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1.
Proc Natl Acad Sci U S A ; 121(1): e2307984120, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38109563

RESUMEN

Many studies anticipate that carbon capture and sequestration (CCS) will be essential to decarbonizing the U.S. economy. However, prior work has not estimated the time required to develop, approve, and implement a geologic sequestration site in the United States. We generate such an estimate by identifying six clearance points that must be passed before a sequestration site can become operational. For each clearance point (CP), we elicit expert judgments of the time required in the form of probability distributions and then use stochastic simulation to combine and sum the results. We find that, on average, there is a 90% chance that the time required lies between 5.5 and 9.6 y, with an upper bound of 12 y. Even using the most optimistic expert judgements, the lower bound on time is 2.7 y, and the upper bound is 8.3 y. Using the most pessimistic judgements, the lower bound is 3.5 y and the upper bound is 19.2 y. These estimates suggest that strategies must be found to safely accelerate the process. We conclude the paper by discussing seven potential strategies.

2.
Proc Natl Acad Sci U S A ; 120(25): e2218049120, 2023 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-37307471

RESUMEN

Environmental hypoxia challenges female reproductive physiology in placental mammals, increasing rates of gestational complications. Adaptation to high elevation has limited many of these effects in humans and other mammals, offering potential insight into the developmental processes that lead to and protect against hypoxia-related gestational complications. However, our understanding of these adaptations has been hampered by a lack of experimental work linking the functional, regulatory, and genetic underpinnings of gestational development in locally adapted populations. Here, we dissect high-elevation adaptation in the reproductive physiology of deer mice (Peromyscus maniculatus), a rodent species with an exceptionally broad elevational distribution that has emerged as a model for hypoxia adaptation. Using experimental acclimations, we show that lowland mice experience pronounced fetal growth restriction when challenged with gestational hypoxia, while highland mice maintain normal growth by expanding the compartment of the placenta that facilitates nutrient and gas exchange between gestational parent and fetus. We then use compartment-specific transcriptome analyses to show that adaptive structural remodeling of the placenta is coincident with widespread changes in gene expression within this same compartment. Genes associated with fetal growth in deer mice significantly overlap with genes involved in human placental development, pointing to conserved or convergent pathways underlying these processes. Finally, we overlay our results with genetic data from natural populations to identify candidate genes and genomic features that contribute to these placental adaptations. Collectively, these experiments advance our understanding of adaptation to hypoxic environments by revealing physiological and genetic mechanisms that shape fetal growth trajectories under maternal hypoxia.


Asunto(s)
Peromyscus , Placenta , Embarazo , Humanos , Animales , Femenino , Aclimatación , Desarrollo Fetal , Hipoxia
3.
Proc Natl Acad Sci U S A ; 119(14): e2118574119, 2022 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-35357968

RESUMEN

For many vertebrates, a single genetic locus initiates a cascade of developmental sex differences in the gonad and throughout the organism, resulting in adults with two phenotypically distinct sexes. Species with polygenic sex determination (PSD) have multiple interacting sex determination alleles segregating within a single species, allowing for more than two genotypic sexes and scenarios where sex genotype at a given locus can be decoupled from gonadal sex. Here we investigate the effects of PSD on secondary sexual characteristics in the cichlid fish Metriaclima mbenjii, where one female (W) and one male (Y) sex determination allele interact to produce siblings with four possible sex classes: ZZXX females, ZWXX females, ZWXY females, and ZZXY males. We find that PSD in M. mbenjii produces an interplay of sex linkage and sex limitation resulting in modular variation in morphological and behavioral traits. Further, the evolution or introgression of a newly acquired sex determiner creates additional axes of phenotypic variation for varied traits, including genital morphology, craniofacial morphology, gastrointestinal morphology, and home tank behaviors. In contrast to single-locus sex determination, which broadly results in sexual dimorphism, polygenic sex determination can induce higher-order sexual polymorphism. The modularity of secondary sexual characteristics produced by PSD provides context for understanding the evolutionary causes and consequences of maintenance, gain, or loss of sex determination alleles in populations.


Asunto(s)
Cíclidos , Procesos de Determinación del Sexo , Animales , Cíclidos/genética , Cíclidos/fisiología , Femenino , Aptitud Genética , Masculino , Fenotipo , Polimorfismo Genético , Caracteres Sexuales , Cromosomas Sexuales/genética
4.
Mol Ecol ; : e17303, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38411307

RESUMEN

Gene expression has a key role in reproductive isolation, and studies of hybrid gene expression have identified mechanisms causing hybrid sterility. Here, we review the evidence for altered gene expression following hybridization and outline the mechanisms shown to contribute to altered gene expression in hybrids. Transgressive gene expression, transcending that of both parental species, is pervasive in early generation sterile hybrids, but also frequently observed in viable, fertile hybrids. We highlight studies showing that hybridization can result in transgressive gene expression, also in established hybrid lineages or species. Such extreme patterns of gene expression in stabilized hybrid taxa suggest that altered hybrid gene expression may result in hybridization-derived evolutionary novelty. We also conclude that while patterns of misexpression in hybrids are well documented, the understanding of the mechanisms causing misexpression is lagging. We argue that jointly assessing differences in cell composition and cell-specific changes in gene expression in hybrids, in addition to assessing changes in chromatin and methylation, will significantly advance our understanding of the basis of altered gene expression. Moreover, uncovering to what extent evolution of gene expression results in altered expression for individual genes, or entire networks of genes, will advance our understanding of how selection moulds gene expression. Finally, we argue that jointly studying the dual roles of altered hybrid gene expression, serving both as a mechanism for reproductive isolation and as a substrate for hybrid ecological adaptation, will lead to significant advances in our understanding of the evolution of gene expression.

5.
Inorg Chem ; 63(4): 1938-1946, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38232376

RESUMEN

The production of ceramics from uranium coordination compounds can be achieved through thermal processing if an excess amount of the desired atoms (i.e., C or N), or reactive gaseous products (e.g., methane or nitrogen oxide) is made available to the reactive uranium metal core via decomposition/fragmentation of the surrounding ligand groups. Here, computational thermodynamic approaches were utilized to identify the temperatures necessary to produce uranium metal from some starting compounds─UI4(TMEDA)2, UCl4(TMEDA)2, UCl3(pyridine)x, and UI3(pyridine)4. Experimentally, precursors were irradiated by a laser under various gaseous environments (argon, nitrogen, and methane) creating extreme reaction conditions (i.e., fast heating, high temperature profile >2000 °C, and rapid cooling). Despite the fast dynamics associated with laser irradiation, the central uranium atom reacted with the thermal decomposition products of the ligands yielding uranium ceramics. Residual gas analysis identified vaporized products from the laser irradiation, and the final ceramic products were characterized by powder X-ray diffraction. The composition of the uranium precursor as well as the gaseous environment had a direct impact on the production of the final phases.

6.
Pain Med ; 25(2): 131-138, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37738606

RESUMEN

BACKGROUND: Virtual psychotherapy for chronic pain (CP) has been shown to be feasible, efficacious, and acceptable; however, little is known about how virtual delivery of group psychotherapy affects participants' experiences. This study aimed to explore the impact of a virtual medium during the coronavirus disease 2019 (COVID-19) pandemic on social interactions and therapeutic processes in the context of group psychotherapy for CP management. METHODS: This qualitative, interview-based study collected data on 18 individuals who participated in virtual group psychotherapy in a tertiary care pain management unit. RESULTS: Results of the thematic analysis showed 4 themes. First, the ability to participate and connect was modified by not meeting in person. Connections also occurred differently as the usual patterns of interactions changed. Participants described important shifts in how emotions are communicated and subsequent experience of empathy. Finally, the commonality of chronic pain experience was identified as a central driver of connection between participants. CONCLUSIONS: Mixed impacts of the virtual medium on group psychotherapy dynamics and processes were found. Future research could explore ways to mitigate the negative impacts.


Asunto(s)
Dolor Crónico , Psicoterapia de Grupo , Humanos , Dolor Crónico/terapia , Dolor Crónico/psicología , Psicoterapia/métodos , Emociones , Empatía
7.
Lancet ; 399(10319): 25-35, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34942103

RESUMEN

BACKGROUND: Reports suggest that COVID-19 vaccine effectiveness is decreasing, but whether this reflects waning or new SARS-CoV-2 variants-especially delta (B.1.617.2)-is unclear. We investigated the association between time since two doses of ChAdOx1 nCoV-19 vaccine and risk of severe COVID-19 outcomes in Scotland (where delta was dominant), with comparative analyses in Brazil (where delta was uncommon). METHODS: In this retrospective, population-based cohort study in Brazil and Scotland, we linked national databases from the EAVE II study in Scotland; and the COVID-19 Vaccination Campaign, Acute Respiratory Infection Suspected Cases, and Severe Acute Respiratory Infection/Illness datasets in Brazil) for vaccination, laboratory testing, clinical, and mortality data. We defined cohorts of adults (aged ≥18 years) who received two doses of ChAdOx1 nCoV-19 and compared rates of severe COVID-19 outcomes (ie, COVID-19 hospital admission or death) across fortnightly periods, relative to 2-3 weeks after the second dose. Entry to the Scotland cohort started from May 19, 2021, and entry to the Brazil cohort started from Jan 18, 2021. Follow-up in both cohorts was until Oct 25, 2021. Poisson regression was used to estimate rate ratios (RRs) and vaccine effectiveness, with 95% CIs. FINDINGS: 1 972 454 adults received two doses of ChAdOx1 nCoV-19 in Scotland and 42 558 839 in Brazil, with longer follow-up in Scotland because two-dose vaccination began earlier in Scotland than in Brazil. In Scotland, RRs for severe COVID-19 increased to 2·01 (95% CI 1·54-2·62) at 10-11 weeks, 3·01 (2·26-3·99) at 14-15 weeks, and 5·43 (4·00-7·38) at 18-19 weeks after the second dose. The pattern of results was similar in Brazil, with RRs of 2·29 (2·01-2·61) at 10-11 weeks, 3·10 (2·63-3·64) at 14-15 weeks, and 4·71 (3·83-5·78) at 18-19 weeks after the second dose. In Scotland, vaccine effectiveness decreased from 83·7% (95% CI 79·7-87·0) at 2-3 weeks, to 75·9% (72·9-78·6) at 14-15 weeks, and 63·7% (59·6-67·4) at 18-19 weeks after the second dose. In Brazil, vaccine effectiveness decreased from 86·4% (85·4-87·3) at 2-3 weeks, to 59·7% (54·6-64·2) at 14-15 weeks, and 42·2% (32·4-50·6) at 18-19 weeks. INTERPRETATION: We found waning vaccine protection of ChAdOx1 nCoV-19 against COVID-19 hospital admissions and deaths in both Scotland and Brazil, this becoming evident within three months of the second vaccine dose. Consideration needs to be given to providing booster vaccine doses for people who have received ChAdOx1 nCoV-19. FUNDING: UK Research and Innovation (Medical Research Council), Scottish Government, Research and Innovation Industrial Strategy Challenge Fund, Health Data Research UK, Fiocruz, Fazer o Bem Faz Bem Programme; Conselho Nacional de Desenvolvimento Científico e Tecnológico, Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro. TRANSLATION: For the Portuguese translation of the abstract see Supplementary Materials section.


Asunto(s)
Vacunas contra la COVID-19/administración & dosificación , COVID-19/mortalidad , COVID-19/prevención & control , ChAdOx1 nCoV-19/administración & dosificación , Eficacia de las Vacunas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Brasil , Femenino , Hospitalización , Humanos , Inmunización Secundaria , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , SARS-CoV-2/inmunología , Escocia/epidemiología , Factores de Tiempo , Vacunación
8.
Mol Ecol ; 32(14): 3975-3988, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37161914

RESUMEN

Divergence in body shape is one of the most widespread and repeated patterns of morphological variation in fishes and is associated with habitat specification and swimming mechanics. Such ecological diversification is the first stage of the explosive adaptive radiation of cichlid fishes in the East African Rift Lakes. We use two hybrid crosses of cichlids (Metriaclima sp. × Aulonocara sp. and Labidochromis sp. × Labeotropheus sp., >975 animals total) to determine the genetic basis of body shape diversification that is similar to benthic-pelagic divergence across fishes. Using a series of both linear and geometric shape measurements, we identified 34 quantitative trait loci (QTL) that underlie various aspects of body shape variation. These QTL are spread throughout the genome, each explaining 3.2-8.6% of phenotypic variation, and are largely modular. Further, QTL are distinct both between these two crosses of Lake Malawi cichlids and compared to previously identified QTL for body shape in fishes such as sticklebacks. We find that body shape is controlled by many genes of small effect. In all, we find that convergent body shape phenotypes commonly observed across fish clades are most likely due to distinct genetic and molecular mechanisms.


Asunto(s)
Cíclidos , Somatotipos , Animales , Sitios de Carácter Cuantitativo/genética , Ecosistema , Fenotipo , Lagos
9.
PLoS Med ; 19(2): e1003927, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35192598

RESUMEN

BACKGROUND: Several countries restricted the administration of ChAdOx1 to older age groups in 2021 over safety concerns following case reports and observed versus expected analyses suggesting a possible association with cerebral venous sinus thrombosis (CVST). Large datasets are required to precisely estimate the association between Coronavirus Disease 2019 (COVID-19) vaccination and CVST due to the extreme rarity of this event. We aimed to accomplish this by combining national data from England, Scotland, and Wales. METHODS AND FINDINGS: We created data platforms consisting of linked primary care, secondary care, mortality, and virological testing data in each of England, Scotland, and Wales, with a combined cohort of 11,637,157 people and 6,808,293 person years of follow-up. The cohort start date was December 8, 2020, and the end date was June 30, 2021. The outcome measure we examined was incident CVST events recorded in either primary or secondary care records. We carried out a self-controlled case series (SCCS) analysis of this outcome following first dose vaccination with ChAdOx1 and BNT162b2. The observation period consisted of an initial 90-day reference period, followed by a 2-week prerisk period directly prior to vaccination, and a 4-week risk period following vaccination. Counts of CVST cases from each country were tallied, then expanded into a full dataset with 1 row for each individual and observation time period. There was a combined total of 201 incident CVST events in the cohorts (29.5 per million person years). There were 81 CVST events in the observation period among those who a received first dose of ChAdOx1 (approximately 16.34 per million doses) and 40 for those who received a first dose of BNT162b2 (approximately 12.60 per million doses). We fitted conditional Poisson models to estimate incidence rate ratios (IRRs). Vaccination with ChAdOx1 was associated with an elevated risk of incident CVST events in the 28 days following vaccination, IRR = 1.93 (95% confidence interval (CI) 1.20 to 3.11). We did not find an association between BNT162b2 and CVST in the 28 days following vaccination, IRR = 0.78 (95% CI 0.34 to 1.77). Our study had some limitations. The SCCS study design implicitly controls for variables that are constant over the observation period, but also assumes that outcome events are independent of exposure. This assumption may not be satisfied in the case of CVST, firstly because it is a serious adverse event, and secondly because the vaccination programme in the United Kingdom prioritised the clinically extremely vulnerable and those with underlying health conditions, which may have caused a selection effect for individuals more prone to CVST. Although we pooled data from several large datasets, there was still a low number of events, which may have caused imprecision in our estimates. CONCLUSIONS: In this study, we observed a small elevated risk of CVST events following vaccination with ChAdOx1, but not BNT162b2. Our analysis pooled information from large datasets from England, Scotland, and Wales. This evidence may be useful in risk-benefit analyses of vaccine policies and in providing quantification of risks associated with vaccination to the general public.


Asunto(s)
Vacuna BNT162 , COVID-19/prevención & control , ChAdOx1 nCoV-19 , SARS-CoV-2/patogenicidad , Trombosis de los Senos Intracraneales/etiología , Adulto , Anciano , Vacuna BNT162/efectos adversos , Vacunas contra la COVID-19/efectos adversos , Estudios de Casos y Controles , ChAdOx1 nCoV-19/efectos adversos , Estudios de Cohortes , Humanos , Masculino , Persona de Mediana Edad , Reino Unido , Vacunación/estadística & datos numéricos , Gales
10.
Lancet ; 397(10285): 1646-1657, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33901420

RESUMEN

BACKGROUND: The BNT162b2 mRNA (Pfizer-BioNTech) and ChAdOx1 nCoV-19 (Oxford-AstraZeneca) COVID-19 vaccines have shown high efficacy against disease in phase 3 clinical trials and are now being used in national vaccination programmes in the UK and several other countries. Studying the real-world effects of these vaccines is an urgent requirement. The aim of our study was to investigate the association between the mass roll-out of the first doses of these COVID-19 vaccines and hospital admissions for COVID-19. METHODS: We did a prospective cohort study using the Early Pandemic Evaluation and Enhanced Surveillance of COVID-19-EAVE II-database comprising linked vaccination, primary care, real-time reverse transcription-PCR testing, and hospital admission patient records for 5·4 million people in Scotland (about 99% of the population) registered at 940 general practices. Individuals who had previously tested positive were excluded from the analysis. A time-dependent Cox model and Poisson regression models with inverse propensity weights were fitted to estimate effectiveness against COVID-19 hospital admission (defined as 1-adjusted rate ratio) following the first dose of vaccine. FINDINGS: Between Dec 8, 2020, and Feb 22, 2021, a total of 1 331 993 people were vaccinated over the study period. The mean age of those vaccinated was 65·0 years (SD 16·2). The first dose of the BNT162b2 mRNA vaccine was associated with a vaccine effect of 91% (95% CI 85-94) for reduced COVID-19 hospital admission at 28-34 days post-vaccination. Vaccine effect at the same time interval for the ChAdOx1 vaccine was 88% (95% CI 75-94). Results of combined vaccine effects against hospital admission due to COVID-19 were similar when restricting the analysis to those aged 80 years and older (83%, 95% CI 72-89 at 28-34 days post-vaccination). INTERPRETATION: Mass roll-out of the first doses of the BNT162b2 mRNA and ChAdOx1 vaccines was associated with substantial reductions in the risk of hospital admission due to COVID-19 in Scotland. There remains the possibility that some of the observed effects might have been due to residual confounding. FUNDING: UK Research and Innovation (Medical Research Council), Research and Innovation Industrial Strategy Challenge Fund, Health Data Research UK.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19/prevención & control , Hospitalización/estadística & datos numéricos , Vacunación Masiva , Pandemias/prevención & control , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Vacuna BNT162 , COVID-19/epidemiología , ChAdOx1 nCoV-19 , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Escocia/epidemiología , Clase Social , Adulto Joven
11.
Thorax ; 77(5): 497-504, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34782484

RESUMEN

BACKGROUND: The QCovid algorithm is a risk prediction tool that can be used to stratify individuals by risk of COVID-19 hospitalisation and mortality. Version 1 of the algorithm was trained using data covering 10.5 million patients in England in the period 24 January 2020 to 30 April 2020. We carried out an external validation of version 1 of the QCovid algorithm in Scotland. METHODS: We established a national COVID-19 data platform using individual level data for the population of Scotland (5.4 million residents). Primary care data were linked to reverse-transcription PCR (RT-PCR) virology testing, hospitalisation and mortality data. We assessed the performance of the QCovid algorithm in predicting COVID-19 hospitalisations and deaths in our dataset for two time periods matching the original study: 1 March 2020 to 30 April 2020, and 1 May 2020 to 30 June 2020. RESULTS: Our dataset comprised 5 384 819 individuals, representing 99% of the estimated population (5 463 300) resident in Scotland in 2020. The algorithm showed good calibration in the first period, but systematic overestimation of risk in the second period, prior to temporal recalibration. Harrell's C for deaths in females and males in the first period was 0.95 (95% CI 0.94 to 0.95) and 0.93 (95% CI 0.92 to 0.93), respectively. Harrell's C for hospitalisations in females and males in the first period was 0.81 (95% CI 0.80 to 0.82) and 0.82 (95% CI 0.81 to 0.82), respectively. CONCLUSIONS: Version 1 of the QCovid algorithm showed high levels of discrimination in predicting the risk of COVID-19 hospitalisations and deaths in adults resident in Scotland for the original two time periods studied, but is likely to need ongoing recalibration prospectively.


Asunto(s)
COVID-19 , Adulto , Algoritmos , Calibración , Estudios de Cohortes , Femenino , Hospitalización , Humanos , Masculino , Escocia/epidemiología
12.
Inorg Chem ; 61(44): 17579-17589, 2022 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-36269886

RESUMEN

UI4(1,4-dioxane)2 was subjected to laser-based heating─a method that enables localized, fast heating (T > 2000 °C) and rapid cooling under controlled conditions (scan rate, power, atmosphere, etc.)─to understand its thermal decomposition. A predictive computational thermodynamic technique estimated the decomposition temperature of UI4(1,4-dioxane)2 to uranium (U) metal to be 2236 °C, a temperature achievable under laser irradiation. Dictated by the presence of reactive, gaseous byproducts, the thermal decomposition of UI4(1,4-dioxane)2 under furnace conditions up to 600 °C revealed the formation of UO2, UIx, and U(C1-xOx)y, while under laser irradiation, UI4(1,4-dioxane)2 decomposed to UO2, U(C1-xOx)y, UC2-zOz, and UC. Despite the fast dynamics associated with laser irradiation, the central uranium atom reacted with the thermal decomposition products of the ligand (1,4-dioxane = C4H8O2) instead of producing pure U metal. The results highlight the potential to co-develop uranium precursors with specific irradiation procedures to advance nuclear materials research by finding new pathways to produce uranium carbide.

13.
Environ Sci Technol ; 55(13): 8806-8816, 2021 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-34167293

RESUMEN

Biodiversity is declining at an alarming rate globally, with freshwater ecosystems particularly threatened. Field-based correlational studies have "ranked" stressors according to their relative effects on freshwater biota, however, supporting cause-effect data from laboratory exposures are lacking. Here, we designed exposures to elicit chronic effects over equivalent exposure ranges for three ubiquitous stressors (temperature: 22-28 °C; pollution [14 component mixture]: 0.05-50 µg/L; invasive predator cue [signal crayfish, Pacifasticus leniusculus]: 25-100% cue) and investigated effects on physiological end points in the pond snail (Lymnaeastagnalis). All stressors reduced posthatch survival at their highest exposure levels, however, highly divergent effects were observed at lower test levels. Temperature stimulated hatching, growth, and reproduction, whereas pollution delayed hatching, decreased growth, reduced egg number/embryo viability, and induced avoidance behavior. The invasive predator cue stimulated growth and reduced embryo viability. In agreement with field-based ranking of stressors, pollution was identified as having the most severe effects in our test system. We demonstrate here the utility of laboratory studies to effectively determine hierarchy of stressors according to their likelihood of causing harm in the field, which has importance for conservation. Finally, we report negative impacts on life-history traits central to population stability (survival/reproduction) at the lowest pollution level tested (0.05 µg/L).


Asunto(s)
Laboratorios , Lymnaea , Animales , Ecosistema , Agua Dulce , Caracoles
14.
J Couns Psychol ; 68(1): 88-97, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32352824

RESUMEN

Adopting a self-determination theory perspective, this 3-wave longitudinal study explores the role of perfectionism in goal pursuit and the experience of depressive symptoms. The findings highlight the role of goal-related autonomy in mediating the opposite effects of self-critical and personal standards perfectionism on goal progress and depressive symptoms over the course of an academic year. The results suggest a way of understanding the pathway to depressive symptoms and poor goal progress in perfectionists. They point to a number of implications for clinical practice when working with self-critical perfectionists. Specifically, they indicate that interventions aimed at promoting autonomous motivation, may not only bolster goal progress but also act as a protective factor against depressive symptoms. Together, the results indicate that autonomous motivation is central to goal progress and suggest that low goal-related autonomy can be linked to negative outcomes. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Asunto(s)
Depresión/psicología , Depresión/terapia , Objetivos , Motivación , Perfeccionismo , Autonomía Personal , Adolescente , Adulto , Depresión/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Motivación/fisiología , Adulto Joven
15.
Matern Child Nutr ; 17(1): e13069, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32770664

RESUMEN

In many low-income countries, such as Burkina Faso, rates of malnutrition are high among children. Research indicates that animal source foods may provide important elements to improve growth and development of young children, especially during periods of rapid development, such as the first 1,000 days of life. The Un Oeuf study is designed to test an innovative behaviour change communication strategy to increase egg consumption in children 6-24 months in Burkina Faso, thereby improving dietary diversity and nutritional outcomes. This 1-year cluster randomised controlled trial tests whether the gifting of chickens by a community champion directly to a child, combined with a behaviour change package of integrated poultry management and human nutrition trainings, can significantly increase egg consumption among children under 2 years in rural communities where egg consumption is very low. The nutrition-sensitive behaviour change package is designed to increase egg consumption through improving livestock production, women's empowerment and food security at the household level. This paper presents a detailed account of the study design and protocol for the Un Oeuf study, alongside a description of the study population. Baseline data show a study population with high rates of malnutrition (stunting 21.6%, wasting 10.8% and underweight 20.4%) and a very low rate of egg consumption-less than 10% among children. Although poultry production is quite common, egg consumption is low reportedly because of cultural norms, including widespread practice of allowing eggs to hatch and a lack of knowledge about the nutritional benefits of egg consumption.


Asunto(s)
Pollos , Desnutrición , Animales , Burkina Faso/epidemiología , Niño , Preescolar , Huevos , Femenino , Humanos , Lactante , Desnutrición/epidemiología , Desnutrición/prevención & control , Estado Nutricional
16.
J Cell Sci ; 131(16)2018 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-30002136

RESUMEN

Although Prx1 (also known as PRRX1)-expressing cells and their primary cilia are critical for embryonic development, they have yet to be studied in the context of postnatal skeletogenesis owing to the lethality of mouse models. A tamoxifen-inducible Prx1 model has been developed, and we determined that expression directed by this promoter is highly restricted to the cambium layers in the periosteum and perichondrium after birth. To determine the postnatal role of these cambium layer osteochondroprogenitors (CLOPs) and their primary cilia, we developed models to track the fate of CLOPs (Prx1CreER-GFP;Rosa26tdTomato) and selectively disrupt their cilia (Prx1CreER-GFP;Ift88fl/fl). Our tracking studies revealed that CLOPs populate cortical and trabecular bone, the growth plate and secondary ossification centers during the normal program of postnatal skeletogenesis. Furthermore, animals lacking CLOP cilia exhibit stunted limb growth due to disruptions in endochondral and intramembranous ossification. Histological examination indicates that growth is stunted due to limited differentiation, proliferation and/or abnormal hypertrophic differentiation in the growth plate. Collectively, our results suggest that CLOPs are programmed to rapidly populate distant tissues and produce bone via a primary cilium-mediated mechanism in the postnatal skeleton.


Asunto(s)
Desarrollo Óseo/fisiología , Condrogénesis/genética , Cilios/fisiología , Proteínas de Homeodominio/genética , Osteogénesis/genética , Células Madre/fisiología , Animales , Animales Recién Nacidos/crecimiento & desarrollo , Desarrollo Óseo/genética , Diferenciación Celular/genética , Condrocitos/fisiología , Femenino , Placa de Crecimiento/citología , Placa de Crecimiento/metabolismo , Proteínas de Homeodominio/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Osteoblastos/fisiología , Periostio/citología , Periostio/metabolismo , Embarazo , Células Madre/metabolismo
17.
J Neuroeng Rehabil ; 17(1): 41, 2020 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-32138747

RESUMEN

BACKGROUND: There is scientific evidence that older adults aged 65 and over walk with increased step width variability which has been associated with risk of falling. However, there are presently no threshold levels that define the optimal reference range of step width variability. Thus, the purpose of our study was to estimate the optimal reference range for identifying older adults with normative and excessive step width variability. METHODS: We searched systematically the BMC, Cochrane Library, EBSCO, Frontiers, IEEE, PubMed, Scopus, SpringerLink, Web of Science, Wiley, and PROQUEST databases until September 2018, and included the studies that measured step width variability in both younger and older adults during walking at self-selected speed. Data were pooled in meta-analysis, and standardized mean differences (SMD) with 95% confidence intervals (CI) were calculated. A single-decision threshold method based on the Youden index, and a two-decision threshold method based on the uncertain interval method were used to identify the optimal threshold levels (PROSPERO registration: CRD42018107079). RESULTS: Ten studies were retrieved (older adults = 304; younger adults = 219). Step width variability was higher in older than in younger adults (SMD = 1.15, 95% CI = 0.60; 1.70; t = 4.72, p = 0.001). The single-decision method set the threshold level for excessive step width variability at 2.14 cm. For the two-decision method, step width variability values above the upper threshold level of 2.50 cm were considered excessive, while step width variability values below the lower threshold level of 1.97 cm were considered within the optimal reference range. CONCLUSION: Step width variability is higher in older adults than in younger adults, with step width variability values above the upper threshold level of 2.50 cm to be considered as excessive. This information could potentially impact rehabilitation technology design for devices targeting lateral stability during walking.


Asunto(s)
Envejecimiento/fisiología , Marcha/fisiología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Adulto Joven
18.
J Insect Sci ; 20(4)2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32610346

RESUMEN

The use of insecticides has been a central approach to control disease-transmitting mosquitoes for the last century. The high prevalence of pyrethroid use as public health insecticides has resulted in the evolution of pyrethroid resistance in many populations of Aedes aegypti (Linnaeus) (Diptera: Culicidae), throughout its global distribution range. Insecticide resistance is often correlated with an associated fitness cost. In this project, we studied the phenotypes of hybrid mosquitoes derived from crossing a pyrethroid-resistant strain of Ae. aegypti (Puerto Rico [PR]) with a more susceptible one (Rockefeller [ROCK]). We first sequenced and compared the para gene of both original strains. We then crossed males from one strain with females of the other, creating two hybrids (Puertofeller, Rockorico). We used a Y-tube choice assay to measure the attraction of these strains towards a human host. We then compared the levels of pyrethroid resistance in the different strains. We found three known resistance mutations in the para gene sequence of the PR strain. In our attraction assays, PR females showed lower attraction to humans, than the ROCK females. Both hybrid strains showed strong attraction to a human host. In the insecticide resistance bottle assays, both hybrid strains showed marginal increases in resistance to permethrin compared to the more susceptible ROCK strain. These results suggest that hybrids of sensitive and permethrin-resistant mosquitoes have an incremental advantage compared to more susceptible mosquitoes when challenged with permethrin. This explains the rapid spread of permethrin resistance that was observed many times in the field.


Asunto(s)
Aedes/efectos de los fármacos , Hibridación Genética , Resistencia a los Insecticidas/genética , Insecticidas/farmacología , Mosquitos Vectores/efectos de los fármacos , Permetrina/farmacología , Aedes/genética , Animales , Femenino , Mosquitos Vectores/genética
19.
Int J Psychiatry Med ; 55(2): 74-81, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31698993

RESUMEN

Objective: Meningioma is the most common type of primary central nervous system and intracranial tumor, and psychiatric changes attributed to meningioma include depression, apathy, psychosis, and personality changes. We present a case of a 59-year-old man with right parietal meningioma who developed mania with psychotic features throughout multiple hospitalizations. Method: Single-case report. Results: The patient originally presented with headache and bilateral lower extremity weakness. He was found to have a large medial sphenoidal wing meningioma and a small right parietal meningioma. The sphenoidal wing meningioma was removed via craniotomy, but the right parietal meningioma was not resected. In the following years, the patient developed symptoms of mania and psychosis which coincided with an increase in size of the right parietal meningioma. Conclusions: Previous studies have linked right parietal meningioma to psychosis, but this case is one of the first to suggest that right parietal meningioma may be associated with the development of mania along with psychotic features.


Asunto(s)
Trastorno Bipolar/etiología , Neoplasias Meníngeas/complicaciones , Meningioma/complicaciones , Lóbulo Parietal/diagnóstico por imagen , Trastornos Psicóticos/etiología , Trastorno Bipolar/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Neoplasias Meníngeas/diagnóstico por imagen , Meningioma/diagnóstico por imagen , Persona de Mediana Edad , Trastornos Psicóticos/diagnóstico por imagen
20.
BMC Evol Biol ; 19(1): 85, 2019 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-30995908

RESUMEN

BACKGROUND: Color and pattern phenotypes have clear implications for survival and reproduction in many species. However, the mechanisms that produce this coloration are still poorly characterized, especially at the genomic level. Here we have taken a transcriptomics-based approach to elucidate the underlying genetic mechanisms affecting color and pattern in a highly polytypic poison frog. We sequenced RNA from the skin from four different color morphs during the final stage of metamorphosis and assembled a de novo transcriptome. We then investigated differential gene expression, with an emphasis on examining candidate color genes from other taxa. RESULTS: Overall, we found differential expression of a suite of genes that control melanogenesis, melanocyte differentiation, and melanocyte proliferation (e.g., tyrp1, lef1, leo1, and mitf) as well as several differentially expressed genes involved in purine synthesis and iridophore development (e.g., arfgap1, arfgap2, airc, and gart). CONCLUSIONS: Our results provide evidence that several gene networks known to affect color and pattern in vertebrates play a role in color and pattern variation in this species of poison frog.


Asunto(s)
Anuros/genética , Regulación de la Expresión Génica , Pigmentación de la Piel/genética , Animales , Color , Ontología de Genes , Melaninas/metabolismo , Fenotipo , Análisis de Componente Principal , Transcriptoma/genética
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