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1.
Materials (Basel) ; 15(3)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35160763

RESUMO

This research aims at gaining a further understanding of the impact of accelerating admixtures on the reactivity of supplementary cementitious materials (SCMs), which are widely used as a clinker replacement in blended cements. This was done on synthetic glasses with controlled composition and structure that mimic two types of real SCMs (slag and calcium-rich fly ash). The effects of DEIPA, TIPA, NaSCN and Na2S2O3 on the glass dissolution, hydration kinetics and reaction products were investigated. The obtained results concluded that the pH of the NaOH solution and the composition of the synthetic glass play a key role on the effect of the admixtures. In 0.1 M NaOH (pH = 13.0), all the studied admixtures inhibited the dissolution of slag-like glasses while they enhanced the dissolution of Ca-rich fly ash-like glasses, being Na2S2O3 the admixture that led to the highest increase of the dissolution rate of the Ca-rich fly ash-type glasses. In 1 M NaOH solutions (pH = 13.8), only the alkali admixtures (NaSCN and Na2S2O3) enhanced the degree of reaction of both glasses. In slag-type glasses pastes mixed with 1 M NaOH, the addition of 2% Na2S2O3 induced the highest increase of their reactivity as inferred by the total heat release and the amount of bound water. This is related to the formation of a high amount of S(II)-AFm, in addition to C-A-S-H, that would increase the aluminium undersaturation of the pore solution and consequently the further dissolution of the glass.

2.
Ocul Immunol Inflamm ; 30(2): 318-319, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32976059

RESUMO

PURPOSE: To describe a case of bilateral acute iris transillumination (BAIT)-like syndrome following intracameral moxifloxacin injection after cataract surgery. METHODS: A case report. RESULTS: We report a case of unilateral acute iris transillumination and distorted pupil in a 53-year-old male who underwent uneventful cataract extraction with intracameral moxifloxacin. CONCLUSION: BAIT-like syndrome may be a rare side effect of intracameral moxifloxacin.


Assuntos
Iris , Transiluminação , Antibacterianos/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Moxifloxacina/efeitos adversos , Síndrome
3.
Environ Sci Pollut Res Int ; 29(41): 61623-61629, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34775562

RESUMO

During gestation, essential and non-essential trace elements are transferred from the pregnant females to embryos. This study aimed to determine and compare the concentrations of seven essential trace elements (Fe, Zn, Se, Cu, Mn, Cr, Co) and six non-essential trace elements (As, Cd, V, U, Tl, Ag) in the muscle and the liver of a Munk's pygmy devil ray pregnant female, Mobula munkiana, and its embryo. Transfer evidence of essential and non-essential trace elements was detected in M. munkiana tissues. Arsenic was found in elevated concentrations in the pregnant female and the embryo tissues. Elevated levels of Cd, V, U, and Ag were found in the pregnant female liver, but were minimal in the embryo tissue. This is the first study to investigate maternal transfer of essential and non-essential trace elements in these species and their reproductive strategy.


Assuntos
Arsênio , Oligoelementos , Cádmio , Feminino , Humanos , Fígado , Músculos , Gravidez
4.
Front Pediatr ; 10: 899445, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36619503

RESUMO

The COVID-19 pandemic represents a valuable opportunity to carry out cohort studies that allow us to advance our knowledge on pathophysiological mechanisms of neuropsychiatric diseases. One of these opportunities is the study of the relationships between inflammation, brain development and an increased risk of suffering neuropsychiatric disorders. Based on the hypothesis that neuroinflammation during early stages of life is associated with neurodevelopmental disorders and confers a greater risk of developing neuropsychiatric disorders, we propose a cohort study of SARS-CoV-2-infected pregnant women and their newborns. The main objective of SIGNATURE project is to explore how the presence of prenatal SARS-CoV-2 infection and other non-infectious stressors generates an abnormal inflammatory activity in the newborn. The cohort of women during the COVID-19 pandemic will be psychological and biological monitored during their pregnancy, delivery, childbirth and postpartum. The biological information of the umbilical cord (foetus blood) and peripheral blood from the mother will be obtained after childbirth. These samples and the clinical characterisation of the cohort of mothers and newborns, are tremendously valuable at this time. This is a protocol report and no analyses have been conducted yet, being currently at, our study is in the recruitment process step. At the time of this publication, we have identified 1,060 SARS-CoV-2 infected mothers and all have already given birth. From the total of identified mothers, we have recruited 537 SARS-COV-2 infected women and all of them have completed the mental health assessment during pregnancy. We have collected biological samples from 119 mothers and babies. Additionally, we have recruited 390 non-infected pregnant women.

5.
Sci Rep ; 11(1): 132, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420295

RESUMO

Munk's pygmy devil rays (Mobula munkiana) are medium-size, zooplanktivorous filter feeding, elasmobranchs characterized by aggregative behavior, low fecundity and delayed reproduction. These traits make them susceptible to targeted and by-catch fisheries and are listed as Vulnerable on the IUCN Red List. Multiple studies have examined fisheries impacts, but nursery areas or foraging neonate and juvenile concentrations have not been examined. This study describes the first nursery area for M. munkiana at Espiritu Santo Archipelago, Mexico. We examined spatial use of a shallow bay during 22 consecutive months in relation to environmental patterns using traditional tagging (n = 95) and acoustic telemetry (n = 7). Neonates and juveniles comprised 84% of tagged individuals and their residency index was significantly greater inside than outside the bay; spending a maximum of 145 consecutive days within the bay. Observations of near-term pregnant females, mating behavior, and neonates indicate an April to June pupping period. Anecdotal photograph review indicated that the nursery area is used by neonates and juveniles across years. These findings confirm, for the first time, the existence of nursery areas for Munk's pygmy devil rays and the potential importance of shallow bays during early life stages for the conservation of this species.


Assuntos
Ecossistema , Rajidae/crescimento & desenvolvimento , Animais , California , Feminino , Masculino , México , Estações do Ano
9.
Index enferm ; 27(3): 138-142, jul.-sept. 2018. tab
Artigo em Espanhol | IBECS | ID: ibc-180556

RESUMO

Objetivo: Explorar necesidades formativas percibidas por las personas mayores de 60 años al envejecer y conocer los beneficios o barreras de participar en cursos de formación dirigidos a ellos. Metodología: Estudio cualitativo con grupos focales realizado en áreas básicas de salud y un centro social de Mataró (Barcelona). Se estudiaron 29 sujetos divididos en: personas mayores de 60 años que acudían a un centro de atención primaria y personas mayores de 60 de una asociación de personas mayores. Se organizaron 4 grupos focales estratificados por segmentos. Se transcribieron las grabaciones elaborando categorías, se codificaron y analizaron. Resultados: Los participantes tenían vidas plenas, apoyos emocionales y vínculos positivos con su comunidad y familia. Manifestaron que es importante planificar el envejecimiento y actividades para realizar al jubilarse. Conclusión: Es necesario recibir formación al envejecer. Principales barreras: obligación de cuidar, falta de tiempo y coste económico


Objective: To explore formative needs perceived by people older than 60 years when aging and to know the benefits and/or barriers of participating in training courses focused on them. Methods: Qualitative study with focus groups made in basic areas of primary care and a social center of Mataró (Barcelona).29 subjects were studied, divided into: people over 60 years attending a primary care center and people over 60 belonging to an association of elderly. 4 focus groups stratified by segments were organized. The recordings were transcribed elaborating categories, they were codified and analyzed. Results: The participants had full lives, emotional support and positive links with their community and family. They stated that it is important to plan aging and activities to do when retiring. Conclusions: To receive training is needed when aging. Main barriers: obligation to take care of, lack of time, economic cost


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Pessoas com Deficiência , Necessidades e Demandas de Serviços de Saúde , Envelhecimento , Adaptação Psicológica , Aposentadoria , 25783 , Responsabilidade Social
11.
Nat Commun ; 7: 10952, 2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-27009966

RESUMO

Silicate hydration is prevalent in natural and technological processes, such as, mineral weathering, glass alteration, zeolite syntheses and cement hydration. Tricalcium silicate (Ca3SiO5), the main constituent of Portland cement, is amongst the most reactive silicates in water. Despite its widespread industrial use, the reaction of Ca3SiO5 with water to form calcium-silicate-hydrates (C-S-H) still hosts many open questions. Here, we show that solid-state nuclear magnetic resonance measurements of (29)Si-enriched triclinic Ca3SiO5 enable the quantitative monitoring of the hydration process in terms of transient local molecular composition, extent of silicate hydration and polymerization. This provides insights on the relative influence of surface hydroxylation and hydrate precipitation on the hydration rate. When the rate drops, the amount of hydroxylated Ca3SiO5 decreases, thus demonstrating the partial passivation of the surface during the deceleration stage. Moreover, the relative quantities of monomers, dimers, pentamers and octamers in the C-S-H structure are measured.

12.
Langmuir ; 29(8): 2756-63, 2013 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-23363393

RESUMO

We report the preparation of different surface patterns based on the photo-cross-linking/degradation kinetics of polystyrene (PS) by using UV light. Upon exposure to UV light, PS can be initially cross-linked, whereas an excess of the exposure time or intensity provokes the degradation of the material. Typically photolithography employs either positive or negative photoresist layers that upon removal of either the exposed or the nonexposed areas transfer the pattern of the mask. Herein, we present a system that can be both negative and positive depending on several aspects, including the irradiation time, intensity, or presence of absorbing active species (photoinitiators) using a general setup. As a result of the optimization of the time of exposure and the use of an appropriate cover or the incorporation of an appropriate amount of photoinitiator (in this particular case IRG 651), different tailor-made surface patterns can be obtained. Moreover, changes of the chemical composition of the polystyrene using, for instance, block copolymers can lead to surface patterns with variable functional groups. In this study we describe the formation of surface patterns using polystyrene-block-poly(2,3,4,5,6-pentafluorostyrene) block copolymers. The introduction of fluorinated moieties clearly modifies the wettability of the films when compared with that of the same structures obtained with PS. As a consequence we present herein a patterning methodology that can simultaneously vary not only the morphology but also the surface chemical composition.


Assuntos
Poliestirenos/química , Raios Ultravioleta , Cinética , Estrutura Molecular , Poliestirenos/síntese química , Propriedades de Superfície
13.
Bioconjug Chem ; 18(1): 121-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17226964

RESUMO

We report the synthesis of new photonuclease 4 consisting of two acridine rings joined by a pyridine-based copper binding linker. We have shown that photocleavage of plasmid DNA is markedly enhanced when this ligand is irradiated in the presence of copper(II) (419 nm, 22 degrees C, pH 7.0). Viscometric data indicate that 4 binds to DNA by monofunctional intercalation, and equilibrium dialysis provides an estimated binding constant of 1.13 x 105 M-1 for its association with calf thymus DNA. In competition dialysis experiments, 4 exhibits preferential binding to GC-rich DNA sequences. When Cu(II) is added at a ligand to metal ratio of 1:1, electrospray ionization mass spectrometry demonstrates that compound 4 undergoes complex formation, while thermal melting studies show a 10 degrees C increase in the Tm of calf thymus DNA. Groove binding and intercalation are suggested by viscometric data. Finally, colorimetric and scavenger experiments indicate that the generation of Cu(I), H2O2, and superoxide contributes to the production of DNA frank strand breaks by the Cu(II) complex of 4. Whereas the strand breaks are distributed in a relatively uniform fashion over the four DNA bases, subsequent piperidine treatment of the photolysis reactions shows that alkaline labile lesions occur predominantly at guanine.


Assuntos
Acridinas/química , Cobre/química , DNA/química , Substâncias Intercalantes/química , Piridinas/química , Animais , Bovinos , Ligantes , Estrutura Molecular , Desnaturação de Ácido Nucleico , Fotoquímica , Plasmídeos/genética , Espectrometria de Massas por Ionização por Electrospray , Análise Espectral , Temperatura de Transição , Viscosidade
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