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1.
BMC Med Educ ; 24(1): 182, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38395856

RESUMEN

BACKGROUND: As physician distress rises, medical schools must provide programs to counter such distress at the earliest stages of training. Mindfulness training (MT) is one intervention that can alleviate stress during medical school. However, framing MT around wellness alone misses the opportunity to connect core cognitive and psychological capacities strengthened by MT to professional goals and skill acquisition inherent to successful medical training. Here, we highlight how the attentional components of MT align with students' goals of becoming attending physicians while promoting academic, psychological, and interpersonal flourishing. MT courses that focus on strengthening attentional capacities can intuitively link academic and professional development with wellness, appealing to a wide array of students. METHODS: We iteratively recontextualized an existing short-form mindfulness training program for high-stress pre-professionals, known as Mindfulness Based Attention Training (MBAT), to the medical school context (MBAT-Rx). MBAT-Rx was offered by physician trainers to first-year medical students at Warren Alpert Medical School of Brown University as a tool for improving study habits and focus in addition to the development of both self-care and patient care strategies. MBAT-Rx consists of weekly, two-hour sessions over four weeks, with 10-15 min of daily mindfulness practice between sessions. At the end of the four weeks, students submitted voluntary program evaluation responses detailing their experience of the program. RESULTS: Optional program evaluation responses (n = 67) highlight that students found the program to be useful for their academic success and ability to pay attention, their interpersonal relationships, and their psychological health. By framing MT as an opportunity to boost core attentional capacities and connecting this to professional and academic goals in addition to wellness, MBAT-Rx appealed to a wide variety of students. CONCLUSIONS: Our ongoing work suggests that framing MT as both a professional development and wellness promotion tool, taught by physicians themselves, and structured around students' time demands, may be a successful model for medical schools looking to increase the impact of their mindfulness offerings. Such programs are needed to equip medical students to navigate the demands of a challenging healthcare training landscape.


Asunto(s)
Atención Plena , Estudiantes de Medicina , Humanos , Estudiantes de Medicina/psicología , Profesionalismo , Evaluación de Programas y Proyectos de Salud , Docentes , Estrés Psicológico/psicología
2.
Microbiol Resour Announc ; 13(4): e0109423, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38411068

RESUMEN

Organism abundance and diversity were assessed in Lake Erie ice samples using sequences derived from a combined metagenomic and metatranscriptomic analysis. The 68,417 unique sequences were from Bacteria (77.5%), Eukarya (22.3%), and Archaea (0.2%) and indicated diverse species of organisms from 32 bacterial, 8 eukaryotic, and 2 archaeal taxonomic groups.

3.
Aging Ment Health ; 28(1): 130-141, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37702364

RESUMEN

OBJECTIVES: The COVID-19 pandemic drastically accelerated the need for studies examining the effectiveness of programs to bolster psychological well-being, particularly for at-risk groups, such as older adults (OAs). Mindfulness Training (MT) has been suggested as a well-suited program for this purpose. The present study examined the impact of a 4-week online, trainer-led MT course tailored for OAs during the early months of the COVID-19 pandemic. METHODS: Fifty-three OAs were randomly assigned to either Group A or Group B. Group A received the online MT course during the 4-week interval between the first (T1) and second (T2) testing sessions, while Group B received the same MT course during the interval between T2 and the third testing session (T3). The testing sessions included measures of mindfulness, emotional well-being, psychological health, and cognitive performance. In addition, a very brief survey was sent every week during the T1-T2 and T2-T3 intervals to assess weekly emotional well-being. RESULTS: The findings revealed that MT may improve some, albeit not all, aspects of mindfulness and well-being, while no significant results were noted for outcomes measuring psychological health and cognitive performance. CONCLUSIONS: These findings are discussed in the context of the evolving COVID-19 situation.


Asunto(s)
COVID-19 , Atención Plena , Humanos , Anciano , Atención Plena/métodos , Pandemias , Emociones , Salud Mental
4.
Genome Biol Evol ; 15(7)2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-37341531

RESUMEN

Eukaryotic ribosomal DNA (rDNA) comprises tandem units of highly conserved coding genes separated by rapidly evolving spacer DNA. The spacers of all 12 species examined were filled with short direct repeats (DRs) and multiple long tandem repeats (TRs), completing the rDNA maps that previously contained unannotated and inadequately studied sequences. The external transcribed spacers also were filled with DRs and some contained TRs. We infer that the spacers arose from transposon insertion, followed by their imprecise excision, leaving short DRs characteristic of transposon visitation. The spacers provided a favored location for transposon insertion because they occupy loci containing hundreds to thousands of gene repeats. The spacers' primary cellular function may be to link one ribosomal RNA transcription unit to the next, whereas transposons flourish here because they have colonized the most frequently used part of the genome.


Asunto(s)
ARN Ribosómico , Secuencias Repetitivas de Ácidos Nucleicos , ADN Ribosómico/genética , ARN Ribosómico/genética , ADN Intergénico
5.
Mil Med ; 188(3-4): e761-e770, 2023 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-34557922

RESUMEN

INTRODUCTION: Mental skills such as focusing attention and managing emotions are essential for optimal performance in high-stress occupations. Studies with military samples have demonstrated that mindfulness training (MT) led to improved computer-based cognitive performance. MATERIALS AND METHODS: To examine the impact of MT on operational performance, mental skills, and psychological health, a short-form program, Mindfulness-Based Attention Training (MBAT), was delivered to active duty soldiers as part of two randomized trials. Participants in study 1 (n = 121) and study 2 (n = 77) were randomized to one of three conditions: MT with proctored practice, MT with unproctored practice, or a waitlist control. Weekly 2-hour MBAT sessions were offered to participants in both MT conditions for 4 weeks. Beyond these sessions, participants also engaged in mindfulness practice that was proctored (within the occupational context) or unproctored (left up to the individual) for four subsequent weeks. RESULTS: Overall, the frequency of mindfulness practice was generally associated with better performance and improvements in mental skills. In study 1, those who practiced 3 or more days per week performed better on marksmanship under physical stress and reported fewer attentional lapses, less emotion regulation difficulties, greater mental toughness, and higher self-reported mindfulness compared to those who did not practice. In study 2, the frequency of mindfulness practice was associated with fewer attentional lapses and emotion regulation difficulties. CONCLUSIONS: Consistent with prior findings, results suggest that regular engagement in MT practice may help to optimize operational performance and improve mental skills in military cohorts.


Asunto(s)
Atención Plena , Humanos , Atención Plena/métodos , Atención/fisiología , Emociones , Autoinforme
6.
Front Psychol ; 14: 1232598, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38213609

RESUMEN

Introduction: Mind wandering, a phenomenon in which attention drifts away from the task-at-hand, is associated with deleterious effects on performance and well-being. As such, efforts to curb mind wandering are warranted. Recently, mindfulness training (MT) has been found to protect against mind wandering. Yet, many MT programs are at risk of falling off the implementation cliff due to challenges implementing these programs in applied settings. To mitigate against this, early-stage research in small convenience samples may be necessary to spur stakeholder engagement and collaboration. Herein, the effects of MT on mind wandering were examined via an internal meta-analysis of early-stage studies of a manualized, context-adaptable short-form MT program, referred to as Mindfulness-Based Attention Training (MBAT). Methods: Five longitudinal studies (N = 304) were conducted in a variety of organizational cohorts. Self-reported mind wandering and meta-awareness, as well as accuracy (A') and response time variability (intra-individual coefficient of variation, ICV) during performance of the sustained attention to response task (SART) were assessed at baseline (T1) and 4 weeks later (T2) in MBAT and no-training participants. Results: Standardized mean change (SMC) from T1 to T2 significantly differed between MBAT and no-training groups for mind wandering (ΔSMC = -0.387, p < 0.001), meta-awareness (ΔSMC = -0.374, p < 0.001), and ICV (ΔSMC = -0.376, p = 0.043), suggesting potential protective effects in self-reported and performance-based metrics of mind wandering. Discussion: These results serve as preliminary proof-of-concept support for MBAT's protective effects on mind wandering. Further, they suggest that MBAT is amenable to implementation across a variety of applied and organizational settings and warrants additional research employing larger sample sizes in randomized controlled designs.

7.
Metabolomics ; 18(5): 29, 2022 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-35488937

RESUMEN

BACKGROUND: Through the systematic large-scale profiling of metabolites, metabolomics provides a tool for biomarker discovery and improving disease monitoring, diagnosis, prognosis, and treatment response, as well as for delineating disease mechanisms and etiology. As a downstream product of the genome and epigenome, transcriptome, and proteome activity, the metabolome can be considered as being the most proximal correlate to the phenotype. Integration of metabolomics data with other -omics data in multi-omics analyses has the potential to advance understanding of human disease development and treatment. AIM OF REVIEW: To understand the current funding and potential research opportunities for when metabolomics is used in human multi-omics studies, we cross-sectionally evaluated National Institutes of Health (NIH)-funded grants to examine the use of metabolomics data when collected with at least one other -omics data type. First, we aimed to determine what types of multi-omics studies included metabolomics data collection. Then, we looked at those multi-omics studies to examine how often grants employed an integrative analysis approach using metabolomics data. KEY SCIENTIFIC CONCEPTS OF REVIEW: We observed that the majority of NIH-funded multi-omics studies that include metabolomics data performed integration, but to a limited extent, with integration primarily incorporating only one other -omics data type. Some opportunities to improve data integration may include increasing confidence in metabolite identification, as well as addressing variability between -omics approach requirements and -omics data incompatibility.


Asunto(s)
Investigación Biomédica , Metabolómica , Metaboloma , National Institutes of Health (U.S.) , Proteoma , Estados Unidos
8.
PLoS One ; 16(4): e0250061, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33857240

RESUMEN

OBJECTIVES: Systems epidemiology approaches may lead to a better understanding of the complex and dynamic multi-level constellation of contributors to cancer risk and outcomes and help target interventions. This grant portfolio analysis aimed to describe the National Institutes of Health (NIH) and the National Cancer Institute (NCI) investments in systems epidemiology and to identify gaps in the cancer systems epidemiology portfolio. METHODS: The analysis examined grants funded (2013-2018) through seven NIH systems science Funding Opportunity Announcements (FOAs) as well as cancer-specific systems epidemiology grants funded by NCI during that same time. Study characteristics were extracted from the grant abstracts and specific aims and coded. RESULTS: Of the 137 grants awarded under the NIH FOAs, 52 (38%) included systems epidemiology. Only five (4%) were focused on cancer systems epidemiology. The NCI-wide search (N = 453 grants) identified 35 grants (8%) that included cancer systems epidemiology in their specific aims. Most of these grants examined epidemiology and surveillance-based questions (60%); fewer addressed clinical care or clinical trials (37%). Fifty-four percent looked at multiple scales within the individual (e.g., cell, tissue, organ), 49% looked beyond the individual (e.g., individual, community, population), and few (9%) included both. Across all grants examined, the systems epidemiology grants primarily focused on discovery or prediction, rather than on impacts of intervention or policy. CONCLUSIONS: The most notable finding was that grants focused on cancer versus other diseases reflected a small percentage of the portfolio, highlighting the need to encourage more cancer systems epidemiology research. Opportunities include encouraging more multiscale research and continuing the support for broad examination of domains in these studies. Finally, the nascent discipline of systems epidemiology could benefit from the creation of standard terminology and definitions to guide future progress.


Asunto(s)
Investigación Biomédica/economía , Organización de la Financiación/economía , National Institutes of Health (U.S.)/economía , Neoplasias , Apoyo a la Investigación como Asunto/economía , Humanos , Estados Unidos
9.
Cancer Epidemiol Biomarkers Prev ; 30(7): 1305-1311, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33795213

RESUMEN

BACKGROUND: The goals of this project were to assess the status of NCI's rare cancer-focused population science research managed by the Division of Cancer Control and Population Sciences (DCCPS), to develop a framework for evaluation of rare cancer research activities, and to review available resources to study rare cancers. METHODS: Cancer types with an overall age-adjusted incidence rate of less than 20 cases per 100,000 individuals were identified using NCI Surveillance, Epidemiology and End Results (SEER) Program data. SEER data were utilized to develop a framework based on statistical commonalities. A portfolio analysis of DCCPS-supported active grants and a review of three genomic databases were conducted. RESULTS: For the 45 rare cancer types included in the analysis, 123 active DCCPS-supported rare cancer-focused grants were identified, of which the highest percentage (18.7%) focused on ovarian cancer. The developed framework revealed five clusters of rare cancer types. The cluster with the highest number of grants (n = 43) and grants per cancer type (10.8) was the cluster that included cancer types of higher incidence, average to better survival, and high prevalence (in comparison with other rare cancers). Resource review revealed rare cancers are represented in available genomic resources, but to a lesser extent compared with more common cancers. CONCLUSIONS: This article provides an overview of the rare cancer-focused population sciences research landscape as well as information on gaps and opportunities. IMPACT: The findings of this article can be used to develop efficient and comprehensive strategies to accelerate rare cancer research.See related commentary by James V. Lacey Jr, p. 1300.


Asunto(s)
Investigación Biomédica/tendencias , Estudios Epidemiológicos , Neoplasias/epidemiología , Enfermedades Raras/epidemiología , Investigación Biomédica/estadística & datos numéricos , Humanos , Incidencia , National Cancer Institute (U.S.)/estadística & datos numéricos , Neoplasias/prevención & control , Prevalencia , Brechas de la Práctica Profesional/estadística & datos numéricos , Brechas de la Práctica Profesional/tendencias , Enfermedades Raras/prevención & control , Programa de VERF/estadística & datos numéricos , Tasa de Supervivencia , Estados Unidos/epidemiología
10.
Acta Biotheor ; 69(3): 343-358, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33284411

RESUMEN

Bacteria are divided primarily into monoderms (with one cell membrane, and usually Gram-positive, due to a thick peptidoglycan layer) and diderms (with two cell membranes, and mostly Gram-negative, due to a thin peptidoglycan layer sandwiched between the two membranes). Photosynthetic species are spread among the taxonomic groups, some having type I reaction centers (RCI in monoderm phylum Firmicutes; and diderm phyla Acidobacteria and Chlorobi), others with type II reaction centers (RCII in monoderm phylum Chloroflexi; and diderm taxa Gemmatimonadetes, and alpha-, beta-, and gamma-Proteobacteria), and some containing both (RCI and RCII, only in diderm phylum Cyanobacteria). In most bacterial phylograms, photosystem types and diderm taxa are polyphyletic. A more parsimonious arrangement, which is supported by photosystem evolution, as well as additional sets of molecular characters, suggests that endosymbiotic events resulted in the formation of the diderms. In the model presented, monoderms readily form a monophyletic group, while diderms are produced by at least two endosymbiotic events, followed by additional evolutionary changes.


Asunto(s)
Bacterias , Bacterias Grampositivas , Fotosíntesis , Filogenia , Simbiosis
11.
Front Immunol ; 11: 575200, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33117372

RESUMEN

Nicotine acts as a potent modulator of normal cellular responses through the nicotinic acetylcholine receptor subtype alpha7. In a mouse genetic model of alpha7 receptor dysfunction, alpha7E260A:G, 85 percent of 18 month-old mice exhibit an age-associated spontaneous loosening or complete loss of 3rd molars that was not present in the control mice. The adjacent soft tissues appeared largely unaffected. Further analysis including micro-CT revealed evidence of bone loss surrounding the 3rd molars with areas of cavitation and/or sponge-like (cancellous) bone remodeling in the mandible. The mandible microbiome was examined using 16S-rRNA sequencing. The results show the alpha7E260A:G oral microbiome included increased landscape complexity indicative of dysbiosis, and a significant increase of some bacteria, particularly Staphylococcus. These results suggest that normal alpha7 function plays a relevant role in maintaining normal gene expression and oral microbiome stasis. Consequently, this mouse model suggests there are consequences to ongoing alpha7 receptor dysfunction and oral health, as can occur from chronic exposure to nicotine as expected from electronic nicotine delivery systems (ENDS or "vaping"), that may not be seen until older age.


Asunto(s)
Bacterias/crecimiento & desarrollo , Boca/microbiología , Salud Bucal , Tabaquismo/metabolismo , Tabaquismo/microbiología , Pérdida de Diente/metabolismo , Pérdida de Diente/microbiología , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo , Factores de Edad , Animales , Bacterias/genética , Modelos Animales de Enfermedad , Disbiosis , Ratones Transgénicos , Microbiota , Boca/diagnóstico por imagen , Ribotipificación , Tabaquismo/genética , Pérdida de Diente/diagnóstico por imagen , Pérdida de Diente/genética , Microtomografía por Rayos X , Receptor Nicotínico de Acetilcolina alfa 7/genética
12.
Am J Physiol Lung Cell Mol Physiol ; 319(4): L683-L692, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32726138

RESUMEN

Nicotine of unprecedented concentrations and purity is being inhaled by those using commercially available electronic nicotine delivery systems (ENDS). The consequences of this route of self-administration on the immunological response to inhaled allergens are not known. In mice, sensitization and inhalation challenge with the common environmental house dust mite (HDM) allergen is an experimental model of this response. When mice were exposed to aerosolized nicotine base (aeroNic) twice daily, 5 days/wk for 8 wk, the HDM-induced recruitment of eosinophils (EOS) was substantially reduced as measured in bronchial alveolar lavage fluid (BALF). Oral nicotine administration had no effect. HDM challenge in the presence of nicotinic receptor subtype α7 (α7)-specific type-1 positive allosteric modulators (PAMs) was alone sufficient to suppress EOS. RNA analysis of alveolar macrophages (AM) collected from BALF after HDM challenge of aeroNic revealed that α7 activation strongly suppresses initiation of Ccl24 (eotaxin 2) transcription. To examine possible cellular signaling mechanisms coupling α7 to Ccl24 transcription, an AM culture model system was used. In AM cultures of freshly collected BALF, Ccl24 transcription was robustly activated by a mixture of IL-4 and IL-10, and this was suppressed by coapplication of type-1 PAMs through a pathway that requires p38MAPK but is independent of Jak2. These results suggest that the EOS response to HDM inhaled allergen is subject to modulation through activation of the α7 receptor and suggest that the allergic response may be substantially modified in ENDS users.


Asunto(s)
Antígenos Dermatofagoides/efectos de los fármacos , Eosinófilos/efectos de los fármacos , Pulmón/efectos de los fármacos , Nicotina/farmacología , Animales , Líquido del Lavado Bronquioalveolar/citología , Eosinófilos/metabolismo , Hipersensibilidad/tratamiento farmacológico , Hipersensibilidad/metabolismo , Pulmón/metabolismo , Ratones , Ácaros , Nicotina/metabolismo , Pyroglyphidae/efectos de los fármacos , Pyroglyphidae/inmunología
13.
Biology (Basel) ; 9(3)2020 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-32188079

RESUMEN

A combined metatranscriptomic and metagenomic study of Vostok (Antarctica) ice core sections from glacial, basal, and lake water accretion ice yielded sequences that indicated a wide variety of species and possible conditions at the base of the glacier and in subglacial Lake Vostok. Few organisms were in common among the basal ice and accretion ice samples, suggesting little transmission of viable organisms from the basal ice meltwater into the lake water. Additionally, samples of accretion ice, each of which originated from water in several locations of the shallow embayment, exhibit only small amounts of mixing of species. The western-most portion of the embayment had very low numbers of organisms, likely due to biologically challenging conditions. Increasing numbers of organisms were found progressing from west to east, up to approximately 7 km into the embayment. At that point, the numbers of unique sequences and sequence reads from thermophilic, thermotolerant, psychrophilic, and psychrotolerant organisms increased dramatically, as did sequences from alkaliphilic, alkalitolerant, acidophilic, and acidotolerant sequences. The number of unique and total sequences were positively associated with increases in concentrations of Na+, Ca2+, Mg2+, SO42-, Cl-, total amino acids, and non-purgeable organic carbon. The numbers of unique sequences from organisms reported from soil, sediment, ice, aquatic, marine, animal, and plant (probably pollen) sources also peaked in this region, suggesting that this was the most biologically active region. The confluence of the high numbers of organisms, physiologies, and metabolic capabilities suggests the presence of energy and nutrient sources in the eastern half of the embayment. Data from the main basin suggested a cold oligotrophic environment containing fewer organisms. In addition to bacteria, both the basal ice and accretion ice contained sequences from a diverse assemblage of eukaryotes, as well as from bacteria that are known to be associated with multicellular eukaryotes.

14.
Psychiatry Res ; 285: 112794, 2020 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-32078885

RESUMEN

Motivated by the growing interest in promoting resilience in first responders and other professionals who face threatening professional circumstances, the current study investigated the effectiveness of offering a short-form mindfulness training (MT) program to firefighters. The overarching question was to determine if psychological and cognitive markers of resilience are bolstered via MT. Firefighters (n = 121) were assigned to an MT program (n = 42), an active-comparison relaxation training program (RT, n = 31), or served as no-training controls (NTC, n = 48). Both the MT and RT programs were contextualized for firefighters and consisted of 4, 2-h training sessions delivered over 4 weeks by the same expert trainer, as well as 10-15 min of daily out-of-class practice. Intent-to-treat analyses revealed a significantly greater increase in psychological resilience from baseline (T1) to post-training (T2) in firefighters who received MT vs. RT or no training. In addition, positive affect and objective attentional task performance demonstrated a greater increase over time (from T1 to T2) with more days per week of out-of-class practice for the MT group but not for the RT group. These results suggest that MT moreso than RT bolsters markers of resilience in firefighters.

15.
Phys Chem Chem Phys ; 21(29): 16154-16160, 2019 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-31294427

RESUMEN

The interaction between Pd and TiO2 for promoting photocatalytic activity was investigated by tailoring the size of Pd nanoparticles and monitoring the photocatalytic activity of methanol photo-reforming reaction for hydrogen gas production. We show that at 0.6 wt% Pd loading, the catalyst with highly dispersed nanoparticles obtained at 1 °C temperature exhibits superior photocatalytic activity for hydrogen gas production. At different weights of Pd loading, tailoring two sets of catalysts with different structural properties provides correlation between the changes in the Pd local structures and the rate of hydrogen production. The impact of controlling the structural properties of metal nanoparticles on influencing H2 production outweighs the effect of metal loading variation. The differences of Pd/TiO2 activity at the different metal loadings were correlated with the changes in the Pd local structure consequently affecting the electronic transfer and photocatalytic efficiency.

16.
Curr Opin Psychol ; 28: 273-278, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30999122

RESUMEN

There has been a proliferation of mindfulness training (MT) programs offered across a multitude of settings, including military, business, sports, education, and medicine. As such, ascertaining training effectiveness and determining best practices for program delivery are of the utmost importance. MT is often introduced to promote an array of desired effects from better mood, better leadership and management skills, to improved workplace or academic performance. Despite the diversity of factors motivating adoption of MTs, it can be argued from a cognitive training perspective that there should be uniformity in the core cognitive processes strengthened via repeated and systematic engagement in MT exercises. Herein, we explore the hypothesis that MT promotes salutary changes in the brain's working memory (WM) system. We review prior research and highlight aspects of MT programs that may be critical for achieving beneficial WM effects. Further, we suggest that given the centrality of WM in core processes such as emotion regulation, problem solving, and learning, MT programs capable of achieving WM benefits may be best positioned to promote other desired outcomes (e.g. reductions in negative mood). For these reasons, we recommend that more studies include WM metrics in their evaluation of MT programs.


Asunto(s)
Afecto , Memoria a Corto Plazo , Atención Plena , Práctica Psicológica , Humanos
17.
Prog Brain Res ; 244: 323-354, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30732844

RESUMEN

Cognitive ability is a key selection criterion for entry into many elite professions. Herein, we investigate whether mindfulness training (MT) can enhance cognitive performance in elite military forces. The cognitive effects of a short-form 8-h MT program contextualized for military cohorts, referred to as Mindfulness-Based Attention Training (MBAT), were assessed. Servicemembers received either a 2-week (n=40) or 4-week (n=36) version of MBAT or no training (NTC, n=44). Sustained attention and working memory task performance along with self-reported cognitive failures were assessed at study onset (T1) and 8-weeks later (T2). In contrast to both the NTC and 2-week MT groups, the 4-week MT group significantly improved over time on attention and working memory outcome measures. Among the 4-week more so than the 2-week MBAT participants, working memory performance improvements were correlated with their amount of out-of-class MT practice. In addition to these group-wise effects, all participants receiving MBAT decreased in their self-reported cognitive failures from T1 to T2. Importantly, none of these improvements were related to self-reported task motivation. Together, these results suggest that short-form MT, when delivered over a 4-week delivery schedule, may be an effective cognitive training tool in elite military cohorts.


Asunto(s)
Atención/fisiología , Cognición/fisiología , Memoria a Corto Plazo/fisiología , Personal Militar/psicología , Atención Plena/métodos , Adulto , Estudios de Cohortes , Femenino , Estado de Salud , Humanos , Masculino , Motivación , Escalas de Valoración Psiquiátrica , Reconocimiento en Psicología , Estrés Psicológico/fisiopatología , Estrés Psicológico/psicología , Encuestas y Cuestionarios , Factores de Tiempo , Estados Unidos
18.
J Theor Biol ; 466: 1-10, 2019 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-30658052

RESUMEN

The genetic code, as arranged in the standard tabular form, displays a non-random structure relating to the characteristics of the amino acids. An alternative arrangement can be made by organizing the code according to aminoacyl-tRNA synthetases (aaRSs), codons, and reverse complement codons, which illuminates a coevolutionary process that led to the contemporary genetic code. As amino acids were added to the genetic code, they were recognized by aaRSs that interact with stereochemically similar amino acids. Single nucleotide changes in the codons and anticodons were favored over more extensive changes, such that there was a logical stepwise progression in the evolution of the genetic code. The model presented traces the evolution of the genetic code accounting for these steps. Amino acid frequencies in ancient proteins and the preponderance of GNN codons in mRNAs for ancient proteins indicate that the genetic code began with alanine, aspartate, glutamate, glycine, and valine, with alanine being in the highest proportions. In addition to being consistent in terms of conservative changes in codon nucleotides, the model also is consistent with respect to aaRS classes, aaRS attachment to the tRNA, amino acid stereochemistry, and to a large extent with amino acid physicochemistry, and biochemical pathways.


Asunto(s)
Aminoácidos , Aminoacil-ARNt Sintetasas/genética , Anticodón , Codón , Evolución Molecular , Código Genético
19.
Genetica ; 147(2): 103-119, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30578455

RESUMEN

The initial components of ribosomes first appeared more than 3.8 billion years ago during a time when many types of RNAs were evolving. While modern ribosomes are complex molecular machines consisting of rRNAs and proteins, they were assembled during early evolution by the association and joining of small functional RNA units. Introns may have provided the means to ligate many of these pieces together. All four classes of introns (group I, group II, spliceosomal, and archaeal) are present in many rRNA gene loci over a broad phylogenetic range. A survey of rRNA intron sequences across the three major life domains suggests that some of the classes of introns may have diverged from one another within rRNA gene loci. Analyses of rRNA sequences revealed self-splicing group I and group II introns are present in ancestral regions of the SSU (small subunit) and LSU (large subunit), whereas spliceosomal and archaeal introns appeared in sections of the rRNA that evolved later. Most classes of introns increased in number for approximately 1 billion years. However, their frequencies are low in the most recently evolved regions added to the SSU and LSU rRNAs. Furthermore, many of the introns appear to have been in the same locations for billions of years, suggesting an ancient origin for these sequences. In this Perspectives paper, I reviewed and analyzed rRNA intron sequences, locations, structural characteristics, and splicing mechanisms; and suggest that rRNA gene loci may have served as evolutionary nurseries for intron formation and diversification.


Asunto(s)
Evolución Molecular , Intrones , ARN Ribosómico/genética , Animales , Humanos , ARN Ribosómico/química , ARN Ribosómico/metabolismo
20.
Nanoscale Adv ; 1(7): 2546-2552, 2019 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-36132726

RESUMEN

Sol-immobilization is increasingly used to achieve supported metal nanoparticles (NPs) with controllable size and shape; it affords a high degree of control of the metal particle size and yields a narrow particle size distribution. Using state-of-the-art beamlines, we demonstrate how X-ray absorption fine structure (XAFS) techniques are now able to provide accurate structural information on nano-sized colloidal Au solutions at µM concentrations. This study demonstrates: (i) the size of Au colloids can be accurately tuned by adjusting the temperature of reduction, (ii) Au concentration, from 50 µM to 1000 µM, has little influence on the average size of colloidal Au NPs in solution and (iii) the immobilization step is responsible for significant growth in Au particle size, which is further exacerbated at increased Au concentrations. The work presented demonstrates that an increased understanding of the primary steps in sol-immobilization allows improved optimization of materials for catalytic applications.

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