setincludes records of species classified by the IUCN as threatened(e.g.,Oryctolagus cuniculus[n=12,159],Monachus monachus[n=1,512],andLynx pardinus[n=197]). We believe that this data set may stimulate thepublication of other European countries data sets that would certainly contrib-ute to ecology and conservation-related research, and therefore assisting onthe development of more accurate and tailored conservation managementstrategies for each species. There are no copyright restrictions; please cite thisdata paper when the data are used in publications.info:eu-repo/semantics/publishedVersio