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Early infant development is a maturation process critically depends on the infant's interaction with primary caregivers. Hence, neonatal units prioritize their proximity. In COVID‐19, parental visitation hours were limited, reducing caregivers time with their infants. This follow‐up study analyzes and compares levels of maternal depression and stress, infant development, and bonding quality in preterm mother‐infant dyads hospitalized, before and during the pandemic. Out of 66 dyads participated, 36 were admitted before COVID‐19, and 30 during COVID‐19. The assessed was two video‐call sessions in which mothers completed selected questionnaires. No significant differences between mothers' levels of depression and stress. However, low birth weight was associated with greater difficulties in children's communication and interpersonal relationships. Furthermore, infants hospitalized in COVID‐19 had a higher risk of experiencing delayed communication. No significant differences were observed in bonding quality. Lower infant gestational age and longer breastfeeding time were associated with better bonding quality in both groups. Psychosocial intervention is considered a valuable tool, capable of preventing maternal mental health difficulties and protecting bonding in premature infants and in highly complex healthcare settings. Nevertheless, it is essential to more actively address the socio‐affective needs of newborns during their hospital stay to promote adequate development. [ABSTRACT FROM AUTHOR]

The evolution of circumstellar discs is influenced by their surroundings. The relevant processes include external photoevaporation due to nearby stars and dynamical truncations. The impact of these processes on disc populations depends on the star-formation history and on the dynamical evolution of the region. Since star-formation history and the phase-space characteristics of the stars are important for the evolution of the discs, we start simulating the evolution of the star cluster with the results of molecular cloud collapse simulations. In the simulation, we form stars with circumstellar discs, which can be affected by different processes. Our models account for the viscous evolution of the discs, internal and external photoevaporation of gas, external photoevaporation of dust, and dynamical truncations. All these processes are resolved together with the dynamical evolution of the cluster, and the evolution of the stars. An extended period of star formation, lasting for at least 2 Myr, results in some discs being formed late. These late-formed discs have a better chance of survival because the cluster gradually expands with time, and a lower local stellar density reduces the effects of photoevaporation and dynamical truncation. Late formed discs can then be present in regions of high UV radiation, solving the proplyd lifetime problem. We also find a considerable fraction of discs that lose their gas content but remain sufficiently rich in solids to be able to form a rocky planetary system. [ABSTRACT FROM AUTHOR]

Circumstellar discs are the precursors of planetary systems and develop shortly after their host star has formed. In their early stages, these discs are immersed in an environment rich in gas and neighbouring stars, which can be hostile for their survival. There are several environmental processes that affect the evolution of circumstellar discs, and external photoevaporation is arguably one of the most important ones. Theoretical and observational evidence point to circumstellar discs losing mass quickly when in the vicinity of massive, bright stars. In this work, we simulate circumstellar discs in clustered environments in a range of stellar densities, where the photoevaporation mass-loss process is resolved simultaneously with the stellar dynamics, stellar evolution, and the viscous evolution of the discs. Our results indicate that external photoevaporation is efficient in depleting disc masses and that the degree of its effect is related to stellar density. We find that a local stellar density lower than 100 stars pc−2 is necessary for discs massive enough to form planets to survive for 2.0 Myr. There is an order of magnitude difference in the disc masses in regions of projected density 100 versus 104 stars pc−2. We compare our results to observations of the Lupus clouds, the Orion Nebula Cluster, the Orion Molecular Cloud-2, Taurus, and NGC 2024, and find that the trends observed between region density and disc masses are similar to those in our simulations. [ABSTRACT FROM AUTHOR]

Planet-forming circumstellar discs are a fundamental part of the star formation process. Since stars form in a hierarchical fashion in groups of up to hundreds or thousands, the UV radiation environment that these discs are exposed to can vary in strength by at least six orders of magnitude. This radiation can limit the masses and sizes of the discs. Diversity in star forming environments can have long lasting effects in disc evolution and in the resulting planetary populations. We perform simulations to explore the evolution of circumstellar discs in young star clusters. We include viscous evolution, as well as the impact of dynamical encounters and external photoevaporation. We find that photoevaporation is an important process in destroying circumstellar discs: in regions of stellar density ρ ∼ 100 M⊙ pc−3 around |$80{{\ \rm per\ cent}}$| of discs are destroyed before |$2\, \hbox{Myr}$| of cluster evolution. In regions of ρ ∼ 50 M⊙ pc−3 around |$50{{\ \rm per\ cent}}$| of discs are destroyed in the same time-scale. Our findings are in agreement with observed disc fractions in young star-forming regions and support previous estimations that planet formation must start in time-scales <0.1–1 Myr. [ABSTRACT FROM AUTHOR]

Stars with circumstellar discs may form in environments with high stellar and gas densities that affects the discs through processes like truncation from dynamical encounters, ram pressure stripping, and external photoevaporation. Circumstellar discs also undergo viscous evolution that leads to disc expansion. Previous work indicates that dynamical truncation and viscous evolution play a major role in determining circumstellar disc size and mass distributions. However, it remains unclear under what circumstances each of these two processes dominates. Here, we present results of simulations of young stellar clusters taking viscous evolution and dynamical truncations into account. We model the embedded phase of the clusters by adding leftover gas as a background potential that can be present through the whole evolution of the cluster, or expelled after |$1\, \mathrm{Myr}$|⁠. We compare our simulation results to actual observations of disc sizes, disc masses, and accretion rates in star-forming regions. We argue that the relative importance of dynamical truncations and the viscous evolution of the discs changes with time and cluster density. Viscous evolution causes the importance of dynamical encounters to increase in time, but the encounters cease soon after the expulsion of the leftover gas. For the clusters simulated in this work, viscous growth dominates the evolution of the discs. [ABSTRACT FROM AUTHOR]

Objective: to describe whether there were differences in sociodemographic, obstetric, perinatal and psychological variables between immigrant women and native-born women in Spain during the first 24 h after delivery. Background: The immediate postpartum period is a critical time when physical and psychological disorders are likely to occur. Immigrant women have, in general, poor perinatal and psychological results during this time. Methods: One hundred and three women at the Virgen de las Nieves University Hospital (Granada, Spain) were divided into two groups: 50 Spanish and 53 immigrants. The instruments used were the Life Orientation Test, the Stress Vulnerability Inventory, the Perceived Stress Scale and the Symptom Checklist-90-Revised (SCL-90-R). Sociodemographic and obstetric data were obtained from the healthcare providers reports. Results: During the postpartum period, the immigrant women had higher mean scores on the following subscales: interpersonal sensitivity (F(1,102) = 4.06;p < 0.05); depression (F(1,102) = 7.24;p < 0.01); phobic anxiety (F(1,102) = 4.83;p < 0.05), paranoid ideation (F(1,102) = 7.20;p < 0.01); and psychoticism (F(1,102) = 4.04;p < 0.05). When considering age, education, profession, job situation, immigrant status of the partner and duration of time in Spain as covariates, differences between groups were significant on obsessive–compulsiveness (F(1,102) = 5.37;p < 0.05) and depression (F(1,102) = 6.89;p < 0.05). Conclusions: Immigrant women are in need of more psychological and emotional support from their families, midwives and the rest of healthcare providers than are native Spaniards immediately after delivery. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this work is the development of a biosensor to determine uric acid on serum. The biosensor has been developed through enzymatic immobilization of uricase from Candida spp. and peroxidase from horseradish on mesoporous silica with hexagonal symmetry (MCM-41). The mesoporous material was immobilized by Nafion assisted adsorption on a glassy carbon electrode, which was used as working electrode. Measurements were performed in a conventional three electrodes cell. The biosensor configuration allowed a fast, sensitive and stable electrochemical detection of hydrogen peroxide generated by the enzyme reaction. All experimental variables involved in the preparation and performance of the enzyme biosensor were optimized. Amperometry in stirred solutions at −100mV provided a linear calibration plot for uric acid in the 2–10μM concentration range. Furthermore, the proposed biosensor showed excellent analytical performance with detection and quantification limits of 0.33μM and 2μM, respectively; analytical sensitivity of 3.908nAμM−1, repeatability <2.11% and a long-term stability of 14 days (daily measurements). The biosensor yielded good results in the determination of uric acid in spiked human serum samples. [Copyright &y& Elsevier]

Expression of the anaerobically inducible focA-pfl operon in Escherichia coli was activated nearly sevenfold relative to wild-type under aerobic growth conditions by increasing the dosage of the fnr gene on a pBR322-based plasmid (pCH21). No effect on anaerobic expression levels was observed, suggesting that operon expression under these conditions is maximal. Examination of the complex transcript pattern of the focA-pfl operon confirmed that in strains bearing pCH21 all transcripts, with the exception of the promoter 7 transcript, were up-regulated aerobically. Western analysis of strains bearing pCH21 revealed that the fumarate nitrate regulator (FNR) level was increased approximately ninefold relative to the level in strains bearing a single copy of the fnr gene aerobically, but was only overproduced threefold anaerobically. Analysis of an fnr-lacZ fusion indicated that fnr expression was more strongly negatively autoregulated in anaerobic cells compared with aerobic cells when pCH21 was present. Taken together, these findings suggest that high-level overproduction of FNR is prevented anaerobically by active FNR repressing expression of the fnr gene. Furthermore, transcription from promoter 7 of the focA-pfl operon, which depends on both ArcA-P and FNR, cannot be activated aerobically by overproduction of FNR alone, while promoter 6, which is less dependent on ArcA-P, can be activated under these conditions. [ABSTRACT FROM AUTHOR]

Summary: Sphingopyxis granuli TFA is a contaminant degrading alphaproteobacterium that responds to adverse conditions by inducing the general stress response (GSR), an adaptive response that controls the transcription of a variety of genes to overcome adverse conditions. The core GSR regulators (the response regulator PhyR, the anti‐σ factor NepR and the σ factor EcfG) are duplicated in TFA, being PhyR1 and PhyR2, NepR1 and NepR2 and EcfG1 and EcfG2. Based on multiple genetic, phenotypical and biochemical evidences including in vitro transcription assays, we have assigned distinct functional features to each paralogue and assessed their contribution to the GSR regulation, dictating its timing and the intensity. We show that different stress signals are differentially integrated into the GSR by PhyR1 and PhyR2, therefore producing different levels of GSR activation. We demonstrate in vitro that both NepR1 and NepR2 bind EcfG1 and EcfG2, although NepR1 produces a more stable interaction than NepR2. Conversely, NepR2 interacts with phosphorylated PhyR1 and PhyR2 more efficiently than NepR1. We propose an integrative model where NepR2 would play a dual negative role: it would directly inhibit the σ factors upon activation of the GSR and it would modulate the GSR activity indirectly by titrating the PhyR regulators. [ABSTRACT FROM AUTHOR]

The genes for tetralin (thn) utilization in Sphingomonas macrogolitabida strain TFA are regulated at the transcriptional level by ThnR, ThnY and ThnA3. ThnR, a LysR-type transcriptional activator activates transcription specifically in response to tetralin, and ThnY is an iron-sulfur flavoprotein that may activate ThnR by protein-protein interaction. ThnA3, a Rieske-type ferredoxin that transfers electrons to the tetralin dioxygenase, prevents transcription of thn genes when the inducer molecule of the pathway is a poor substrate for the dioxygenase. The mechanism by which ThnA3 transduces this signal to the regulatory system is a major question concerning thn gene regulation. Here, we have confirmed the discriminatory function of ThnA3 and the negative role of its reduced form. We have generated ThnY variants with amino acid exchanges in the [2Fe-2S], FAD and NAD(P) H binding domains and their regulatory properties have been analyzed. Two variants, ThnY-C40S and ThnY-N201G,S206P have completely lost the discriminatory function of the regulatory system because they induced thn gene expression with different molecules such us cis-decalin, cyclohexane, trans-decalin, or benzene, which are not real inducers of the pathway. These results support a model in which ThnA3 exerts its negative modulation via the regulator ThnY. [ABSTRACT FROM AUTHOR]

Empirical evidence demonstrates the effect of productive failure (Kapur, 2008) on disciplinary knowledge. However, there is no clear theoretical explanation for why this is the case. Empirical evidence on argumentation and education shows the impact of curricular embedded deliberative argumentation on learning. However, these two trends of research have been mainly isolated, with insufficient synergy. Through the analysis of a group of sixth-graders collaborating around problems of natural selection, the aim of this paper is the theoretical exploration of the process of learning in productive failure designs through a focus on argumentative peer dialogue. The paper proposes an articulation of these two fields of research (productive failure and argumentation), which sheds light on both the learning dynamics in productive failure settings and the relevant insights for argumentative designs. The new possibilities for empirical research on learning through peer interaction opened up by these interconnected fields of research are proposed and discussed. [ABSTRACT FROM AUTHOR]

Science teaching has been called to contribute to citizenship insofar as it requires scientific competencies such as articulating theory and evidence, and the critical evaluation of different points of view. To promote argumentation in science teaching is key but not simple and requires teachers' pedagogical content knowledge (PCK) of argumentation. International literature has reported low PCK of argumentation in science teachers, but we scarcely know about this in Spanish speaking countries. This paper reports a study aimed at describing the PCK of argumentation on 10 primary science teachers in Chile. Lessons were video recorded, and interviews were conducted. Results show low PCK of argumentation overall, and declarative PCK does not necessarily relates with procedimental PCK. Moreover, different configurations of the dimensions of PCK of argumentation were observed, suggesting that there is not one possible learning progression, but different ones. Educational and scientific implications are discussed. [ABSTRACT FROM AUTHOR]

The polynomial affine gravity is a model that is built up without the explicit use of a metric tensor field. In this article we reformulate the three-dimensional model and, given the decomposition of the affine connection, we analyse the consistently truncated sectors. Using the cosmological ansatz for the connection, we scan the cosmological solutions on the truncated sectors. We discuss the emergence of different kinds of metrics. [ABSTRACT FROM AUTHOR]

The ability of bacterial core RNA polymerase (RNAP) to interact with different σ factors, thereby forming a variety of holoenzymes with different specificities, represents a powerful tool to coordinately reprogram gene expression. Extracytoplasmic function σ factors (ECFs), which are the largest and most diverse family of alternative σ factors, frequently participate in stress responses. The classification of ECFs in 157 different groups according to their phylogenetic relationships and genomic context has revealed their diversity. Here, we have clustered 55 ECF groups with experimentally studied representatives into two broad classes of stress responses. The remaining 102 groups still lack any mechanistic or functional insight, representing a myriad of systems yet to explore. In this work, we review the main features of ECFs and discuss the different mechanisms controlling their production and activity, and how they lead to a functional stress response. Finally, we focus in more detail on two well-characterized ECFs, for which the mechanisms to detect and respond to stress are complex and completely different: Escherichia coli RpoE, which is the best characterized ECF and whose structural and functional studies have provided key insights into the transcription initiation by ECF-RNAP holoenzymes, and the ECF15-type EcfG, the master regulator of the general stress response in Alphaproteobacteria. [ABSTRACT FROM AUTHOR]

Sphingopyxis granuli strain TFA is able to grow on the organic solvent tetralin as the only carbon and energy source. The aerobic catabolic pathway for tetralin, the genes involved and their regulation have been fully characterised. Unlike most of the bacteria belonging to the sphingomonads group, this strain is able to grow in anoxic conditions by respiring nitrate, though not nitrite, as the alternative electron acceptor. In this work, two fnr-like genes, fnrN and fixK, have been identified in strain TFA. Both genes are functional in E. coli and Sphingopyxis granuli although fixK, whose expression is apparently activated by FnrN, seems to be much less effective than fnrN in supporting anaerobic growth. Global transcriptomic analysis of a ΔfnrN ΔfixK double mutant and identification of Fnr boxes have defined a minimal Fnr regulon in this bacterium. However, expression of a substantial number of anaerobically regulated genes was not affected in the double mutant. Additional regulators such regBA, whose expression is also activated by Fnr, might also be involved in the anaerobic response. Anaerobically induced stress response genes were not regulated by Fnr but apparently induced by stress conditions inherent to anaerobic growth, probably due to accumulation of nitrite and nitric oxide. [ABSTRACT FROM AUTHOR]

Under ever-changing environmental conditions, the General Stress Response (GSR) represents a lifesaver for bacteria in order to withstand hostile situations. In α-proteobacteria, the EcfG-type extracytoplasmic function (ECF) σ factors are the key activators of this response at the transcriptional level. In this work, we address the hierarchical function of the ECF σ factor paralogs EcfG1 and EcfG2 in triggering the GSR in Sphingopyxis granuli TFA and describe the role of EcfG2 as global switch of this response. In addition, we define a GSR regulon for TFA and use in vitro transcription analysis to study the relative contribution of each EcfG paralog to the expression of selected genes. We show that the features of each promoter ultimately dictate this contribution, though EcfG2 always produced more transcripts than EcfG1 regardless of the promoter. These first steps in the characterisation of the GSR in TFA suggest a tight regulation to orchestrate an adequate protective response in order to survive in conditions otherwise lethal. [ABSTRACT FROM AUTHOR]

Tetralin (1,2,3,4-tetrahydonaphthalene) is a recalcitrant compound that consists of an aromatic and an alicyclic ring. It is found in crude oils, produced industrially from naphthalene or anthracene, and widely used as an organic solvent. Its toxicity is due to the alteration of biological membranes by its hydrophobic character and to the formation of toxic hydroperoxides. Two unrelated bacteria, Sphingopyxis granuli strain TFA and Rhodococcus sp. strain TFB were isolated from the same niche as able to grow on tetralin as the sole source of carbon and energy. In this review, we provide an overview of current knowledge on tetralin catabolism at biochemical, genetic and regulatory levels in both strains. Although they share the same biodegradation strategy and enzymatic activities, no evidences of horizontal gene transfer between both bacteria have been found. Moreover, the regulatory elements that control the expression of the gene clusters are completely different in each strain. A special consideration is given to the complex regulation discovered in TFA since three regulatory systems, one of them involving an unprecedented communication between the catabolic pathway and the regulatory elements, act together at transcriptional and posttranscriptional levels to optimize tetralin biodegradation gene expression to the environmental conditions. [ABSTRACT FROM AUTHOR]

Sphingomonads comprises a group of interesting aerobic bacteria because of their ubiquity and metabolic capability of degrading many recalcitrant contaminants. The tetralin-degrader Sphingopyxis granuli strain TFA has been recently reported as able to anaerobically grow using nitrate as the alternative electron acceptor and so far is the only bacterium with this ability within the sphingomonads group. To understand how strain TFA thrives under anoxic conditions, a differential transcriptomic analysis while growing under aerobic or anoxic conditions was performed. This analysis has been validated and complemented with transcription kinetics of representative genes of different functional categories. Results show an extensive change of the expression pattern of this strain in the different conditions. Consistently, the most induced operon in anoxia codes for proteases, presumably required for extensive changes in the protein profile. Besides genes that respond to lack of oxygen in other bacteria, there are a number of genes that respond to stress or to damage of macromolecules, including genes of the SOS DNA-damage response, which suggest that anoxic conditions represent a hostile environment for this bacterium. Interestingly, growth under anoxic conditions also resulted in repression of all flagellar and type IV pilin genes, which suggested that this strain shaves its appendages off while growing in anaerobiosis. [ABSTRACT FROM AUTHOR]

Introduction. The factors that influence in the practice of palliative care, determine the presentation of the procedures and it's behavior during the evaluation and the treatment of the patients, and it is recognized that the health care professionals could improve these factors. Methods: Descriptive design with a population of 92 nurses from Sabinas Hidalgo, N.L. We used a simple aleatory sample of 77 nurses. Ran it with Microsoft Excel 2010, fort the measurement of the knowledge we used the Spanish version of the Palliative Care Knowledge Test, and analyzed them with the SPSS version 23. Results: The mean percentage of correct answers identified about knowledge of palliative care and the total sample was 35% (SD=15), Conclusion: The result identified is considered low. [ABSTRACT FROM AUTHOR]

Background: Sphingomonads are Alphaproteobacteria that belong to the Sphingomonas, Novosphingobium, Sphingopyxis or Sphingobium genera, They are physiologically diverse and broadly distributed in nature, playing important roles in oligotrophic environments and in the degradation of recalcitrant polyaromatic compounds, Sphingopyxis is a poorly studied genus of which only one representative (S. alaskensis RB2256) has been deeply characterized. In this paper we analyze the genomic features of S. granuli strain TFA (formerly Sphingomonas macrogoltabida) in comparison with the available Sphingopyxis sequenced genomes, to describe common characteristics of this genus and to highlight unique characteristics of strain TFA. Results: The TFA genome has been assembled in a single circular chromosome of 4.7 Mb. Genomic sequence analysis and proteome comparison re-assigned the TFA strain to the Sphingopyxis genus and the S. granuli species. Some regions of the TFA genome show high similarity (ca. 100 %) to other bacteria and several genomic islands have been detected. Pathways for aromatic compound degradation have been predicted but no growth of TFA has been detected using these as carbon or nitrogen sources. Genes for nitrate respiration have been identified as TFA exclusive. Experimental data on anaerobic growth of TFA using nitrate as a terminal electron acceptor are also provided. Conclusions: Sphingopyxis representatives form a compact phylogenetic group (with the exception of S. baekryungensis DSM 16222) that share several characteristics, such as being naturally resistant to streptomycin, having only one ribosomal operon, a low number of prophages and CRISPR sequences, absence of selenoproteins and presence of ectoin and other biosynthesis pathways for secondary metabolites. Moreover, the TFA genome organization shows evidence of the presence of putative integrative and conjugative elements (ICE) responsible for the acquisition of several characteristics by horizontal transfer mechanisms. Sphingopyxis representatives have been described as strict aerobes but anaerobic growth using nitrate as a terminal electron acceptor might confer an environmental advantage to the first S. granuli strain characterized at genomic level. [ABSTRACT FROM AUTHOR]

Efficient gene regulation of metabolic pathways implies that the profile of molecules inducing the pathway matches that of the molecules that are metabolized. Gratuitous induction, a well-known phenomenon in catabolic pathways, is the consequence of differences in the substrate and inducer profiles. This phenomenon is particularly evident in pathways for biodegradation of organic contaminants that can be induced by a variety of molecules similar to the real substrates. Analysis of the regulation of tetralin biodegradation genes in mutant strains with mutations that affect each component of the initial dioxygenase enzymatic complex indicated that the response of the regulatory system to potential inducers is altered differently depending on the mutated component. Based on the expression phenotypes of a number of single or double mutants, we propose a model that represents an unprecedented way of communication between a catabolic pathway and its regulatory system to prevent efficient induction by a molecule that is not a real substrate. This communication allows a better fit of the substrate and inducer profiles, thus minimizing gratuitous induction, without a requirement for optimal coevolution to match the specificity of catabolic enzymes and their regulatory systems. Modulation of the regulatory system in this way not only provides a more appropriate response to potential inducers recognized by the regulatory system but also may properly adjust the levels of gene expression to the substrate availability. [ABSTRACT FROM AUTHOR]

Previous genetic studies in Sphingomonas macrogolitabida strain TFA have established that expression of genes involved in tetralin biodegradation (thn genes) requires the function of the LysR type activator ThnR and also ThnY. Sequence comparison indicated that ThnY is homologous to bacterial oxygenase-coupled NAD(P)H-dependent ferredoxin reductases. However, ThnY showed substitutions in highly conserved positions of the pyridine nucleotide binding domain of these ferredoxin reductases. ThnY expression is co-regulated with all other genes required for tetralin biodegradation, and presumably thnY is part of the thnCA3A4RY operon. ThnY has been purified, and its biochemical and functional properties were characterized. ThnY was found to be a monomeric orange-brown iron-sulfur flavoprotein (estimated mass of 37,000 Da) containing one non-covalently attached flavin adenine dinucleotide and one plant type ferredoxin 2Fe-2S cluster, It can be efficiently reduced by dithionite, but reduction by pyridine nucleotides was very poor. Consistently, ThnY-dependent reduction of cytochrome c, ferricyanide, or 2,6-dichlorophenolindophenol using NAD(P)H as the electron donor was undetectable or very weak. The addition of ThnY to electrophoretic mobility shift assays containing ThnR and a probe bearing two thn divergent promoters resulted in a 3-fold increase in protein-DNA complex formation affinity, which indicates that ThnY directly promotes thn transcription activation by ThnR. [ABSTRACT FROM AUTHOR]